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== Da Costa’s Syndrome ==

'''Da Costa's Syndrome''' is a disorder of unknown origin<ref name="White">{{cite book | last = White | first = Paul Dudley | authorlink = | coauthors = | title = Heart Disease | publisher = MacMillan | date = 1951 | location = New York, New York | pages = 578-591 | url = | doi = | id = | isbn = }}</ref><ref name="pmid3314950">{{cite journal |author=Paul O |title=Da Costa's syndrome or neurocirculatory asthenia |journal=Br Heart J |volume=58 |issue=4 |pages=306–15 |year=1987 |pmid=3314950 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=3314950}}</ref><ref name="nature"> {{cite journal|title=The Nature of Chronic Fatigue Syndrome (CFS)|journal=J.A.M.A.|date=September 1996|first=David H.P.|last=Streeten|coauthors=|volume=280|issue=12|pages=Editorial|id= |url=http://www.mindfully.org/Health/Chronic-Fatigue-Syndrome-CFS.htm|format=|accessdate=2008-10-04 }}</ref> which involves a set of symptoms that include left-sided chest pains, palpitations, breathlessness, faintness, dizziness and fatigue occurring exclusively in response to physical exertion in some patients,<ref name="Lewis">Lewis T. (1919) The soldier’s heart and the effort syndrome, Paul B. Hoeber, New York.</ref> but in most cases the symptoms occur to a lesser degree at other times. The tendency to excessive tiredness during the day, and a reduced capacity for exertion<ref name="Baker">{{cite book | last = Baker | first = Doris M. | authorlink = | coauthors = | title = Cardiac Symptoms In The Neuroses | publisher = H.K.Lewis & Co.,Ltd. | date = 1955 | location = London | pages = 50 | url = http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=2500672&blobtype=pdf | doi = | id = | isbn = }}</ref><ref name="Wooley3"> {{cite journal|title=Early Hospitals Devoted to Heart Disease: Military Heart Hospital at Hampstead, England: World War 1|journal=American Heart Hospital Journal|date=2004|first=Charles F.|last=Wooley M.D.|coauthors=|volume=2|issue=|pages=175-177|id= |url=http://www3.interscience.wiley.com/journal/118818245/abstract?CRETRY=1&SRETRY=0|format=|accessdate=2008-11-08 }}</ref>, are the most prominent complaints.

The condition was first identified by J.M.DaCosta who observed it in soldiers during the [[American Civil War]] and later studied 300 patients to distinguish it from heart disease which has similar symptoms.<ref name="Irritable"> {{cite journal|title=On Irritable Heart|journal=The American Journal of the Medical Sciences|date=January 1871|first=Jacob Medes|last=Da Costa|coauthors=|volume=|issue=|pages=p.18-52|id= |url=|format=|accessdate=2008-02-13 }}</ref> Since then there have been many heated disputes and controversies<ref name="White">{{cite book | last = White | first = Paul Dudley | authorlink = | coauthors = | title = Heart Disease | publisher = MacMillan | date = 1951 | location = New York, New York | pages = 578-591 | url = | doi = | id = | isbn = }}</ref><ref name='White & Donovan'>{{cite book | last = White | first = Paul Dudley | authorlink = http://en.wikipedia.org/wiki/Paul_Dudley_White | coauthors = Helen Donovan | title = Hearts Their Long Follow-up | publisher = W.B.Saunders Company | date = 1967 | location = Philadelphia and London | pages = 300-308 | url = | doi = | id = | isbn = }}</ref><ref name="pmid3314950">{{cite journal |author=Paul O |title=Da Costa's syndrome or neurocirculatory asthenia |journal=Br Heart J |volume=58 |issue=4 |pages=306–15 |year=1987 |pmid=3314950 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=3314950}}</ref><ref name="Wooley2"> {{cite journal|title=Samuel A Levine's first world war encounters with Mackenzie and Lewis|journal=British Heart Journal|date=August 1990|first=Charles F.|last=Wooley|coauthors=J.M.Stang|volume=64|issue=2|pages=166-170|id=PMID PMC1024362 |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1024362|format=|accessdate=2008-11-08 }}</ref><ref name="Wooley4">{{cite book | last = Wooley | first = Charles F. | authorlink = | coauthors = | title = The Irritable Heart of Soldiers and the Origins of Anglo American Cardiology: the U.S. Civil War (1861) to World War 1 (1918) | publisher = Ashgate Publishing | date = 2002 | location = Aldershot U.K. | pages = 321 pp. | url = | doi = | id = | isbn = 0-7546-0595-7 (h/b) }}</ref> about it being heart disease or not<ref name="White">{{cite book | last = White | first = Paul Dudley | authorlink = | coauthors = | title = Heart Disease | publisher = MacMillan | date = 1951 | location = New York, New York | pages = 578-591 | url = | doi = | id = | isbn = }}</ref>, real or imaginary<ref name="White"/><ref name="Wood">{{cite journal|last=Wood|first=Paul|date=24 May 1941|title=Da Costa's Syndrome (or Effort Syndrome)|journal=British Medical Journal|volume=1(4194)|pages=767–772|url=http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=2161922&pageindex=1#page}}</ref>, genuine or malingering<ref name="Howell">{{cite journal|last = Howell|first = Joel|title="Soldier's heart": the redefinition of heart disease and speciality formation in early twentieth-century Great Britain. |journal = Medical History |pages=Supplement No. 5:34-52|date=1985|url=http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=2557403&blobtype=pdf}}</ref>, and physical or mental<ref name="Wheeler1950">Wheeler E.O. (1950), Neurocirculatory Asthenia et.al. - A Twenty Year Follow-Up Study of One Hundred and Seventy-Three Patients., [[Journal of the American Medical Association]], 25th March 1950, p.870-889 (Contributors to the study: Edwin O.Wheeler, M.D., [[Paul Dudley White]], M.D., Eleanor W.Reed, and Mandel E.Cohen, M.D.)</ref>, and more than 80 different theories and labels have been proposed and scientifically investigated<ref name="CohenLIfeSituations">{{cite journal
|author=Cohen ME, White PD |title=Life situations, emotions, and neurocirculatory asthenia (anxiety neurosis, neurasthenia, effort syndrome) |journal=Psychosom Med |volume=13 |issue=6 |pages=335–57 |year=1951 |pmid=14892184 |url=http://www.psychosomaticmedicine.org/cgi/pmidlookup?view=long&pmid=14892184 |accessdate=2008-05-28
}}</ref><ref name="thousand">{{cite web | lst = Kaplan | first = Melissa | title = The disease of a thousand names | url = http://www.anapsid.org/cnd/diagnosis/names.html|accessdate=2008-10-02}}</ref>.  Da Costa called it “irritable heart” but the most appropriate label according to Harvard professor [[Paul Dudley White]], who studied the subject for more than 50 years, was neurocirculatory asthenia.<ref name="White"/> Other authors have regarded Da Costa’s syndrome as the best name because it does not give any attribution to hypothesised cause and is therefore the most objective term.<ref name = "Wood"/>

The typical patient is a [[sedentary worker]] with a long, thin, flat, or narrow chest, and a stooped spine, as depicted in a life sized portrait which was previously displayed in the Museum of the Post-Graduate Medical School of London.<ref name="Wood2">{{cite book | last = Wood | first = Paul | authorlink = | coauthors = | title = Diseases of the Heart and Circulation 2nd. revised edition | publisher = Eyre & Spottiswoode | date = 1956 | location = London | pages = 937-947 | url = | doi = | id = | isbn = }}</ref> Notable medical authority Oglesby Paul summarised many of the Da Costa controversies in a 1987 edition of the [[British Heart Journal]]<ref name="pmid3314950">{{cite journal |author=Paul O |title=Da Costa's syndrome or neurocirculatory asthenia |journal=Br Heart J |volume=58 |issue=4 |pages=306–15 |year=1987 |pmid=3314950 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=3314950}}</ref> and since then the use of the term has become rare and, although the ailment is still a common and easily diagnosed problem, it has been absorbed into other modern categories of labelling.
The abnormal response to effort is consistent with the modern equivalent of [[effort intolerance]] which is a symptom of a type of [[postural orthostatic tachycardia syndrome]] which is a sub-type of the [[chronic fatigue syndrome]]<ref name="Harrisons">{{cite book | last = Fauci | first = Anthony S. | authorlink = | coauthors = et al. | title = Harrison's Principles of Internal Medicine 17th edition | publisher = McGraw-Hill Companies Inc. | date = February 2008 | location = New York U.S.A. | pages = 2703=2704 | url = | doi = | id = | isbn = }}</ref>
[http://www.cfids-cab.org/MESA/ccpc.html] <ref name="lu"> {{cite journal|title=Orthostatic Intolerance: Potential Pathophysiology and Therapy|journal=Chinese Journal of Physiology|date=2004|first=Chih-Cherng |last=Lu|coauthors=et.al|volume=47|issue=3|pages=102|id= |url=http://www.cps.org.tw/docs/47(3)%20101-109,%202004.pdf|format=|accessdate=2008-11-03 }}</ref>.
Other popularly used labels included soldier’s heart, effort syndrome, anxiety neurosis,<ref name="White"/><ref name="pmid3314950">{{cite journal |author=Paul O |title=Da Costa's syndrome or neurocirculatory asthenia |journal=Br Heart J |volume=58 |issue=4 |pages=306–15 |year=1987 |pmid=3314950 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=3314950}}</ref> and post-viral fatigue syndrome.<ref name="thousand"/> All modern ideas about cause and labelling have their strong adherents and opponents, however, none have yet been scientifically proven or universally accepted.

== History ==

===1864-1899===

Da Costa's syndrome is named after the surgeon Jacob Mendes Da Costa, who first observed it in soldiers during the [[American Civil War]]. The typical case was the civilian who enlisted in the army and was sent on long hours of marching, often up to twenty miles in one day, sometimes at double quick pace, with poor food and water, and in bad weather. They developed a viral infection and diarhoea and became exhausted and fell out of line and were hospitalised for treatment. After several months they recovered from the infection but when they returned to marching they were unable to keep up the pace as before and were again hospitalised, and although making a partial recovery they continued to suffer from abnormal palpitations, breathlessness and fatigue in response to mild exertion and were unfit for full military duty. Da Costa also noted that the pulse was always greatly and rapidly influenced by position, such as stooping or reclining.<ref name="Irritable"/>

Another physician, Earl de Grey, had previously presented four reports on British soldiers with these symptoms between '''1864''' and '''1868''', and attributed them to the heavy weight of military equipment being carried in knapsacks which were tightly strapped to the chest in a manner which constricted the action of the heart. Also in '''1864''', Henry Harthorme observed soldiers in the American Civil War who had similar symptoms which were attributed to “long-continued overexertion, with deficiency of rest and often nourishment”, and indefinite heart complaints were attributed to lack of sleep and bad food<ref name="Hartshorne">{{cite conference | first=Henry|last = Hartshorne|title=On heart disease in the army|date=3 June 1863|booktitle=College of Physicians, Philadelphia|url=http://www.civilwarsurgeons.org/articles/written_by_participants/heart_disease.pdf}}</ref>. In '''1870''' Arthur Bowen Myers of the Coldstream Guards also regarded the accoutrements as the cause of the trouble, which he called neurocirculatory asthenia and cardiovascular neurosis<ref name="Myers">{{cite book|last=Myers|first=Arthur|title=On the etiology and prevalence ofdiseases ofthe heart among soldiers, |publisher=Churchill| location=London|date=1870}}</ref><ref>{{cite book | last = Goetz | first = C.G. | authorlink = | coauthors = Turner C.M. and Aminoff M.J. editors | title = Handbook of Clinical Neurology | publisher = Elsevier Science Publishers | date = 1993 | location = B.V. | pages = 429-447 | url = | doi = | id = | isbn = }}</ref><ref>{{cite book | last = Goetz | first = C.G. | authorlink = | coauthors = Turner C.M. and Aminoff M.J. editors | title = Handbook of Clinical Neurology | publisher = Elsevier Science Publishers | date = 1993 | location = B.V. | pages = 429-447 | url = | doi = | id = | isbn = }}</ref><ref name="Mackenzie"> {{cite journal|title=Discussions On The Soldier's Heart|journal=Proceedings of the Royal Society of Medicine, Therapeutical and Pharmacological Section|date=1916-01-18|first=Sir James |last=Mackenzie|coauthors=R.M.Wilson, Philip Hamill, Alexander Morrison, O.Leyton, & Florence A.Stoney|volume=9|issue=|pages=27-60|id= |url=|format=|accessdate=2008-05-06 }}</ref>.

===1900-1919===

In '''1916''' Sir James MacKenzie chaired a major medical conference aimed at gaining a better understanding of the condition<ref name="Howell"/>. He attributed the fatigue to the abnormal pooling of blood in the abdominal and peripheral veins during exertion, which reduced blood flow to the brain. He also observed that the soldiers were fit and well at the start of the war, but after becoming severely exhausted by long marching or viral infections they recovered partially but with a reduced capacity for effort. They experienced abnormal palpitations and breathlessness which impaired their capacity to run fast, or to run up and down stairs, or to keep up with their comrades in marches as before.<ref name="Mackenzie"/>

Between '''1916''' and '''1919''' several synonyms were used to describe Da Costa's syndrome in World War 1, including soldier's heart and neurocirculatory asthenia. Sir Thomas Lewis gave it the title of the ''effort syndrome'' because he observed that in some cases the symptoms occurred exclusively in response to physical exertion.
Many of these patients had poor physiques with narrow or flat chests and a history of minor symptoms of the condition prior to enlisting in the army, and they often came from sedentary occupations which they chose because of difficulties in doing strenuous work. They had also avoided vigorous sports for similar reasons<ref name="Lewis"/>. Some of them enlisted several times and were repeatedly rejected but persisted until they were finally accepted, and then their symptoms were aggravated or caused by strenuous exertion at training camps, or while on long marches where they contracted viral infections, and after recovering from the fever they found that they could not sustain their former levels of activity. Graded exercise testing was used to gauge the severity of their condition, and both Lewis and Osler used it as a treatment<ref name="Lewis1918"> {{cite journal|title=Observations upon prognosis, with special reference to a condition described as the "irritable heart of soldiers"|journal=Lancet|date=1918|first=T.|last=Lewis|coauthors=|volume=i|issue=181-3|pages=|id= |url=|format=|accessdate=2008-10-22 }}</ref><ref name="Lewis"/><ref name="Osler"> {{cite journal|title=Graduated exercise in prognosis. Letter.|journal=Lancet|date=1918|first=Sir William|last=Osler|coauthors=|volume=|issue=1|pages=231|id= |url=|format=|accessdate=2008-10-25 }}</ref> which enabled some of the soldiers to return to full military duty, but others were put on light duties or discharged. After the war they generally changed to lighter occupations than they had before the war, and some were chronically incapacitated by their fatigue<ref name="Lewis"/>. 

===1920-1949===
In '''1939''' J.L. Caughey Jnr. reviewed the literature of internal medicine on the subject of cardiovascular neurosis which referred to cases that involved symptoms similar to those of heart disease occurring where there was no apparent disease of the heart or blood vessels. The typical patient had his tonsils and appendix removed as a child, as well as many infectious illnesses and colds. He had a thin physique, and a weak stomach, and his kidneys had been damaged by [[Scarlet fever]], and there were frequent fluctuations in the color and volume of his urine. His blood pressure was unstable, and his peripheral circulation was poor, with pale fingers and toes in cold weather. He had difficulty with concentrating and thinking clearly and had a poor memory. They had a respiratory infection three years prior to suffering from pain in his heart, shortness of breath, dizziness, faintness and weakness. All of his symptoms were “made worse by exertion or nervous strain”. They often felt breathless and would complain of not being able to expand their chest far enough to get a full breath. Caughey also noted previous exercise tests which indicated "a physiological abnormality in the patient as compared to the normal person”, but he believed that it was due to their fear that exercise would cause a heart attack. In describing the lack of stamina he suggested that there were two groups of patients, the first who never developed the ability to persevere against the challenges and adversities of life, and those who tried but gave up.<ref name="Caughey"> {{cite journal|title=Cardiovascular Neurosis; A Review|journal=Psychosomatic Medicine|date=April 1939|first=J.L. Jnr.|last=Caughey|coauthors=|volume=1|issue=3|pages=311-324|id= |url=|format=|accessdate=2008-04-26 }}</ref>

In the '''1940’s''' there were several studies aimed at determining the physical basis of these conditions<ref name = "Wood"/><ref name="CohenLowO2"> {{cite journal|title=Low oxygen consumption and low ventilatory efficiency during exhausting work in patients with neurocirculatory asthenia, effort syndrome, anxiety neurosis|journal=Journal of Clinical Investigation|date=1946 Nov.|first=Mandel E.|last=Cohen|coauthors=R.E. Johnson, F.C. Consolazio, P.D. White|volume=25|issue=6|pages=920|id= |url=|format=|accessdate=2008-01-20 }}</ref> and in '''1947''' S.Wolf studied the "respiratory distress characterized by inability to get a full breath” and found that the thoracic diaphragm function was abnormal, and when the diaphragms contractile state during inspiration was such that adequate inspiration was no longer possible, breathlessness occurred with a feeling of inability to take a full breath. The spasm of the diaphragm was often accompanied by pains in the chest and shoulder, occlusion of the lower end of the esophagus, and difficulty swallowing.<ref name="Wolf"> {{cite journal|title=Sustained Contraction of the Diaphragm, the Mechanism or a Common Type of Dyspnoea and Precordial Pain|journal=Journal of Clinical Investigation|date=1947 November|first=S.|last=Wolf|coauthors=|volume=26|issue=|pages=1201|id= |url=http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=439463&pageindex=29|format=|accessdate=2008-03-23 }}</ref> Also in '''1947''' a report by Cohen and White noted that the complete mechanism of Da Costa syndrome symptoms was unknown but when respiration was investigated objective abnormalities were found, "just as when other symptoms of N.C.A. are investigated with objective methods, which demonstrates that the abnormalities are not all in the subjective sphere". The respiratory abnormalities at rest were few but during exercise the abnormalities became more pronounced and the deviations from the normal became greater as the rate and amount of exercise increased.<ref name="Cohen">{{cite journal|title=Studies of Breathing, Pulmonary Ventilation and Subjective Awareness of Shortness of Breath (Dyspnea) in Neurocirculatory Asthenia, Effort Syndrome, Anxiety Neurosis|journal=The Journal of Clinical Investigation|date=May 1947|first=Mandel |last=Cohen|coauthors=Paul D. White|volume=26|issue=3|pages=520-529|id= |url=http://www.pubmedcentral.nih.gov/pagerender.fcgi?tool=pmcentrez&artid=439184&blogtype=pdf|format=|accessdate=2008-02-04 }}</ref>

===1950-1979===

In '''1950''' Edmund Wheeler presented the results of a 20-year longitudinal study of 173 patients with "effort syndrome" and found that the condition involved varying degrees of disability but all patients tended to improve with a low-stress lifestyle. He concluded that, although they all had what was called ‘anxiety’, they did not develop a higher frequency of illnesses  such as peptic ulcers, diabetes, or asthma etc, “which have recently been said to be caused by anxiety” and that “there is no evidence that anxiety causes these diseases”.<ref name="Wheeler1950"/>
 

In '''1951''' the fourth edition of [[Paul Dudley White]]’s book “Heart Disease” contained a chapter on “Neurocirculatory Asthenia”, because, as he explains, the symptoms are similar to heart disease, but are not the same, and he adds, that they are also similar to, but can occur in the absence of anxiety, and are not exactly like those produced by effort in a normal healthy person, and therefore need to be discussed separately.

He describes the typical group of symptoms which are precipitated by excitement or effort, and stated that “it constitutes a kind of fatigue syndrome” and in some cases “it is more or less a chronic condition,” and that regardless of it’s pathogenesis it was a real illness. In some patients the neurocirculatory symptoms were most prominent, but for some unknown reason there were other cases where the main symptoms were gastrointestinal or cerebral. The general causes of the condition appear to include such strains as worry over business, social, or family matters, emotional conflicts, physical or nervous fatigue, and exhaustion from acute infections or illnesses. The organic basis was not known although the possibilities which had been considered in the previous 25 years, included thyrotoxicosis, low-grade infection, adrenal hyperactivity, [[hyperventilation]] resulting in alkalosis, and lack of salt, but none have been confirmed. Many of the patients had thin physiques with an “unusually vertical position of the heart”, and “abnormality of shape of the capillary loops at the base of the nail”...“It is common to find that close relatives have had similar problems, and recent studies indicated that it was one of the Mendelian dominant group of inherited disorders.” It was common in World War 1, occurred in civilians as well as soldiers, and it is generally seen in young adults, but can occur at any age, and is more common in women than men. 
The frequent sighing distinguishes the condition from heart disease, and the fatigue sometimes produces more incapacity, and even complete disability. It is a real and not an imaginary incapacity, even though at first glance it may have appeared imaginary in World War 1 (1914-1918) when it was sometimes labelled "malingering", and even though in civilian practice it has frequently been diagnosed as "mere nervousness". It is milder in civilian life than in war and it is so commonly associated with psycho-neurosis of the anxiety type “that the two conditions have sometimes been confused one for the other or considered to be synonymous, the term [[anxiety neurosis]] having come to mean for many the same collection of symptoms which identify neurocirculatory asthenia.”

Treatment involves rest for days or months or as long as required, and elaborate psychotherapy is generally not needed.  "The condition must be discussed seriously, not lightly as if it was of no importance”, and it is equally wrong to dismiss it as negligible or imaginary, as it is to to regard it as dangerous or serious and a threat to life which demands bed rest. Management of the symptoms involves normal but quiet work and play and the avoidance of long working hours or burdensome tasks. Like most people these patients usually try to keep up with their friends in strenuous living in the business, professional, or social world but with clear medical advice they soon learn the benefits limiting their activities and gradually adjust them to suit their symptoms, and are surprised at recapturing a feeling of well being."<ref name="White"/>

In '''1956''' Paul Wood’s 2nd edition of Diseases of the Heart and Circulation included a chapter on the effort syndrome. He described how it “is characterised by a group of symptoms which unduly limit the subject's capacity for effort" and recorded that "The cardinal symptoms" of irritable heart, soldier’s heart, disordered action of the heart (D.A.H.), etc. are "breathlessness (93%), palpitations (89%), fatigue (88%), left inframammary pain (78%), and dizziness (78%), or syncope (fainting) (35%)". He also suggested a variety of methods for diagnosing the difference between the symptoms and those of heart disease. For example the chest pain usually involved a sharp stabbing sensation in the lower ribs caused by prolonged poor posture. He noted that the location of the pain was so near the heart that “it seems to convince the patient that his heart is diseased”, especailly because of the palpitations that occur at other times. It was natural to draw that conclusion but some patients developed a morbid fear of heart disease and death, however, although the exact mechanism was not known, it could be “immediately abolished by the intramuscular injection of 2 ml. of novocaine at the site of maximum intensity and tenderness”, indicating that it was in the muscle between the ribs and was related to fibrositis.
The breathlessness involved frequent deep sighs brought on by exercise, but were also common at other times, and the patients will say they are not able to obtain a full and satisfying breath. This can also occur at night when it "may be confused with asthma. "A simple test" for the symptom involves forced hyperventilation where "The patient is asked to breath deeply and rapidly for one minute." When a healthy person is asked to stop he feels breathless for about 20 seconds, but a patient with Da Costa's syndrome "continues forced breathing, explaining later that he felt breathless." i.e. there is an abnormal breathing pattern - "[[Dyspnoea]]" instead of insufficient breathing - "[[apnoea]]". Also "Normal subjects have no difficulty holding the breath for at least 30 seconds, but patients with Da Costa's syndrome usually give up very quickly. With regard to the fatigue the patients often do not feel refreshed when they wake up in the morning, and they may "feel tired and listless during the day. The other type of fatigue which is related to effort involves a delay in the return of pulse rate after exertion.<ref name="Wood2"/>. In considering the influence of psychological factors he noted that the similarity of the symptoms to heart disorders may be the cause of a fear of heart disease (cardiophobia), which contributes to the reluctance to exercise (i.e. resulting in exercise phobia), and that all of the symptoms may have originated from a general [[anxiety neurosis]] resulting from genetic or familial factors, or poor health during childhood, and the consequent lack of exercise and the avoidance of sport during childhood.

In '''1976''' Charles Wooley presented an article about the history of Da Costa’s syndrome in the journal called ‘Circulation’.  He reported that Da Costa originally called it ‘irritable heart’ when he noticed the condition amongst soldiers during the American Civil War. However he added that a later study by Thomas Lewis revealed that most of the soldiers who had the problem came from sedentary occupations and “a large percentage” were “affected by the condition in civil life many years before joining the Army” and that it was not particularly a soldiers malady, and that it also affected some athletes. A further study in 1941 by Paul Wood reported that it was commoner in women<ref name = "Wood"/>.

The author also noted that possibly several distinct, but similar conditions were causing confusion in diagnosis, and concluded that many of Da Costa’s original patients had been described as having occasional cardiac sounds and murmurs that could now be included in the newly evolving category of [[mitral valve prolapse syndrome]]. He then recommended deferred judgement about the nature of the other cases, where advances in technology were likely to provide a more precise understanding of the relationship between the various causes <ref name="yesteryear"> {{cite journal|title=Where are the Diseases of Yesteryear?|journal=Circulation (the official journal of the American Heart Association|date=May 1976|first=Charles F.|last=Wooley M.D.|coauthors=|volume=53|issue=No. 5|pages=749-751|id= |url=http://www.circ.ahajournals.org/cgi/reprint/53/5/749|format=|accessdate=2008-09-24 }}</ref>.

===1980-1999===

In '''1980''' Soviet researcher V.S.Volkov studied the physical fitness levels of patients with angina heart disease, and compared them to those with neurocirculatory dystony (Da Costa’s syndrome). He divided heart disease patients into three groups with heart pain at rest, heart pain every day, and heart pain occasionally. He also divided NCD patients into three stages of mild, moderate, and severe. 80% of Da Costa’s syndrome patients were fitter than heart disease patients, but 20% were not, and had to stop the exercise because of changes in their heart rate, or overwhelming and radiating chest pain, general fatigue, and fear for their hearts.<ref name="Volkov"> {{cite journal|title=Psychosomatic Interrelations and their importance in patients with cardiac type type NCD|journal=Soviet Medicine|date=1980|first=V.S.|last=Volkov|coauthors=|volume=|issue=11|pages=9-15|id= |url=|format=English abstract|accessdate=2008-09-24 }}</ref>

In '''1987''' prominent Harvard researcher Oglesby Paul presented a ten page history of Da Costa’s syndrome in the [[British Heart Journal]], in which he outlined all of the controversies of the previous hundred years. He reported that many theories and labels had been proposed, but for each one which had supporting evidence, there were other studies which contradicted the findings. For example, if one study presents anxiety as a cause, another study will find patients who are not anxious, another study will report hyperventilation as a cause, yet there will also be studies which show patients who don’t hyperventilate, and for each study that shows a relationship to mitral valve prolapse syndrome there will be others that show no evidence of MVP. He concluded that the condition still existed, and was easy to diagnose, effecting 4% of the population, but that there were newer more popular labels, such as ‘anxiety state’, where he added that such labels would do no harm as long as the important history of the subject was not forgotten.<ref name="pmid3314950"/>

In '''1998''' David Streeten presented an article in JAMA<ref name="nature"> {{cite journal|title=The Nature of Chronic Fatigue Syndrome (CFS)|journal=J.A.M.A.|date=September 1996|first=David H.P.|last=Streeten|coauthors=|volume=280|issue=12|pages=Editorial|id= |url=http://www.mindfully.org/Health/Chronic-Fatigue-Syndrome-CFS.htm|format=|accessdate=2008-10-04 }}</ref>, explaining that the fatigue reported by Da Costa and Lewis were early descriptions of a “newly recognised” delayed form of orthostatic hypotension which is a feature of some types of Chronic Fatigue Syndrome. He stated that “as a working hypothesis”, the fatigue was due to abnormal pooling of blood in the lower limbs which delayed and reduced the flow of blood and oxygen supply to the brain. That effect was compounded by a reduced circulating red blood cell mass. He then emphasised that it is essential to identify these physical abnormalities by repeatedly measuring the patients blood pressure in recumbency and after standing for ten minutes or [[tilt test]]ing, and that “it is inappropriate to consider that CFS is a manifestation of mental disorder” unless those physical causes are excluded. He added that the expense of these tests was not unreasonable considering that almost every type of work or lifestyle required a person to stand for six hours per day without experiencing the symptoms associated with reduced blood pressure. He then concluded that the instigating cause remains unknown, and that effective and safe treatments for the debilitating symptoms are still not available and that further research is required.<ref name="nature"/>

===The relevance to modern labelling terminology between 2000-2008===

The use of the term [[Da Costa's syndrome]] has fallen out of fashion and is rarely used nowadays,<ref name="pmid3314950"/>  however to put it into context with modern labels there are some relevant descriptions from the history of research. In that regard, in '''1916''' Thomas Lewis noted that in some cases the condition was exclusively related to exertion,<ref name="Baker"/><ref name="Lewis"/> and in '''1956''' Paul Wood O.B.E. described it as a syndrome of six clearly identifiable symptoms (which had previously been called "primary"<ref name="Howell"/> "typical" <ref name="Hurst">{{cite book | last = Hurst | first = J.W. | authorlink = | coauthors = R.B.Logue, R.C.Schlant, N.K.Wenber | title = The Heart 3rd. edition | publisher = McGraw Hill Book Co., | date = 1974 | location = New York | pages = 1552-1555 | url = | doi = | id = | isbn = }}</ref> “characteristic”<ref name='Cohen Familial'/> or "classic"<ref name="White"/> and which he called "cardinal" symptoms<ref name="Wood2"/>, and Harvard professor [[Paul Dudley White]] described it as a definite malady which was a type of fatigue syndrome that is more or less chronic.<ref name="White"/>
Nowadays those typical, distinct, or characteristic features can be seen in conditions which include the symptom with the misnomer of [[effort intolerance]] (which should be effort limitations) due to exercise induced [[postural hypotension]].<ref name="Mackenzie"/><ref name="Wood2"/><ref name="Raj"> {{cite journal|title=The Postural Tachycardia Syndrome (POTS): Pathophysiology, Diagnosis & Management|journal=Indian Pacing Electrophysiology. Journal|date=2006|first=Satish R.|last=Raj|coauthors=|volume=6|issue=2|pages=84-99|id= |url=http://www.ipej.org/0602/raj.htm|format=|accessdate=2008-10-28 }}</ref> For example, it is seen in one type of the [[Postural Orthostatic Tachycardia Syndrome]], which is in turn one of the many types of [[chronic fatigue syndrome]]<ref name="Harrisons"/>
<ref name="nature"/><ref name="Raj"/><ref name="Rowe">{{cite journal|title=Editorial: Orthostatic Intolerance and Chronic Fatigue Syndrome: New Light On An Old Problem|journal=Journal of Pediatrics|date=April 2002|first=P.C.|last=Rowe|coauthors=|volume=140|issue=4|pages=387-389|id=PMID 12006948 |url=http://www.prohealth.com/me-cfs/library/showarticle.cfm?id=3586&t=CFIDS_FM|format=|accessdate=2008-10-31 }}</ref><ref name="Wooley4"/> <ref name="Stewart"> {{cite journal|title=Vascular perturbations in the chronic orthostatic intolerance of the postural orthostatic tachycardia syndrome.|journal=Journal of Applied Physiology|date=May 24th 2000|first=Julian M.|last=Stewart|coauthors=Amy Weldon|volume=89|issue=|pages=1505-1512|id= |url=http://www.ncbi.nlm.nih.gov/pubmed/11007589|format=|accessdate=2008-11-08 }}</ref><ref name="lu"/>.
However, there are still many different ideas about cause, and the condition has been virtually lost in a sea of other labels<ref name="Baker"/><ref name="pmid3314950"/><ref name=”Nixon2”> {{cite journal|title=Effort syndrome: Hyperventilation and reduction of anaerobic threshold|journal=Journal of Applied Psychophysiology and Biofeedback|date=June 1994|first=G.F.|last=Nixon|coauthors=|volume=19|issue=2|pages=155-169|id= {{doi|10.1007/BF01776488}}|url=http://www.springerlink.com/content/k344t32866634227/|format=|accessdate= }}</ref> and although there is a vast amount of direct and indirect research evidence for physical cause<ref name="Wolf"/><ref name="Cohen"/><ref name="Hurst"/>, none have been universally accepted<ref name="CohenLIfeSituations"/>. The topic remains the subject of ongoing controversy amongst imprecisely defined [[anxiety disorder]]s, poorly characterised [[post-war syndrome]]s<ref name='Hyams'> {{cite journal|title=War Syndromes and Their Evaluation: From the U.S. Civil War to the Persian Gulf War|journal=Annals of Internal Medicine|date=September 1996|first=Kenneth|last=C.Hyams, M.D.|coauthors=et.al|volume=125|issue=5|pages=398-405|id= |url=http://www.annals.org/cgi/content/full/125/5/398|format=|accessdate=2008-12-02 }}</ref><ref name="pmid15274499">{{cite journal |author=Engel CC |title=Post-war syndromes: illustrating the impact of the social psyche on notions of risk, responsibility, reason, and remedy |journal=J Am Acad Psychoanal Dyn Psychiatry |volume=32 |issue=2 |pages=321–34; discussion 335–43 |year=2004 |pmid=15274499 |doi=}}</ref><ref name="isbn3-8055-8184-X">{{cite book |author=Clark MR, Treisman GL (eds.) |title=Pain And Depression: An Interdisciplinary Patient-centered Approach (Series: Advances in Psychosomatic Medicine, vol. 25) |publisher=Karger |location=Basel |year=2004 |pages=176 |isbn=3-8055-7742-7 |oclc= |doi=}}</ref>, and the complex [[Chronic fatigue syndrome|CFS]] group of ailments<ref name='Hyams'/><ref name="Ware"> {{cite journal|title=Sociomatics and Illness Course in Chronic Fatigue Syndrome|journal=Psychosomatic Medicine|date=1998|first=Norma C.|last=Ware|coauthors=|volume=60|issue=|pages=394-401|id= |url=http://www.psychosomaticmedicine.org/cgi/reprint/60/4/394.pdf|format=|accessdate=2008-11-28 }}</ref><ref name="titleOMIM - ORTHOSTATIC INTOLERANCE">{{OMIM|604715|Orthostatic Intolerance}}</ref><ref name="Scondorf"> {{cite journal|title=The importance of orthostatic intolerance in the chronic fatigue syndrome|journal=Am.J.Med.Sci.|date=1999|first=R.|last=Schondorf|coauthors=R.Freeman|volume=317|issue=|pages=117-123|id=PMID 10037115 |url=|format=|accessdate=2008-10-19 }}</ref><ref name="Rowe"/><ref name="Raj"> {{cite journal|title=The Postural Tachycardia Syndrome (POTS): Pathophysiology, Diagnosis & Management|journal=Indian Pacing Electrophysiology. Journal|date=2006|first=Satish R.|last=Raj|coauthors=|volume=6|issue=2|pages=84-99|id= |url=http://www.ipej.org/0602/raj.htm|format=|accessdate=2008-10-28 }}</ref>, Opinions differ from one medical specialist to another<ref name="Harrisons"/><ref name="Wooley4"/><ref name="lu"/>, from one medical authority to another, and from one medical consumer group to another, and change regularly<ref name="Ware"/><ref name="thousand"/><ref name="lu"/>. Dictionary definitions and label priorities also alter with the changes in opinion, however the Merriam Webster online Medical Dictionary [http://www.mcgraw-hill.co.uk/tpr/bookshops/customer_kits/ck_med_mar08.pdf] includes a definition of [[neurocirculatory asthenia]], with the typical symptoms occurring in relation to exertion and in the absence of heart disease, and provides the synonyms of "cardiac neurosis, effort syndrome, irritable heart, and soldier's heart" <ref>{{cite web | title = 
Merriam-Webster Medical Dictionary | url = http://www.intelihealth.com/cgi-bin/dictionary.cgi?adv=0&book=Medical&t=9276&p=~br,RNM%7c~st,331%7c~r,WSRNM000%7c~b,*%7c&WEB_HOME=/IH/&WEB_HOST=http://www.intelihealth.com&MIVAL=ihtIH&va=neurocirculatory+asthenia | accessdate=2008-06-10}}</ref>, which were the most frequently used synonyms for Da Costa’s syndrome.<ref name="White"/><ref name="pmid3314950"/> Indeed [[Dorland's medical reference works|Dorland's medical dictionary]] lists Da Costa's syndrome and neurocirculatory asthenia as direct synonyms<ref name="Dorland's">{{cite web |url=http://www.mercksource.com/pp/us/cns/cns_hl_dorlands_split.jsp?pg=/ppdocs/us/common/dorlands/dorland/two/000027276.htm |title=Dorlands Medical Dictionary:Da Costa syndrome |format= |work= |accessdate=2008-10-06}}</ref> and the current 2008 edtion of Harrison’s Principles of Internal Medicine describes the symptoms of the modern term [[chronic fatigue syndrome]] as being “not new” with the comment that in the past it may have been diagnosed as the “effort syndrome”<ref name="Harrisons"/> defined in 1919 by Lewis<ref name="Lewis1918"/><ref name="Lewis">Lewis T. (1919) The soldier’s heart and the effort syndrome, Paul B. Hoeber, New York.</ref>. 

== Symptoms ==
The typical symptoms of Da Costa’s syndrome are palpitations, breathlessness, chest pains, and or fatigue<ref name="Wood2"/><ref name="Hurst"/><ref name="Fleming">{{cite book | last = Fleming | first = P.R. | authorlink = | coauthors = | title = A Short History of Cardiology | publisher = Clio Medica, Wellcome Institute | date = 1997 | location = Amsterdam and Atlanta | pages = 159 | url = http://books.google.com.au/books?id=DA4I7yfAEOoC&pg=PA159&lpg=PA159&dq=graded+exercise+soldier's+heart&source=web&ots=00Srm3vARC&sig=Y_OXyxhUegh08pvrQQw5AWyT3mE&hl=en&sa=X&oi=book_result&resnum=7&ct=result | doi = | id = | isbn = }}</ref><ref name='Howell'/> occurring exclusively in response to physical exertion in some cases<ref name="Lewis"/><ref name="Wood2"/><ref name="Wooley3"/>, and occasionally to changes in posture<ref name='Whishaw'/><ref name='Howell'/>, but in many patients they are also associated with some viral infections or nervous strains.<ref name="White"/><ref name="Caughey"/>
*The palpitations occur as a more forceful and rapid beating of the heart than usual and are generally associated with stress or exertion.<ref name="White"/>
*The breathlessness is related to spasm and inefficient function of the thoracic diaphragm<ref name="Wolf"/><ref name = "Wood"/><ref name="CohenLowO2"/><ref name="Cohen">{{cite journal|title=Studies of Breathing, Pulmonary Ventilation and Subjective Awareness of Shortness of Breath (Dyspnea) in Neurocirculatory Asthenia, Effort Syndrome, Anxiety Neurosis|journal=The Journal of Clinical Investigation|date=May 1947|first=Mandel |last=Cohen|coauthors=Paul D. White|volume=26|issue=3|pages=520-529|id= |url=http://www.pubmedcentral.nih.gov/pagerender.fcgi?tool=pmcentrez&artid=439184&blogtype=pdf|format=|accessdate=2008-02-04 }}</ref> which is the primary breathing muscle, and it features occasional slow, forced, deep breaths - abnormal sighs or yawns<ref name="Caughey"/><ref name='Whishaw'> {{cite journal|title=A Review of the Physical Condition of Returned Soldiers Suffering from the Effort Syndrome|journal=The Medical Journal of Australia|date=December 16th 1939|first= R.|last=Whishaw|coauthors=|volume=|issue=|pages=891-893|id= |url=|format=|accessdate=2008-12-05 }}</ref><ref name="CohenLIfeSituations"/><ref name="Cohen"/><ref name="White"/><ref name="Baker"/><ref name = "Wood"/><ref name="Hurst"/>.The person often feels as if they cannot get a full breath, and they tend to avoid crowded buses, trains and  theatres, and they prefer to sit near open windows to get fresh air, or in aisle seats so that they can leave the room quickly if necessary, and in some cases they avoid open spaces where there are crowds. This was due to an abnormal build up of CO2 exhaled by the crowd in a confined space, which tended to increase the frequency of sighs and ultimately cause all of the physical symptoms of the condition, and sometimes a sense of suffocation and a sense of fear that resembled anxiety attacks<ref name="CohenLIfeSituations"/>.
*The most common chest pain is a dull ache or tenderness in the lower left side of the chest with occasional brief, sharp and stabbing sensations in that area<ref name="Lewis"/><ref name="White"/><ref name="Baker"/><ref name="CohenLIfeSituations"/><ref name = "Wood"/><ref name="Wood2"/><ref name="pmid3314950"/><ref name="Hurst"/>, and there may sometimes be cramping paiins in the muscles on the far left or right side of the chest brought on by muscualr efforts <ref name = "Wood"/><ref name="Wood2"/><ref name="White"/>such as the strain of  “lifting a heavy weight”, especially at awkward angles - “in such actions as cranking an engine” <ref name = "Wood"/><ref name="Wood2"/>.
*The fatigue involves an abnormal pattern of tiredness during the day<ref name='Cohen Familial'> {{cite journal|title=The high familial prevalence of neurocirculatory asthenia, anxiety neurosis, effort syndrome|journal=American Journal of Human Genetics|date=June 1951|first=Mandel E.|last=Cohen|coauthors=Daniel W.Badal, Alice Kilpatrick, W.Reed, and Paul D.White|volume=3|issue=2|pages=126-158|id=PMID PMCID: PMC1716324 |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1716324|format=|accessdate=2008-12-02 }}</ref> and an excessive response to physical exertion, and is unlike normal fatigue insofar as it tends to persist despite rest<ref name = "Baker"/>. It is related to abnormal pooling of blood in the abdominal and peripheral veins which reduces blood flow to the heart and brain<ref name="Lewis"/><ref name="Rowe"/> , especially during exertion, which explains why faintness and dizziness are often additional features, and why most patients have a reduced capacity for exertion.<ref name="Mackenzie"/><ref name="Wood2"/><ref name="nature"/><ref name="Harrisons"/>

== Predisposing factors ==
The condition may be genetic or familial<ref name = "Wood"/><ref name='Cohen Familial'/><ref name="Cohen"/><ref name="Wood2"/><ref name="Wheeler1950"/><ref name="Caughey"/><ref name="Hurst"/><ref name="pmid3314950"/> and is more likely to affect individuals who had multiple infectious illnesses and surgical procedures during childhood<ref name="Lewis"/><ref name="Caughey"/>, and who had thin<ref name="Mackenzie"/><ref name='Jones'> {{cite journal|title=The effect of Exercise on Soldiers with Neuro-circulatory asthenia|journal=Psychosomatic Medicine|date=1946|first=Maxwell|last=Jones|coauthors=R.Scarisbrick|volume=|issue=8|pages=188-192|id= |url=http://www.psychosomaticmedicine.org/cgi/reprint/8/3/188.pdf|format=|accessdate=2008-12-02 }}</ref><ref name="White"/><ref name="Linford Rees"> {{cite journal|title=Physique and Effort Syndrome|journal=Journal of Mental Science|date=1945|first=W.|last=Linford Rees|coauthors=|volume=91|issue=|pages=89-92|id= {{doi|10.1192/bjp.91.382.89}}|url=http://bjp.rcpsych.org/cgi/content/abstract/91/382/89|format=|accessdate=2008-11-14 }}</ref> and stooped physiques<ref name="Lewis 3">{{cite book | last = Lewis | first = Sir Thomas | authorlink = | coauthors = | title = The soldier's heart and the effort syndrome 2nd. edition | publisher = Shaw | date = 1940 | location = London | pages = | url = | doi = | id = | isbn = }}</ref><ref name = "Wood"/> <ref name="yesteryear"/><ref name="White"/><ref name="Hurst"/>, and sedentary workers<ref name="Lewis"/> who avoided or never played sport<ref name="Lewis"/><ref name="Caughey"/><ref name="White"/><ref name="Wood2"/><ref name="yesteryear"/>, and it is more common in women<ref name="CohenLIfeSituations"/><ref name="Wheeler1950"/><ref name = "Wood"/><ref name="White"/><ref name="Hurst"/><ref name="pmid3314950"/><ref name="Stewart"/><ref name="lu"/>, and often occurs or starts during a pregnancy<ref name="Wheeler1950"/><ref name="CohenLIfeSituations"/><ref> {{cite journal|title=Evaluation of present day trends in obstetrics|journal=J.A.M.A.|date=1950|first=D.E.|last=Reid|coauthors=M.E.Cohen|volume=142|issue=|pages=615|id= |url=|format=|accessdate=2008-10-18 }}</ref>. Most soldiers who developed the condition were former sedentary workers who had minor indications of the typical symptoms prior to the war.<ref name="Irritable"/><ref name="Lewis"/><ref name="CohenLIfeSituations"/><ref name="yesteryear"/>

== Onset of symptoms ==
In some cases the condition appears to have been present since birth, or ever since the patient can remember<ref name="Caughey"/><ref name='Jones'/> {{cite journal|title=The effect of Exercise on Soldiers with Neuro-circulatory asthenia|journal=Psychosomatic Medicine|date=1946|first=Maxwell|last=Jones|coauthors=R.Scarisbrick|volume=|issue=8|pages=188-192|id= |url=http://www.psychosomaticmedicine.org/cgi/reprint/8/3/188.pdf|format=|accessdate=2008-12-02 }}</ref><ref name="Cohen"/><ref name="Wheeler1950"/><ref name='Cohen Familial'/>, but it is often gradual in onset without the patient noticing it or being able to identify an obvious cause<ref name="CohenLIfeSituations"/>, or it may start and recur or persist after a viral infection<ref name="Irritable"/><ref name="Mackenzie"/><ref name="Lewis"/><ref name="CohenLIfeSituations"/><ref name="Wood2"/><ref name="pmid3314950"/>, or after an excessive or prolonged period of physical<ref name="Irritable"/><ref name="Lewis"/><ref name="CohenLIfeSituations"/><ref name='Hyams'/> or emotional stress<ref name="Hartshorne"/><ref name="Wheeler1950"/><ref name="White"/>. The average age of onset is 25 years<ref name='Cohen Familial'/><ref name="CohenLIfeSituations"/><ref name="Hurst"/>.

== Causes ==
According to J.M.Da Costa in his original paper of 1871 the causes were "Fevers" 17%, "Diarrhoea" 30.5%, "Hard field service, particularly excessive marching" 34.5%, and finally, "Wounds, injuries, rheumatism, scurvy, ordinary duties of soldier life, and doubtful causes" 18%.<ref name="Irritable"/><ref name='Howell'/>

Since Da Costa’s initial report several authors have proposed that anxiety<ref name="White"/><ref name="pmid3314950"/><ref name="Dorland's">{{cite web |url=http://www.mercksource.com/pp/us/cns/cns_hl_dorlands_split.jsp?pg=/ppdocs/us/common/dorlands/dorland/two/000027276.htm |title=Dorlands Medical Dictionary:Da Costa syndrome |format= |work= |accessdate=2008-10-06}}</ref> related to personal or business stress<ref name="Wheeler1950"/><ref name="Wood2"/><ref name="White"/>, pregnancy<ref name="Wheeler1950"/><ref name="CohenLIfeSituations"/> and malnutrition<ref name="Hartshorne"/><ref name="White"/><ref name="CohenLIfeSituations"/><ref name='Hyams'/>  can be added to the list of causes. 

== General Physical Characteristics==
Da Costa’s syndrome can affect individuals of any type of physique, but they are generally thin<ref name="Mackenzie"/><ref name='Cohen Familial'/><ref name='Jones'/><ref name="White"/><ref name="Linford Rees"/>, with various chest wall deformities and stooped or scoliotic spines<ref name="Lewis"/><ref name="yesteryear"/><ref name = "Wood"/><ref name="Wood2"/><ref name="Hurst"/>. They are generally, but have not always been poor athletes and swimmers<ref name="Cohen"/><ref name="CohenLIfeSituations"/>, and have an abnormally functioning thoracic diaphragm which results in inefficient breathing and the tendency to sigh more often than usual.  They also have a reduced capacity to hold their breath<ref name="Lewis"/>, and an intolerance to carbon dioxide which brings on their symptoms<ref name="CohenLIfeSituations"/><ref name="pmid3314950"/>, as does wearing a gas mask<ref name="yesteryear"/><ref name = "Wood"/><ref name="Cohen"/> and the infusion of sodium lactate<ref name="Hurst"/>. Other common distinguishing features are abnormalities in the shape of their fingernail capillaries,<ref name="White"/><ref name = "Wood"/><ref name="Hurst"/> and dermatographia where running a finger nail lightly down the chest will leave a trailing red mark and hence the ability to write on the skin.   

== Physiological Abnormalities related to exertion == 
Da Costa’s patients have a poor aerobic capacity or low level of fitness which is not related to the lack of exercise<ref name="Lewis"/>, and they have breathing patterns and other symptoms which are not the normal response to effort<ref name='Whishaw'/><ref name="CohenLIfeSituations"/><ref name="Cohen"/><ref name="White"/><ref name="Baker"/><ref name = "Wood"/><ref name="pmid3314950"/>. They have poor diaphragm movement and reduced chest expansion at rest<ref name="Caughey"/><ref name = "Wood"/>, and during exercise training such as walking, jogging, or running "they have an easily induced oxygen debt"<ref name="White"/>, their breathing become disproportionately shallow, oxygen consumption is lower, and blood lactate levels are higher than normal<ref name="CohenLIfeSituations"/><ref name="Cohen"/><ref name="Hurst"/>, in some cases more than double<ref name="CohenLIfeSituations"/>, and as the intensity and duration of the exercise increases the physiological abnormalities increase<ref name="CohenLIfeSituations"/><ref name="Cohen"/> which is consistent with the histories and claimed disabilities of these patients<ref name="CohenLIfeSituations"/>. There is also an abnormal pooling of blood in the abdominal and peripheral veins<ref name="Mackenzie"/><ref name="nature"/><ref name="Rowe"/> , and a slow return of pulse rate to normal after exertion<ref name="Wood2"/>.

== Treatment ==
The reports of Da Costa, White, Wheeler, and Wood show that patients recovered from the more severe symptoms when removed from strenuous activity, the stressful emotional situations, or the sustained lifestyle that caused them<ref name="Hartshorne"/><ref name="Wheeler1950"/><ref name="White"/>. In many cases relapses were prevented by determining the limits of exertion and lifestyle and keeping within them<ref name="Wheeler1950"/><ref name="White"/><ref name="LewisR"> {{cite journal|title=The mitral valve prolapse epidemic: fact or fiction|journal=Transactions of the American Clinical and Climatological Association|date=1987|first=R.P.|last=Lewis|coauthors=C.F.Wooley, A.J.Kolibash and H.Boudoulas|volume=98|issue=|pages=222-236|id= |url=http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=2279723&blobtype=pdf|format=|accessdate=2008-11-17 }}</ref><ref name="Ware"/>. The physical limitations were associated with the abnormalities in respiration and circulation. Other treatments evident from the previous studies were improving nutrition<ref name="Hartshorne"/>, physique and posture,<ref name="Irritable"/> appropriate levels of exercise where possible<ref name="Mackenzie"/><ref name="Osler"/><ref name="White"/><ref name="pmid3314950"/><ref>Goudsmit EM, Howes S. "Pacing: A strategy to improve energy management in chronic fatigue syndrome", Health Psychology Update (BPS), 2008, 17, 1, 46-52</ref>, using individually designed graded exercise regimes<ref name="Lewis1918"/><ref name='Whishaw'/><ref name="Selian">{{ cite book | last = Selian | first = Neuhoff | title = Clinical Cardiology |  publisher = MacMillan | location = New York | year = 1917 | chapter = XX | pages = 255}}; cited on {{cite web |url=http://www.vlib.us/medical/dacosta.htm |title= Da Costa's Syndrome | publisher = vlib.us |accessdate=2007-12-18 |format= |work=}}</ref><ref name='Hyams'/><ref name="Wooley2"/><ref name="Wooley3"/><ref name="Hurst"/><ref name="Fleming"/> which have been proven to be effective in relieving symptoms and improving exercise tolerance in come cases<ref name='Howell'/><ref name="Harrisons"/>.
Some symptoms such as faintness can be prevented or relieved by wearing loose clothing about the neck, chest, and waist<ref name="Irritable"/><ref name="Myers"/><ref name='Howell'/>, and standing up slowly can prevent the faintness associated with postural or [[orthostatic hypotension]] in some cases<ref name="Wood2"/><ref name="Harrisons"/>, and avoiding postural changes such as stooping, or lying on the left or right side<ref name="Irritable"/><ref name = "Wood"/><ref name='Howell'/>, or the back relieved some of the palpitations and chest pains in some cases. Some of the symptoms can be relieved by laying in a recliiner chair<ref name="Selian"/>, and the chest pain can be temporarily relieved by intramuscular injection of novocaine at the site of tenderness<ref name="Wood2"/>. Also, drinking more fluids, increasing salt intake, and sleeping with the head elevated can reduce the fatigue<ref name="MacLean1940"> {{cite journal|title=Orthostatic hypotension and orthostatic tachycardia: treatment with the "head-up" bed|journal=J.A.M.A.|date=1940|first=A.R.|last=MacLean|coauthors=Allen E.V.|volume=115|issue=|pages=2162-7|id= |url=|format=|accessdate=2008-10-31 }}</ref><ref name="MacLean1944"> {{cite journal|title=Orthostatic hypotension and orthostatic tachycardia: defects in the return of venous blood to the heart|journal=American Heart Journal|date=1944|first=A.R.|last=MacLean|coauthors=Allen E.V., Magath T.B.|volume=27|issue=|pages=145-163|id= |url=|format=|accessdate=2008-10-31 }}</ref><ref name="Rowe"/>.

== Prevention ==
In his original paper J.M. Da Costa suggested that the condition tended to become chronic after a prolonged and exhausting viral infection where the person was sent back to full and demanding activity too soon. He therefore recommended that the person should be provided with sufficient rest, nourishment, and gradual physical training to achieve full strength before resuming former duties<ref name="Irritable"/><ref name="pmid3314950"/>.  Various other authors have suggested that the adoption of a moderate lifestyle and avoidance of the extremes can prevent this type of condition from developing<ref name="Wheeler1950"/><ref name="White"/><ref name="LewisR"/>, and that this general principle applies regardless of other causes and pathogenesis<ref name="Rosen"> {{cite journal|title=Is chronic fatigue syndrome synonymous with effort syndrome?|journal=Journal of the Royal Society of Medicine|date=December 1990|first=S.D. |last=Rosen|coauthors=J.C. King, J.B. Wilkinson, & P.G.F. Nixon|volume=83|issue=|pages=761-764|id= |url=|format=|accessdate=2008-03-22 }}</ref>. 

== Alternative names for Da Costa’s syndrome ==
The name of Da Costa’s syndrome has changed so often from one specialist<ref name="Baker"/><ref name="CohenLIfeSituations"/><ref name="Hurst"/>, or from one country<ref name="Volkov"/><ref name="Ware"/><ref name="lu"/>, or one year to another<ref name="CohenLIfeSituations"/><ref name="Ware"/><ref name="lu"/> that it has created confusion in the study and diagnosis of the condition,<ref name="yesteryear"/> as is evident from many research articles which mention four or five in their introduction,<ref name="Caughey"/><ref name='Whishaw'/><ref name="Cohen"/><ref name="CohenLIfeSituations"/><ref name="White"/><ref name="Wood2"/><ref name="Hurst"/><ref name="yesteryear"/><ref name="Hyperkinetic"> {{cite journal|title=The Hyperkinetic Heart|journal=The Lancet|date=October 31st. 1981|first=|last=|coauthors=|volume=318|issue=|pages=967|id= |url=|format=|accessdate=2008-11-14 }}</ref><ref name="MacLean1944"/><ref name="Wooley3"/><ref name='Howell'/><ref name='Hyams'/><ref name="titleOMIM - ORTHOSTATIC INTOLERANCE"/><ref name="lu"/>
<ref name="Harrisons"/> and from a recent website which lists what it claims are more than eighty synonyms.<ref name="thousand"/> However the title of Da Costa’s syndrome has been regarded as the preferred label by several authors because of its non-attribution and unchallengable aspect.<ref name = "Wood"/> By contrast, the labels such as [[irritable heart]] or cardiac asthenia are inappropriate because the ailment is not a form of heart disease<ref name="White"/>. Similarly [[Soldier’s heart]] is too specific<ref name="pmid3314950"/> and so it can be challenged because the vast majority of patients have never been soldiers,<ref name="White"/> and it is inappropriate when the symptoms occur in pregnant civilian women.<ref>{{cite book | last = Hamilton | first = B.E. | authorlink = | coauthors= K.J.Thomson | title = The Heart in Pregnancy and the Childbearing Age | publisher = Little, Brown and Company | date =   1941 | location = Boston | pages = | url = | doi = | id = | isbn = }}</ref><ref name = "Wood"/> Relating it to [[Post-viral fatigue syndrome]]<ref name="Harrisons"/> can be disputed because, in many cases the patient could not recall having a viral infection, and the label of [[Post-traumatic stress disorder]] (PTSD) can be challenged because many patients have not experienced preceding trauma,<ref name="Wheeler1950"/><ref name="pmid3314950"/>and the symptoms are not the same as those caused by stress<ref name="CohenLIfeSituations"/> and can have a genetic<ref name='Cohen Familial'/><ref name="Cohen"/> <ref name="Hurst"/><ref name="yesteryear"/><ref name="pmid3314950"/><ref name="titleOMIM - ORTHOSTATIC INTOLERANCE"/>, or gradual onset unrelated to stress
<ref name="Cohen"/>. [[Somatoform disorder]] refers to symptoms occurring in the absence of physical or physiological evidence to account for them [[http://dictionary.reference.com/browse/Somatoform%20Disorder]], yet Da Costa’s symptoms have been associated with multiple physical, physiological and biochemical abnormalities<ref name='Whishaw'/><ref name='Jones'/><ref name="Cohen"/><ref name="Volkov"/><ref name="pmid3314950"/><ref name='Howell'/><ref name="titleOMIM - ORTHOSTATIC INTOLERANCE"/><ref name="lu"/>, and the term [[dysautonomia]] implies a fault in the autonomic nervous system which, whilst it may be an effect, and has not been proven as a cause<ref name="White"/><ref name = "Wood"/><ref name="Wood2"/><ref name="pmid3314950"/><ref name="Stewart"/>. There are also discrepancies associated with the label of [[Hyperventilation syndrome]]<ref name="White"/><ref name="Wood2"/><ref name="pmid3314950"/><ref name="Saish"> {{cite journal|title=Hyperventilation and chronic fatigue syndrome|journal=The Quarterly Journal of Medicine|date=June 1994|first=S.G.|last=Saish|coauthors=A. Deale, W.N. Gardner, & S. Wessely|volume=87|issue=6|pages=373-374|id= |url=http://www.ncbi.nlm.nih.gov/pubmed/8140219?ordinalpos=1&itool=EntresSystem2.PEntrez.PUbmed.Pubmed_ResultsPanel.Pubmed_RVAbstractPlusDrugs1|format=|accessdate=2008-03-22 }}</ref>, and some patients with MVP have none of the symptoms of Da Costa's syndrome<ref name="pmid3314950"/><ref name="LewisR"/>. The term [[anxiety state]] implies that the patient is in a constant state of anxiety, yet many patients appear calm and are rarely affected by anxiety<ref name="Cohen"/><ref name="LewisR"/><ref name="Rowe"/>, and the term [[anxiety disorder]] can be disputed because the symptoms are not the same as those produced by anxiety<ref name="CohenLIfeSituations"/><ref name="White"/>and they don’t develop any abnormal incidence of other diseases such as [[peptic ulcer]]s or [[asthma]] which have been previously, and erroneously attributed to anxiety<ref name="Wheeler1950"/><ref name="pmid3314950"/>and labelled as psychosomatic<ref name="Hurst"/>. Similarly the condition cannot be regarded as an exercise phobia because many patients were capable of strenuous marching prior to developing the condition<ref name="Irritable"/> or were formerly good athletes<ref name='Jones'/>. However, by referring to the ailment as Da Costa’s syndrome it can be said that it may be related to anxiety, excessive physical or emotional stress, post-viral causes, and unknown causes etc. The symptoms can include [[orthostatic hypotension]] and postural tachycardia<ref name="Rowe"/><ref name="lu"/> but those terms are not appropriate as labels because they don’t account for the other symptoms. Da Costa’s could be referred to as a type of [[Chronic fatigue syndrome]],<ref name="White"/><ref name="Rosen"/><ref name="nature"/><ref name="Ware"/><ref name="titleOMIM - ORTHOSTATIC INTOLERANCE"/><ref name="Stewart"/><ref name="Wooley4"/><ref name="lu"/><ref name="Harrisons"/> because chronic fatigue is the main symptom, but the other five typical symptoms distinguish it from the general term [http://www.cfids-cab.org/MESA/ccpc.html], and from other types of CFS<ref name="Ware"/>.

== Differential Diagnosis ==
The condition needs to be distinguished from [[angina]] heart disease (angina pectoris), [[mitral valve prolapse syndrome]]<ref name="Wooley2"/>, [[hyperventilation syndrome]], [[hyperkinetic heart]], [[cardiophobia]]<ref name="pmid3314950"/>, normal tiredness<ref name="Baker"/><ref name='Cohen Familial'/> the normal symptoms of exertion<ref name="Baker"/><ref name="Cohen"/><ref name="White"/>, exercise phobia, [[panic attack]]s, [[anxiety state]], and [[depression]], and  other similar syndromes such as the the [[post-traumatic stress disorder]]s and the numerous [[post-war syndrome]]s.<ref name="pmid3314950"/>. It also needs to be distinguished from other types of [[orthostatic hypotension]] <ref name="Rowe"/><ref name="Stewart"/><ref name="lu"/>
or [[chronic fatigue syndrome]]s<ref name="Wooley4"/>
, which involve separate or different, or additional symptoms. However many patients with Da Costa’s syndrome also have such problems as a coincidence or as a result of the ailment. For example patients who have symptoms similar to heart disease, often develop a fear of heart disease (cardiophobia)<ref name="Wood2"/><ref name="pmid3314950"/>
Also note that Da Costa’s syndrome involves a set of six classic symptoms, and needs to be distinguished from  conditions that involve only one or two symptoms<ref name="Hurst"/>. For example [[hyperkinetic heart]] may occur on its own as a single symptom, or it may be part of the set of six in a Da Costa’s patient<ref name="Hyperkinetic"/><ref name="pmid3314950"/>. Similarly a person who only has a dual combination of the left-sided chest pain and palpitations does not necessarily have Da Costa's syndrome.
Also, characteristically Da Costa’s syndrome involves fatigue which includes both an impaired capacity for exertion<ref name="Lewis1918"/><ref name="Osler"/><ref name="Harrisons"/>, and secondly, an abnormal pattern of tiredness<ref name="Baker"/>. Therefore, if patients do not have difficulty with exertion they do not have Da Costa’s syndrome,<ref name="Irritable"/> e.g. a person who complains of abnormal [[tiredness]] but participates in vigorous sport does not have Da Costa’s syndrome.

== Related Conditions ==
::[[Chronic Fatigue Syndrome]]
::[[Postural Orthostatic Tachycardia Syndrome]] <ref name="Raj"/>
::[[Soldier’s Heart]]
::Chest Wall Syndrome
::Costochondritis - left-sided chest pain
::Sigh Syndrome
::[[Exercise Intolerance]]
::[[Mitral Valve Prolapse Syndrome]]

== Portrait of a typical Da Costa’s syndrome patient ==
<ref name="Wood2"/>
Also [http://users.chariot.net.au/~posture/DaCostaSyndromePainting.html#anchor99859]

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