Da Costa's syndrome

Lore & Background

Da Costa's syndrome was first systematically described by Jacob Mendes Da Costa in 1871 after studying 300 soldiers during the American Civil War. He noted that symptoms often developed after a bout of fever or diarrhoea, and that the pulse was greatly influenced by position. Earlier observers, including Earl de Grey and Henry Harthorme, had noted similar symptoms in British and American soldiers, attributing them to heavy equipment, overexertion, and poor rest. Da Costa's work gave the condition a name and a physiological explanation, though it was later recharacterized as a neurosis.

Reader's Guide

Da Costa's syndrome represents a pivotal moment in medical history where a set of symptoms originally attributed to organic heart disease was gradually recognized as having non-cardiac origins. The condition was treated with digitalis, a cardiac drug, and bed rest. By the mid-20th century, it was reclassified as a psychiatric disorder, and by the 1970s it appeared in the ICD-9 under somatoform autonomic dysfunction. Modern understanding suggests it encompasses several unrelated disorders, including myalgic encephalomyelitis/chronic fatigue syndrome, postural orthostatic tachycardia syndrome (POTS), and mitral valve prolapse syndrome. The term is now obsolete, but its history illustrates the evolution of medical classification and the challenges of diagnosing conditions with overlapping physical and psychological symptoms.

Did You Know?

• Da Costa's syndrome was originally thought to be a cardiac condition and treated with digitalis, a precursor to modern cardiac drugs.
• The orthostatic intolerance observed by Da Costa has since been found in patients with myalgic encephalomyelitis/chronic fatigue syndrome, POTS, and mitral valve prolapse syndrome.
• During World War I, Sir Thomas Lewis studied soldiers with 'disordered action of the heart' and found most did not have structural heart disease.
• The condition has been called by many names, including soldier's heart, cardiac neurosis, effort syndrome, and neurocirculatory asthenia.

The Clinical Picture: A Heart That Looked Fine but Felt Broken

Da Costa's syndrome presented as a bewildering cluster of symptoms that closely mimicked cardiac disease. Patients reported fatigue with even modest exertion, weakness triggered by minor activity, breathlessness, palpitations, profuse sweating, and chest pain—frequently on the left side. A subset also experienced orthostatic intolerance, meaning their symptoms worsened with shifts in body position. In his 1871 study, Da Costa described a typical case: a soldier on active duty for months who contracted a bout of fever or diarrhoea, returned to service after a brief hospital stay, and then found he could no longer keep pace with his comrades. He grew breathless, dizzy, and plagued by palpitations and chest pains, yet on later examination appeared generally healthy. The pulse was notably and rapidly affected by posture—stooping or reclining produced dramatic changes. This disconnect between how the patient felt and what the physician could observe made the condition especially puzzling to the medical community of the era.

From the Battlefield to the Textbook: How the Syndrome Was Discovered

The constellation of symptoms now associated with Da Costa's syndrome surfaced repeatedly across military conflicts well before it received its eponymous label. During the Crimean War and the American Civil War, similar symptom clusters were documented among troops. In the 1860s, Earl de Grey presented four reports on British soldiers whose complaints he attributed to the constriction caused by tightly strapped knapsacks. Henry Harthorne, observing Civil War soldiers in 1864, blamed prolonged overexertion compounded by inadequate rest and nutrition. Arthur Bowen Myers of the Coldstream Guards, writing in 1870, also pointed to military accoutrements and introduced the terms neurocirculatory asthenia and cardiovascular neurosis. It was Jacob Mendes Da Costa who, in 1871, published a study of 300 soldiers that crystallized the clinical picture, adding that the condition often followed a bout of fever or diarrhoea and that body position dramatically influenced the pulse. He termed it "irritable heart," though the more popular label "soldier's heart" was already circulating. Usage of the name "Da Costa's syndrome" peaked in the early twentieth century before gradually fading from medical parlance.

The Diagnostic Reckoning: From Cardiac Ailment to a Historical Umbrella

What was once managed as a genuine heart condition has undergone a dramatic reclassification over the past century. Originally treated with digitalis, the syndrome was recategorized as psychiatric by the time the ICD-9 was published in the 1970s. In ICD-10 it appeared under code F45.3, initially as a somatoform disorder of the heart and cardiovascular system, later refiled under the broader heading of somatoform autonomic dysfunction. Yet the term has largely fallen out of common medical use, superseded by more specific diagnoses. The orthostatic intolerance Da Costa noted has since been identified in patients with myalgic encephalomyelitis/chronic fatigue syndrome, postural orthostatic tachycardia syndrome, and mitral valve prolapse syndrome. In the twenty-first century, that orthostatic intolerance is classified as a neurological condition, and exercise intolerance has been linked to numerous organic diseases. The syndrome thus represents a historical diagnostic umbrella under which several distinct pathologies were once lumped together before modern medicine could separate them.

Rest, Posture, and Foxglove: How Physicians Managed the Condition

Therapeutic approaches to Da Costa's syndrome ranged from simple rest to pharmacological intervention. Da Costa's own 1871 report showed that patients with the most severe symptoms recovered once removed from the strenuous activity that had precipitated the condition. A reclined position and enforced bed rest proved most beneficial. Additional measures drawn from earlier studies included improving physique and posture, maintaining appropriate exercise where feasible, wearing loose clothing around the waist, and avoiding certain postural changes—stooping, or lying on the left or right side, or on the back in some cases—which could relieve palpitations and chest pains. Rising slowly from a seated or lying position helped prevent the faintness associated with orthostatic hypotension. When medication was deemed necessary, digitalis was the agent of choice. Derived from the foxglove plant, these glycosides act as sodium-potassium ATPase inhibitors; at the time they were prescribed primarily for their heart-rate-lowering effect in patients suffering from palpitations, though their modern pharmacological profile also includes increasing stroke volume.