An athlete may collapse after exertion. This may be caused by a variety of conditions.

Exercise-associated collapse may be associated with:

(1) hypertrophic cardiomyopathy

(2) coronary artery anomaly

(3) malignant ventricular arrhythmia

(4) myocarditis

(5) atherosclerotic cardiac disease

(6) exercise-induced anaphylaxis

(7) exercise-associated hyponatremia

(8) hypoglycemia

(9) dehydration

(10) heat illness

(11) hypothermia

(12) cerebral encephalopathy

(13) intracranial aneurysm

(14) drug-induced hyperthermia

(15) sickle cell disease

(16) Marfan's syndrome

(17) rhabdomyolysis

(18) asthma or exercise-associated bronchospasm

(19) exercise-associated postural hypotension

(20) no obvious underlying cause


The reason for collapse when there is no cause identified is uncertain. Some possible explanations include:

(1) the reflex of Barcroft and Edholm (onset of low right atrial pressure triggers a skeletal muscle vasodilator reflex resulting in sudden hypotension)

(2) other cardiac baroreflex

(3) cerebral hypoperfusion due to peripheral pooling of blood.

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