Left Ventricular Outflow Tract Obstruction

Left ventricular outflow tract obstruction is suggested by his male sex, the history of a murmur during childhood and episodes of exertional syncope.

Etiology and Severity

The patient’s history also provides clues to the etiology and severity.

A congenital lesion is suggested by the history of a murmur since childhood. The lesion is likely severe when exertional syncope occurs. With significant outflow tract obstruction, cerebral perfusion is reduced during exercise, as arterial pressure declines due to systemic vasodilatation in the presence of limited ability to increase cardiac output. Arrhythmias may also contribute to the syncope of outflow obstruction.