Evaluation and Management of Loud S2 with Ejection Click

Key Diagnostic Considerations

A loud S2 with an ejection click most commonly indicates pulmonary hypertension or congenital heart disease, and requires immediate transthoracic echocardiography as the first-line diagnostic test, as recommended by the American College of Cardiology 1, 2
The American Heart Association suggests that the combination of a loud S2 and ejection click narrows the differential diagnosis to pulmonary hypertension, bicuspid aortic valve, pulmonary stenosis, or atrial septal defect 3
Bicuspid aortic valve generates an aortic ejection click at 0.13 seconds from the Q wave, though typically A2 is preserved unless stenosis is severe, according to the American College of Cardiology 3
Atrial septal defect presents with fixed split S2 and may have associated ejection sounds from increased flow across the pulmonary valve, as noted by the American Heart Association 3, 4

The American College of Cardiology recommends ordering transthoracic echocardiography immediately for evaluation of abnormal heart sounds and suspected valvular disease 1, 2
The echocardiogram must assess valve morphology, presence of intracardiac shunts, right ventricular size and function, pulmonary artery pressures, and left ventricular size and function, as suggested by the American College of Cardiology 2, 3, 4

If pulmonary hypertension is confirmed, investigate the underlying cause and refer to a pulmonary hypertension specialist for targeted therapy consideration, as recommended by the American College of Cardiology 1
If congenital heart disease is identified, follow-up echocardiography is necessary, and consideration of closure or repair may be required, according to the American Heart Association 3, 5
If L-TGA is suspected, recognize the presentation with single loud S2 and manage heart failure with standard medications, as noted by the American Heart Association 3

The American College of Cardiology recommends against performing exercise testing in symptomatic patients with suspected severe stenotic lesions, but considers it in asymptomatic patients to elicit exercise-induced symptoms 5