Pulsus bigeminus

Overview
Pulsus bigeminus is a cardiovascular phenomenon characterized by groups of two heartbeats close together followed by a longer pause. The second pulse is weaker than the first. It is caused by premature contractions, usually of the ventricles, after every other beat.

Differential diagnosis of causes of pulsus bigeminus
It can be a sign of hypertrophic obstructive cardiomyopathy or of many other types of heart disease. It can also be an innocent and passing phenomenon.