Wiktionary
bigeminy
n. (context pathology English) The alternation of one normal heartbeat and one premature heartbeat
Wikipedia
Bigeminy
Bigeminy (Latin: bi-two, gemini-twins) is a descriptor for a heart arrhythmia in which there is a continuous alternation of long and short heart beats. Most often this is due to ectopic heart beats occurring so frequently that there is one after each sinus beat, typically premature ventricular contractions (PVCs). For example, a sinus beat is shortly followed by a PVC, then followed by a pause. The normal beat then returns, only to be followed by another PVC.
Usage examples of "bigeminy".
Rosenberg himself had suffered a so-called bigeminy rhythm, in which both sides of the heart contracted at once.