It is a pulse wave with a normal beat followed by a premature beat and a compensatory pause, occurring in rapid succession, resulting in alternation of the strength of the pulse Since the second beat is an ectopic, there is a pause after it.
Pulses bigeminus is commonly found in Digitalis toxicity and 3 : 2 heart block.
In pulsus trigeminus, three beats and a pause recur in a regular fashion.
Differential diagnosis of pulsus bigeminus is pulses alternans.
In pulsus alternans the compensatory pause is absent,
But in pulsus bigeminus, compensatory pause is present. Pulsus bigeminus is a sign of digitalis toxicity.
