Pulsus alternans determined by biventricular simultaneous systolic time intervals

Area of Science:

• Cardiology
• Cardiovascular Physiology

Background:

• Pulsus alternans is a beat-to-beat variation in pulse amplitude.
• Its presence in systemic and pulmonary circulations in heart failure requires further investigation.
• Congestive cardiomyopathy is a common cause of heart failure.

Purpose of the Study:

• To determine the presence of unilateral or bilateral pulsus alternans in systemic and pulmonary circulations in heart failure patients.
• To estimate the prevalence of pulsus alternans in congestive cardiomyopathy.
• To explore the relationship between ventricular premature complexes (VPCs) and pulsus alternans.

Main Methods:

• Simultaneous dual echocardiograms were used to measure left- and right-sided systolic time intervals in 36 adult heart failure patients.
• Echophonocardiographic records of 100 patients with congestive cardiomyopathy were reviewed.
• Pulsus alternans was assessed for its presence and triggers, including VPCs.

Main Results:

• Pulsus alternans was observed in 13 out of 36 heart failure patients (36%).
• Left-sided alternans occurred in seven, right-sided in one, and bilateral in six patients.
• Persistent alternans was found in 10 patients and VPC-induced alternans in seven of the 100 congestive cardiomyopathy patients.
• VPCs precipitated alternans when the early beat had an abbreviated ejection time.

Conclusions:

• Pulsus alternans can be unilateral or bilateral in the systemic and pulmonary circulations of heart failure patients.
• The prevalence of pulsus alternans in congestive cardiomyopathy is significant.
• VPCs are a common trigger for pulsus alternans in this population.
• No difference in disease severity was found between patients with and without pulsus alternans.