Pulsus alternans describes an arterial pulse waveform that shows alternating strong and weak beats despite a regular rhythm. Either discovered during physical examination or catheterization, pulsus alternans indicates severe left ventricular (LV) dysfunction and poor prognosis. There has been considerable debate about the underlying mechanism. We present a tracing which depicts a classic example of pulsus alternans and gives some clues about its initiation mechanism.

Pulsus alternans, defined by an arterial pulse alternating between strong and weak beats, often signify severe left ventricular dysfunction. Detectable on physical examination or by echocardiography, this phenomenon highlights substantial cardiac compromise. We discuss a case involving a 59-year-old male with non-ischemic cardiomyopathy who was admitted for acute congestive heart failure. The echocardiogram revealed severe left ventricular dysfunction with systolic and diastolic beat-to-beat variations in blood flow on Doppler, a phenomenon known as Doppler alternans. Notably, these echocardiographic findings preceded any clinical signs, leading to a timely escalation in care. This case emphasizes the critical role of echocardiography in assessing ventricular function and providing prognostic insights that can influence management strategies.

A 58-year-old man presented with worsening dyspnea. Electrocardiogram showed variation in T-wave amplitude occurring every other beat. Transthoracic echocardiography revealed a severe aortic stenosis with beat-to-beat variation in stroke volume, suggestive of pulsus alternans. Recognition of pulsus alternans is important because it is considered a marker of poor prognosis.

Pulsus alternans has been considered a sign of poor prognosis in patients undergoing treatments for heart failure. However, it may be overlooked in patients with intra-aortic balloon pumps (IABPs). The use of IABP and ivabradine for a β-blocker introduction in a patient with dilated cardiomyopathy (DCM) and pulsus alternans and its consequence have never been reported.

Pulsus alternans, not to be confused with pulsus paradoxus or electrical alternans, is an arterial pulse with alternating strong and weak beats. Systolic pressures will vary from beat-to-beat as identified on physical exam and echocardiogram. Pulsus alternans is found in the setting of severe ventricular dysfunction and other forms of cardiac pathology. Variations of pulsus alternans include left ventricular alternans, right ventricular alternans, and biventricular alternans. The treatment and clinical outcomes for pulsus alternans vary depending upon the underlying causative etiology, though its presence generally suggests a poor prognostic outlook.[1]

Objective Spontaneous mechanical alternans (MA), or pulsus alternans, has been observed in heart failure patients with hypertension or tachycardia for 150 years and is considered a sign of a poor prognosis. However, in some dilated cardiomyopathy (DCM) patients with MA, optimal medical therapy (OMT) brings left ventricular reverse remodeling (LVRR), a preferable prognostic indicator. This study examined the probability of LVRR in DCM patients with spontaneous MA and whether or not LVRR can be predicted by the baseline blood pressure or heart rate. Methods We conducted a single-center, retrospective observational study of newly diagnosed DCM patients from January 2017 to December 2020. Results Thirty-three newly diagnosed DCM patients were retrospectively examined. Spontaneous MA was observed during diagnostic cardiac catheterization in at least 1 of the pressure waveforms of the aorta, left ventricle, pulmonary artery, or right ventricle in 10 patients (30%) (MA-group). LVRR after OMT was achieved roughly equally in the MA group (6 of 10, 60%) and the non-MA group (12 of 23, 52%). In the MA group, those who achieved LVRR had a significantly higher baseline systolic aortic pressure (more than 120 mmHg in all 6 patients) than those who did not, although the baseline heart rate did not show a significant correlation with LVRR. In contrast, in the non-MA group, LVRR was unrelated to the baseline aortic pressure or heart rate. Conclusion The probability of LVRR in newly-diagnosed DCM patients with spontaneous MA was similar to that in those without spontaneous MA. Spontaneous MA may not necessarily be a sign of a poor prognosis if observed in patients with a preserved blood pressure.

Pulsus alternans is characterized by alternating strong and weak beats, and occurs with failing hearts. Left ventricular pulsus alternans is known to occur with ischemic heart disease, valvular heart disease, and outflow tract obstructions. Isolated right ventricular (RV) pulsus alternans is a rare entity. We report the case of a 51-year-old male patient who presented with inferior wall myocardial infarction and cardiogenic shock. He was diagnosed to have an isolated tricuspid regurgitation alternans signifying severe RV dysfunction. The patient was resuscitated and treated with primary percutaneous intervention to the right coronary artery. We also review the literature associated with RV pulsus alternans and its mechanisms.

Pulsus alternans is a rare condition characterized by alternation between strong and weak pulses during regular heart rhythm. Although pulsus alternans occurs mostly in severe heart failure, it can also be seen in other conditions that alternate ventricular contraction such as rapid tachycardia and extrasystole. Here, we report the case of a patient with peripartum cardiomyopathy who developed worsening pulsus alternans after a premature ventricular contraction.