Pulsus alternans

An arterial pulse characterized by regular rhythm with beat-to-beat alternation of strong and weak pulse amplitude, reflecting alternating strong and weak ventricular contractions. Typically associated with severe ventricular systolic dysfunction, heart failure, cardiomyopathy, coronary artery disease, aortic stenosis, right ventricular strain, pulmonary embolism, pulmonary hypertension, and pericardial effusion.