Pulsus alternans is a physical finding with arterial pulse waveform showing alternating strong and weak beats.

Other explanation is due to the heterogeneity of the refractory period between the healthy and diseased myocardial cells.

[citation needed] Pulsus alternans is diagnosed by first palpating the radial or femoral arteries, feeling for a regular rhythm but alternating strong and weak pulses.

If alternating loud and soft Korotkoff sounds are heard, pulsus alternans is indicated.

[4] D. H. Lawrence describes pulsus alternans in his novel, Sons and Lovers: Then he felt her pulse.