Transient dobutamine-mediated pulsus alternans.

Pulsus alternans, alternating weak and strong beats occurring in a heart beating at a constant rate, has most often been reported in patients with severe, end-stage heart failure. This patient with New York Heart Association functional class I heart failure developed pulsus alternans during the inotropic stimulation of dobutamine that subsequently resolved in a time course consistent with dobutamine clearance. Thus, in the setting of mildly impaired myocardial contractility, the inotropic stimulus of dobutamine may precipitate the development of reversible pulsus alternans.