Post-extrasystolic potentiation recruits incremental contractile reserve of dyssynergic myocardium during dobutamine stress testing: evidence by pulsed wave tissue Doppler imaging.

Dobutamine stress echocardiography is an established diagnostic method for the detection of myocardial viability in patients with severe left ventricular dysfunction([1]). The presence of viable myocardium identifies patients who will benefit from coronary revascularization, by improving both functional capacity and long-term survival. Occasionally, dobutamine infusion has been combined with other stressors, such as post-extrasystolic potentiation, in order to improve accuracy. The contractile reserve after combined dobutamine infusion and post-extrasystolic potentiation can be quantified by pulsed wave tissue Doppler imaging. We describe a patient with severe left ventricular dysfunction, in which pulsed wave tissue Doppler imaging allowed to demonstrate that post-extrasystolic potentiation superimposed on dobutamine infusion is able to further recruit contractile reserve, as compared to dobutamine infusion alone. A nuclear scan assessing glucose utilization was used as a reference.