Combined dipyridamole and dobutamine echocardiography in myocardial hibernation: comparison with thallium uptake in patients after percutaneous transluminal coronary revascularization under circulatory support.

ABSTRACT

OBJECTIVE: To investigate the specificity and sensitivity of the combination of dipyridamole and dobutamine echocardiography for predicting functional recovery in patients with reduced ventricular function after coronary angioplasty. METHODS: Twenty-five patients, mean (SD) age 60.8 (10) years, with previous myocardial infarction (> 3 months), angiographically assessed coronary artery disease, and resting regional dysfunction (left ventricular ejection fraction < 35%) were studied. They underwent rest-redistribution thallium Tl-201 single photon emission computed tomography, and low-dose pharmacologic stress echocardiography with dobutamine (up to 10 microg/kg per minute), ultra low-dose dipyridamole (0.28 mg/kg over 4 minutes), and combined dipyridamole-dobutamine administration. RESULTS: The rate of agreement between Tl-201 and stress echo was 59% for dipyridamole, 62% for dobutamine, and 71% for combined dipyridamole-dobutamine (P <.05 vs dipyridamole and vs dobutamine). Combined dipyridamole-dobutamine showed a higher sensitivity (89%) than Tl-201, dobutamine, or dipyridamole (84%, 78%, and 80%). Specificity was lower for functional recovery prediction with Tl-201 (60%) compared with dobutamine (89%), dipyridamole (90%), and combined dipyridamole-dobutamine (91%). CONCLUSION: Thallium is more sensitive than dipyridamole or dobutamine; the sensitivity gap is filled with combined dipyridamole-dobutamine. Pharmacologic stress echocardiography is more specific than Tl-201 scintigraphy.