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We studied left ventricular perfusion and motility in 37 patients with coronary artery disease and disturbances of parietal motility, aged 57 +/- 9 years old, before and after revascularization. Perfusion was assessed with dipyridamole-tc99m MIBI SPECT and motility was assessed with two dimensional echocardiography with amrinone. Myocardial segments were defined as normal, viable or necrotic in both studies. Eighteen subjects were subjected to angioplasty and 19 to coronary bypass surgery. Submitted SPECT and echocardiography were repeated 64 +/- 15 and 69 +/- 23 days after revascularization respectively. The concordance between SPECT and echocardiographic pre-revascularization diagnosis was 60.1% Eighty one percent of segments considered viable with SPECT and 71% thus considered with echocardiography improved after revascularization. Likewise, 50% of segments considered necrotic with SPECT and 68% of segment thus considered with echocardiography did not improve. It is concluded that although there is a good concordance between both methods, they have limitations on the study of myocardial viability and should be considered as second choice.

We report two male patients aged 50 and 55 years old with coronary artery disease who were treated with surgical revascularization and angioplasty respectively. To assess viable and ischemic myocardial territories, they were studied before and after revascularization with radionuclide perfusion SPECT with Tc99m-Sestamibi under Dipyridamole and with 2-D echocardiography at baseline and after the use of amrinone. Improvement in relative perfusion on SPECT and wall motion on 2-D echocardiography indicated tissue recovery.

It has been reported recently that 5-amino-34,4'-bipyridine-6(1H)-one is a new positive inotropic agent that appears to offer significant advantages over the cardiac glycosides. The effects of this agent were studied in a modified heart-lung preparation which allows the measurement of coronary flow and oxygen consumption in addition to a controlled study of cardiac contractility. In two models of cardiac insufficiency the administration of 5 mg amrinone caused a marked increase in cardiac output and a considerable decrease in left atrial pressure with complete reversal of the failure. In addition, the drug produces a 78% increase in coronary flow. Amrinone produces in these preparations a proportionally larger increase in cardiac output than in oxygen consumption, thus this agent increases cardiac efficiency. These results suggest that this new compound could be very useful in the treatment of cardiac insufficiency in congestive heart failure.

The hemodinamic effects of Amrinone, bipiridine derivate with positive inotropic effects in animals, were studied on eight patients under right and left heart catheterization. The cardiac index, stroke volume, dP/dt and stroke work index were increased; the pulmonary pressure and the left ventricle end diastolic pressure were decreased all with statistical significant values. There were no changes in mean aortic pressure. These effects are mainly due to an increase in contractility and, partially, to vasodilation and tachycardia. The intrinsic mechanism of action of this compound is not known. Its place in cardiac therapy must be established with additional clinical investigations.