Evaluation of myocardial perfusion and function by technetium-99m methoxy isobutyl isonitrile before and after percutaneous transluminal coronary angioplasty. Preliminary results.

Myocardial perfusion and function were evaluated with Tc-99m MIBI myocardial scintigraphy before and after percutaneous angioplasty in six patients. In addition to conventional stress-rest images (3 projections: 45 degrees left anterior oblique, anterior, and left lateral), gated images were obtained at rest and during stress before and after angioplasty. Improvement in myocardial perfusion after angioplasty was demonstrated in all patients. The increase from rest to stress of radionuclide fractional shortening (an index of global left ventricular function computed on gated images) was greater after angioplasty than before (9% +/- 7% versus--0.5% +/- 8%, respectively, p < 0.05). Systolic wall thickening (an index of regional left ventricular function) showed a significantly greater rest-to-stress increase after angioplasty than before it in the regions supplied by treated vessels. Thus, Tc-99m MIBI myocardial scintigraphy is capable of evaluating myocardial perfusion and function.