[Myocardial contrast echocardiography for the follow-up after percutaneous transluminal coronary angioplasty].

Myocardial contrast echocardiography was performed, before and after successful elective percutaneous transluminal angioplasty (PTCA) of a main coronary artery, in 35 patients (31 men, 4 women; mean age 56 +/- 6 years). After intracoronary injection of microbubbles-containing 2 ml iopromide, contrast half-life (t/2) and maximal echo-intensity (Imax) in the myocardial region supplied by the target vessel were measured. While t/2 decreased from 8.3 +/- 5.4 s to 5.7 +/- 3.3 s (P less than 0.0002), mean Imax remained unchanged (27.4 +/- 10.7 vs 26.1 +/- 10.1 grey value units). Repeat cardiac catheterization with contrast echocardiography was performed a mean of 37 weeks (7-53) later in 13 of 35 patients with optimal echo image quality. Re-stenosis of at least 75% was demonstrated in six patients, while in seven vessel diameter had decreased by less than 30%. In all patients with re-stenosis t/2 had increased by about 20 to 100% of the initial value. It was always over 5 s (mean 6.2 +/- 1.6 s before, 4.7 +/- 1.7 after PTCA, and 6.2 +/- 1.2 s at the end of the follow-up). In one patient a prolonged t/2 persisted due to vessel dissection. Mean t/2 remained unchanged in patients without re-stenosis (5.6 +/- 2.1 s before, 3.5 +/- 1.15 s immediately after PTCA, and 3.6 +/- 1.25 s at the follow-up examination). These data suggest that contrast half-life is suitable for demonstrating changes in myocardial perfusion after PTCA.