Myocardial cytoprotection during percutaneous transluminal coronary angioplasty.

Transluminal coronary angioplasty (PTCA) is a well defined controlled model inducing regional myocardial ischaemia in man. Direct cardiac anti-ischaemic effects of anti-anginal drugs can be assessed by intracoronary injection of small doses which do not affect systemic parameters. Trimetazidine (TMZ) has recently been shown to improve anginal symptoms without modifying haemodynamic variables. A randomized, double-blind, placebo-controlled trial was conducted in 20 patients to study the effects of TMZ on the severity of myocardial ischaemia during PTCA of the left anterior descending coronary artery. Five minutes after a first successful dilation (D0), a control balloon inflation (D1) was performed until onset of ischaemic signs on both the intracoronary (i.c.) and precordial ECG. Two minutes later, patients received either trimetazidine 6 mg or placebo i.c. Another inflation (D2) was performed 5 min after D1. No differences were found between the two groups regarding responses in heart rate, systemic and i.c. pressures during the study. TMZ decreased maximum ST segment shift at D2 as compared to D1 (0.8 +/- 0.1 vs 1.4 +/- 0.3 mV, P = 0.023) and delayed its onset (46 +/- 4 vs 36 +/- 5 s, P = 0.024). TMZ also decreased maximum T wave changes (1.06 +/- 0.24 vs 2.19 +/- 0.3 mV, P = 0.001), and significantly reduced the area under the curve (AUC:mV.s-1) of the i.c. ST segment and T wave changes during balloon inflation (P = 0.002 and P < 0.001 respectively). Placebo had no effect on any of these parameters.(ABSTRACT TRUNCATED AT 250 WORDS)