MYOCARDIAL PROTECTION DURING CORONARY-ARTERY BYPASS GRAFT-SURGERY - ARANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY WITH TRIMETAZIDINE

We conducted a randomized, double-blind, placebo-controlled study to a ssess the cardioprotective effects of trimetazidine (TMZ), an antiisch emic drug, on left ventricular function using transesophageal echocard iography (TEE) after coronary artery bypass grafting (CABG). Forty pat ients undergoing elective CABG received either TMZ or a placebo (PCB). The primary measures of efficacy were serial measurements of fraction al area change (FAG), percent of systolic wall thickening (SWT), and m alonedialdehyde (MDA) production. The two groups were similar for the following variables: number of vessels revascularized (2.5 +/- 0.2 in the TMZ group and 2.8 +/- 0.1 in the PCB group), duration of aortic cl amping (46 +/- 4 min in the TMZ group and 48 +/- 3 min in the PCB grou p), and bypass time (63 +/- 4 min in the TMZ group and 70 +/- 4 min in the PCB group). FAC increased by 12% in both groups 20 min after aort ic unclamping (P < 0.05) and remained above the initial value at the s ixth postoperative hour. SWT was 23.8% +/- 1.6%, 25.4% +/- 1.9%, then, 21.6% +/- 1.5% in the TMZ group and 22.8% +/- 1.6%, 23.8% +/- 1.4%, t hen 22.3% +/- 1.6% in the PCB group, after induction of anesthesia and 1 and 6 h after aortic unclamping (not significant). MDA increased by 24% in the PCB group and 25% in the TMZ group 20 min after aortic unc lamping (P < 0.01). Lactate levels were lower in the TMZ group (P < 0. 05) and patients from the TMZ group received less intravenous calcium before aortic clamping (P < 0.02) and less calcium channel entry block ing drugs in the early phase after aortic unclamping (P < 0.01) compar ed to the PCB group. We conclude that in patients with good preoperati ve ejection fraction undergoing CABG, TMZ as administered did not demo nstrate clinically significant cardioprotective effects on left ventri cular performance and lipid peroxidation compared to PCB.