Nitroglycerin Cardioplegia Effect on Coronary Artery Targets in Bypass Grafting

Abstract

Background: Coronary artery targets are essential for referral acceptance to achieve complete coronary revascularization. Patients and Methods: A prospective double-blind study was carried out to determine whether the addition of nitroglycerin to cold blood hyperkalemic cardioplegia would optimize the size and number of coronary artery targets during conventional coronary bypass grafting. Results: A total of 60 adult elective coronary artery bypass grafting cases were enrolled; 30 in group N (nitroglycerin added to cardioplegia) and 30 in group C (controls). The number of bypassed vessels ranged from 2 to 5 with a mean of 3.63. In a comparison between groups N and C, the average number of grafts per patient (3.67 ± 0.77 vs. 3.67 ± 0.92); the average performed/predicted ratio for coronary artery bypass grafting targets (0.96 ± 0.18 vs. 1.02 ± 0.31); and the average intraoperatively measured luminal diameter of the bypassed coronary artery targets (1.55 ± 0.23 vs. 1.51 ± 0.23) showed no significant difference between the two groups, except that the luminal diameter of the obtuse marginal II artery was larger in group C compared to group N (p = 0.037). Conclusions: The addition of nitroglycerin to cardioplegia did not show any benefit, either quantitatively or qualitatively, for optimizing coronary artery bypass grafting targets.

Key words

coronary artery bypass grafts surgery - CABG - myocardial protection/cardioplegia (incl. metabolism) - nitroglycerin

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