Pyruvate-enhanced cardioprotection during surgery with cardiopulmonary bypass

Abstract

Objectives To determine whether pyruvate-fortified cardioplegia solution provides cardioprotection superior to lactate-based cardioplegia solutions in patients undergoing elective coronary revascularization, with specific attention to post-surgical recovery of left ventricular performance as well as biochemical markers of ischemic injury. Design Prospective, randomized, semi-blinded human trial. Setting Community-based academic medical center. Participants Thirty adult patients undergoing elective coronary artery bypass graft surgery. Interventions Patients were randomized to two 4:1 blood cardioplegia solutions, one pyruvate enhanced and the other lactate based. Hemodynamic and laboratory variables were measured in all patients at pre-cross-clamp, post-cross-clamp, and 4, 6, 8, and 12 hours after bypass. Measurements and main results Relative to lactate-based cardioplegia, pyruvate-fortified cardioplegia sharply increased left ventricular stroke work at 4 to 12 hours after bypass ( p < 0.001), lowered coronary sinus troponin I and creatine phosphokinase-MB activities 67% ( p < 0.001) and 53% ( p < 0.01), respectively, and increased coronary sinus hemoglobin O 2 saturation 18% ( p < 0.001). Ten patients treated with lactate cardioplegia required β-adrenergic inotropic support postbypass, but only 4 pyruvate-treated patients required β-adrenergic support ( p = 0.067). Pyruvate cardioplegia shortened postsurgery hospitalization from 6.3 ± 0.3 to 5.2 ± 0.1 days ( p < 0.002). Conclusions Pyruvate-fortified cardioplegia mitigated myocardial injury during coronary artery bypass surgery and facilitated postsurgical recovery of cardiac performance. Thus, pyruvate-enhanced cardioplegia may provide cardioprotection superior to lactate-based solutions during surgical cardiac arrest.