Revascularization of dysfunctional but viable myocardium needs to be careful about postoperative rhythm disturbance after off-pump coronary artery bypass grafting: an uncontrolled observational retrospective clinical study

Myocardial viability is one of important factors to determine clinical outcomes after off-pump coronary artery bypass grafting. We hypothesized that the revascularization of nonviable myocardium might show the different features of myocardial reperfusion postoperatively as compared with viable myocardium. Patients who underwent off-pump coronary artery bypass grafting for 2 years were retrospectively reviewed. Viable group (V group, n=159) and nonviable group (N group, n=24) were divided using preoperative single photon emission-computed tomography. The postoperative complication was evaluated by 1) occurrence of rhythm disturbance (atrial fibrillation/flutter or ventricular tachycardia), 2) use of continuous epinephrine, and 3) intra-aortic balloon pump insertion. Intubation time and intensive care unit (ICU) stay were also documented. Demographic data (gender, age, ejection fraction, and New York Heart Association [NYHA] classification) showed no difference. N group showed higher incidence of rhythm disturbance. Although intubation time showed no difference, ICU stay of N group was longer than V group. Revascularization of non-myocardium was associated with higher incidence of rhythm disturbance and longer ICU stay as compared with viable myocardium.