Abstract
Purpose: Stress-gated myocardial perfusion scintigraphy (MPS) is used for prognosis in stable coronary artery disease (CAD). We sought to assess coronary artery bypass grafting (CABG) outcomes in stable coronary artery disease patients who had myocardial perfusion scintigraphy and left ventricular (LV) dysfunction. Methods: Stable CAD patients who underwent CABG (2012-2019) and had stress-gated MPS were identified retrospectively. Based on the post-stress LV ejection fraction, a total of 130 patients were divided into a control group (51%) and LV dysfunction group (49%). Results: Patients with left ventricular dysfunction had significantly more mean summed stress score (22.1 ± 9 Vs. 12.5 ± 8; P ≤ 0.001) and summed resting score (14.6 ± 8 Vs. 3.7 ± 4; P ≤ 0.001) compared to the control group respectively. They also had a greater risk for developing low cardiac output syndrome after surgery (OR: 2.9, 95% CI 1.1-6.6, P=0.033). At 4.7 years, freedom from cardiac death was not statistically significant between the left ventricular dysfunction and control groups, respectively (90.2% vs. 95.6%; P=0.157). Cardiac death was not influenced by either ventricular dysfunction at the time of surgery (HR: 2.6, 95% CI 0.64-10.6, P=0.182) nor by having percent ischemic myocardium > 10% (HR: 0.86, 95% CI 0.23-3.24, P=0.826). Conclusion: Significant myocardial ischemia and ventricular dysfunction before complete surgical revascularization did not influence the risk of cardiac-related deaths on long-term follow-up. This might be related to the improved survival after CABG in patients with myocardial ischemia and left ventricular dysfunction.