Factors Influencing Survival Outcomes in Patients with Left Ventricular Dysfunction after Coronary Revascularization

Abstract

Abstract Background Outcomes in patients with left ventricular (LV) dysfunction after coronary revascularization are influenced by multiple factors; however, it is difficult to compare a direct relationship between LV dysfunction and mortality due to the presence of confounding variables, so we attempted to observe the influence of risk factors on outcomes in severe LV dysfunction patients after revascularization and delineate if any of them have an effect on one-year mortality of such patients. Methodology This is a single center prospective study, where the studied population were severe LV dysfunction patients who underwent percutaneous transluminal coronary angioplasty (PTCA) and followed-up for one year and at the end of one year, impact of gender, age, type 2 diabetes mellitus (DM), hypertension (HTN), obesity, chronic kidney disease (CKD), cerebrovascular accident (CVA), hypothyroidism, smoking and alcohol on one-year mortality and MACE (major adverse cardiovascular events), which included reinfarction (nonfatal), recurrence of angina, repeat percutaneous intervention (PCI) or coronary artery bypass grafting (CABG) and heart failure. The above factors were analyzed and statistically approached to observe the impact of those risk factors on one-year mortality and determine whether the timing and mode of revascularization, and number of coronary arteries involved, had any influence on mortality or MACE events. By comparing different parameters of the study with respect to mortality, a regression analysis was made at the end of one year Results As many as 152 patients of severe LV dysfunction (ejection fraction < 30%) were enrolled in the study, among which 115 (75.6%) patients were males, and 37 patients were females (24.3%), with a mean age of 57.6 years; 89 (58.5%) patients were hypertensive, 80 (52.6%) patients were diabetics, 42 (27.6%) patients were smokers, 20 (13.1%) patients were alcoholics, 9 (5.9%) had CKD, one (0.6%) patient had hypothyroidism and one (0.6%) patient had a history of CVA; 46 (30.2%) patients presented with acute coronary syndrome (ACS) and 106 (69.7) patients had chronic stable angina (CSA); 144 (94.7%) patients underwent PTCA (percutaneous transluminal coronary angioplasty), while eight (5.2%) patients underwent CABG. At the end of one year, mortality was six patients (3.94%). At the end of one year, regression analysis was done for all the confounding variables by observing their influence on the MACE or mortality; none of them showed statistically significant influence (p > 0.05). Conclusion At the end of one year, after revascularization in patients with severe LV dysfunction, no significant relationship could be ascertained between the mortality or MACE events and gender, age, DM, HTN, CKD, and alcohol or smoking. MACE or mortality may be attributed directly to LV dysfunction itself, and the observed mortality was higher than that of normal LV Function. Hence, in our study, LV dysfunction is the cause of mortality in the study population but not the other confounding variables.