Impact of Renal Dysfunction on Periprocedural Outcomes in Patients with Ischemic Cardiomyopathy Undergoing Elective Coronary Artery Bypass Graft (CABG)

Abstract

Background Ischemic cardiomyopathy is associated with multiple comorbidities including diabetes, hypertension, hyperlipidemia, and kidney disease. Patients with end-stage renal disease (ESRD) and left ventricular systolic heart failure have a 2-year cumulative survival as low as 33%. Chronic kidney disease (CKD) dramatically increases the Society of Thoracic Surgeons (STS) risk score for CABG. Hypothesis Patients with preoperative CKD undergoing elective revascularization with CABG for ischemic cardiomyopathy will have worse periprocedural outcomes. Methods From the 2006-2014 National Inpatient Sample, we identified hospitalizations for systolic heart failure (ICD-9 codes 428.1, 428.X, 428.4X, or 428.9) undergoing CABG (ICD-9 procedure codes 36.1X). Those with acute myocardial infarction (code 410.X) were excluded. Patients were categorized into normal preoperative renal function, preoperative CKD stages 1-4 (diagnosis codes 585.1-4 or 585.9), and preoperative ESRD (diagnosis codes 585.5-6), and compared in terms of demographics, comorbidities, in-hospital mortality, length of stay (LOS), cost of care, and postoperative complications. Trends over time were assessed with the Cochran Armitage and Cuzick tests. Multivariate models were constructed with logistic and linear regression (gamma function) using NIS discharge weights and adjusted for age and comorbidities (hypertension, hyperlipidemia, diabetes mellitus, obesity, smoking, and family history of myocardial infarction). Results Over the study period, trends showed a decline in in-hospital mortality in normal preoperative renal function and CKD stages 1-4 (p Conclusions Patient with ESRD undergoing CABG for ischemic cardiomyopathy continue to have elevated in-hospital mortality despite an overall improvement in the non ESRD cohorts.