Perioperative Strokes and Early Outcomes in Mitral Valve Surgery: A Nationwide Analysis

Abstract

Objective: To demonstrate the role of perioperative stroke as an independent risk factor for in-hospital morbidity and mortality after mitral valve surgery and review the trends in the early outcomes of mitral valve surgery over the past decade.

Design: Using data from the National Inpatient Sample database for analysis, all patients who underwent isolated mitral valve procedures were identified using International Classification of Diseases-Ninth Revision codes. Univariate and multivariate analyses of risk factors of in-hospital mortality and morbidity were performed.

Setting: Multi-institutional.

Participants: The study comprised patients who underwent mitral valve procedures from 1999 to 2011.

Interventions: Mitral valve repair or replacement.

Measurements and main results: Data on 21,821 patients showed an in-hospital mortality of 5.5% and morbidity of 63.30% (p<0.05). Perioperative strokes were experienced by 3.89% of the cohort after isolated mitral valve surgery (p<0.05). Independent predictors of adverse outcomes were age, female sex, emergency surgery, arrhythmias, hypertension, renal failure, coagulopathy, neurologic disorders, weight loss, anemia, postoperative cardiac arrest, and myocardial infarction. Perioperative strokes were found to be the strongest risk factor for postoperative mortality (odds ratio 2.34, 95% confidence interval 1.83-2.98) and morbidity (odds ratio 4.53, 95% confidence interval 3.34-6.15).

Conclusion: Age, female sex, emergency surgery, arrhythmias, hypertension, renal failure, coagulopathy, neurologic disorders, weight loss, fluid and electrolyte imbalance, anemia, postoperative cardiac arrest, and myocardial infarction were found to be significant predictors of morbidity and mortality after mitral valve surgery, with perioperative strokes posing the strongest risk. The trends in the last 10 years indicated a decrease in mortality and an increase in morbidity. Preoperative risk stratification and intraoperative identification for impending strokes appear warranted.

Keywords: in-hospital mortality; mitral valve surgery; morbidity; perioperative stroke.