Trend, predictors, and outcomes of combined mitral valve replacement and coronary artery bypass graft in patients with concomitant mitral valve and coronary artery disease: a National Inpatient Sample database analysis

Aims: Combined mitral valve replacement (MVR) and coronary artery bypass graft (CABG) procedures have been the norm for patients with concomitant mitral valve disease (MVD) and coronary artery disease (CAD) with no large-scale data on their safety and efficacy.

Methods and results: The National Inpatient Sample database (2002-18) was queried to identify patients undergoing MVR and CABG. The major adverse cardiovascular events (MACE) and its components were compared using a propensity score-matched (PSM) analysis to calculate adjusted odds ratios (OR). A total of 6 145 694 patients (CABG only 3 971 045, MVR only 1 933 459, MVR + CABG 241 190) were included in crude analysis, while a matched cohort of 724 237 (CABG only 241 436, MVR only 241 611 vs. MVR + CABG 241 190) was selected in PSM analysis. The combined MVR + CABG procedure had significantly higher adjusted odds of MACE [OR 1.13, 95% confidence interval (CI) 1.11-1.14 and OR 1.96, 95% CI 1.93-1.99] and in-hospital mortality (OR 1.29, 95% CI 1.27-1.31 and OR 2.1, 95% CI 2.05-2.14) compared with CABG alone and MVR alone, respectively. Similarly, the risk of post-procedure bleeding, major bleeding, acute kidney injury, cardiogenic shock, sepsis, need for intra-aortic balloon pump, mean length of stay, and total charges per hospitalization were significantly higher for patients undergoing the combined procedure. These findings remained consistent on yearly trend analysis favouring the isolated CABG and MVR groups.

Conclusion: Combined procedure (MVR + CABG) in patients with MVD and CAD appears to be associated with worse in-hospital outcomes, increased mortality, and higher resource utilization compared with isolated CABG and MVR procedures. Randomized controlled trials are needed to determine the relative safety of these procedures in the full spectrum of baseline valvular and angiographic characteristics.