Y. Sanaiha1, A. Mantha1,2, Y. Seo1, L. Mukdad1, V. Dobaria1, Y. Juo1, R. Morchi2, P. Benharash1 1David Geffen School Of Medicine, University Of California At Los Angeles,Cardiac Surgery,Los Angeles, CA, USA 2University Of California – Irvine,Cardiothoracic Surgery,Orange, CA, USA
Introduction:
Background: Mitral valve replacement and repair have been debated as the optimal strategy to treat mitral regurgitation. While several studies have demonstrated the superiority of repair strategies from a clinical perspective, readmissions and resource utilization with each modality remains ill defined. Since readmission rates are considered indicators of quality, the present study aimed to evaluate the overall costs of care and rehospitalization rates of the respective strategies in a large representative national sample.
Methods:
Patients who underwent isolated mitral valve repair or replacement from Jan. through June in the 2010-2014 National Readmission Database (NRD) were analyzed. The NRD is an all-payer inpatient database maintained by the Healthcare Cost and Utilization Project (HCUP) that estimates more than 35 million annual U.S. hospitalizations. The primary outcomes were index mortality, length of stay, 30-day and 6-month readmission and GDP-adjusted costs. We utilized hierarchical linear models adjusting for demographics, cardiovascular risk factors, and Elixhauser Comorbidity Index.
Results:
Of the 54,858 patients enrolled, 29,845 (54%) received replacement and 25,013 (46%) repair. Patients undergoing replacement were more likely to be female (57 vs 40%, P<0.001), older (66 vs. 63 yr, P<0.001), have Medicare (56 vs 42%, p<0.001) and have lower Elixhauser score (5.0 vs. 4.0, P<0.001). Replacement was associated with higher adjusted in-hospital mortality (5.4% vs. 1.2%, OR= 2.6, P<0.001), higher adjusted costs ($64,158 vs. $43,643, β=0.16, P<0.001), longer hospitalization (14.4 days vs. 8.8 days, IRR:1.17, P<0.001). All-cause readmission at 30 days (19.6% vs 13.5%, OR=1.21, P<0.001) and cost of care 30-day readmission ($17,391 vs. $12,744, β=0.16, p<0.001) were significantly higher after replacement, most commonly due to 1) atrial fibrillation, 2) heart failure exacerbation, and 3) pleural effusion. Similarly replacement had higher adjusted odds of readmission at 6 months (34% vs. 22%, OR:1.26 P<0.001).
Conclusion:
In this study of U.S. patients who underwent isolated mitral valve surgery from 2011-2014, readmission rates remain high. After adjustment for demographics, comorbidities, and hospital level variation, replacement was associated with greater length of stay, mortality and 30-day readmission. Repair first approach may be beneficial during the index hospitalization and in follow up. Based on available literature and our findings, strategies to maximize repair warrant implementation at the national level and beyond centers of excellence.