Real-world outcomes of surgery for native mitral valve endocarditis

Consensus guidelines recommend repair over replacement for the surgical treatment of active native mitral valve infective endocarditis. However, contemporary practice and long-term outcome data are limited.

Multivariable Cox regression was used to compare outcomes of 1970 patients undergoing isolated primary mitral valve repair (n = 367, 19%) or replacement (n = 1603, 81%) for active infective endocarditis between 1998 and 2010 in New York and California states. The primary outcome was long-term survival. Secondary outcomes were recurrent endocarditis and mitral reoperation. Median follow-up time was 6.6 years (range 0-12), and last follow-up date was December 31, 2015.

Mitral valve repair rates increased from 10.7% to 19.4% over the study period (P < .001). Patients undergoing mitral repair were younger (55 ± 15 vs 57 ± 15 years, P = .005), less likely to have congestive heart failure (46.3% vs 57.1%, P < .001), and less likely to have staphylococcal infections (21.3% vs 32.0%, P < .001). Twelve-year survival was 68.8% (95% confidence interval [CI], 62.5%-74.3%) after mitral repair, versus 53.5% (95% CI, 50.6%-56.4%) after replacement (adjusted hazard ratio, 0.71; 95% CI, 0.57-0.88; P = .002). Mitral repair was associated with lower rate of recurrent endocarditis at 12 years than replacement (4.7% [95% CI, 2.8%-7.2%] vs 9.5% [95% CI, 8.0-11.1%]; P = .03), and similar rate of reoperation (9.1% [95% CI, 6.2%-12.8%] vs 8.6% [95% CI, 7.1%-10.4%]; P = .12).

In active endocarditis, mitral valve repair is associated with better survival and lower risk of recurrent infection compared with valve replacement and should be the surgery of choice when feasible.