Clinical Analysis Of Active Infective Endocarditis Via Mitral Valve Repair

Background:Infective endocarditis (IE) is among the most severe infectious disease, the prevention of which has not decreased its incidence. Complications such as acute brain embolization,cerebral hemorrhage and infectious aneurysm in left-sided infective endocarditis have significant implications for clinical decision-making.This was a retrospective study of a clinical experience at a single institution,aiming to summarize the factors and outcomes of MVP in treating infective endocarditis.Methods:We investigated 40 native mitral valve operations during active-phase infective endocarditis. Between Feb 2011 and Feb 2015,40 consecutive patients (mean age,42.4±14.9 years; range,21-82years; 26 men) with active infective endocarditis underwent MV surgery.All patients were diagnosed with IE based on the modified Duke criteria.Blood cultures are positive in 55.0% of cases(22 patients).Causative microorganisms were isolated and identified in all blood culture positive patients. The microorganisms responsible for endocarditis were Streptococcus species in 15(37.5%) patients and Staphylococcus species in 1 (2.5%). The most suitable antimicrobial regimen, as suggested by the guidelines, was started.The time from initiation of medical treatment to operation was 11.4±12.2 days. All operations were performed through median sternotomy and performed with cardiopulmonary bypass(CPB) established with ascending aortic and bi-caval cannulation. The ascending aorta was cross-clamped and cardiac asystole achieved using intermittent antegrade and retrograde cardioplegia.Results:Mitral valve repair was performed in all the patients, using prosthetic annuloplasty in 34, an autologous pericardial patch in 13,artificial chordal replacement in 7,transfering of chordal in 1,and the size of mitral annuloplasty ring is 29.3±2.1mm. Hospital mortality was 2.5%(1/40), due to overwhelming infection and MODS(multiple organ dysfunction syndrome).1 patient died 2 months after MVP due to blood infection of Staphylococcus aureus and subsequent MODS.1 patient needed re-do of mitral valve replacement because of hematolysis after 15 days from MVP.The postoperative LVEDD(left ventricular end-diastolic dimension) was significantly smaller (56.8±6.7 vs. 49.7±5.7mm) and NYHA classification was significantly lower (2.25±1.07 vs. 1.06±0.25). Mitral regurgitation requiring re-operation occurred in 2 patients during follow-up,3months and 5months respectively.Conclusions:Mitral valve repair is feasible in active-phase infective endocarditis, and results in better LVEF and improved regression of left ventricular dimensions compared to preoperative left heart dimensions.