The Conventional Median Sternotomy Approach versus Minimally Invasive Surgical Treatment of Patients with Native Mitral Valve Infective Endocarditis

Objectives: Patients with infective endocarditis (IE) of the native mitral valve (MV) are often critically ill with a high rate of morbidity and mortality following surgery. In general, minimally invasive surgery on the mitral valve (MIMVS) is associated with reduced morbidity. However, little is known concerning clinical outcomes after MIMVS in patients with MV IE. The aim of this study was to compare clinical outcomes of patients receiving MIMVS treatment with the conventional full median sternotomy (MS) approach in patients presenting with IE of the native MV.

Methods: From 2009 to 2019, a total of 154 patients with acute (n = 131, 85%) or subacute (n = 23, 15%) IE of the native MV were operated at our institution and were included in the analysis. Patients with prosthetic MV IE, as well as concomitant surgical procedures including aortic valve surgery, septal myomectomy or CABG, were excluded. Patients not operable via MIMVS were also excluded. From the total amount of 154 patients, 42 received MIMVS treatment and 112 received surgery via MS. Both preoperative risk scores, STS PROM (5.32 [4.70] for the MIMVS group vs. 9.96 [10.61] for the MS group [p < 0.007]) and DeFeo (10.95 [7.70] for the MIMVS group vs. 16.67 [9.36] for the MS group [p < 0.001]), of the un-matched population were significantly different. For this reason, we performed nearest neighbor propensity score matching (PSM) to adjust for potential confounders and endocarditis severity. The dedicated DeFeo score is a mortality risk prediction score regarding cardiac surgery on patients presenting with native heart valve IE. Baseline matching characteristics were age, gender, BMI, preoperative NYHA ≥ 3, LVEF-grade (<30%, 30–50%, >50%), previous cardiac surgery, insulin dependent diabetes mellitus, hypertension, coronary artery disease, atrial fibrillation, dialysis, creatinine, STS PROM isolated MVR Model, DeFeo score, staphylococcus aureus, preoperative inotropes, concomitant procedure, and replacement or repair. PSM resulted in 39 pairs.

Result: Significant differences in clinical outcomes between the MIMVS and MS groups were found in ventilation time (708 vs. 1440 minutes; p = 0.002), RBC transfusion (1 vs. 4 units; p < 0.001), FFP transfusion (0 vs. 1 units; p = 0.001), reintubation after extubation (2 vs. 10; p = 0.012) and ICU stay (1 vs. 3 days; p = 0.032). There was no difference in mortality.

Conclusion: MIMVS for native MV IE provides clinical benefits in the postoperative intensive care setting when compared with the conventional full median sternotomy approach.

Publication History

Article published online:
19 February 2021