Prosthesis-patient Mismatch After Mitral Valve Replacement-a Single-centered Retrospective Analysis

ObjectivesProsthesis-patient mismatch(PPM)may affect the clinical outcomes of patients undergoing mitral valve replacement(MVR)surgery.We aimed to investigate the incidence of PPM of the mitral position in our center and analyze the possible predictors of PPM as well as its effect on short-term outcomes.Based on our study,we hope to provide experiences for the prevention and management of prosthesis-patient mismatch after mitral valve replacement.Methods and materialsWe retrospectively examined all consecutive patients with isolated or concomitant mitral valve replacement at our center between 2013 and 2015.After inclusion and exclusion,a total of 1067 patients were analyzed.PPM was defined as an indexed effective orifice area(iEOA)of ? 1.2cm~2/m~2,calculated from the body surface area(BSA)of the patient and the effective orifice area(EOA)of the prosthesis.Altogether,189 patients reach the PPM criteria,whereas 878 patients formed the non-PPM control group.The baseline,echocardiographic,operative,and outcome data of all patients were collected and compared between the two groups.Multivariate logistic regression analysis was conducted to determine the preoperative predictors of PPM as well as the effect of PPM on early mortality.ResultsA total of 1067 patients were included in the study.PPM was detected in 15.9%of the patients while twelve patients(1.12%)met the criteria for severe PPM.Patients with PPM had higher age(63 vs 54,P<0.001),larger body surface area(1.64 ± 0.17m~2 vs 1.55 ± 0.16m~2,P<0.001)and were more like to be male(35.5%vs 47.1%,P<0.001)and1 obese(BMI 23.34 ± 2.86 kg/m~2 vs 22.07 ± 3.79 kg/m~2,P<0.001).Also,PPM patients had a higher prevalence of hypertension(24.9%vs 16.5%,P=0.009),coronary heart disease(4.8%vs 1.5%,P=0.009),smoking history(16.9%vs 10.4%,P=0.016).However,among patients replaced with bioprosthesis,there was a higher proportion of pre-operative mitral stenosis in PPM group than non-PPM group(58.3%vs 41.7%,P=0.019).There were no significant difference regarding atrial fibrillation,heart function,left ventricular ejection fraction,left atrial dimension,left ventricular end diastolic dimension,emergency operation and other co-existing disease.As for intra-operation data,PPM patients had a higher prevalence of bioprosthesis(50.8%vs 11.7%,P<0.001),combined CABG(5.8%vs 1.9%,P=0.005)and combined atrial fibrillation surgery(15.9%vs 8.7%,P=0.005).Logistic regression analysis showed that higher age(P=0.011),larger BSA(P<0.001),bioprosthesis(P<0.001)and smaller left ventricle end-diastolic dimension(LVDd,P<0.001)were predictors of PPM.There were no significant difference between PPM and non-PPM group regarding post-operational complications.Nine patients(0.84%)died during or after surgery,however logistic regression analysis showed that PPM was not a risk factor of short-term mortality(P=0.654).There were no significant difference regarding short-/mid-term heart function between PPM and non PPM groups(P=0.902).ConclusionsOur results demonstrated that higher age,bioprosthesis,larger BSA and smaller left ventricle were associated with mitral PPM.However,PPM was not associated with poorer early outcomes after mitral valve replacement surgery.In eastern part of China,the prevalence of mitral valve stenosis was high,whether the standard PPM criteria is suitable for patients of this district needs to be further verified.