Background: Low cardiac output syndrome (LCOS) after surgical aortic valve replacement (SAVR) leads to increased mortality and health care related costs. Right ventricular free wall longitudinal strain (RVFWS) may be a risk factor in patients without severely reduced left ventricular ejection fraction (LVEF). All had LVEF >35%.
Purpose: To evaluate the role of RVFWS to predict the occurrence LCOS after surgical aortic valve replacement in patients without severely reduced LVEF.
Methods: We prospectively recruited patients with severe aortic stenosis, with class I indication for SAVR. Clinical, hemodynamic and echocardiographic data was collected. Conventional right ventricular function parameters and RVFWS were measured using speckle tracking echocardiography. Univariate and multivariate linear regression analysis was used to analyze variables related with the occurrence of LCOS.
Results: Eighty-one patients (63 years ±8 were included and LCOS occurred in 19 (23%). Patients with LCOS had more frequently diabetes (35.5 vs 10.5%, p=0.037), underwent more mitral valve replacement (3% vs 16%, p=0.046), had longer aortic clamping time (72 (85–116 min) vs 96 (79–136 min), p<0.0008), cardiopulmonary bypass time (99 (85–116 min) vs 120 (102–184 min) p<0.001), lower LV global longitudinal strain (GLS) (-17±4% vs 14±5%, p=0.001) and RVFWS (-14±4 vs -18±4%, p=0.0001). Interestingly LVEF (p=0.065), tricuspid annular plane systolic motion (p=0.28) right ventricular fractional area change (p=0.57) and right ventricular systolic pressure (p=0.062) did not differ. In the multivariate analysis, RVFWS was the only independent predictor of LCOS (Table). On ROC curve analysis a RVFWS with an absolute value lower than 15.1% had a sensitivity of 72% and a specificity of 79% (AUC=0.78) for LCOS occurrence.
Conclusions: RVFWS is a strong independent predictor of LCOS after aortic valve replacement in patients without severely reduced LVEF. RVFWS can improve risk stratification for LCOS in this patient subset. Future studies to confirm our findings are needed.