Abstract 18168: External Validation of Right Heart Failure Risk Scores Following Left Ventricular Assist Device Implantation and Evaluation of the Role of Emerging Echocardiographic Indices

Introduction: Preoperative risk scores for right heart failure (RHF) following left ventricular assist device (LVAD) implantation show a discrimination in outcome prediction in derivation cohorts but have not undergone extensive external validation. The aims of the study were to externally validate previously described RHF risk scores and to determine to which extent novel echocardiographic indices can improve risk stratification. Methods: We evaluated five clinical RHF risk scores (Michigan, Kormos et al, Penn, CRITT, and Utah) in 158 patients (age 56.0±12.6; 78.5% men; 36.7% destination therapy) having undergone continuous-flow LVAD implantation between February 2009 and August 2015. Clinical, laboratory, hemodynamic, and echocardiographic data were compared between patients with and without RHF, and risk factors identified. Measures of right heart function included right ventricular free wall longitudinal strain (RVLS), right atrial end-systolic area index (RAAI), and right ventricular fractional area change (RVFAC). Results: RHF occurred in 36.7% of patients. Three of the 5 scores were different from the null hypothesis, yet the discriminative performance was modest (CRITT score C=0.66 [0.58-0.74], Michigan score C=0.61 [0.53-0.69], Kormos score C=0.60 [0.51-0.67]). Our multivariate analysis identified INTERMACS profile (OR 2.29 [1.38-3.79, p=0.001]) and bilirubin greater than 1.7mg/dL (OR 2.39 [1.03-5.56], p=0.043), RAAI (OR 2.75 [1.32-5.75], p=0.007) and RVGLS (OR 2.20 [1.01-4.82], p=0.048) as independently associated with RHF. The C-statistic for this model was 0.77 [0.69-0.83]. Conclusions: Predictive risk scores for post-LVAD RHF perform modestly in external validation cohorts. Novel echocardiographic right heart parameters, such as RA size and RVLS, moderately improve the performance of clinical scores.