Cluster analysis of preoperative echocardiographic findings and outcomes following left ventricular device implantation

Objective: To investigate whether preoperative echocardiography findings determine postoperative continuous-flow left ventricular assist device outcomes. Methods: From January 2003 to June 2017, 490 patients received a durable, continuous-flow left ventricular assist device. Two-step clustering of parameters including heart rate and preoperative echocardiographic findings (ie, left ventricular [LV] ejection fraction, right ventricular [RV] function, aortic insufficiency, mitral regurgitation [MR], tricuspid regurgitation [TR]) was performed and identified 5 distinct clusters associated with LV failure: group 1: moderate right ventricular dysfunction (RVD), severe MR and mild TR (n = 110); group 2: severe RVD, severe MR and TR (n = 64); group 3: moderate RVD and severe aortic insufficiency (n = 16); group 4: mild RVD and mild valvular pathology (n = 163); and group 5: moderate-severe RVD and mild valvular pathology (n = 137). Silhouette measure of cohesion and separation demonstrated satisfactory separation at 0.6. Results: Group 2 had the greatest Interagency Registry for Mechanically Assisted Circulatory Support Level 1 (25%, P =.010), preoperative right atrial pressure (11 +/- 5 mm Hg, P<. 001), incidence of postoperative right ventricular failure (RVF; 20%, P =.001), delayed closure of the sternum (61%, P =.002), postoperative permanent dialysis (6%, P =.04), rate of tricuspid valve repair (n = 52; 81%, P<. 001), and lowest RV stroke work index (489 +/- 228 cc mm Hg/m(2)/beat, P<. 001). RVF in groups 1, 3, 4, and 5 was 6%, 0%, 4%, and 9%, respectively. No differences in incidence of heart transplantation (P =.400) or survival (P =.535) were found. Severe TR predicted RVF in those with moderatesevere preoperative RVD (P =.001, odds ratio 3.9). Conclusions: Clustering demonstrated the importance of preoperative TR in predicting RVF. Combined severe LV and RV failure with severe MR and TR portends the worse prognosis.