Evaluation of Thoracotomy versus Median Sternotomy Approach in Third-Generation Left Ventricular Assist Device Implantation

Purpose The purpose of this study is to compare short term results of patients undergoing a third generation (HVAD™or HeartMate™ 3) Left Ventricular Assist Device (LVAD) implantation through either minimally-invasive, thoracotomy approach or standard median sternotomy. Methods We prospectively collected data on all patients at our institution that received an LVAD from September 2008 to February 2020. Surgical approach was decided by the implanting surgeon. We used 1:1 propensity score (PS) matching to compare the sternotomy versus thoracotomy groups. A logistic regression model based on 19 explanatory variables was used to estimate the propensity score. Overall survival post-implantation was summarized using Kaplan-Meier curves and compared using the log-rank test. Results A total of 272 patients were included, of whom 194 had sternotomy and 78 had either left thoracotomy and hemi-sternotomy or bilateral thoracotomies. Using PS matching, 128 (64/64) patients were selected. Demographics and operative characteristics were well balanced between groups. Overall, there was a trend towards better survival in thoracotomy group (33.1% vs 66.4%, p=0.06) at 5 years, but higher stroke rate (11% in sternotomy group vs 21% in thoracotomy group, p = 0.035). Following PS-matching, however, there was no difference in early or late mortality (Graph 1) but there was a higher rate of pump exchange in the thoracotomy group (2% vs 9%, p = 0.052). There was no difference in perioperative stroke rates (sternotomy 6% vs thoracotomy 9%), extubation time (2.5 days vs 2.5 days), right ventricular failure (13% vs 14%), renal failure (8% vs 5%) or hospital readmissions (81% vs 88%). Conclusion Minimally invasive LVAD implantation is feasible and safe in the current LVAD era. In a PS matched analysis, patients in the minimally invasive group displayed lower overall mortality, but without reaching statistical significance. Adverse events were similar in both groups.