Sternal-Sparing Approach for LVAD Implantation Allows for a More Consistent Inflow Cannula Angle

PURPOSE Prior study has suggested an association between angulation of the inflow cannula and outcomes following left ventricular assist device (LVAD) implantation. A potential benefit of the sternal-sparing LVAD implantation technique is superior visualization of the apex in its natural anatomic position. Our hypothesis was the sternal-sparing technique would result in more consistent angle of LVAD implantation. METHODS This single-center, retrospective review included consecutive patients implanted from September 2015 through September 2019. Patients were stratified via surgical technique: sternal-sparing or median sternotomy. The coronal angle of the inflow cannula relative to the horizontal line was measured on the first available postoperative anterior-posterior chest radiograph (Figure 1). All measurements were calculated by trained radiologists. A randomly selected subgroup of patients was repeated by multiple readers to assess interrater reliability. RESULTS Of the 161 patients included in the study, 102 (63%) were implanted via the sternal-sparing approach. Preoperative patient characteristics were similar between cohorts. The inflow cannula angle was significantly different between cohorts (Figure 1, p=0.020). The sternal-sparing cohort had a more consistent angle (median [IQR], 18 [6-29] degrees) compared to the sternotomy patients (25 [10-42] degrees, p=0.020). Significantly more sternal-sparing patients had an angle ≤65 degrees (100% vs 93%, p=0.017), which has previously been associated with improved patient outcomes with a different model pump. CONCLUSION Our data suggests the angle of the inflow cannula after LVAD implantation is more consistently reproduced when utilizing the sternal-sparing approach compared to median sternotomy. Further research is needed to examine the relationship between inflow cannula angle and patient outcomes to determine the ideal inflow cannula angle for the fully magnetically levitated pump.