Study Design and Patient Characteristics
This study was approved by the University of Wisconsin-Madison Institutional Review Board. A retrospective review was performed of all patients who received LVAD implantation, with either HM3 LVAD or primarily with the HeartWare HVAD System, in the Cardiothoracic Surgery division at the University of Wisconsin between June 2018 to June 2020. Patients undergoing an operation for LVAD pump exchange were excluded from the study. Medical records were reviewed for patient demographics, cardiac surgery history, surgical approach to LVAD implantation (sternotomy vs. BT), past medical history, preoperative right heart catheterization, preoperative ejection fraction, INTERMACS profile, need for preoperative hemodynamic support, and postoperative hospital course.
The inflow cannula angle was measured by one reviewer (EMS) on the first chest radiograph available postoperatively using the angle measurement tool within the Change Healthcare Radiology SolutionsTM PACS system. The angle was recorded as the line above the horizontal plane, and the horizontal plane was measured from a line visually fitted to the vertebral bodies (Figure 1). The measurements were validated by a board-certified chest radiologist (ESK).