CENTRIFUGAL-FLOW LVAD INFLOW CANNULA POSITION: PREOPERATIVE INFLUENCES AND POSTOPERATIVE OUTCOMES

Background: We previously demonstrated better inflow cannula (IFC) position and reduced pump thrombosis with a centrifugal-flow LVAD (CF-LVAD) compared to an axial-flow device. We hypothesized that implant technique and patient anatomy would affect CF-LVAD IFC positioning and that malposition would impact LV unloading and outcomes. Methods: Pre- and postoperative computed tomography (CT) scans were reviewed for patients with six-month follow-up. Malposition was quantified using angular deviation from an ideal line in two planes. IFC position was compared between conventional sternotomy (CS) and lateral thoracotomy-hemisternotomy (LTHS). The influence of LV end-diastolic dimension (LVEDD), body mass index (BMI), and CT-derived anatomy was determined. LV unloading was assessed by LVAD flow index (FI) and pre- to post-LVAD decrement in mitral regurgitation (MR) and LVEDD. Outcome measures were pump thrombus or stroke (PT/eCVA); 30-day and total heart failure-related readmissions (HFRAs); and survival free of surgery for LVAD dysfunction. Results: One hundred fourteen patients met criteria. Total malposition magnitude was higher for CS than LTHS (p=0.04). Midline-LV apex distance predicted lateral-plane malposition (p=0.04), while apex-LVOT angle predicted both anterior- (p=0.01) and lateral-plane (p=0.04) malposition. Lateral-plane malposition predicted decreased LVAD FI at three (p=0.03) and six (p=0.01) months. Total malposition magnitude predicted increased 30-day HFRAs (p=0.04), while lateral-plane malposition predicted more overall HFRAs (p=0.01). Malposition was not associated with PT/eCVA, changes in MR or LVEDD, or survival free of surgical revision. Conclusions: Patient anatomy and surgical technique were associated with CF-LVAD IFC malposition. In turn, malposition was associated with increased readmissions and decreased LVAD FI.