Impact of Pulse Pressure on Hemocompatibility Related Adverse Events during Support with Continuous Flow Left Ventricular Assist Devices: An Analysis of the INTERMACS Registry

Abstract

While the impact of mean arterial pressure (MAP) on adverse events during left ventricular assist device (LVAD) support has been well established, there remains significant controversy regarding the impact of pulse pressure (PP) on clinical outcomes. We evaluated the impact of PP on post-implant hemocompatibility related adverse events (HRAE). Using the INTERMACS registry, we identified patients who received a primary, durable continuous-flow LVAD with distinct systolic and diastolic blood pressure readings at 3-months post-implant. Patients requiring mechanical right ventricular assist devices or inotropic support were excluded. Patients were then stratified into low, medium, and high pulsatility tertiles. Kaplan-Meier survival estimates and Cox Proportional Hazard Models were used to assess the impact of pulsatility on HRAEs. A total of 4745 patients were classified into low (n=1508), medium (n=1675), and high (n=1562) pulsatility groups. There was no correlation between PP and MAP in this population (Figure 1A) and no clinically significant difference in MAP between the groups. Significant pre-implant determinants of pulsatility included female sex, BMI, race, device type, and peripheral vascular disease. Patients with lower pulsatility had more RV dysfunction and higher pro-BNP levels as compared to those with higher pulsatility. PP was a significant risk factor for stroke (HR: 1.09, CI: 1.04 - 1.15, p=0.001 per 10mmHg increase) independent of MAP. Patients with high MAP and high PP had the highest stroke risk (Figure 1B). PP was not associated with GI bleeding, device thrombosis. thromboembolic events, or post-implant survival. High PP is associated with increased risk of stroke during LVAD support. Pulsatility may represent an additional therapeutic target in this patient population.