Preoperative passive venous pressure-driven cardiac function determines left ventricular assist device outcomes

Area of Science:

• Cardiology
• Medical Devices
• Heart Failure Research

Background:

• Right heart output in heart failure can be compensated by increasing systemic venous pressure.
• The ability of passive cardiac output to predict outcomes after left ventricular assist device (LVAD) implantation was investigated.

Purpose of the Study:

• To determine if the magnitude of passive cardiac output can predict outcomes in patients receiving a continuous-flow LVAD.
• To identify a threshold for passive cardiac index (PasCI) that predicts LVAD death within two years.

Main Methods:

• Retrospective review of 383 patients who received a continuous-flow LVAD.
• Calculation of pre-LVAD passive cardiac index (PasCI) using right atrial pressure, mean pulmonary artery pressure, total cardiac output, and body surface area.
• Application of the Youden J statistic to identify the PasCI threshold predictive of LVAD death.

Main Results:

• Increased preoperative PasCI was associated with reduced survival (HR, 2.27; P < .01) and increased risk of right ventricular failure (RVF) (HR, 3.46; P = .04).
• A preoperative PasCI ≥0.5 predicted LVAD death and was associated with poorer survival (P = .02).
• Patients with PasCI ≥0.5 showed trends toward more heart failure readmission days and increased gastrointestinal bleeding, and were more likely to have multiple heart failure readmissions.

Conclusions:

• Augmenting right heart output via increased venous pressure negatively impacts end-organ function and increases heart failure readmission days.
• A pre-LVAD PasCI ≥0.5 is linked to worse post-LVAD survival and increased RVF.
• The PasCI metric may improve management of LVAD candidates with RV dysfunction when used alone or in predictive models.