Preoperative predictors of low flow limit controller configuration following HeartMate 3 implantation

This study aimed to identify preoperative factors associated with postoperative replacement to a controller configured with a Low Flow Limit (LFL) of 2.0 L/min following HeartMate 3 (HM3) left ventricular assist device (LVAD) implantation, with the goal of establishing proactive selection criteria to improve patient safety and quality of life (QOL). This single-center, retrospective, observational study included 127 patients who underwent primary HM3 implantation between June 2019 and March 2025. Patients were divided into those who maintained the standard LFL of 2.5 L/min controller throughout follow-up (Standard group, n = 78) and those who required postoperative replacement with a controller configured with an LFL of 2.0 L/min (2.0-LFL group, n = 49). Preoperative clinical, laboratory, echocardiographic, and hemodynamic parameters were compared using univariate and multivariate logistic regression analyses, together with receiver operating characteristic (ROC) curve analysis. 2.0-LFL group had significantly lower anthropometric indices, including height, weight, body mass index, and body surface area (BSA), as well as a shorter duration of heart failure, compared with Standard group. Although multiple clinical, echocardiographic, and hemodynamic variables were evaluated, multivariate analysis identified BSA as the sole independent predictor of postoperative controller replacement (odds ratio: 0.03; 95% confidence interval: 0.00-0.60; p = 0.022). ROC curve analysis demonstrated that a preoperative BSA cutoff value of 1.43 m² yielded an area under the curve of 0.74, with a specificity of 89.7% and a sensitivity of 38.8%. Patient body size, particularly BSA, appears to be the primary determinant of the need for postoperative replacement to an LFL 2.0 L/min controller after HM3 implantation. Pre-emptive selection of a 2.0 L/min controller based on a BSA threshold of 1.43 m² may provide a practical strategy to reduce unnecessary postoperative controller replacements while maintaining patient safety and QOL in LVAD patients.