Anti-Coagulation Management in Pediatric Ventricular Assist Device: A Quality Improvement Target

Impact of Weight on Ventricular Assist Device Outcomes in Dilated Cardiomyopathy Patients in Pediatric Centers: An ACTION Registry Study

Ventricular assist device (VAD) options vary for children in different weight groups. This study evaluates contemporary device usage and outcomes for children based on weight. Data from the Advanced Cardiac Therapies Improving Outcomes Network (ACTION) registry were examined for patients with dilated cardiomyopathy (DCM) in 4 weight cohorts: <8 kg, 8-20 kg, 21-40 kg, and >40 kg, for devices implanted 3/2013-10/2020. Adverse event rates and ultimate outcome (deceased, alive on device, transplanted, or ventricular recovery) were analyzed. 222 DCM patients were identified with 24% in cohort 1, 23% in cohort 2, 15% in cohort 3, and 38% in cohort 4. Of 272 total implants, paracorporeal pulsatile devices were most common (95%) in cohorts 1 and 2 and intracorporeal continuous devices (81%) in cohorts 3 and 4. Stroke was noted in 17%, 12%, 6%, and 4% of cohorts, respectively (Cohort 1 vs. 4 and 2 vs. 4 - p = 0.01; other comparisons - not significant). Incidences of major bleeding, device malfunction, and infection was not different. All cohorts had >90% positive outcomes. Stroke incidence was higher in smaller cohorts, but other outcomes were similar. Positive outcomes were attained in over 90% across all weight groups, demonstrating excellent outcomes using current VADs in this DCM population.

Time in Therapeutic Range for Bivalirudin Among Pediatric Ventricular Assist Device Recipients

Given the adverse event rates involving bleeding and thrombosis among children on ventricular assist devices (VADs), anticoagulant management has become a focal point for quality improvement and innovation. There may be advantages to using direct thrombin inhibitors, such as bivalirudin, though this has not been fully explored. As the percent time in therapeutic range (%TTR) for anticoagulants is classically associated with improved clinical outcomes, we evaluated the %TTR for bivalirudin among pediatric VAD recipients. Using a modification of the Rosendaal method, %TTR was calculated using activated partial thromboplastin time measurements for 11 VAD recipients in the early postoperative period (postoperative days 0-14) and for the duration of VAD support. In the initial 2 weeks after VAD implant, mean %TTR was 68.7 (±13.0). During the entire support course, the mean %TTR improved to 79.6 (±11.0). There was an era effect with improving %TTR in the latter half of the study period. We report very good %TTR for bivalirudin both in the first 2 weeks post implant and this improved over the duration of support. Because %TTR reflects the degree of safety and efficacy in chronic anticoagulation, this relatively high %TTR among a diverse, often critically ill cohort suggests that bivalirudin may be a promising agent. Although this study was underpowered to comprehensively evaluate adverse events on bivalirudin, this represents an important next step for larger scale study.