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

Abstract

Purpose Pediatric Ventricular Assist Device (VAD) therapy is associated with high rates of stroke and bleeding. There have been limited efforts to date, to define and implement optimal anticoagulation (AC) strategies in this population. ACTION (Advanced Cardiac Therapies Improving Outcomes Network) is the first pediatric VAD quality improvement network, with an initial goal of stroke reduction. This report describes baseline AC data from ACTION centers, including agents used and aggregate levels of performance, to inform development of specific interventions. Methods The AC practices of ACTION centers were assessed. Data collected included VAD type, weekly data characterizing AC agents used; time to achieve desired levels; and percentage of levels within the desired range. Results Data were collected from 11 centers, with a total of 30 patients. AC data were collected from 6/1-9/1/18, while strokes were collected retrospectively for the entire VAD support interval. Devices included: HVAD (12); EXCOR (10); Heartmate 3 (3); and 5 paracorporeal continuous flow devices. There were 5 strokes (16.7%). Intravenous AC included unfractionated heparin (36%), and bivalirudin (64%). There was wide variability between patients in the time to achieve first therapeutic AC level (Figure 1), with 15 patients at goal within 20 hours, while others required up to 170 hours. Heparin levels varied widely, with the percent of labs within range falling below 50%, in 50% of the weeks reported. For bivalirudin, levels were less variable, with percent of labs within range falling below 50% in only 14% of weeks reported. Conclusion At baseline, stroke rates remain high in the ACTION centers. Intravenous AC includes both heparin and bivalirudin, with high variability in time until therapeutic levels are achieved, and with high variability in subsequent levels, particularly for heparin. These data will inform interventions designed to reduce variability in AC performance as a basis for stroke reduction.