Ventricular Assist Device Implantation in the Pediatric Population: Does Pump Size Selection and Associated Hemodynamics Impact Outcomes?

Abstract

The use of pediatric ventricular assist devices (VADs) continues to evolve with the availability of smaller blood pumps. We examine the correlation of implanting appropriate sized blood pumps with a lower incidence of VAD related complications (VADRC). A 7-year retrospective review was undertaken for all pediatric VAD patients. Optimal VAD hemodynamics were defined as cardiac index of 2.7 L/m2 and rate of 80 beats per minute (bpm) with complete fill/empty of the blood pump. Patient/blood pump size match, VAD rate and fill/empty ratios were calculated (optimum = 1.0) and then correlated with incidence of VADRC. The study included 22 patients, mean age 9.77 years (6 mo-18 yrs) and mean body surface area (BSA) of 1.14 m2 (0.14 m2-2.32 m2), who underwent VAD implantation. VADRC included death while on support (n = 5), bleeding requiring reoperation (n = 8), hemolysis (n = 2), neurologic events (n = 2), thrombus formation (n = 3), and infection (n = 3). Six patients were bridged to transplant without any VADRC. This subset of patients had a mean blood pump size match ratio of 0.98, VAD rate ratio of 0.92 and fill/empty ratio of 1.00. Patients with VADRC (n = 16) were found to have a mean blood pump size match ratio of 0.72, VAD rate ratio of 0.72 and fill/empty ratio of 0.78. We report a series of pediatric patients with wide ranging BSA receiving VAD implantation. Selection of appropriate sized blood pumps can be correlated with decreased VADRC.

New 15-mL ventricular assist device in children with restrictive physiology of the left ventricle

“…The consequences of such physiologic anomalies are unclear; however, mismatch between chamber volume and body size may contribute to VAD-related complications. 4 We describe the successful use of a new 15-mL EXCOR pump in 2 children whose requirements fell between the ideal fill and flow characteristics of the existing pumps. In children with a body surface area ranging from 0.33 to 0.55m 2 and weight ranging from 7 to 12 kg, the 15-mL chamber complements the EXCOR infant range.…”

“…3 The risk of VAD-related complications may also be higher when the chamber volume is not appropriately matched to the patient size. 4 Restrictive left ventricular (LV) physiology presents a unique challenge for left VAD (LVAD) implantation in children because of potential problems with drainage with conventional LV apical cannulation. We describe the use of a novel 15-mL volume Berlin Heart Pediatric EXCOR VAD in 2 children with restrictive LV.…”