Improved survival and decreasing incidence of adverse events with the HeartMate II left ventricular assist device as bridge-to-transplant therapy

Abstract

Background: Pulsatile left ventricular assist devices (LVADs) are effective as bridge-to-transplant therapy, but they are limited by their large size and lack of durability. Smaller, more durable, continuous flow devices such as the HeartMate II LVAD are increasingly being used. The aim of this study is to report our single-center experience with this device as bridge-to-transplant therapy.

Methods: Overall, 47 patients received HeartMate II LVADs at our center from June 2005 to July 2007; 32 as bridge to transplant, 7 as destination therapy, and 8 as exchange therapy for a failed HeartMate XVE. We reviewed our experience with the device as bridge-to-transplant therapy and report on patient survival and adverse events.

Results: The mean age of the bridge-to-transplant patients was 50.75 +/- 13.78 years; 10 (31.3%) were female. The cause of the underlying disease was ischemic in 18 patients (56.3%), idiopathic in 11 (34.4%), myocarditis in 1 (3.1%), postpartum cardiomyopathy in 1 (3.1%), and congenital heart disease in 1 (3.1%). The mean duration of HeartMate II support was 193.2 +/- 139.9 days. At 30 days after HeartMate II placement, the patient survival was 96.9% by Kaplan-Meier analysis; at 6 months (alive or transplanted), 86.9%. Major adverse events included bleeding requiring reexploration in 5 patients (15.6%), right ventricular failure requiring right ventricular assist device support in 2 (6.3%), LVAD-related infections in 4 (12.5%), neurologic or thromboembolic events in 2 (6.3%), and gastrointestinal bleeding in 5 (15.6%). We noted one serious device malfunction (3.1%) resulting in the patient's death; in addition, 2 patients experienced pump thrombosis (6.3%).

Conclusions: Despite morbidity, use of the HeartMate II LVAD as bridge-to-transplant therapy is associated with excellent survival and low mortality rates. We found a marked decrease in morbidity related to right ventricular failure, to device-related infections, and to thromboembolic events. However, the requirements for anticoagulation therapy may be associated with increased mediastinal and gastrointestinal bleeding. Strategies to optimize anticoagulation therapy may further improve results for these critically ill patients.