Thoratec implantable ventricular assist device: The Papworth experience

Objective

The Thoratec (Thoratec Corp, Pleasanton, Calif) implantable ventricular assist device (IVAD) can be used for univentricular or biventricular support. The objective of this study is to review the 5-year experience of bridging patients to heart transplantation with this device in a single center. Surgical aspects, including hybrid pump pocket, double tunneling of driveline, and optimal cannulae placement, are discussed.

Methods

This is a retrospective review of 24 patients treated between January 2002 and December 2007. Nineteen patients (79.1%) received a single implantable ventricular assist device as left ventricular assist devices, and 5 patients (21.9%) received 2 implantable ventricular assist devices as biventricular assist devices. The devices were implanted in pre-peritoneal/posterior rectus hybrid pump pockets. The driveline was passed through a 2-stage double-tunnel to exit onto the lateral chest wall. Patients were anticoagulated with Warfarin aiming for an international normalized ratio of 2.0 to 3.0.

Results

Twenty male and 4 female patients with a mean age of 39.8 years (17–57 years) and a body surface area of 1.87 m² (1.63–2.2 m²) were supported for a total of 2308 patient-days. Mean duration of support was 96 days (10–301 days). The cause of heart failure was dilated cardiomyopathy in 18 patients and ischemic cardiomyopathy in 6 patients. Preoperatively, 23 patients were receiving inotropes, 12 patients required intra-aortic balloon pump support, 5 patients were intubated and mechanically ventilated, and 3 patients required continuous venovenous hemofiltration for renal support. Eleven patients (45.8%) were discharged with ventricular assist device support (1015 home patient-days). Complications observed were a) neurologic: stroke in 3 patients, transient ischemic attacks in 4 patients; and b) infection: driveline infection in 3 patients and pump pocket infection in 1 patient. There was no mechanical device failure. Support to transplantation was achieved in 17 patients (70.8%): 3 of 5 biventricular assist devices (60%) and 14 of 19 left ventricular assist devices (73.7%).

Conclusion

The Thoratec IVAD is a versatile and reliable ventricular assist device. It can provide univentricular or biventricular support for bridging patients to heart transplantation with acceptable complication rates. The portable Thoratec TLC-II console facilitated discharge while patients waited for a suitable donor heart.

CTSNet classification: 27, 34

Abbreviations and Acronyms: BVAD, biventricular assist device, CPB, cardiopulmonary bypass, CVVH, continuous venovenous hemofiltration, IVAD, implantable ventricular assist device, LV, left ventricular, LVAD, left ventricular assist device, PVAD, paracorporeal ventricular assist device, RV, right ventricular, RVAD, right ventricular assist device, VAD, ventricular assist device