Jarvik 2000 an Effective Bridge to Transplant in Preliminary Study

The Jarvik 2000 Heart provides satisfactory cardiac support and improves quality of life in heart failure patients who are waiting for a transplant, according to study results presented Monday at the Ninth Congress of the International Society for Rotary Blood Pumps.

Developed by Jarvik Heart, Inc. and the Texas Heart Institute in Houston, the Jarvik 2000 is a valveless, electrically powered miniature axial flow pump designed for long-term circulatory support that is placed directly into the left ventricle. Unlike other devices, which are implanted by way of a conventional chest wall opening through the sternum, the Jarvik 2000 is implanted via a left thoracotomy incision.

“The control unit is a simple analogue controller that is connected to a lithium ion battery,” said Dr. Timothy J. Myers, who is from the Texas Heart Institute. “It will run the system for 24 hours.”

Dr. Myers and others conducted a single-center, non-randomized feasibility study of ten patients, all of whom were in class lV heart failure awaiting transplantation. The average time on the pump was 73 days, ranging from 13 to 214 days. Seven patients eventually received donor hearts and did well during followup of up to a year and a half. Three patients died while awaiting transplant.

“In the immediate post-op period, up to 48 hours from baseline, we had a significant change in cardiac index, which is of course what we would expect,” Dr. Myers told the conference attendees. “The wedge pressure decreased by a significant amount and there was not a lot of change in arterial blood pressure, but what was significant about this was that inotropic support was reduced or eliminated in most patients.”

At baseline the mean cardiac index was 1.77 L/min/m² and the mean pulmonary capillary wedge pressure was 21.7 mm Hg. At 48 hours after implantation, the numbers had changed significantly. The mean cardiac index was 3.45 L/min/m² and the mean pulmonary capillary wedge pressure was 10.3 mm Hg.

“Pulmonary vascular resistance did not change very much, but the systemic vascular resistance was significantly reduced,” said Dr. Myers, “and this is likely the result of little or no inotropic support at 48 hours after the implant.”

Dr. Myers said that most of the patients reported an improvement in both their physical status and quality of life. The system is also easy to set up and operate, he noted, and technical problems have been minimal. “Overall, at this point, we can say that we can safely support patients for the maximum duration we’ve had, which is 7 months,” he concluded.