End-stage heart failure (HF) patients can be treated safely and effectively by the HeartWare Ventricular Assist System and see an improved quality of life and neurocognitive function, according to a study published in the March 22 issue of the Journal of the American College of Cardiology.
“Heart failure is a worldwide epidemic that contributes considerably to the overall cost of healthcare in developed nations,” the authors wrote. And while heart transplantation may be an effective treatment, it is restricted by the number of available donors; therefore mechanical circulatory support with left ventricular assist devices (LVAD) can be a more viable bridge-to-heart transplant or destination therapy for these patients.
In the current study, Martin Strueber, MD, of the Hanover Medical School in Hannover, Germany, and colleagues evaluated the safety and efficacy of the HeartWare Ventricular Assist System (HeartWare) as a means of support for patients with end-stage HF.
The study enrolled 50 end-stage HF patients between March 2006 and December 2008 and the primary endpoint was survival to transplant, cardiac recovery with device explants or continuous device support at 180 days. Of the 50 patients, 86 percent were men and the mean patient age was 48.5 years.
Strueber et al reported that the survival to heart transplantation, myocardial recovery and HVAD pump explants or ongoing support at six, 12 and 24 months after implant was 90 percent, 84 percent and 79 percent, respectively.
Twenty of the 50 patients had an estimated mortality that was above 50 percent at one-year and the median duration on HVAD pump support during the trial was 322 days—a range of 12 days to 847 days. Mean duration of HVAD pump support time was 348 days and cumulative support time was 47.8 years. No mechanical failures occurred with the HVAD system.
As of May 1, 2010, 40 percent of patients underwent heart transplant, 8 percent recovered myocardial function and had the device explanted and support was ongoing in 32 percent of patients. Median time to heart transplant was 267 days and nine patients died during support at a median duration of 94 days. Three patients died of sepsis, three of multiple organ failure and three of hemorrhagic stroke.
While 47 patients were discharged from the hospital, there were 53 readmissions for varying medical reasons. The researchers reported 92 adverse events for 39 patients—eleven of the 50 patients did not experience any adverse event during the follow-up period. The most common adverse events were due to infection.
“Over the past decade, survival rates in the BTT [bridge-to-transplant] population have steadily increased because of improvements in patient selection and management and the introduction of rotary blood pump technology,” the authors wrote.
“The results of this study indicate that patients with severe heart failure can be bridged to heart transplant with a small, levitated continuous-flow LVAD that is implanted within the pericardial space and that provides full circulatory support.”
Patients who were bridged to heart transplant had a six-month survival of 95 percent after transplant, the authors noted.
“In this first clinical study with a miniaturized LVAD placed in the pericardial space, the two-year survival rate was similar to that of heart transplant, which suggests that this long-term therapy is promising for the heart failure population,” the authors concluded.
In an accompanying editorial, Salpy V. Pamboukian, MD, of the University of Alabama at Birmingham, identified six major “hurdles” that have limited the widespread adoption of the technology over the last two decades.
The barriers included: device size, device durability, survival, driveline infections, thrombotic and bleeding complications and awareness of the benefits of this technology in the greater cardiology community and timely referral.
Pamboukian said that while the first three barriers have been cleared up with the current ventricular assist device technology, driveline infections, thrombotic and bleeding complications and awareness of the benefits of this technology still present clinicians with significant challenges.
Pamboukian said that disseminating scientific data that show the benefits of ventricular assist device therapy is crucial.
However, he noted that “the most powerful tool might be the patients themselves. As more patients receive VADs and return to their communities with improved quality of life,