NEW ORLEANS Roughly speaking, the healthy heart is shaped something like a football. Beset by congestive heart failure, the heart begins to dilate, expanding and reshaping to take on a spherical "basketball" look, according to Douglas Mann, MD, a cardiologist affiliated with the Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine (both Houston).
Returning this sick heart to a more "energetically favorable football" shape is accomplished by the CorCap Cardiac Support Device (CSD) from Acorn Cardiovascular (St. Paul, Minnesotta), Mann reported at a late-breaking trial session during the American Heart Association (AHA; Dallas) annual meeting here. And this reshaping "reverses the natural history of HF [heart failure], as indicated by an improvement in LV [left ventricle] size and shape, and improved clinical score, fewer major cardiac procedures and improvements in quality of life," according to the study of the CSD device presented by Mann.
The CSD consists of a mesh material, proprietary to Acorn, placed jacket-like around the heart via surgical procedure. The mesh was designed to be what Mann called a "highly complex piece of engineering that encourages an elliptical shape," with that reshaping helping to "rest and heal" and "unload" the heart.
Most importantly, he said that use of the CSD may provide a "breakthrough in the treatment of this problem that offers an alternative between drugs and electrotherapy procedures." Its invasiveness, also, falls between drugs and highly invasive transplant or VAD procedures, he told Cardiovascular Device Update.
The multi-center study reported on by Mann enrolled 300 patients at 29 centers across North America with NYHA Class III/IV HF and dilated cardiomyopathy. It was the most extensive controlled evaluation of a surgical treatment for heart failure ever conducted, according to Acorn. Patients participating in the trial had symptomatic heart failure with enlargement of the heart and were being treated with optimal drug therapy, including beta-blockers and ACE inhibitors.
Of this group 193 underwent mitral valve repair/ replacement (MVR) and were randomized either to MVR alone or MVR plus implantation of the CSD. The remaining 107 patients were randomized to either continued optimal medical therapy alone or with the CSD device. Patients were followed for 12 months after the last patient was enrolled, with a median follow-up of 22 months. The primary endpoint was a clinical composite with patients classified as improved, same or worsened, based upon the occurrence of death, a major cardiac procedure indicative of HF progression and a change in NYHA class.
The CSD group showed improvements in several categories. This group had more patients improved according to NYHA class (38% vs. 27%) and fewer patients "worsened" (37% vs. 45%). The CSD group had fewer follow-on major cardiac procedures (such as heart transplant, implantation of a ventricular assist device or need for electrical stimulation therapy), compared to the control group. And using a quality-of-life assessment, the CSD group reported greater improvement in quality of life over the control group.
Mann's presentation received strong interest from a large group of interested media and considerable skepticism from several about at least two of the findings: the study reported no difference between the two groups in terms of repeat hospitalizations or adverse events, and there was no significant improvements in terms of ejection fraction. In answer, he downplayed the overall significance of ejection fraction for understanding the condition of this type of patient, a judgment supported by Raymond Gibbons, MD, moderator of the late-breaking trials session.
Mann said that, of all the measures, the "heart size is the most important predictor of where the patient is going to go" in terms of the progress of his or her disease. He further expressed his "suspicion" that in studies with "longer-term follow-up, we will see differences emerge."
He predicted that Acorn will make application to the FDA for approval of the CorCap device sometime in 2005. The CorCap mesh device "is not for everyone," Mann emphasized more than once during his presentation. Its use is more applicable to what he termed as "moderate" cases of heart failure patients - particularly those "not doing well on medical therapy" and ranging from 1 million to 1.5 million of the 5 million heart failure patients in the U.S. "It fits a middle ground," he said, does not rule out later interventions such as heart transplant and is "synergistic" with other medical therapies. That synergy, he noted, was represented in the trial's strategy of combining CSD with mitral valve repair/replacement. He also noted the possibility of its potential combination with resynchronization therapy.
In a statement, Acorn emphasized the need for the CorCap, given the rapid growth in heart failure cases - 550,000 each year and a total of 25 million sufferers worldwide. Rich Lunsford, president and CEO, characterized the trial results as marking "the beginning of a new era in heart failure therapy. In the past, patients with enlarged hearts had very few treatment options. The positive trial results bring us one step closer to making a breakthrough therapy widely available to heart failure patients."