Surgery to reshape damaged hearts, which excludes scarred muscle tissue and restores the left ventricle’s normal shape, may provide long-term benefits for certain patients with advanced heart failure, according to a new study in the Oct. 6, 2004 issue of the Journal of the American College of Cardiology.
“Ventricular restoration is a safe and effective procedure that amends the standard treatment of coronary artery bypass graft surgery, mitral valve repair or replacement, and conventional medical treatment,” said Gerald D. Buckberg, M.D. from the UCLA Medical Center in Los Angeles. “Surgical change in ventricular size and shape in this registry group of 1,200 patients alters the downward trajectory of mortality and repeat hospitalization that characterizes current therapy.”.
The main pumping chambers in the hearts of these patients had ballooned out due to damage done by heart attacks. During the surgical ventricular restoration procedures, surgeons identified the margins of healthy heart tissue that surrounded the damaged muscle tissue. Then they pulled the healthy tissue together, restoring the left ventricle to a more normal shape.
For this study, researchers, including lead author Constantine L. Athanasuleas, M.D., F.A.C.C., at the Norwood Clinic and Kemp Carraway Heart Institute in Birmingham, Ala., analyzed results from more than a dozen centers in the United States, Europe, Asia and South America that performed surgical ventricular restoration on 1,198 patients between 1998 and 2003. Two-thirds of the patients had advanced heart failure at the time of surgery (New York Heart Association functional class III or IV).
“The normal heart is elliptical and shaped like a football, while the dilated heart is spherical in shape, like a basketball. The surgical procedure alters size and shape to make the dilated basketball shaped heart smaller and restore the more normal football shape,” Dr. Buckberg said.
Using standard statistical methods to analyze the experience of patients so far, the researchers estimated a five-year survival rate of almost 70 percent (68.6 ± 2.8%). On average, the patients’ ejection fractions (a measure of the heart’s pumping ability) increased 10 percent (from 29.6 ± 11.0% before the surgery to 39.5 ± 12.3% after) and the size of the chamber was decreased as ventricular volume was reduced from 80 to 57 milliliters per meter squared. The heart failure class ratings improved as well. Prior to surgery, 67 percent of the patients were in class III or IV, but after the procedure, 85 percent were in class I or II. About 5 percent of the patients died within 30 days of surgery.
In contrast to some earlier surgical techniques, this procedure does not remove heart muscle. Also, the surgeons carefully identified the margins of damaged tissue, in order to protect the remaining healthy heart muscle.
Every patient who got the surgery at the participating centers was included in the analysis. There was no control group, but Dr. Buckberg said the results are dramatically better than usually expected for patients with advanced heart failure who do not undergo surgery. He said for patients with class III or IV heart failure, a 25 or 30 percent annual death rate is common.
“By the time three years go by, 70 to 80 percent of the people are gone. But with this operation, after five years of follow up, 70 percent of Class III patients and 50 percent of Class IV patients are still alive. That’s a very dramatic difference,” he said.
Dr. Buckberg also noted that the surgery seems to work just as well for patients older than 75 as it does for younger patients. He offered a checklist for those considering surgical ventricular restoration.
“Evaluation of three areas is critical to determining if restoration should be considered. First, the area of the heart chamber that is damaged by the patients’ ejection fractions (a measure of the remaining muscle must be assessed, as ventricular volume is reduced. This is done by looking at these regions by ventriculogram (a type of imaging scan), MRI or ultrasound. Third, the ventricular volume must be measured, and this is also done by ventriculogram, MRI or echo study,” Dr. Buckberg said.
Robert H. Jones, M.D., F.A.C.C., with the Duke University Health System, who was not connected with this study, called the results important and positive enough to justify further study. He is part of a team that has begun a study of heart failure patients undergoing bypass surgery that randomly assigns some of them to also get a ventricular restoration procedure.
“The big strength of their article is that it gives you some benchmark figures that make the operation look sufficiently promising that it does need to be evaluated,” Dr. Jones said. “The article is not definitive and doesn’t claim to be, as it is observational and doesn’t have any comparative information. So if you had done a bypass or mitral valve operation in the absence of the surgical ventricular restoration, would the patients have been better, worse or the same? That’s the question we are addressing in a randomized trial.”