A type of surgery which reshapes the scarred left ventricle, the main pumping chamber of the heart, and is often done in conjunction with heart bypass, not only failed to reduce deaths and hospitalizations in heart failure patients but also did not improve patients' quality of life compared to bypass alone after four years of follow-up, according to the results of a large international clinical trial funded by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.
These results from the Surgical Treatment for Ischemic Heart Failure Trial (STICH) are being presented at the American College of Cardiology's (ACC) 58th Annual Scientific Session in Orlando, Fla. The main mortality findings are also published online today in the New England Journal of Medicine (NEJM) and will appear in the April 23 print issue; findings from a substudy of STICH on quality of life will be published online on March 30 in the American Heart Journal.
"This study is of tremendous public health importance since it provides much needed clinical trial-based evidence to help physicians choose the best treatment for their heart failure patients," said NHLBI Director Elizabeth G. Nabel, M.D. "It is also a superb example of comparative effectiveness research, allowing evaluation of real world treatments in hopes of improving clinical care."
About 5 million people in the United States have heart failure, a chronic illness in which the heart is so weak it cannot pump enough blood to the body. The number of people with heart failure is growing, and each year, another 550,000 people are diagnosed for the first time. The most common causes of heart failure in the United States are coronary artery disease, high blood pressure, and diabetes.
The STICH trial is the largest study to date to compare the long-term benefits and risks for heart failure of both surgical ventricular reconstruction, a procedure developed in the last 25 years, and coronary artery bypass surgery (CABG) with CABG alone, which was first performed over 40 years ago.
The newer surgery was designed to eliminate the ballooned, scarred, and thinned area of heart muscle that can result after a heart attack and contributes to heart failure. In patients with heart failure, the heart expands like a balloon. The reshaping of the scarred ventricle attempts to return the heart to its original more compact shape, a procedure that improves pumping action and, therefore, blood flow. In bypass surgery, a healthy artery or vein from another part of the body is connected to the blocked coronary artery. The grafted artery or vein bypasses the blocked portion of the coronary artery, routing oxygen-rich blood around the blockage to the heart muscle.
The question asked by the STICH investigators was: Does the addition of surgical ventricular reconstruction offer added benefit to patients beyond bypass surgery or standard medical (drug and procedures) therapy?
In STICH, 1,000 patients from 96 medical centers in 23 countries were randomly assigned to undergo bypass surgery alone (499 patients), or bypass surgery plus surgical ventricular reconstruction (501 patients). All patients had moderate to severe heart failure; scarring of the heart; and poor (less than 35 percent) ejection fraction, the percentage of blood ejected from the left ventricle with each heart beat. All of the patients received intensive state-of-the-art medical therapy, including medications.
Although both types of surgeries improved symptoms such as angina and ability to exercise, after 4 years of follow-up, there were no significant differences between the two groups in combined rates of death and heart-related hospitalizations. There were 292 deaths/hospitalizations in patients assigned to bypass surgery compared to 289 deaths/hospitalizations in patients assigned to bypass with surgical ventricular reconstruction.
For the quality of life substudy, investigators conducted interviews with patients before and after their surgeries to collect information on physical and social limitations, satisfaction, and other measures of quality of life. Both treatment groups improved their quality of life after surgery but there was no difference between the two groups throughout 3 years of follow-up.
This substudy also looked at the economic consequences in the United States of having surgical ventricular reconstruction including whether the procedure would be cost effective. Information was collected on the length of surgeries, post-operative time in the intensive care unit, total length of hospital stay, rates of rehospitalization, hospital billing data, and physician costs. Costs were assigned using the 2008 Medicare Fee Schedule. Total hospitalization costs were $14,595 higher for bypass combined with the ventricular reconstruction.
"The results of the STICH trial demonstrate that routine use of surgery to reconstruct the left ventricle does not improve survival, hospitalization, quality of life or cost benefit over bypass surgery alone," said George Sopko, M.D., a medical officer at NHLBI and co-author of the mortality paper in NEJM. "There is still much to learn from the rich source of information provided by this trial, and we look forward to additional analysis of the results as patients continue to be followed."
Surgical reconstruction initially showed encouraging results and improvement in heart failure symptoms in some non-randomized studies, according to Sopko. "As with many initially promising procedures, further rigorous scientific testing is needed before full acceptance into medical practice," he added.
A second STICH trial, which is comparing the benefits and risks of bypass surgery with medical therapy alone, is ongoing with results expected to be reported in 2011.
The STICH mortality findings are being presented at the ACC meeting by Robert H. Jones, M.D., Mary and Deryl Hart Distinguished Professor of Surgery at Duke University Medical Center, Durham, N.C. The STICH economic and quality of life findings are being presented by lead investigator of the substudy Daniel Mark, M.D., M.P.H., director of outcomes research at the Duke Clinical Research Institute.
For more information on heart failure, visit http://www.nhlbi.nih.gov/health/dci/Diseases/Hf/HF_WhatIs.html.