STITCH: Surgical ventricular reconstruction plus CABG no better than CABG alone in heart failure patients
A surgical procedure that reduces the size of a scarred,
enlarged heart did not improve long-term survival or reduce the number of hospitalizations
in patients with heart failure, according to research presented at the American
College of Cardiology's 58th annual scientific session and simultaneously published
in the New England Journal of Medicine.
The first phase of the Surgical Treatment for Ischemic
Heart Failure (STICH) trial showed that patients who had surgical ventricular
reconstruction (SVR) in addition to coronary artery bypass grafting (CABG) fared
no better over an average of four years of follow-up than patients treated with
CABG alone.
"Over the last decade, as we have been doing better at
managing the myocardial infarctions that cause injury to the heart, these scars
have gotten smaller and smaller," said Robert H. Jones, M.D., Mary and Deryl Hart
Distinguished Professor of Surgery at Duke University Medical Center, Durham,
NC. "Now we know that with good, intensive medical therapy and very good revascularization,
there is no intrinsic value to SVR over bypass surgery alone."
Surgical ventricular reconstruction returns the ventricle
to a more normal, compact size. At a smaller size, the heart experiences less
stress and strain and, like a healthy heart, might regain the ability to temporarily
expand to meet the body's demands for increased cardiac output. Previous studies
have shown that one of the strongest predictors of survival in patients with heart
failure is the size of the heart at the end-systolic volume.
For the study, investigators recruited 1,000 patients
from 96 medical centers in 23 countries. Patients were required to have an ejection
fraction of ≤
35 percent, coronary artery disease the surgeon felt could be well
managed by CABG, and an area of scarred, dysfuctional tissue in the anterior-apical
region. About half of patients had moderate-to-severe angina. Heart failure was
deemed moderate-to-severe in a similar proportion, and more than 60 percent had
triple-vessel disease. The median age was 62, and 85 percent of patients were
men.
Patients were randomly assigned to undergo CABG alone
(499 patients), or CABG plus SVR (501 patients). All patients received intensive
medical therapy. Both surgeries improved symptoms and exercise capacity, and SVR
was successful in reducing end-systolic volume index by 20 percent, compared to
3 percent with CABG. However, after a median follow-up of 4 years, there were
no differences between the two groups in combined rates of death or hospitalization
for cardiac causes (56 percent among patients in the CABG group and 57 percent
among patients treated with both CABG and SVR).
"This is the first time that a proposed new heart operation
has been tested in this way," Jones said. "Our findings emphasize the importance
of taking what appear to be medical breakthroughs and subjecting them to very
rigorous comparisons with the best available therapy."
A second report from the STICH trial presented at ACC
and published online in the March 30 in the American Heart Journal, concluded
that that SVR increases costs without improving quality of life or providing other
clinical benefits.
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.
Investigators have already enrolled more than 1,200 patients
in the next phase of the STICH trial. It will answer an even more crucial question:
whether bypass surgery itself is effective in improving long-term survival in
patients with heart failure who are already receiving the best possible medical
therapy.
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