March 21, 2002
ATLANTA, Georgia (ACC) -- Recent analysis of data from the MIRACLE (Multicenter InSync
Ran-domized Clinical Evaluation) study shows that cardiac
resynchronization therapy (CRT) reduces the need for
hospitalization and may improve survival, according to William
T. Abraham, MD, from the University of Kentucky, who reported
the findings at a news conference on Monday,
March 18, 2002.
This is in addition to the therapy’s previously proven affects
on improving exercise endurance and enhancing wellbeing, Dr.
Abraham said. MIRACLE was the first large-scale, randomized,
double-blind control trial of CRT for heart failure.
“In looking at measures of heart failure hospitalization, the
risk of hospitalization for worsening heart failure was
significantly reduced by 50 percent,” he said. “CRT was also
associated with a significant reduction in hospital length of
stay, with the average length of stay for the control group
seven days and for the group receiving CRT 3.4 days.”
Looking at the total days of hospitalization for heart failure
over six months, it was reduced by 77 percent, Dr. Abraham
reported. Other measures of heart failure morbidity, such as
worsening heart failure requiring the use of IV medication, also
showed significant reduction.
“The combined endpoint of death or worsening heart failure
requiring hospitalization was significantly reduced by 40
percent among those receiving CRT,” he said. “From this
analysis, we can conclude that CRT reduces risk of heart failure
hospitalization as well as other measures of worsening heart
failure.”
However, he noted, observed improvement in combined measures of
heart failure morbidity and all-cause mortality awaits
confirmation by ongoing, large-scale morbidity and mortality
trials.
“There was no significant difference between CRT and no CRT in
terms of effect on mortality,” Dr. Abraham said, explaining that
the study group was too small to assess mortality.
Dr. Abraham also reported on a small study from the University
of Florence in Italy, conducted by Dr. Luigi Padeletti and
colleagues, that observed the effects of CRT on cardiac
structure, function, and neurohormones. Researchers found a
significant correlation between reduction in tumor necrosis
factor-a and improvement in the volume of blood the heart was
able to pump with each contraction, as well as in quality of
life.
“CRT was shown to improve patient outcomes and appears to
reverse some of the adverse effects of heart failure related to
structural changes and augmentation of the cytokine systems,” he
said. |