MONDAY, Oct. 31, 2005 (HealthDay News) -- The time and effort spent to develop guidelines for cardiac procedures pays off in better results for patients, a new study finds.
The guidelines are developed jointly by the American Heart Association and the American College of Cardiology. They are recommendations that cover a number of clinical issues, from medication to surgery.
"It has not been shown before that guidelines covering a particular medical procedure might or might not affect outcomes," said Dr. H. Vernon Anderson, lead author of the study that appears in the Nov. 1 issue of Circulation. "What we learned, as everyone had hopefully anticipated, was that if you adhere to the guidelines, the outcome will be better."
The study analyzed the impact of the guidelines, issued in 2001, for the selection of patients for procedures that are formally called percutaneous coronary interventions -- angioplasty, in which a balloon-tipped catheter is used to keep cholesterol deposits from blocking an artery; and stenting, in which a flexible tube is implanted to keep the artery open.
The guidelines divide patients into four classes, ranging from those whose condition makes them most likely to receive the greatest benefit from a procedure to those judged least likely.
Led by Anderson, who is a professor of medicine at the University of Texas Health Science Center in Houston, the researchers looked at results of procedures performed on more than 400,000 patients in 393 hospitals.
They found that 64 percent of the procedures were done on patients most likely to benefit; 21 percent on those patients somewhat less likely to benefit; 7 percent on those even less likely to benefit; and 8 percent on those judged least likely to benefit.
The success rate was 92.8 percent in the first group, 91.7 percent in the second group, 89.0 percent in the third group, and 85.5 percent in the last group.
The rate of complications and deaths showed the same pattern, with only 1 percent of patients in the most-likely-to-benefit group suffering heart attacks before hospital discharge, compared to 1.5 percent in the least-likely-to-benefit group. The death rate was 0.5 percent for the first group, 1.7 percent in the last group.
"The differences are small but significant, and show for the first time that guidelines criteria are related to real-world outcome," Anderson said.
So why do some cardiologists go against the guidelines?
"Physicians may feel that their judgment in an individual case is better," said Dr. Gregg Fonarow, a professor of cardiovascular medicine at the University of California, Los Angeles, and a spokesman for the American Heart Association. "But we see in this large data set that these guidelines are quite applicable."
And guidelines can change "as new clinical trial evidence becomes available," Fonarow said. For example, the guidelines for treatment of heart failure were first released in 1995, but they were updated in 2001, and again earlier this year.
In the end, "guidelines are only a suggestion," Anderson said. "It is always up to the individual physician to factor these things into clinical decisions."
For more on the guidelines program, visit the American Heart Association.