Treating heart attack past recommended time may significantly increase risk of death

June 1, 2010

An examination of the treatment received by patients with myocardial infarction (heart attack) at 80 hospitals in Quebec indicates that those who received either primary percutaneous coronary intervention (PPCI; such as angioplasty) or fibrinolysis (administration of medication to dissolve blood clots) beyond the times recommended in international guidelines had a significantly increased risk of death within 30 days, along with an increased risk of the combined outcome of death or readmission for heart attack or heart failure at one year, according to a study in the June 2 issue of JAMA.

"Both primary percutaneous coronary intervention and fibrinolysis are well-recognized treatments for STEMI in international guidelines, and benefits are maximized when treatment occurs early," according to background information in the article. STEMI (ST-segment elevation myocardial infarction) is a certain pattern on an following a heart attack. "However, randomized trials and selective registries are limited in their ability to assess the effect of timeliness of reperfusion on outcomes in real-world STEMI patients."

Laurie Lambert, Ph.D., of the Que­bec Healthcare Assessment Agency, Montreal, Canada, and colleagues conducted a province-wide evaluation of STEMI care in Que­bec (population, 7.8 million) to determine the use of reperfusion treatments (such as PPCI or fibrinolysis) and their delays and whether STEMI reperfusion treatment outside of the guideline-recommended delays was associated with poorer outcomes than treatment within recommended delays. The researchers analyzed data of STEMI care for 6 months during 2006-2007 in 80 hospitals in Quebec. Maximum delays rec­ommended in international guidelines for PPCI are 90 minutes; 30 minutes for fibrinolysis.

Of the patients treated with acute reperfusion (n = 1,832), 78.6 percent (1,440) underwent PPCI and 21.4 percent (392) received fibrinolytic therapy. Among patients who underwent PPCI, the median (midpoint) door-to-balloon time was 110 minutes. PPCI was untimely (greater than 90 minutes) in 68 percent of patients. For patients who received fibrinolysis, the median delay was 33 minutes, and untimely (greater than 30 minutes) in 54 percent of patients. Incidence of the combined outcome (death or readmission for or heart attack) at 1 year was 13.5 percent for fibrinoly­sis patients and 13.6 percent for PPCI patients.

"When the 2 treatment groups were combined, patients treated outside of recommended delays had an adjusted higher risk of death at 30 days (6.6 percent vs. 3.3 percent) and a statistically nonsignificant increase in risk of death at 1 year (9.3 percent vs. 5.2 percent) compared with patients who received timely treat­ment. Patients treated outside of recommended delays also had an adjusted higher risk for the combined outcome of death or hospital readmission for congestive heart failure or acute [] at 1 year (15.0 percent vs. 9.2 percent). At the regional level, after adjustment, each 10 percent increase in patients treated within the recommended time was associated with a decrease in the region-level odds of overall 30-day mortality," the authors write.

"Our study, while consistent with reg­istry and clinical data associating longer treatment delays with poorer out­comes, is novel and robust in several ways. Above all, it represents not a sam­pling but more than 95 percent of all STEMI patients within a large and complex sys­tem of care and provides very recent information that transcends the rela­tive selectivity of randomized clinical trials and most registries."

" … we believe this evaluation repre­sents a needed contribution to the evi­dence base for deriving clinical practice guidelines and an important advance in knowledge of the outcomes associated with contemporary processes of STEMI care. This 'real-world' information is rel­evant both clinically and from a perspec­tive of evidence-based health care policy and planning, pointing to the lifesaving potential for approaches that focus on offering the most timely reperfusion treatment to patients with STEMI," the researchers write.

They add that time, rather than mode of reperfu­sion, emerges as a critical determinant of outcome in this systematic evalua­tion of STEMI care. "Regardless of reper­fusion strategy, patients treated be­yond maximum recommended delays had increased mortality."

More information: JAMA. 2010;303[21]:2148-2155.

Related Stories

Recommended for you

Expert: Be concerned about how apps collect, share health data

October 20, 2017
As of 2016 there were more than 165,000 health and wellness apps available though the Apple App Store alone. According to Rice University medical media expert Kirsten Ostherr, the Food and Drug Administration (FDA) regulates ...

Three million Americans carry loaded handguns daily, study finds

October 19, 2017
An estimated 3 million adult American handgun owners carry a firearm loaded and on their person on a daily basis, and 9 million do so on a monthly basis, new research indicates. The vast majority cited protection as their ...

More teens than ever aren't getting enough sleep

October 19, 2017
If you're a young person who can't seem to get enough sleep, you're not alone: A new study led by San Diego State University Professor of Psychology Jean Twenge finds that adolescents today are sleeping fewer hours per night ...

Across Asia, liver cancer is linked to herbal remedies: study

October 18, 2017
Researchers have uncovered widespread evidence of a link between traditional Chinese herbal remedies and liver cancer across Asia, a study said Wednesday.

Eating better throughout adult years improves physical fitness in old age, suggests study

October 18, 2017
People who have a healthier diet throughout their adult lives are more likely to be stronger and fitter in older age than those who don't, according to a new study led by the University of Southampton.

Global calcium consumption appears low, especially in Asia

October 18, 2017
Daily calcium intake among adults appears to vary quite widely around the world in distinct regional patterns, according to a new systematic review of research data ahead of World Osteoporosis Day on Friday, Oct. 20.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.