Date: May 8, 2008

Summary: Even though it may take longer to start treatment for heart attack patients who arrive at the hospital after 7 p.m. or on weekends, this does not appear to affect the risk of dying in the hospital, according to a study evaluating the care of 62,814 patients.

Journal: Circulation

Journal citation: Circulation 2008;117:2502-2509

Read the original article: http://circ.ahajournals.org/cgi/content/full/117/19/2502

Why it’s important: Heart attack, also called acute myocardial infarction (AMI), is a leading cause of death in the United States. Understanding the factors that may affect the risk of dying from a heart attack could reduce deaths and improve health.

What’s already known: Several previous studies have shown that patients admitted to the hospital during “off hours” because of a heart attack were less likely to receive guideline-based care. However, these studies have been inconsistent in their findings and have been limited because they focus only on certain heart attack patients or certain regions, or reflect noncontemporary treatment practices.  

How this study was done: The study’s authors, from various medical practice groups across the United States, used data from a national data registry called GWTG–CAD (Get With The Guidelines–Coronary Artery Disease), which was created by the American Heart Association to encourage hospitals to follow approved treatment guidelines for CAD patients. The registry includes information from hospitals throughout the United States. “Regular hours” were defined as weekdays from 7 a.m. to 7 p.m. and “off hours” as weeknights, weekends and holidays. The authors noted whether patients received guideline-based treatment practices including aspirin and beta-blockers within 24 hours of arrival, and whether invasive procedures were performed; these procedures included heart catheterization, angioplasty (using a balloon to open up a clogged artery), use of a stent (tiny metal coil) to keep the artery open, and bypass surgery (surgery to bypass the clogged coronary artery causing the heart attack). The authors evaluated when these procedures were done compared to when the patients arrived at the hospital. Then they correlated these times with outcomes (whether the patients lived or died) in the hospital.

What was found: Slightly more than half of patients (54.1 percent) with heart attack arrived during off hours. These patients were slightly more likely to receive beta-blockers within the guideline-approved timeline but not aspirin therapy. Additionally, off-hours heart attack patients were 7 percent less likely to receive emergency procedures such as angioplasty or bypass surgery. However, these differences had no significant effect on whether the patients died while they were in the hospital.

The study’s lead author, Hani Jneid, M.D., an interventional cardiology physician-in-training at Massachusetts General Hospital in Boston, said “This seems to run counter to previous study findings. Future studies should not only strive to confirm or disprove these results, but also examine variables that might affect the interplay of care and outcome with arrival time.”

The bottom line: Although there may be a slight delay in care for heart attack patients who arrive during a hospital’s off hours, time of hospital arrival appears to have no significant effect on whether a patient will die from a heart attack or not while in the hospital.



This content is reviewed regularly. Last update 07/14/08.