Heart patients getting interventions late, raising mortality risk
A new report finds only one out of ten patients with acute heart attack are getting procedures to open blocked arteries within the recommended time. In a new study, researchers cite the need to understand why it’s happening and what can be done to improve door in, door out (DIDO) time for STEMI, or acute heart attack, victims.
One of the reasons is that only 75 percent of hospitals in the United States have the capability to perform those interventions, but the study authors say getting heart attack patients to another hospital for needed treatment should be achievable.
Patients with STEMI, or ST elevation MI, should be treated within 90 minutes of hospital arrival time to open blocked arteries, but only 13 percent of patients are transferred to a treating hospital within the recommended 30 minutes to facilitate.
The study authors explain, "Primary percutaneous coronary intervention is the preferred method of reperfusion (restoration of blood flow to the heart) for patients with ST-segment elevation myocardial infarction [STEMI; a certain pattern on an electrocardiogram following a heart attack]”
Study finds need for system wide boost in heart attack treatment performance
The study, published in the Journal of the American Medical Association, found the average DIDO time for heart attack patients studied was 68 minutes.
The delay in treatment time was found to increase mortality rate in the hospital by 5.5 percent, compared to patients who receive a stent or angioplasty within 30 minutes.
Twenty five percent of hospitals lack the capability to perform angioplasty and stent procedures. The study authors cite several other factors that interfere with timely hospital transfer for coronary interventions for STEMI patients that they say needs attention and improvement.
The study showed patients who get to a receiving hospital within 30 minutes were more likely to receive PCI, compared to those whose arrival time was greater than 30 minutes (95.9 vs. 90.5 percent). The analysis included 14,821 patients with STEMI, transferred to 298 STEMI receiving centers. The patients were part of the Intervention Outcomes Network Registry (ACTION) Registry-Get With the Guidelines between January 2007 and March 2010.
The average time it took to get to a STEMI receiving hospital was 68 minutes, with just 11 percent transferred within the 30 minute time frame.
Fifty six percent of those had a transfer time greater than an hour and 35 percent didn’t arrive until an hour and a half after initial presentation to a hospital.
Door to time of balloon angioplasty time (DTB) was shorter overall for patients transferred within 30 minutes or less.
The study is one of the first to look at time of hospital arrival and time of transfer out for treatment of acute heart attack.
Study author Tracy Y. Wang, M.D., M.H.S., M.Sc., of Duke University Medical Center, Durham, N.C. said, "One of the remarkable things about this study is that it looks like 30 minutes is achievable, albeit in a very surprisingly small number of patients [currently].”
She says problems include getting and EKG to identify STEMI, arranging for transfer of patients to a STEMI treatment hospital and ensuring they will go right to the cath lab where the procedures are performed.
Wang noted, "The part that this study doesn't quite address but will be really quite important to tease out in future projects will be the system-level factors that really have an impact on the door-in to door-out times."
The study shows hospitals can help reduce mortality rates for heart attack patients by getting them to a transferring hospital for intervention in a timely fashion. Currently, just ten percent of STEMI patients are making it fast enough to where they need to be.
JAMA: 2011;305(24):2540-2547. doi: 10.1001/jama.2011.862
"Association of Door-In to Door-Out Time With Reperfusion Delays and Outcomes Among Patients Transferred for Primary Percutaneous Coronary Intervention"
Tracy Y. Wang, MD, MHS, MSc et al
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