Time-to-treatment is important to success of angioplasty treatment

Sep 28 2005

An in-depth look at hospitals that reduced treatment delays highlights steps other hospitals could take to provide rapid angioplasty treatment to heart attack patients, according to a new study in the Oct. 4, 2005, issue of the Journal of the American College of Cardiology.

"Time-to-treatment is important. The effectiveness of angioplasty in the treatment of heart attacks is highly dependent on the timeliness of therapy. There are some hospitals that are achieving great performance; and if you break down their approach, you can see many key strategies that can be applied more broadly, so perhaps best practice can become typical practice," said Harlan M. Krumholz, M.D., S.M., F.A.C.C. from the Yale University School of Medicine in New Haven, Connecticut.

American College of Cardiology and American Heart Association treatment guidelines say hospitals equipped to perform emergency angioplasty procedures should try to reopen blocked blood vessels of heart attack patients within 90 minutes of a patient's arrival. The study authors produced a flow chart that outlines the steps successful hospitals took to meet that "door-to-balloon" time standard. Key steps include:

• Equip and train ambulance crews to perform electrocardiograms (ECGs) in the field
• Use the "pre-hospital" ECGs to trigger activation of angioplasty teams
• Allow emergency medicine physicians make the activation call without waiting for a cardiologist to confirm a heart attack diagnosis

The researchers also said that the hospital staffs accepted the fact that there were occasional "false starts" in which angioplasty teams would get ready and then be told to stand down. The events were seen as a reasonable tradeoff for dramatically trimming door-to-balloon times and reducing heart muscle damage in those patients who were indeed having heart attacks.

The researchers used a national registry of heart attack treatment performance to identify hospitals that met the 90-minute door-to-balloon angioplasty treatment standard. Then they did indepth onsite interviews with staff at 11 hospitals that had achieved the greatest reductions in treatment times over a four-year period.

The authors said that effective collaboration between ambulance crews, emergency medicine staff and angioplasty teams could trim door-to-balloon times to 60 minutes or less.

"Not all hospitals may be able to replicate this idealized flowchart; but we believe that there will be useful and practical value for all hospitals," Dr. Krumholz said.

"This approach also helps us see what has worked in the real world, not just what might be designed as ideal interventions and implemented in a controlled study, so it gives us some faith that the efforts are feasible; not easy, but achievable," added lead author Elizabeth H. Bradley, Ph.D., also from the Yale University School of Medicine.

The researchers also had advice for patients who suspect they may be having a heart attack: call 9-1-1, instead of driving to a hospital.

"The value of activating 911 is not that an ambulance will drive faster than a family member taking you in the car, but rather that medical assessment and treatments can begin earlier, en route to the hospital," Dr. Bradley said.

Dr. Krumholz said the practices they identified do not necessarily cost more.

"Most of the innovations in the flowchart are about working smarter, not necessarily harder or with more staff. It is about proper organization and flow. It is about planning and preparing and communicating to everyone what is expected and when," Dr. Krumholz said.

"Real improvement in such a complex treatment process involves collaboration and coordination of many departments and disciplines, in ways more simple clinical processes may not require. This is bringing a systems mentality to medicine, whereby exceptional performance is not a property of individual clinicians but a property of more ideally designed systems in which individuals work," Dr. Bradley added.

However, Dr. Krumholz noted that many ambulance crews do not have the equipment or training to perform ECGs in the field. He said this study shows investing in pre-hospital ECG capabilities would improve performance.

Christopher B. Granger, M.D., F.A.C.C., from the Duke University Medical Center, who was not connected with this study, said that it provides important new information. While clinical trials show what things should be done, and clinical practice registries reveal gaps between that ideal practice and what's actually happening in hospitals, this study addresses the critical practical issue of how practice can be improved.

"We don't have much information on how we can improve; and this study begins to bridge that gap by systematically describing what aspects of the approach hospitals take seems to be related to better performance," Dr. Granger said.

W. Douglas Weaver, M.D. from the Henry Ford Heart & Vascular Institute in Detroit, Michigan, who also was not part of this research team, said the study affirms what was known about how to reduce treatment times.

"It takes teamwork to achieve the best results, a collaboration between emergency services, paramedics and cardiologists and catheterization lab personnel. I'd also say that the value of a pre-hospital ECG is that 'a picture is worth a thousand words.' When medics and doctors see diagnostic ST segment elevation; they become focused on the problem and things happen quickly," Dr. Weaver said.