An innovative program that maintains round-the-clock, on-site staffing of a cardiac catheterization laboratory dedicated to the treatment of heart attack has eliminated delays in the care for patients who arrive at the hospital during non-business hours, according to a study presented today at the Society for Cardiovascular Angiography and Interventions (SCAI) 33rd Annual Scientific Sessions.
The study, conducted at Aurora St. Luke's Medical Center in Milwaukee, showed that round-the-clock staffing of the cardiac catheterization laboratory-including an on-site interventional cardiologist-markedly reduced average "door-to-balloon" time, or the time between the patient's arrival at the emergency room and initial inflation of an angioplasty balloon in the blocked coronary artery. Equally important, researchers found that the door-to-balloon time was the same whether the patient underwent percutaneous coronary intervention (PCI) in the middle of the night or during daytime hours.
"This is important because PCI is the guideline-recommended way to treat a heart attack," said Fuad Jan, MD, a cardiovascular disease fellow at Aurora Sinai and Saint Luke's Medical Centers in Milwaukee, Wis. "Time is muscle. The faster you open the artery, the better."
Clinical guidelines recommend a door-to-balloon time of less than 90 minutes, even during off-hours. It has been a challenging goal for most hospitals to meet, however. Cardiac catheterization laboratories typically are staffed only during daytime hours. At night, a rotating team of interventional cardiologists, nurses and technologists takes call from home, typically with a mandate to report to the hospital within 30 minutes in an emergency. But there can be many sources of delay in assembling the cath lab staff, including the time it takes to transmit an electrocardiogram to the on-call cardiologist, page all the members of the cath lab team, and drive to the hospital, sometimes in inclement weather.
To improve overall door-to-balloon time, St. Luke's instituted round-the-clock cath lab staffing in April 2004. An interventional cardiologist and other members of the cath lab team remain in the hospital at all times, wearing special pagers that alert them to the arrival of a heart attack patient. The interventional cardiologist must report to the emergency room within five minutes of being paged.
To evaluate the effect of the program on door-to-balloon time, Dr. Jan and colleagues analyzed data from 611 consecutive patients who came directly to the St. Luke's emergency room between April 1, 2004, and June 30, 2009, with a serious type of heart attack known as an ST-elevation myocardial infarction (STEMI). Of these, 41 percent arrived during off-hours (weekends, holiday, and weekdays between 7:30 p.m. and 7:30 a.m.). All patients had PCI to open the blocked artery responsible for the heart attack.
Before the 24 x 7 program was launched, the median door-to-balloon time was about 99 minutes. After the program was in place, the median door-to-balloon time fell to 55 minutes, more than one-third lower than the established goal of 90 minutes or less. Overall, 89 percent of patients were treated within 90 minutes. In addition, there was no difference in door-to-balloon times during regular and non-business hours. In-hospital mortality was similar in the two groups (regular hours, 4.4 percent vs. off-hours, 4.5 percent; p=0.984).
"This is an important contribution, one that will become even more important as increasing numbers of patients are pre-diagnosed with a heart attack by paramedics, because patients will be getting to the cath lab even faster," said Timothy Henry, M.D., who did not participate in the study and is director of research for the Minneapolis Heart Institute Foundation. "The results of this study should stimulate every PCI center to actively consider this as an option."
A 24 x 7 program requires commitment from both physicians and the hospital, Dr. Jan said, but the benefits are clear. Not only do patients receive faster care, the hospital has seen a substantial increase in the number of heart attack patients transferred from neighboring hospitals that do not have round-the-clock cath lab coverage.
"This type of program does require a systems change," Dr. Jan said. "We have created a culture that makes it work."