Should heart attack care be
more like trauma care?
Newswise — In a heart attack,
every minute counts. But should patients spend a few more of those
minutes getting to a hospital that can provide the most advanced
treatment, rather than just the closest hospital?
That question is at the heart of a
current debate among heart specialists: whether to make heart attack
care more like trauma care, with ambulance crews taking certain
patients to specialized hospitals that can perform emergency heart
procedures, rather than stopping at the closest hospital.
A new study looks at a crucial
issue in that debate: how close Americans live to hospitals that can
perform angioplasty, which is considered the best treatment for the
form of heart attack called STEMI, if it’s done quickly. Only a
fraction of American hospitals perform angioplasties, which re-open
blocked blood vessels in the heart and can be done electively to
prevent a heart attack or urgently to treat one.
The new research shows that nearly
80 percent of Americans live within an hour’s ambulance trip of an
angioplasty-performing hospital. The University of Michigan and Yale
University research team made the finding by combining and analyzing
census data, hospital locations, driving distances and estimated
driving times.
The researchers also found that
the closest hospital to about 58 percent of Americans doesn’t do
angioplasty. But the extra drive time to an angioplasty hospital
would be less than 30 minutes for most of them, though many patients
in rural areas would have farther to go.
The research will be published
March 8 in the journal Circulation, and will also be presented March
13 at the annual meeting of the American College of Cardiology.
“There are many more issues
involved in regionalizing heart attack care, with proximity to
specialized hospitals being necessary, but not sufficient, for
making such a system feasible,” says lead author Brahmajee
Nallamothu, M.D., MPH. an assistant professor of internal medicine
at the U-M Medical School, researcher at the VA Ann Arbor Healthcare
System and member of the U-M Cardiovascular Center.
“This study puts in perspective
what it would mean for patients to be diverted from the closest
hospital to one that performs angioplasty.” Says Harlan Krumholz,
M.D., senior author and professor at the Yale School of Medicine.
“For some patients the difference in time is trivial, for others it
may add a potentially dangerous delay to their treatment. It
suggests that a national policy needs to take into account local
geography.”
Adds co-author Eric Bates, M.D., a
U-M professor of cardiovascular medicine who has studied emergency
heart attack care for years, “This analysis is a first step. It
shows that the majority of patients don’t have geographic
limitations that would obstruct the concept of regionalization, but
it doesn’t address implementation and economic issues.”
One of the major issues in the
regionalization debate is the ability of ambulance crews to
distinguish STEMI heart attacks from other problems using portable
electrocardiogram equipment, since only STEMI patients have been
shown to derive more benefit from emergency angioplasty than from
fibrinolytic (clot-busting) drugs that can be given at most
hospitals.
Research by the new paper’s
authors and others also continues to show that emergency angioplasty
holds the most benefit for patients when it’s performed by
experienced doctors at hospitals where it is the “default” STEMI
treatment and when it can be performed in a timely way.
For these reasons and more,
Nallamothu notes that the regionalization of heart attack care will
probably have to happen on a local and state basis, rather than
nationally. Already, he says, several cities such as Boston and
states such as Maryland have started to implement new protocols for
ambulances and hospitals that allow quick diagnosis of STEMI and
immediate transport of STEMI patients to hospitals that can perform
emergency angioplasty.
The new study is based on data
from the 2000 U.S. Census broken down by individual tracts, the
American Hospital Association’s database of hospitals’ locations and
the services they provide, Medicare data on angioplasty billing by
hospitals, and driving times, distances and road routes derived from
commercial geographical mapping software. The researchers added in
time for the dispatching of an ambulance and the assessment and
loading of a patient at the scene by the emergency medical
personnel.
In all, 1,176 hospitals provided
angioplasty, about 25 percent of all acute-care hospitals at the
time. The number and percentage have almost certainly grown since
2001, as more states allow hospitals to perform angioplasty even if
they don’t have open-heart surgery capability in case of a
complication.
The median driving time to an
angioplasty hospital was calculated to be 11.3 minutes, or a
distance of 7.9 miles. Driving times and distances were calculated
using road routes, not “as the crow flies.”
The researchers also calculated
the “bypass delay” – the additional minutes an ambulance would have
to drive to get to an angioplasty hospital if it wasn’t the closest
hospital. The median was 10.6 minutes, and 9.7 miles. A total of
73.8 percent of adults whose ambulances would have to bypass another
hospital to get to an angioplasty hospital would be able to get
there within 30 minutes, and 90 percent would get there within 60
minutes of additional driving time.
While 79 percent of American
adults lived within a 60 minute ambulance trip of an angioplasty
hospital, there was tremendous variation across the nation. In the
mid-Atlantic states, New England, and West Coast states, more than
82 percent of adults were within an hour of such a hospital, while
in the plains states and desert Southwest, the percentage was in the
60s. No matter what state they lived in, only 47 percent of rural
adults were within an hour’s drive of an angioplasty hospital. And
rural adults also faced longer “bypass delays” than adults in
suburban and urban areas.
In addition to Nallamothu,
Krumholz and Bates, the study’s authors are Yongfei Wang, M.S. and
Elizabeth Bradley, Ph.D. of Yale.