Aspirin Improves the Long-Term Results of Coronary Angioplasty
Angioplasty will be used on more than 400,000 people this year
to help unclog arteries in the heart. A major study led by Jefferson cardiologists
found that aspirin therapy after angioplasty provides a long-term benefit
to patients and reduces the risk of heart attack. Aspirin works by inhibiting
the activation of clotting cells, called platelets, in the circulating blood.
The study findings appear in the December 1st issue of the journal Circulation.
"Previous studies have shown the importance of administering aspirin
before balloon angioplasty in order to minimize complications at the time
of the procedure," says Michael Savage, MD, director of Jefferson's
Cardiac Catherterization Laboratory and associate professor of medicine
at Jefferson Medical College, and lead author of the study. "Our study
demonstrates, for the first time, the importance of patients continuing
to take aspirin at home for at least six months after the procedure."
The study was a multicenter trial. Seven hundred and fifty-two patients
were randomly assigned to aspirin (325 mg daily), sulotroban (a potential
"super aspirin"), or placebo, starting the therapy within six
hours before coronary angioplasty and continuing for six months. Results
showed the group receiving aspirin had far fewer heart attacks (1.2 percent
for aspirin and 5.7 percent for placebo in the months following treatment).
Patients treated with aspirin also had significantly lower long-term clinical
failure (defined as clinically important restenosis, or reclogging of the
arteries, bypass surgery, heart attack, and death). Treatment failure occurred
in 30 percent (49 of 162) of the aspirin group and 41 percent (71 of 175)
of the placebo group.
"We now know that this simple treatment can substantially improve the
long-term outcome of our patients," says Dr. Savage. "For people
who have undergone coronary angioplasty during the past six months, the
take-home message is that you should be taking an aspirin every day. If
aspirin has not been prescribed, call your doctor."
The original goal of the study was to assess the effects of aspirin and
sulotroban after angioplasty. However, results showed sulotroban therapy
to be less effective than aspirin. Researchers performed coronary angiograms
on study patients before and six months after angioplasty. They found the
angiograms looked the same. One-half of the patients receiving placebo developed
restenosis. The researchers found that neither aspirin nor sulotroban significantly
reduced restenosis.
"Because the recurrence rate after angioplasty is so high, prior studies
have generally focused on the angiograms," says Dr. Savage. "An
interesting feature of our study is that, although the angiograms looked
similar, the patients did much better when taking aspirin."
Other centers participating in the aspirin study are: University of Florida,
and Gainesville Veterans Administration Medical Center, Gainesville, Fl.;
South Miami Hospital, South Miami, Fl.; Florida Hospital, Orlando, Fl.;
University Hospital, Jacksonville, Fl.; Maritime Heart Hospital, Halifax,
Nova Scotia, Canada; Hospital of the University of Pennsylvania, Philadelphia,
Pa.; Temple University, Philadelphia, Pa.; West Hospital, Richmond, Va.