This study sought to evaluate, in a prospective and randomized trial, the relative
efficacies of three possible therapeutic strategies for patients with a single severe
proximal stenosis of the left anterior descending coronary artery and stable angina.
Although percutaneous transluminal coronary angioplasty and coronary artery bypass
surgery are often performed in patients with a single proximal stenosis of the left
anterior descending coronary artery, it is unclear whether revascularization offers
greater clinical benefit than medical therapy alone.
At a single center, 214 patients with stable angina, normal ventricular function and
a proximal stenosis of the left anterior descending coronary artery > 80% were randomly
assigned to undergo mammary bypass surgery (n = 70), balloon angioplasty (n = 72)
or medical therapy alone (n = 72). Angioplasty had to be considered technically feasible
in every case. The predefined primary study end point was the combined incidence of
cardiac death, myocardial infarction or refractory angina requiring revascularization.
At an average follow-up period of 3 years, a primary end point had occurred in only
2 patients (3%) assigned to bypass surgery compared with 17 assigned to angioplasty
(24%) and 12 assigned to medical therapy (17%) (p = 0.0002, angioplasty vs. bypass
surgery; p = 0.006, bypass surgery vs. medical treatment; p = 0.28, angioplasty vs.
medical treatment, all by log-rank test). There was no difference in mortality or
infarction rates among the groups. However, no patient allocated to bypass surgery
needed revascularization, compared with eight and seven patients assigned, respectively,
to coronary angioplasty and medical treatment (p = 0.019). Both revascularization
techniques resulted in greater symptomatic relief and a lower incidence of ischemia
on the treadmill test; however, all three strategies eventually resulted in the abolition
of limiting angina.
The more aggressive therapeutic approach with initial bypass surgery for patients
with a single severe proximal stenosis of the left anterior descending coronary artery
is associated with a lower incidence of medium-term adverse events than coronary angioplasty
or medical treatment. However, all three strategies resulted in a similar incidence
of death and infarction during an average follow-up period of 3 years. This information
should be taken into consideration when physicians and patients make therapeutic choices
in this setting.