Men and women with acute coronary syndrome had similar declines in the incidence of death, myocardial infarction, and rehospitalization within six months when they were treated with an early invasive strategy including heart catheterization within 4 to 48 hours, according to an article in the December 25th issue of The Journal of the American Medical Association (JAMA).

Previous studies have shown conflicting results in outcome based on treatment strategy. One study showed that women had worse outcomes with invasive procedures, but women demonstrated improved outcomes in an observational study. The current study differed from previous studies in that it used a more contemporary management strategy including a potent platelet inhibitor in all patients and high utilization of stents during angioplasty.

Ruchira Glaser, M.D., and colleagues looked at the clinical characteristics and outcomes in men and women with acute coronary syndrome who were randomized to early angiography (heart catheterization) or no early angiography. The patients were participants in the TACTICS-TIMI 18 trial, conducted from December 1997 to December 1999 in 169 centers in North America and Europe.

The 2,220 patients (757 women and 1,463 men) were assigned to early invasive treatment (1,114, angiography and revascularization when appropriate) or conservative treatment (1,106). The latter approach included angiography and appropriate revascularization only if patients met specified criteria such as a positive stress test or recurrent ischemia. Patients were followed up at one and six months.

All patients received aspirin, intravenous heparin, and tirofiban for 48 hours or until revascularization. Tirofiban was given for at least 12 hours after percutaneous coronary revascularization.

At six months, men and women treated with the early invasive strategy had a similarly reduced rate (men, 36 percent; women, 28 percent) of the primary end points (death, myocardial infarction or rehospitalization) compared with patients treated with the conservative strategy. Benefits for both men and women were more marked if the patients had high-risk characteristics including a blood test before enrollment that demonstrated myocardial damage (men, 47 percent; women, 44 percent).

The researchers found that the women enrolled in the study were older and more frequently had hypertension. Women were less likely to have had a previous infarction or prior coronary artery bypass graft surgery. Angiography and intervention rates between men and women were similar, but women had less severe coronary artery disease.

The authors wrote that despite differences in characteristics of men and women with unstable angina, "these differences do not translate into significant differences in major outcomes between women and men who both benefit from a contemporary management strategy for ACS incorporating early invasive treatment ..."

The authors concluded that "... the choice of an invasive versus conservative strategy for acute coronary syndrome should be based on objective risk stratification measures, and not be influenced by the sex of patients."