According to this study:
* Invasive treatment for NSTE ACS is beneficial in both men and women with elevated cardiac biomarkers.
* However, invasive treatment for NSTE ACS appears to have no benefit in women without elevated cardiac biomarkers and may even be harmful.
An invasive treatment approach is often used in patients with non-ST-segment elevation acute coronary syndrome (NSTE ACS), but its benefits in women are unclear. To determine whether an invasive or a conservative treatment plan is preferable in both women and men with NSTE ACS, O'Donoghue and colleagues searched for trials comparing these treatment strategies in NSTE ACS patients between 1970 and April 2008. Eight randomized trials were selected for the metaanalysis.
Invasive treatment was defined as coronary angiography (with revascularization, if appropriate). Conservative treatment included any combination of drug therapies with the use of angiography limited to patients with recurrent symptoms. The primary outcome evaluated over the 12 months of follow-up was death, nonfatal myocardial infarction, or rehospitalization for ACS.
A total of 10,150 patients were studied: 3,075 women (mean age, 64.1) and 7,075 men (mean age, 61.3). Women were more likely to have comorbidities such as hypertension, diabetes, or hyperlipidemia. Men were more likely to smoke cigarettes and to have a history of myocardial infarction. At randomization, more men than women had elevated cardiac biomarkers. The incidence of the primary outcome was 23% (709 out of 3,075) in women and 24% (1,679 out of 7,075) in men.
The findings reveal a relative benefit of invasive treatment (a significant decrease in the primary outcome of about one-third) in both men and women with elevated cardiac biomarkers. However, invasive treatment appears to have no benefit in women without elevated cardiac biomarkers and may even be deleterious. The authors link these findings to the fact that, in a significant proportion of women, angiography showed no coronary artery disease despite the presence of ischemic symptoms and elevated enzymes. Therefore, a conservative treatment strategy may be preferable in low-risk women with NSTE ACS.
The authors suggest the possibility that a different mechanism of vascular disease, a higher incidence of coronary vasospasm or another acute state, may mimic ACS in some women.
CC