Background: Women with non-ST elevation myocardial infarction (NSTEMI) have similar extent of myocardial ischemia but less obstructive coronary artery disease (CAD) than their male counterparts. We tested the impact of global coronary artery plaque area and artery tortuosity on myocardial perfusion in NSTEMI patients.
Methods: Coronary artery plaque area was determined by quantitative angiography in 108 patients (32% women) with NSTEMI. Myocardial perfusion was assessed by contrast echocardiography in the 17 individual left ventricular segments. Artery tortuosity was defined as ≥3 curves >45° in a main coronary artery.
Results: Age, prevalence of hypertension, and diabetes did not differ between sexes (all nonsignificant). Women had lower prevalence of ≥50% coronary artery stenosis (74% vs. 91%, p<0.05), while global coronary plaque area (35±22 vs. 43±21mm(2)) and the number of segments with hypoperfusion (6.9±3.7 vs. 7.2±3.4) did not differ between sexes (both p>0.07). In multivariate analysis, larger coronary artery plaque area was associated with a 35% higher risk for having severe myocardial hypoperfusion (odds ratio 1.35 [95% confidence interval 1.01-1.80], p<0.05) in the total study population, while no association between artery tortuosity and myocardial ischemia was found. Similar results were obtained in separate analysis among women and men.
Conclusion: In women and men with NSTEMI, the global coronary artery plaque area was an important determinant of the severity of myocardial hypoperfusion at rest independent of presence of significant coronary stenoses. These findings may expand current understanding of NSTEMI in patients with nonobstructive CAD.
Trial registration: ClinicalTrials.gov NCT01122069.