Risk factors for acute non-ST-segment elevation myocardial infarction in a population sample of predominantly African American patients with chest pain and normal coronary arteries.

Background: We sought to investigate the relationship between echocardiographic left ventricular hypertrophy (LVH) and acute non-ST-elevation segment myocardial infarction (NSTE-MI) in patients with chest pain and angiographically normal coronary arteries.

Methods: Retrospective analysis of patients admitted for acute chest pain in a large urban hospital serving predominantly African American patients.

Results: 131 (of 700) patients had normal coronary arteries or only minimal luminal irregularities (ie, <10% luminal narrowing) on cardiac angiography and available cardiac biomarker data to define the presence or absence of MI. Mean age was 53 +/- 10 years, 76% were African Americans, 88% had a history of hypertension (49% uncontrolled) and 74% had LVH by echocardiography. Of these 131 patients, 22 (17%) had an acute NSTE-MI by creatine kinase MB criteria. The mean systolic blood pressure (BP) was significantly higher in patients with NSTE-MI compared with non-NSTE-MI group (156 +/- 30 vs 143 +/- 25 mm Hg, P=.04). Patients with NSTE-MI were more likely to have LVH (95% vs 70%, P=.03). NSTE-MI was present in 22% of patients with LVH compared with 3% without LVH (P=.02). The in-hospital course of NSTE-MI patients with LVH was not benign: 19% had persistent angina and positive stress thallium suggestive of recurrent myocardial ischemia and 48% had congestive heart failure. The results of multivariable model after adjusting for selected variables revealed that these two preexisting conditions were independently associated with NSTE-MI: LVH (OR=4.0, CI 1.06-10.05) and elevated systolic BP (OR=3.7, CI 1.01-10.64).

Conclusion: These findings provide preliminary evidence that LVH and uncontrolled hypertension predispose to NSTE-MI in this patient group.