Determinants and outcomes of coronary angiography after non-ST-segment elevation myocardial infarction. A cohort study of the Myocardial Ischaemia National Audit Project (MINAP).

OBJECTIVE

To investigate determinants of, and outcomes from, coronary angiography and intervention in patients with non-ST-segment elevation myocardial infarction (NSTEMI).

DESIGN

Observational study.

SETTING

44 British hospitals with interventional facilities.

PATIENTS

13,489 admissions with NSTEMI; July 2005 to December 2006.

MAIN OUTCOME MEASURES

Rate of angiography during index admission; death and readmission to hospital within 180 days.

RESULTS

Significantly lower rates of angiography were seen for women, the elderly, the most deprived and those having cardiac, and most non-cardiac, comorbidities. Performance of angiography, compared with no angiography, was not associated with lower rate of readmission (multiple adjusted hazard ratio (HR) = 0.96, 95% CI 0.74 to 1.24) unless accompanied by coronary intervention (HR = 0.73, 95% CI 0.56 to 0.95). Angiography was associated with reduction in 180-day mortality for survivors of hospitalisation (HR = 0.59, 95% CI 0.49 to 0.72); with greater reduction when followed by an intervention (HR = 0.34, 95% CI 0.28 to 0.42). This mortality benefit after intervention was seen both in women (HR = 0.42, 95% CI 0.29 to 0.60) and men (HR = 0.31, 95% CI 0.24 to 0.41), and across age groups: <65 years (HR = 0.25, 95% CI 0.14 to 0.44), 65-79 years (HR = 0.29, 95% CI 0.22 to 0.39) and > or =80 years (HR = 0.52, 95% CI 0.37 to 0.74). Mortality benefit was not significantly attenuated by the presence of comorbidities.

CONCLUSION

Performance of angiography and coronary intervention after NSTEMI was associated with mortality benefit that persisted in the presence of both cardiac and non-cardiac comorbidities. Mortality benefit was seen across age groups and was similar for both sexes.