Frequency and distribution of angiographically occluded coronary artery and in-hospital outcome of patients with Non ST elevation myocardial infarction.

Objective: To calculate the frequency and distribution of occluded coronary artery in patients with recent non-ST elevation myocardial infarction undergoing coronary angiography, and to compare major adverse cardiovascular events during hospitalisation with patients suffering from non-occluded coronary artery.

Methods: The cross-sectional analytical study was conducted at Tabba Heart Institute, Karachi, from July2013 to March 2014. Patients of both gender and all ages undergoing angiography with non-ST elevation myocardial infarction were included. Data on patient demographics, angiographic findings and in-hospital complications was collected. Frequency of occluded vessels and their distribution was reported. Multivariate logistic regression modelling was used to examine variables associated with an occluded coronary artery in non-ST elevation myocardial infarction. Major adverse cardiovascular events were compared between patients of occluded and non-occluded coronary aetery. A two sided p-value of < 0.05 was taken as significant.

Results: In 703 patients studied, occluded coronary artery was present in 277(39%). Predictors of having an occluded coronary artery were increasing age (57.6±11.2 vs. 60.0±10.0; p: 0.03) and low left ventricular ejection fraction (43.9±12.2 vs. 50.1±10.1; p: 0.000). There was no significant difference in terms of major adverse cardiovascular events in patients with occluded and non-occluded coronary arteries (Hazard Ratio: 0.53, 95% confidence interval: 0.14-1.98; p=0.33).

Conclusions: Totally occluded coronary vessel is a frequent finding in non-ST elevation myocardial infarction, highlighting the need for angiography and re-vascularisation to salvage at-risk myocardium in selected patients.