Angiographic Estimation of Culprit Vessel Disease Severity in Acute ST- Segment Elevation Myocardial Infarction after Thrombolysis

INTRODUCTION: To study the angiographic disease severity of the infarct vessel after thrombolysis in patients with acute ST-elevation myocardial infarction and their 90 days outcome. METHODS: We conducted a retrospective analysis of a prospectively maintained cardiology database at Shifa International Hospital from February 2011 to August 2011. A total of 57 patients who underwent thrombolysis for acute ST elevated Myocardial Infarction and subsequent coronary angiographies within 24 hours of hospitalization were studied. Angiographic disease severity in the infarct vessel was quantified as mild (<50%), moderate (50-70%), severe (70-99%) and total occlusion (100%). Secondary outcomes of recurrent ischemia/reinfarction, target lesion revascularization and death were also assessed at three months follow up. RESULTS: Thrombolysis was successful in 48 patients. All nine cases of failed thrombolysis underwent rescue PCI. Mean time of catheterization from thrombolysis was 16±4 hours. Total 56 (98.2%) patients had severe (>70%) and 1 patient had moderate (50-70%) angiographic disease of the infarct vessel. Left anterior descending artery was the infarct vessel in 32 (56%) cases and right coronary artery in 20 (35%). Total 15 (26%) patients had double vessel and 11 (19%) had triple vessel coronary artery disease. Percutaneous coronary intervention was performed in all patients using bare metal stents or drug eluting stents. At three month follow-up, only one patient had recurrent myocardial infarction due to stent thrombosis. CONCLUSIONS: The overwhelming majority of patients presenting with ST elevation myocardial infarction have angiographic evidence of severe underlying disease in the infarct vessel despite clinically successful thrombolysis.