Determination of risk factors associated with adverse outcomes of thrombolysis in acute ST Elevation Myocardial Infarction (STEMI)

ABSTRACT

Objective: Thrombolysis is the standard treatment for STEMI in most developing countries. However, adverse events attributable to thrombolysis occur, and must be considered in risk -benefit decisions. We aimed to estimate the local incidence of thrombolysis complications, whilst determining factors predisposing to adverse outcomes. Design and Methodology: A multicentre, prospective, observational cohort study was conducted; including consecutive adults with STEMI presenting to 3 Emergency Departments (EDs). Primary outcomes were complications and 30-day mortality. Results: 236 participants were enrolled (78.0% Indo- Trinidadian; 72.9% Male; 46.2% Hypertensive; 44.9% Diabetic; 57.9% Smokers). 27.5% of patients experienced complications; mainly a c u t e h e a r t f a i l u r e ( AHF) (8.5%) and cardiogenic shock (8.1%). In-hospital and 30-day mortality rates were 5.9 % and 9.2% respectively. Adverse outcomes of thrombolysis occurred in 9 (3.8%) patients (one intracerebral haemorrhage). No deaths were directly attributable to thrombolysis. No risk factor correlated with complications of thrombolysis, however a t r i o v e n t r i c u l a r ( AV) block (OR 9.73, CI 1.70 - 55.87, p = 0.011) and b l o o d u r e a n i t r o g e n ( BUN) (OR 1.09, CI 1.04 - 1.14, p < 0.001) were associated with increased in hospital mortality. Age ≥ 75 (OR 16.72, CI 1.45 - 192.44, p = 0.024), Systolic blood pressure (SBP) (OR 0.97, CI 0.96 - 0.99, p = 0.009) and BUN (adjusted OR 1.08, CI 1.03 - 1.13, p = 0.002) correlated with increased 30-day mortality. Conclusion: Thrombolysis for STEMI was associated with a low incidence of adverse events and similar mortality to developed nations. No factor was associated with adverse outcomes, although older age, high BUN, low SBP or AVB increased mortality risk. These findings can guide local physicians counselling patients/relatives regarding thrombolysis for STEMI.