Context: Whether the superior results of percutaneous coronary intervention (PCI) reported in clinical trials in which patients with ST-segment elevation myocardial infarction (STEMI) received reperfusion treatment can be replicated in daily practice has been questioned, especially whether it is superior to prehospital thrombolysis (PHT).
Objective: To evaluate the outcome of different reperfusion strategies in consecutive STEMI patients.
Design, setting, and patients: A prospective observational cohort study of 26 205 consecutive STEMI patients in the Register of Information and Knowledge about Swedish Heart Intensive Care Admissions (RIKS-HIA) who received reperfusion therapy within 15 hours of symptom onset. The registry includes more than 95% of all Swedish patients, of all ages, who were treated in a coronary intensive care unit between 1999 and 2004.
Interventions: Seven thousand eighty-four patients underwent primary PCI; 3078, PHT; and 16 043, in-hospital thrombolysis (IHT).
Main outcome measures: Mortality, reinfarction, and readmissions as reported in the National Health Registries through December 31, 2005.
Results: After adjusting for younger age and less comorbidity, primary PCI was associated with lower mortality than IHT at 30 days (344 [4.9%] vs 1834 [11.4%]; hazard ratio [HR], 0.61; 95% confidence interval [CI], 0.53-0.71) and at 1 year (541 [7.6%] vs 2555 [15.9%]; HR, 0.68; 95% CI, 0.60-0.76). Also primary PCI correlated with lower mortality than PHT at 30 days (344 [4.9%] vs 234 [7.6%]; HR, 0.70; 95% CI, 0.58-0.85) and 1 year (541 [7.6%] vs 317 [10.3%]; HR, 0.81; 95% CI, 0.69-0.94). Prehospital thrombolysis predicted a lower mortality than IHT at 30 days (HR, 0.87; 95% CI, 0.76-1.01) and at 1 year (HR, 0.84; CI 0.74-0.95). Beyond 2 hours' treatment delay, the observed mortality reductions with PHT tended to decrease while the benefits with primary PCI seemed to remain regardless of time delay. Primary PCI was also associated with shorter hospital stay and less reinfarction than either PHT or IHT.
Conclusions: In unselected patients with STEMI, primary PCI, which compared favorably with IHT and PHT, was associated with reduced duration of hospital stay, readmission, reinfarction, and mortality.