Cardiology · 2003
Primary PCI versus thrombolysis for acute STEMI (Keeley meta-analysis of 23 trials)
PAMI = Primary Angioplasty in Myocardial Infarction
Through the 1980s and 1990s, thrombolytic therapy with agents like streptokinase and tissue plasminogen activator had transformed the care of acute STEMI, reducing mortality and limiting infarct size compared with conservative management. Primary percutaneous coronary intervention, opening the culprit artery mechanically, was available at catheterization-capable hospitals but required equipment, staffing, and activation infrastructure that most centers did not have around the clock. Individual trials comparing the two strategies had shown trends favoring PCI, but most were too small to demonstrate a mortality benefit with confidence, and no single trial settled the question.
Elizabeth Keeley at the University of Florida, working with Judith Boura and William O'Neill of William Beaumont Hospital, pooled individual data from 23 randomized trials that had compared primary PCI against any thrombolytic regimen in 7,739 STEMI patients. The meta-analysis, published in the Lancet in early 2003, found short-term mortality of 7% with PCI versus 9% with thrombolytics. Non-fatal reinfarction occurred in 3% of PCI patients compared with 7% of the thrombolytic group; stroke in 1% versus 2%. The mechanical advantage was consistent regardless of which thrombolytic agent served as comparator.
The pooled sample size gave the analysis statistical power that no individual trial could match, and the consistency across different thrombolytic comparators answered the objection that the control arm varied. The study also included sensitivity analyses restricting to trials with short transfer times, which bore directly on the practical question of whether the benefit held even when PCI required some delay beyond first medical contact.
National and international cardiology societies used the Keeley analysis as the primary evidence base for guideline revisions that made primary PCI the preferred reperfusion strategy for STEMI wherever it could be delivered within an acceptable time window. Door-to-balloon time emerged as a quality metric measured at every hospital performing primary PCI; the 90-minute target embedded in ACC/AHA guidelines traced directly to the trial evidence Keeley synthesized. Regional transfer protocols developed to move STEMI patients from non-PCI hospitals to catheterization centers became standard in most developed health systems.
The infrastructure consequences extended beyond individual hospitals. States and regions built spoke-and-hub networks with direct-transfer agreements, pre-hospital ECG programs, and cath lab activation by emergency medical services before patient arrival. The 2003 meta-analysis did not create primary PCI, but it produced the consolidated evidence that converted isolated trial results into a system-level reorganization of emergency cardiac care.
Key People
- Elizabeth Keeley — University of Florida; first author of the definitive meta-analysis
- Judith Boura — Co-author; statistical analysis
- William O'Neill — Co-author; interventional cardiology, William Beaumont Hospital
Lancet, 2003
Related landmarks
- 2002 · Heart Protection Study (HPS) (Cardiology)
- 2000 · HOPE (Heart Outcomes Prevention Evaluation) (Cardiology)
- 2009 · RE-LY (Dabigatran versus warfarin in atrial fibrillation) (Cardiology)
- 1995 · WOSCOPS (West of Scotland Coronary Prevention Study) (Cardiology)