NEW YORK (Reuters Health) – Compared with fibrinolytic therapy, primary percutaneous coronary intervention (PCI) in patients with acute MI is associated with a significant reduction in early mortality, with patients at highest risk gaining the greatest absolute benefit, an international team reports based on the results of a meta-analysis of 22 randomized trials.

Conversely, the investigators note in the American Heart Journal for March, timely fibrinolytic therapy remains a valid approach for low-risk patients because they derive relatively little advantage from primary PCI.

Dr. Eric Boersma, with Erasmus Medical Center, Rotterdam, The Netherlands, and colleagues conducted the meta-analysis to determine “which categories of patients with myocardial infarction would benefit most from the strategy of primary PCI and, thus, have lowest numbers needed to treat to prevent a death.”

The pooled data covered outcomes of 6763 patients randomized to primary PCI or fibrinolytic therapy. The patients were classified into mortality risk quartiles based on a risk score developed and validated by the researchers.

Overall mortality within 30 days was 6.6%, being lower in patients randomized to primary PCI (5.3%) than in those assigned to fibrinolysis (7.9%; p<0.001), according to the report. The relative reduction in mortality was similar across all risk quartiles, the authors found. The absolute risk reduction, however, strongly correlated with risk category. Specifically, “the numbers needed to treat to prevent a death by primary PCI versus fibrinolysis was 516 in the lowest quartile of estimated risk compared with only 17 in the highest quartile,” Dr. Boersma and colleagues report. They conclude that primary PCI should therefore be the first choice for reperfusion of MI patients whenever feasible. The team adds: “If access to PCI is longer than 2 hours, fibrinolysis remains a legitimate option, especially for patients with a low-risk score due to the small absolute risk difference between both treatment modalities in this patient group. Therefore, in regions where hospitals with PCI facilities are rare (or) where geography does not allow primary PCI in all patients with MI, this risk score might be used to select those higher risk patients who benefit most from primary PCI.” Reference:
High-risk patients with ST-elevation myocardial infarction derive greatest absolute benefit from primary percutaneous coronary intervention: Results from the Primary Coronary Angioplasty Trialist versus Thrombolysis (PCAT)-2 Collaboration

Am Heart J 2011;161:500-507.e1