Background: The efficacy of a routine invasive strategy early after fibrinolysis in relation to baseline risk status is unclear. We sought to characterize the interaction between patient risk and treatment with routine invasive strategy early after fibrinolysis for ST-segment elevation myocardial infarction.
Methods: We pooled 2,974 patients from 7 randomized trials of fibrinolysis-treated patients with ST-segment elevation myocardial infarction comparing a routine early invasive strategy with a standard approach of percutaneous coronary intervention (PCI) guided by recurrent ischemia or need for rescue. Cox proportional hazards regression was used to examine the interaction between baseline patient risk classified by Thrombolysis in Myocardial Infarction risk score (low/intermediate: ≤ 5 [n = 2,697] vs high: > 5 [n = 277]) and treatment with routine early invasive strategy.
Results: Time to PCI after fibrinolysis was longer among patients randomized to standard treatment compared with routine early invasive strategy in the low/intermediate-risk strata (median 11.4 vs 3.5 hours), but was only marginally different between the 2 groups in the high-risk strata (median 4.1 vs 3.5 hours). There was a significant interaction between treatment assignment and risk status for the composite of 30-day death or reinfarction (P = .01). Compared with standard treatment, routine early invasive strategy was associated with lower 30-day death/reinfarction in the low/intermediate-risk stratum (7.5% vs 4.0%, P < .001), but not in the high-risk stratum (14.9% vs 19.6%, P = .45).
Conclusions: Although clearly beneficial among the larger subgroup of patients at low/intermediate risk, the benefit of a routine early invasive strategy was not evident in the smaller subgroup of higher-risk patients in the context of an increased requirement for urgent PCI in the comparative standard treatment arm.
Copyright © 2014 Elsevier Inc. All rights reserved.