Background Randomised controlled trials have demonstrated improved outcomes with an early invasive strategy compared with routine care after fibrinolysis among patients with ST-elevation myocardial infarction. However, it remains uncertain whether specific patient subsets derive differential benefit from an early invasive strategy.

Methods Using patient-level data from seven randomised trials, we studied the relationship between treatment assignment (early invasive vs standard care) and adverse cardiovascular events. The outcomes assessed were death/reinfarction at 30 days and at 1 year, as well as death/reinfarction/recurrent ischaemia, major bleeding and stroke at 30 days. The analyses were conducted in strata (age, sex, diabetes, prior infarction, Killip class, anterior infarction and time from symptom onset to fibrinolysis) to assess for an interaction between the stratifying variable and treatment assigned.

Results There were 101 deaths and 115 recurrent infarctions at 30 days in 3010 patients. There were no strata where an invasive strategy conferred a differential treatment effect. With the exception of a marginally significant interaction between Killip class and treatment for death/reinfarction at 30 days and 1 year (p values for interaction 0.044 and 0.038, respectively), no interactions between the stratifying variables and treatment assignment were observed.

Conclusions Benefit from an early invasive strategy after fibrinolysis for ST-elevation myocardial infarction is similar across patient subgroups stratified by these clinical characteristics. Therefore, prediction of risk and benefit from an early invasive strategy after fibrinolysis for ST-elevation myocardial infarction is best achieved by global risk evaluation rather than specific patient characteristics.