Rescue percutaneous coronary intervention in the pharmaco-invasive era of ST-elevation myocardial infarction: insights from the STREAM-2 trial

Contemporary guidelines support the use of a pharmaco-invasive (PI) strategy with immediate transfer to a percutaneous coronary intervention (PCI)-capable hospital for ST-elevation myocardial infarction when a timely primary PCI (pPCI) is unattainable. However, when reperfusion with fibrinolysis fails to occur, rescue PCI is recommended.

In a pre-specified analysis from STREAM-2, we explored patients randomized to PI treatment and compared those receiving half-dose tenecteplase and required rescue intervention to those with successful fibrinolysis undergoing scheduled angiography. To provide context for those randomized to pPCI, we also explored the relationship between sites of randomization, i.e. community hospital (CH) vs. ambulance on clinical outcomes. Resolution of ST-elevation following angiography and the composite of 30-day all-cause death, shock, heart failure, and reinfarction, as well as safety, reflected by stroke and non-intracranial bleeding, were measured. Of the 583 patients in the current study, 168 patients required rescue intervention (43.5%), 218 patients had successful fibrinolysis scheduled for angiography, and 197 were randomized to pPCI. Rescue PCI patients, compared with those undergoing scheduled angiography, had less ST resolution ≥50% (76.3 vs. 92.5%, P < 0.001) and worse clinical composite outcomes at 30 days (16.7 vs. 6.0%, P < 0.001) with a higher risk of intracranial haemorrhage (2.4 vs. 0.5%). Intermediate outcomes were observed for patients undergoing pPCI (ST resolution ≥50%: 78.7%; a 30-day composite outcome: 12.2%). Rescue intervention deployed in CH patients required 10 min longer compared with ambulance patients; however, there was a similar ST resolution of ≥50% (72.2 vs. 80.5%, P = 0.219) and comparable 30-day composite outcomes [17.6 vs. 15.7%, relative risk (RR) 0.97, 95% confidence interval (CI) 0.50–1.87], irrespective of location. Primary PCI required 48 min longer in CH patients, but resulted in similar outcomes to ambulance patients (ST resolution ≥50%: 77.0 vs. 80.2%, P = 0.595; 30-day composite outcome: 9.3 vs. 15.6%, RR 1.57, 95% CI 0.72–3.41, respectively).

Contemporary PI with half-dose tenecteplase in older patients requiring rescue intervention led to less ST resolution and worse 30-day outcomes compared with those with successful fibrinolysis receiving scheduled angiography. Notably, delays to deploying rescue PCI in CH patients were shortened over those previously achieved thereby resulting in similar outcomes to those randomized in the ambulance. Our results reinforce the benefits of functional hub and spoke models with rapid transfer to a PCI-capable facility.