New data published in NEJM demonstrates that patients with STEMI who cannot undergo primary PCI within 60 minutes of first medical contact have similar clinical outcomes with early fibrinolysis with Metalyse® (tenecteplase, TNK-tPA) in combination with clopidogrel and enoxaparin, followed by timely angiography (pharmaco-invasive strategy), compared to patients given primary PCI after the 60-minute window.(1)
"In STEMI patients, the most important thing is to re-establish blood supply to the heart. Whilst the preferred option is primary PCI, the best strategy for reperfusion in patients who do not have access to timely PCI has been unclear. The STREAM study was set up to help answer this question" explained Co-principal STREAM(a) Investigator, Professor A. Gershlick, University of Leicester. "The results from STREAM confirm that patients who receive early fibrinolytic treatment followed by rescue angipoplasty or in-hospital angiography have a similar 30-day outcome to those receiving primary PCI, providing a therapeutic option for those patients who cannot receive primary PCI within guideline mandated times - for example because of geographical location or access to specialist centres."
In STREAM, the primary composite endpoint of death, cardiogenic shock, congestive heart failure and reinfarction within 30 days was observed in 116 of 939 patients (12.4%) that received fibrinolysis, compared to 135 of 943 patients (14.3%) who received early primary PCI (relative risk in the fibrinolysis group 0.86 (0.68 - 1.09) p=0.21).(1)
Rates of fibrinolytic therapy use are falling in the UK, reflecting improvements in access to specialist Heart Attack Centres.2 In England in 2011/2012, 95% of patients who received any reperfusion treatment received primary PCI compared with 82% in 2010/11. In Wales the increase was from 30% to 50%. However, in some areas PCI rates are still significantly lower than national averages.(2) This is particularly true in hospitals with large rural catchment areas.
"The NHS has done extremely well in providing access to timely PCI for most patients in the UK; however, delays are still present in some areas due to geography and siting of Heart Attack Centres. Even in places with generally good access to PCI, traffic problems or adverse weather conditions can cause short-term issues with providing intervention within the recommended time frame" said Dr Chris Moulton, Consultant in Emergency Medicine, Royal Bolton Hospital. "This trial has important implications for the UK, especially if real-world outcomes bear out the study findings that a strategy based on early fibrinolysis is associated with comparable outcomes to waiting for primary PCI. Overall, this is a very interesting and exciting development in the field of reperfusion therapy for STEMI."
According to Prof Tom Quinn, Associate Dean for Health and Medical Strategy, University of Surrey and member of the STREAM Trial Steering Committee, the study results provide an opportunity to build on paramedics' experience of giving pre-hospital thrombolysis, to ensure that patients who cannot reach a heart attack centre within the target time benefit from the pharmaco-invasive approach.