STREAM: success for fibrinolysis before transport for PCI

Fibrinolysis with tenecteplase and contemporary antithrombotic therapy given before transport to a hospital capable of percutaneous coronary intervention (PCI) is as effective as primary PCI in ST-elevation myocardial infarction (STEMI) patients presenting within three hours of symptom onset, according to the results of the STREAM (Strategic Reperfusion Early After Myocardial Infarction) trial.

Lead investigator, Dr Frans Van de Werf (University of Leuven, Belgium) said: “Fibrinolysis before transfer is at least as effective as PCI, and an urgent catheterisation was avoided in two-thirds of patients. This gives clinicians time to consider other options, such as coronary artery bypass graft (CABG) surgery and medical therapy.”

STREAM differs from other trials investigating fibrinolysis before transfer for PCI in that patients were only given urgent PCI on arrival at the tertiary hospital if they had not reperfused (as judged by the ECG).
Because of this, the majority of patients avoided having to undergo PCI with fibrinolysis on board which has been associated with adverse outcomes in previous studies.

Discussing the study, which was published online in the New England Journal of Medicine (http://dx.doi.org/10.1056/NEJMoa1301092) to coincide with the presentation, Dr Freek Verheugt (Nijmegen University, the Netherlands) said: ” I think this will change practice in certain parts of the world where there are long driving times to PCI hospitals.”

The trial involved 1,915 STEMI patients from 15 countries who were first seen in community hospitals or by emergency medical personnel, and for whom there was going to be a delay of over one hour before PCI could be performed.
Before transfer, patients were randomised to PCI immediately after arrival or to tenecteplase plus enoxaparin, clopidogrel, and aspirin before arrival. Elderly patients had lower doses of clopidogrel (no loading dose) and enoxaparin.

When patients on tenecteplase reached a major medical centre, 36% needed urgent PCI.
The other 64% of patients did not need urgent PCI and received an angiogram an average of 17 hours after arrival and, based on the results, received PCI or CABG under non-urgent circumstances.

Table 1. STREAM: primary endpoint

The primary end point
– a composite of all-cause mortality, shock, congestive heart failure, and subsequent heart attack at 30 days – were similar between the immediate-PCI and tenecteplase groups.

Table 2. STREAM: ICH data

There was a significant increase in intracranial haemorrhage (ICH) in the fibrinolysis group, which led to the dose of tenecteplase being halved in people aged 75 years and older fairly early on in the course of the trial, after which the intracranial haemorrhage rate in the fibrinolysis group was reduced to 0.5% – not significantly different from the PCI group .
After the dosage amendment was made in the elderly, the primary end point almost reached significance in favor of the fibrinolysis group, Dr Van de Werf noted.

G Mohan