Pre-hospital thrombolysis in ST-segment elevation myocardial infarction: a regional Australian experience

We thank French and colleagues for their letter on our article.1 As mentioned, the first medical contact (FMC) to device time in the primary percutaneous coronary intervention (PCI) arm of our registry1 was significantly longer than the guideline-recommended time of 90 minutes.2 Patients who had any contraindication to thrombolysis underwent primary PCI, irrespective of the travel time from FMC to the cardiac catheterisation laboratory (CCL). Therefore, there will always be patients with longer travel times if they are ineligible for pre-hospital thrombolysis, which will inevitably prolong the average transport time. Moreover, in our protocol, patients are transferred for primary PCI if the estimated FMC-to-CCL travel time is < 60 minutes — these travel times are estimated by the paramedics. At times, factors such as weather conditions or traffic congestion, and clinical reasons, including resuscitation from cardiac arrest and treatment of arrhythmias, may interfere with the transport and result in prolonged travel time. We agree that pre-hospital thrombolysis is a well established alternative for patients with long delays to primary PCI and is supported both by real world and randomised data.3-5 The decision whether to administer pre-hospital thrombolysis or transfer for primary PCI in patients with moderate delays to the CCL is a difficult one, and will be studied for older patients in the upcoming Strategic Reperfusion in Elderly Patients Early After Myocardial Infarction (STREAM-2) trial (http://clinicaltrials.gov/ct2/show/NCT02777580). We agree with French and colleagues that more patients should be considered for pre-hospital thrombolysis if long delays are expected.