Relationship between community hospital versus pre-hospital location of randomisation and clinical outcomes in ST-elevation myocardial infarction patients: insights from the Stream study

• Published in: European heart journal. Acute cardiovascular care 2018-09, Vol.7 (6), p.504-513
• Main Authors: Welsh, Robert C, Goldstein, Patrick, Sinnaeve, Peter, Ostojic, Miodrag C, Zheng, Yinggan, Danays, Thierry, Westerhout, Cynthia M, Van de Werf, Frans, Armstrong, Paul W
• Format: Article
• Language: English
• ISSN: 2048-8726; 2048-8734
• DOI: 10.1177/2048872617700872

Aims: The STREAM study randomly assigned ST-elevation myocardial infarction (STEMI) patients to receive a pharmacoinvasive versus primary percutaneous coronary intervention reperfusion strategy. We assessed whether there was an association between outcomes based on randomisation at a community hospital versus a prehospital location. Methods/results: Community hospital patients (358/1866 (19.2%)) were compared to prehospital patients and their outcomes categorised into pharmacoinvasive according to their treatment assignment. Compared to prehospital patients, community hospital patients had more diabetes (17.8% vs. 11.5%, P=0.001), higher Killip Class >1 (9.4% vs. 5.0%, P=0.002) and thrombolysis in myocardial infarction risk scores ⩾5 (18.2% vs. 12.4%, P=0.005). The 30-day primary endpoint (death, shock, congestive heart failure and re-infarction) for community hospital patients was 14.9% versus 13.2% for prehospital patients (P=0.403). Community hospital pharmacoinvasive patients tended to receive less rescue (35.1% vs. 42.8%, P=0.062); when deployed their rescue was delayed 43 minutes. Community hospital patients undergoing primary percutaneous coronary intervention experienced a delay of 31 minutes versus prehospital patients. Pharmacoinvasive patients receiving scheduled angiography from a community hospital and prehospital patients had comparable times to angiography (17.7 vs. 18.7 hours) and low event rates (6.2% vs. 8.0%). Although the interaction between randomisation location and treatment received on the primary endpoint was not significant (Pinteraction=0.065) those pharmacoinvasive patients requiring rescue from community hospitals had worse outcomes than prehospital rescue patients (odds ratio 2.28, 95% confidence interval 1.16–4.49). Conclusion: Within STREAM, STEMI patients randomly assigned at community hospitals had a higher baseline risk but similar outcomes compared to those studied prehospital patients irrespective of successful pharmacoinvasive therapy or primary percutaneous coronary intervention. However, worse outcomes in the pharmacoinvasive patients requiring rescue in community hospitals emphasises their need for immediate transfer to a percutaneous coronary intervention-capable hospital.