Long-term survival benefits of thrombolysis: the Royal College of General Practitioners' myocardial infarction study

OBJECTIVE: To investigate whether there is a long-term survival benefit from receipt of thrombolysis in routine care particularly pre-hospital thrombolysis, using 20 year mortality data from the RCGP myocardial infarction (MI) cohort study. METHODS: During 1991-92 the RCGP MI study assessed GP delivery of thrombolysis. Participants who received pre-hospital thrombolysis (n = 290), thrombolysis in hospital (n = 781) or no thrombolysis (n = 2021) were followed and mortality data collected to June 2012. The relationship between thrombolysis and survival time was analysed using Cox regression at 28 days, 1, 5, 10, 15 years post-AMI, and at end of follow-up (~20 years post-AMI). RESULTS: Compared to those who did not receive it, participants who received thrombolysis had a significant survival benefit at 28 days [adjusted hazard ratio (HR) 0.72, 95% confidence interval (CI): 0.58-0.90]; 1 year (adjusted HR 0.69, 95% CI: 0.57-0.83); 5 years (adjusted HR 0.76, 95% CI: 0.66-0.86); 10 years (adjusted HR 0.85, 95% CI: 0.77-0.95) and 15 years (adjusted HR 0.88, 95% CI: 0.80-0.96) post-AMI until end of follow-up (adjusted HR 0.92, 95% CI: 0.84-1.00). Pre versus in-hospital thrombolysis did not appear beneficial, although there was evidence among the pre-hospital group that short symptom onset-to-needle times conferred greater benefit. CONCLUSIONS: We found substantial long-term survival benefits associated with thrombolysis when used in routine care. Although primary percutaneous coronary intervention (pPCI) is now the choice treatment, thrombolysis remains an important option when pPCI cannot be delivered within 120 minutes of diagnosis.