Long-term mortality after primary percutaneous coronary intervention for high-risk myocardial infarction.

Background: Primary percutaneous coronary intervention (PPCI) has evolved, including the introduction of stents and platelet glycoprotein IIb/IIIa receptor inhibitors (GPI). The effects of these changes and other variables on long-term survival for a single-centre service were studied.

Methods: A prospective database of clinical and angiographic variables were kept for patients treated with PPCI in Waikato Hospital from 1996 to 2006 (n=527). This was analysed with long-term mortality data. Survival was recorded using Kaplan-Meier curves. Multivariate analysis of factors at presentation, including ethnicity was performed.

Results: 5, 8 & 10-year survival rates were 76.5% (n=274), 72.7% (n=125) & 71.0% (n=19) respectively. Increased stent (42.8% vs. 84.1%, p<0.001) and GPI (39.6% vs. 73.3%, p<0.001) use was seen between early and late stages of the study. Stent use was associated with greater 5-year survival (80.5% vs. 70.8%, p=0.02), but GPI use was not. Multivariate analysis showed stent use independently predicted reduced mortality. Age, Maori ethnicity, renal failure and cardiogenic shock predicted higher mortality.

Conclusions: Survival after PPCI remains high long-term. Stent and GPI use significantly increased. Stent, but not GPI, use was associated with improved survival. Maori ethnicity was under-represented in the study and is associated with worse long-term outcomes after myocardial infarction (MI).