Impact of previous percutaneous coronary intervention on angiographic and clinical outcomes in patients with ST-segment elevation myocardial infarction.

Background: The prognosis of patients with ST-segment elevation myocardial infarction (STEMI) and previous percutaneous coronary intervention (PCI) is uncertain.

Objective: To evaluate if previous PCI in patients with STEMI increases the risk of major cardiovascular events, and if final epicardial blood flow differs according to the reperfusion strategy.

Material and methods: Observational, longitudinal, comparative sub-study of the PHASE-MX trial that included patients with STEMI and reperfusion within 12 hours of symptom onset, who were classified according to their history of PCI. The occurrence of the composite primary endpoint (cardiovascular death, re-infarction, congestive heart failure and cardiogenic shock) within 30 days was evaluated using Kaplan-Meier estimates, log-rank test and Cox proportional hazards model. Epicardial blood flow was assessed using the TIMI grading system after reperfusion.

Results: A total of 935 patients were included; 85.6% were males and 6.9% had a history of PCI; 53% underwent pharmacoinvasive therapy, and 47%, primary PCI. The incidence of the composite primary endpoint at 30 days in patients with a history of PCI was 9.8% vs 13.3% in those with no previous PCI (p = 0.06). Among the patients with previous PCI, 87.1% reached a final TIMI grade 3 flow after primary PCI vs. 75% in the group with pharmacoinvasive strategy (p = 0.235).

Conclusions: A history of PCI does not increase the risk of major cardiovascular events at 30 days; however, it impacted negatively on the final angiographic blood flow of patients that received pharmacoinvasive therapy (compared to primary PCI).