[Primary PCI in ST-elevation myocardial infarction: mode of referral and time to PCI]

Abstract

Introduction: According to the current guidelines for treatment of ST-elevation myocardial infarction (STEMI), percutaneous coronary intervention (PCI) should be performed within 90 min of first medical contact and total ischemic time should not exceed 120 min. The aim of this study was to analyze compliance with STEMI guidelines in a tertiary PCI center.

Methods: This was a prospective single-center registry of 223 consecutive STEMI patients referred for primary PCI between 2003 and 2007.

Results: In this population (mean age 60±12 years, 76% male), median total ischemic time was 4h 30 min (<120 min in 4% of patients). The interval with the best performance was first medical contact to first ECG (median 8 min, <10 min in 59% of patients). The worst intervals were symptom onset to first medical contact (median 104 min, <30 min in 6%) and first ECG to PCI (median 140 min, <90 min in 16%). Shorter total ischemic time was associated with better post-PCI TIMI flow, TIMI frame count and ST-segment resolution (p<0.03). The three most common patient origins were two nearby hospitals (A and B) and the pre-hospital emergency system. The pre-hospital group had shorter total ischemic time than patients from hospitals A or B (2h 45 min vs. 4h 44 min and 6h 40 min, respectively, p<0.05), with shorter door-to-balloon time (89 min vs. 147 min and 146 min, respectively, p<0.05).

Conclusions: In this population, only a small proportion of patients with acute myocardial infarction underwent primary PCI within the recommended time. Patients referred through the pre-hospital emergency system, although a minority, had the best results in terms of early treatment. Compliance with the guidelines translates into better myocardial perfusion achieved through primary PCI.