Relation of pain-to-balloon time and myocardial infarct size in patients transferred for primary percutaneous coronary intervention.

The paradigm of a shorter pain-to-balloon time decreasing extent of infarct size may be not completely true in transferred patients. This study evaluated the influence of pain-to-balloon time on infarct size as assessed by delayed enhancement magnetic resonance imaging in patients transferred from a peripheral hospital to a tertiary center for primary coronary angioplasty (percutaneous coronary intervention [PCI]). Sixty patients (40 men, 64 +/- 3 years of age) with first acute myocardial infarction were treated within <168, 168 to 222, 223 to 300, and >300 minutes. A presentation score system including clinical, laboratory, and echocardiographic data was used to classify severity of presentation at admission. Magnetic resonance imaging was performed 6 +/- 3 days after PCI. Group 1 had a higher presentation score than did group 2 (p <0.02) and group 3 (p <0.02). Group 1 had a significantly longer delayed enhancement than did group 2 (p <0.002) and group 3 (p <0.03). In conclusion we found that patients with worse presentation are transferred sooner for primary PCI. This approach in these patients does not decrease infarct size likely because of unavoidable delay to reperfusion. This finding suggests a different therapeutic strategy in these patients.