Abstract 9608: Intracoronary Administration of Nicorandil During Direct Coronary Stenting Complements Restoration of Regional Perfusion at Subacute Phase of Myocardial Infarction: A Demonstration With O-15 Water Pet

Abstract

Purpose: Controversies exist regarding the impact of nicorandil as the adjunctive therapy for direct coronary stenting in patients with ST elevation myocardial infarction (STEMI).Therefore, we performed O-15 water positron emission tomography (water PET) to quantify regional myocardial perfusion in patients with STEMI who received nicorandil or no adjunctive therapy during successful direct stenting.

Methods:In 28 patients with STEMI (65+/-13 yrs: 22 males), direct stenting was performed within 8 hrs after the onset. Five of 28 patients who underwent successful direct stenting received intracoronary administration (i.c.) of nicorandil 4 mg immediately after the first recanalization of culprit lesion.At 3 to 4 weeks from the onset, water PET was performed in which myocardial blood flow (MBF) was measured at rest and during hyperemia and myocardial vascular esistance (MVR) was calculated. Data were obtained from both reperfused and normal control regions in each patient.

Results: See Figure. In patients who did not receive nicorandil (No-Nico), MBF in reperfused area (Rep) was lower than that in normal control regions (Cont) both at rest and during hyperemia (ATP). However, in the nicorandil-treated patients, MBF in Rep was restored to the similar level of that in Cont both at rest and during ATP. MVR was elevated in Rep both at rest and during ATP in No-Nico patients; such elevation of MVR in Rep was successfully prevented in the nicorandil-treated patients.

Conclusion: O-15 water-PET at subacute phase revealed that i.c.nicorandil during direct stenting successfully prevented the elevation of myocardial vascular resistance and thus, restored myocardial blood flow in reperfused areas to the similar level as that in non-infarcted regions in patients with STEMI.