TY - JOUR
T1 - Early metoprolol administration before coronary reperfusion results in increased myocardial salvage
T2 - Analysis of ischemic myocardium at risk using cardiac magnetic resonance
AU - Ibanez, Borja
AU - Prat-González, Susanna
AU - Speidl, Walter S.
AU - Vilahur, Gemma
AU - Pinero, Antonio
AU - Cimmino, Giovanni
AU - García, Mario J.
AU - Fuster, Valentin
AU - Sanz, Javier
AU - Badimon, Juan J.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/6
Y1 - 2007/6
N2 - BACKGROUND - β-Blockers improve clinical outcome when administered early after acute myocardial infarction. However, whether β-blockers actually reduce the myocardial infarction size is still in dispute. Cardiac magnetic resonance imaging can accurately depict the left ventricular (LV) ischemic myocardium at risk (T2-weighted hyperintense region) early after myocardial infarction, as well as the extent of necrosis (delayed gadolinium enhancement). The aim of this study was to determine whether early administration of metoprolol could increase myocardial salvage, measured as the difference between the extent of myocardium at risk and myocardial necrosis. METHODS AND RESULTS - Twelve Yorkshire pigs underwent a 90-minute left anterior descending coronary occlusion, followed by reperfusion. They were randomized to metoprolol (7.5 mg during myocardial infarction) or placebo. Global and regional LV function, extent of myocardium at risk, and myocardial necrosis were quantified by cardiac magnetic resonance imaging studies performed 4 and 22 days after reperfusion in 10 survivors. Despite similar extent of myocardium at risk in metoprolol- and placebo-treated pigs (30.9% of LV versus 30.6%; P=NS), metoprolol resulted in 5-fold-larger salvaged myocardium (32.4% versus 6.2% of myocardium at risk; P=0.015). The LV ejection fraction significantly improved in metoprolol-treated pigs between days 4 and 22 (37.2% versus 43.0%; P=0.037), whereas it remained unchanged in pigs treated with placebo (35.1% versus 35.0%; P=NS). The extent of myocardial salvage was related directly to LV ejection fraction improvement (P=0.031) and regional LV wall motion recovery (P=0.039) at day 22. CONCLUSIONS - Early metoprolol administration during acute coronary occlusion increases myocardial salvage. The extent of myocardial salvage, measured as the difference between myocardium at risk and myocardial necrosis, was associated with regional and global LV motion improvement.
AB - BACKGROUND - β-Blockers improve clinical outcome when administered early after acute myocardial infarction. However, whether β-blockers actually reduce the myocardial infarction size is still in dispute. Cardiac magnetic resonance imaging can accurately depict the left ventricular (LV) ischemic myocardium at risk (T2-weighted hyperintense region) early after myocardial infarction, as well as the extent of necrosis (delayed gadolinium enhancement). The aim of this study was to determine whether early administration of metoprolol could increase myocardial salvage, measured as the difference between the extent of myocardium at risk and myocardial necrosis. METHODS AND RESULTS - Twelve Yorkshire pigs underwent a 90-minute left anterior descending coronary occlusion, followed by reperfusion. They were randomized to metoprolol (7.5 mg during myocardial infarction) or placebo. Global and regional LV function, extent of myocardium at risk, and myocardial necrosis were quantified by cardiac magnetic resonance imaging studies performed 4 and 22 days after reperfusion in 10 survivors. Despite similar extent of myocardium at risk in metoprolol- and placebo-treated pigs (30.9% of LV versus 30.6%; P=NS), metoprolol resulted in 5-fold-larger salvaged myocardium (32.4% versus 6.2% of myocardium at risk; P=0.015). The LV ejection fraction significantly improved in metoprolol-treated pigs between days 4 and 22 (37.2% versus 43.0%; P=0.037), whereas it remained unchanged in pigs treated with placebo (35.1% versus 35.0%; P=NS). The extent of myocardial salvage was related directly to LV ejection fraction improvement (P=0.031) and regional LV wall motion recovery (P=0.039) at day 22. CONCLUSIONS - Early metoprolol administration during acute coronary occlusion increases myocardial salvage. The extent of myocardial salvage, measured as the difference between myocardium at risk and myocardial necrosis, was associated with regional and global LV motion improvement.
KW - Imaging
KW - Magnetic resonance imaging
KW - Metoprolol
KW - Myocardial infarction
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U2 - 10.1161/CIRCULATIONAHA.106.679639
DO - 10.1161/CIRCULATIONAHA.106.679639
M3 - Article
C2 - 17515460
AN - SCOPUS:34250367541
SN - 0009-7322
VL - 115
SP - 2909
EP - 2916
JO - Circulation
JF - Circulation
IS - 23
ER -