Abstract 20337: Implications of Invasively Measured Coronary Flow Reserve on Infarct Size Directly Following Reperfusion After Acute Myocardial Infarction in Both Humans and an Experimental Pig Model
Introduction: An impaired coronary flow reserve (CFR) directly after primary PCI for treatment of acute myocardial infarction (AMI), is related to a worse clinical outcome. The prognostic relevance of CFR for early and late functional outcome and furthermore, the individual contribution of both the baseline and hyperemic component to CFR were investigated in this study.
Methods: Intracoronary Doppler flow velocity measurements were obtained both before and directly after 90 minute balloon occlusion, with subsequent reperfusion, of the circumflex artery in an AMI pig model (n=11) and also directly after successful PCI in humans (n=34). Stable patients free from angiographic coronary artery disease served as a control group (n=134). CFR was defined as the ratio between hyperemic and basal average peak velocity (h-APV and b-APV). We correlated CFR to histological infarct size as percentage of left ventricle (IS%LV) in pigs at 7 days, and to 7 day and 3 month IS%LV as defined by cardiac magnetic resonance imaging in humans.
Results: CFR was significantly correlated to IS%LV in both pigs (r = -0.61; p=0.048) and humans (r = -0.44; p<0.01 at 7 day and r = -0.40; p=0.03 at 3 months). In pigs, CFR decreased after induction of AMI (2.4±0.9 vs. 1.5±0.4; p=0.04 for pre and post AMI respectively) and this finding was consistent for the human situation (2.7±0.7 vs. 1.8±0.9; p<0.001 for control vs. AMI patients). Both components of CFR contributed to its reduction after reperfusion (in pigs, b-APV increased by 8 and h-APV decreased by 6 cm/s, while in humans, b-APV increased by 5 and h-APV decreased by 7 cm/s).
Conclusions: A decrease in CFR is related to a larger infarct size and is observed in both patients as well as in healthy pig model of reperfused AMI, suggesting that pre-existing microvascular dysfunction does not explain the decreased CFR.
- Acute coronary syndromes
- Coronary microcirculation
- Myocardial infarction, STEMI
- Cardiac MRI
- Interventional cardiology
Author Disclosures: G. de Waard: None. P.F. Teunissen: None. M.R. Hollander: None. M.F. Jansen: None. L. Robbers: None. P. Knaapen: None. N. van Royen: None.
- © 2014 by American Heart Association, Inc.