Abstract 17805: Efficacy of Collateral Circulation in Patients with Acute Coronary Syndrome Treated with Primary Percutaneous Coronary Intervention
Background: Collateral circulation has been reported to be related to a better outcome in patients with coronary artery disease. However, the efficacy of collateral circulation remains unclear in patients with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI).
Method: We investigated 139 patients with ACS (acute myocardial infarction; n=108, unstable angina; n=31) who underwent primary PCI. We divided the patients into two groups according to the formation of collateral circulation; patients with rich collateral (Rentrop grade 2-3) (rich-coll) and with poor collateral (Rentrop grade 0-1) (poor-coll). Baseline characteristics, intravascular ultrasound (IVUS) and angiographical findings including TIMI flow, corrected TIMI frame counts (CTFCs) and myocardial blush grades (MBG) were examined. The efficacy of collateral circulation was evaluated according to the antegrade coronary flow grade of each lesion.
Result: Thirty-four patients (24.5%) had rich collateral circulation. In patients with occluded culprit arteries (initial TIMI flow 0-1, n=74), rich-coll patients (n=26, 35.1%) had a significantly higher CK levels on admission (969±1249 IU/l vs. 225±421 IU/l, p=0.0003), greater plaque volume of necrotic-core (NC) by IVUS (60.6±32.2 mm3 vs. 42.7±32.8 mm3, p=0.05) and a higher frequency of transient slow-flow phenomenon during PCI than poor-coll patients (38.5% vs. 16.7%, p=0.049). However, outcomes after PCI were similar among the groups (final CTFC>27; 44.0% vs. 42.6%, p=1.00, MBG 0-1; 57.7% vs. 56.3%, p=1.00 and max CK levels; 3337±2864 IU/l vs. 4147±3337 IU/l, p=0.30). On the other hand, in patients with non-occluded culprit arteries (TIMI flow 2-3, n=65), rich-coll patients (n=8, 12.3%) showed a tendency of better outcome after PCI including coronary flow (final CTFC>27; 0.0% vs. 29.8%, p=0.099) and myocardial perfusion (MBG 0-1; 0.0% vs. 24.6%, p=0.18), although CK levels on admission (187±122 IU/l vs. 258±289 IU/l, p=0.50) and NC volume by IVUS (41.4±42.6 mm3 vs. 36.6±28.5 mm3, p=0.69) were similar.
Conclusion: In ACS patients, the existence of rich collateral circulation might reduce the influences of several risk factors including IVUS findings on worse outcomes after PCI.
- Acute coronary syndromes
- Percutaneous coronary intervention
- Collateral circulation
- Intravascular ultrasound/Doppler
- © 2011 by American Heart Association, Inc.