Impact of coronary artery collaterals on infarct size assessed by serial cardiac magnetic resonance imaging after primary percutaneous coronary intervention in patients with acute myocardial infarction.
OBJECTIVE
Coronary collaterals have been shown to protect ischemic myocardium from necrosis in patients with acute myocardial infarction (AMI). We sought to determine the impact of collateral circulation on infarct size in AMI using serial cardiac magnetic resonance (CMR).


METHODS
A total of 46 anterior AMI patients (age, 58.9+/-10.6 years; male 72.3%) undergoing primary percutaneous coronary intervention (PCI) were investigated. The infarct size was measured on serial CMR performed within 7 days after primary PCI (acute stage) and 3 months later (chronic stage).


RESULTS
Thirty-four patients (73.9%) showed collateral flow before primary PCI. CMR taken at the acute stage showed no significant difference in infarct size between two groups. However, follow-up CMR revealed significantly smaller percentage of infarct thickness (51.8+/-14.0 vs. 62.5+/-11.7%, P = 0.035) and mass (22.3+/-9.9 vs. 30.9+/-11.6%, P = 0.042) in patients with collaterals. There were significant changes from the acute to chronic stage regarding left ventricular end-systolic (-18.2+/-10.0 vs. 0.8+/-2.5 ml, P = 0.022) and end-diastolic volume (-14.8+/-9.2 vs. 2.6+/-13.7 ml, P = 0.031), percentage of infarct mass (-6.1+/-2.8 vs. -0.8+/-1.1%, P = 0.034), and thickness (-8.9+/-3.3 vs. -3.1+/-2.8%, P = 0.029) in collateral group compared with noncollateral group on serial CMR.


CONCLUSIONS
Serial CMR revealed the effect of collaterals in patients with AMI on reduction of infarct size and improvement of myocardial remodeling at the chronic stage.
Yoon
Se-Jung
SJ
Division of Cardiology, National Health Insurance Corporation Ilsan Hospital, Goyang, Korea.
Ko
Young-Guk
YG
Kim
Jung-Sun
JS
Moon
Jae-Youn
JY
Kim
Young-Jin
YJ
Park
Sungha
S
Ha
Jong-Won
JW
Choi
Donghoon
D
Jang
Yangsoo
Y
Chung
Namsik
N
Shim
Won-Heum
WH
Cho
Seung-Yun
SY
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D056988:Anterior Wall Myocardial Infarction / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D003097:Collateral Circulation; D003287:Contrast Media; D017023:Coronary Angiography; D003326:Coronary Circulation; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D011446:Prospective Studies; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling
D003287:Contrast Media; D019786:Gadolinium DTPA