A109.E1022

JACC March 9, 2010

Volume 55, issue 10A

MYOCARDIAL ISCHEMIA AND INFARCTION

CORRELATION BETWEEN MICROVASCULAR OBSTRUCTION AND INDEX OF MICROCIRCULATORY

RESISTANCE FOR ASSESSMENT OF MICROVASCULAR DYSFUNCTION IN PATIENTS WITH ACUTE

MYOCARDIAL INFARCTION

ACC Poster ContributionsGeorgia World Congress Center, Hall B5

Sunday, March 14, 2010, 3:30 p.m.-4:30 p.m.

Session Title: Vascular Biology of Myocardial Ischemia/InfarctionAbstract Category: Myocardial Ischemia/Infarction--Basic

Presentation Number: 1102-293

Authors: Jong Hoon Koh, Duk Kyu Cho, Hee Woo Lee, Miyoung Kim, Kwandong University Mongji Hospital, Goyang, South Korea, Goyang, South Korea

Background: Coronary flow measurements might be insensitive to small amounts of microvascular obstruction(MO) and it is important in the

evaluation of the severity and extent of myocardial damage. Therefore, we studied the relation between the presence of microvascular obstruction,

intracoronary wedge pressure measurements and a index of microcirculatory resistance (IMR) for assessment of microvascular dysfunction in acute

myocardial infarction treatment by primary PCI.

Methods: We enrolled 40 consecutive patients who underwent primary percutaneous coronary intervention(PCI) for acute myocardial infarction

patients. After successful PCI, using a pressure- temperature sensor-tipped coronary wire, the thermodilution-derived CFR(CFR-thermo) and coronary

wedge pressure(Pcw) were measured and mean aortic pressure(Pcw/Pa) was calculated, along with IMR. There measurements were related to

microvascualr obstruction (MO) and infarct size were assessed with cardiac magnetic resonance imagine (MRI).

Results: We were divided into two groups according to the present of MO on the MRI: no- MO group (MRI with homogeneous enhancement of

myocardium;n= 20), and MO group( MRI with hypoenhanced region; n = 20) . The extent of MO correlated with IMR (r = 0.67; p = 0.002), Pcw (r

=0.41; p = 0.001), and Pcw/Pa of the infarct-related artery (r = 0.46; p = 0.002). An inverse relation was observed between the extent of MO and

CFR-thermo (r=-0.39 p=0.016). Multivariate regression analyses showed that the extent of MO was the only independent factor related to both Pcw/

Pa and IMR.

Conclusions: The extent of MO as assessed by cardiac MRI correlated well with intracoronary pressure parameters and IMR. There might be a

useful predictor microvascular dysfunction during the acute phase of myocardial infarction.