Usefulness of the index of microcirculatory resistance for invasively assessing myocardial viability immediately after primary angioplasty for anterior myocardial infarction.
OBJECTIVE
The aim of this study is to evaluate the usefulness of the index of microcirculatory resistance (IMR) for predicting myocardial viability and left ventricular (LV) function recovery in acute myocardial infarction (AMI).


RESULTS
After successful primary percutaneous coronary intervention in 40 patients with anterior AMI, IMR was measured using a pressure-temperature sensor-tipped coronary guidewire. Myocardial viability was quantified by 18F-fluorodeoxyglucose (FDG) positron emission tomography in 38 patients. Echocardiographic regional wall motion was analysed to calculate the anterior wall motion score (A-WMS) and percent change in A-WMS after revascularization and at 6-month follow-up. IMR correlated significantly with regional myocardial FDG uptake (r = -0.738, P < 0.001) and it demonstrated significant correlation with percent change in A-WMS (r = -0.464, P = 0.003). The area under the receiver operating curve of IMR for predicting LV function recovery was 0.89 [95% CI 0.888-0.894].


CONCLUSIONS
Index of microcirculatory resistance, a new index representing microvascular integrity, is a reliable early on-site determinant of myocardial viability and LV recovery after primary stenting for AMI.
Lim
Hong-Seok
HS
Department of Cardiology, Ajou University Medical Center, Yeongtong-gu, Suwon 443-721, Republic of Korea.
Yoon
Myeong-Ho
MH
Tahk
Seung-Jea
SJ
Yang
Hyoung-Mo
HM
Choi
Byoung-Joo
BJ
Choi
So-Yeon
SY
Sheen
Seung-Soo
SS
Hwang
Gyo-Seung
GS
Kang
Soo-Jin
SJ
Shin
Joon-Han
JH
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D056988:Anterior Wall Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D003326:Coronary Circulation / Q000502:physiology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006321:Heart / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D014022:Tissue Survival; D014655:Vascular Resistance / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18