Relationship between the extent of non-viable myocardium and regional left ventricular function in chronic ischemic heart disease.
OBJECTIVE
To define the relationship between left ventricular (LV) regional contractile function and the extent of myocardial scar in patients with chronic ischemic heart disease and multi-vessel coronary artery disease.


METHODS
Twenty-three patients with chronic ischemic heart disease and 5 healthy volunteers underwent magnetic resonance imaging (MRI). In patients, the relative area (Percent Scar) and transmural extent (Transmurality) of myocardial infarction were computed from short-axis delayed enhancement images. In each image, myocardial segments were categorized based on the extent of infarction they contained, with 6 categories each for Percent Scar and Transmurality: normal, from healthy volunteers; and 0%; 1-25%, 26-50%, 51-75%, and > 76% from patients. In patients and volunteers, regional LV function was quantified by absolute systolic wall thickening from cine images and midwall circumferential strain using tagged images.


RESULTS
Compared to normal segments, regional LV function in patients was significantly diminished in all scar extent intervals, with wall thickening < or = 1 mm and strain > or = -8% for all categories. Systolic wall thickening was reduced significantly in all categories above 50% Percent Scar and above 25% Transmurality in patients, relative to corresponding 0% categories. Circumferential strain was significantly reduced above 25% Percent Scar and above 25% Transmurality.


CONCLUSIONS
In patients with chronic ischemic heart disease and multi-vessel coronary artery disease, wall thickening was more sensitive to changes in scar Transmurality than to changes in Percent Scar. However, circumferential strain was equally sensitive to both indices. In general, circumferential strain was more sensitive than wall thickening to increases in scar extent.
Kolipaka
Arunark
A
Section of Cardiovascular Imaging, Division of Radiology, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Chatzimavroudis
George P
GP
White
Richard D
RD
Lieber
Michael L
ML
Setser
Randolph M
RM
D002302:Cardiac Output; D016022:Case-Control Studies; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000473:pathology*; D009206:Myocardium / Q000473:pathology*; D013599:Systole; D018487:Ventricular Dysfunction, Left / Q000473:pathology*
D003287:Contrast Media; D019786:Gadolinium DTPA