Relationship of contractile function to transmural extent of infarction in patients with chronic coronary artery disease.
OBJECTIVE
We sought to determine the relationship of contractile function to the transmural extent of infarction (TEI) in patients with chronic coronary artery disease.


BACKGROUND
In the setting of reperfused, chronic myocardial infarction (MI), the relationship of contractile function to the TEI has not been established.


METHODS
We studied function by cine magnetic resonance imaging (MRI) and the TEI by contrast-enhanced MRI in 31 patients with single-vessel disease 162 +/- 62 days after reperfused first MI.


RESULTS
Of all 516 segments with MI, blinded observers were unable to detect abnormal thickening in 193 (37%), and wall thickening measured quantitatively in these segments was 66 +/- 28%. Of the 193 segments, 163 (84%) were infarcts limited to the subendocardium. The average TEI reached 53% before half of the patients had abnormal contractile function. When patients with small MI (< or =5% of total left ventricular [LV] mass) were excluded, the average TEI reached 43% before half the patients had abnormal function. In subjects with small MI (< or =5% of total LV mass [n = 13]), even segments with TEI >75% had normal function (14 of 14) because they were surrounded by normally moving neighbor segments.


CONCLUSIONS
In the setting of reperfused chronic MI, the TEI approaches 50% before contractile dysfunction can be systematically identified. Contractile function cannot be used to rule out chronic MI.
Mahrholdt
Heiko
H
Feinberg Cardiovascular Research Institute, Chicago, Illinois, USA.
Wagner
Anja
A
Parker
Michele
M
Regenfus
Matthias
M
Fieno
David S
DS
Bonow
Robert O
RO
Kim
Raymond J
RJ
Judd
Robert M
RM
D000328:Adult; D000368:Aged; D002908:Chronic Disease; D003324:Coronary Artery Disease / Q000150:complications*; D005260:Female; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D009203:Myocardial Infarction / Q000209:etiology / Q000503:physiopathology*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology*; D016276:Ventricular Function / Q000502:physiology