Predictive value of regional left ventricular circumferential shortening in jeopardized myocardium. A two-dimensional SPAMM cine-MRI study in a canine model.
OBJECTIVE
To determine whether myocardial circumferential shortening assessed in the different myocardial layers by SPAMM cine-MRI may help to discriminate between various degrees of myocardial injury in reperfused myocardium.


METHODS
Dogs underwent 90 minutes of coronary occlusion and 24 hours of reperfusion. Using a 1.5 T whole-body MR scanner, SPAMM cine-MRI images were acquired before and 24 hours after surgery on the short axis plan of the left ventricle and analyzed to evaluate the mean myocardial circumferential shortening (% MCS) in the different layers. Based on the residual blood flow, animals were assigned to group I (residual flow < 22.5%) or group II (residual flow > 22.5%).


RESULTS
Dogs in group I developed larger infarctions (25.3% +/- 14.6 of the area at risk, n = 5) compared with those in group II (5.81% +/- 1.1, n = 7, P < 0.05). In the jeopardized zone, the % MCS of the subendocardium decreased more significantly in group I (-0.03% +/- 3.7 to 2.2% +/- 5.2) compared with group II (14.7% +/- 1.5 to 18.4% +/- 1.4).


CONCLUSIONS
SPAMM cine-MRI is a fast and noninvasive means of measuring % MCS. The MR measurement of this parameter in the subendocardial layer appears quite accurate in describing the degree of damage in reperfused myocardium.
Verhnet
H
H
Laboratoire Creatis, Hôpital Cardiologique, Lyon, France.
Revel
D
D
Arteaga
C
C
Clarysse
P
P
Sottilini
F
F
Roux
J P
JP
Canet
E
E
D000465:Algorithms; D000818:Animals; D003331:Coronary Vessels / Q000502:physiology; D004285:Dogs; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D009200:Myocardial Contraction / Q000502:physiology*; D009203:Myocardial Infarction / Q000503:physiopathology*; D015425:Myocardial Reperfusion; D011237:Predictive Value of Tests; D012039:Regional Blood Flow; D018709:Statistics, Nonparametric; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*