Accuracy of echocardiographic estimates of left ventricular mass in mice.
Genetically modified mice have created the need for accurate noninvasive left ventricular mass (LVM) measurements. Recent technical advances provide two-dimensional images adequate for LVM calculation using the area-length method, which in humans is more accurate than M-mode methods. We compared the standard M-mode and area-length methods in mice over a wide range of LV sizes and weights (62-210 mg). Ninety-one CD-1 mice (38 normal, 44 aortic banded, and 9 inherited dilated cardiomyopathy) were imaged transthoracically (15 MHz linear transducer, 120 Hz). Compared with necropsy weights, area-length measurements showed higher correlation than the M-mode method (r = 0.92 vs. 0.81), increased accuracy (bias +/- SD: 1.4 +/- 27.1% vs. 36.7 +/- 51.6%), and improved reproducibility. There was no significant difference between end-systolic and end-diastolic estimates. The truncated ellipsoid estimation produced results similar in accuracy to the area-length method. Whereas current echocardiographic technology can accurately and reproducibly estimate LVM with the two-dimensional, area-length formula in a variety of mouse models, additional technological improvements, rather than refinement of geometric models, will likely improve the accuracy of this methodology.
Collins
K A
KA
Noninvasive Cardiac Imaging Laboratory, University of Chicago, Chicago, Illinois 60637, USA.
Korcarz
C E
CE
Shroff
S G
SG
Bednarz
J E
JE
Fentzke
R C
RC
Lin
H
H
Leiden
J M
JM
Lang
R M
RM
D000818:Animals; D001011:Aorta; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000473:pathology; D002908:Chronic Disease; D004195:Disease Models, Animal; D004452:Echocardiography / Q000379:methods / Q000592:standards* / Q000706:statistics & numerical data; D005260:Female; D006352:Heart Ventricles / Q000473:pathology; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008822:Mice, Transgenic; D009206:Myocardium / Q000473:pathology*; D015588:Observer Variation; D015203:Reproducibility of Results