Cardiac geometry and mass changes associated with pacing-induced cardiomyopathy in the dog.
We evaluated the effects of chronic rapid pacing (240 beats/min) on ventricular geometry and function and on cardiac mass in a canine model. Forty dogs were studied by two-dimensional echocardiography before and after 45 days of pacing. Compared with sham-operated control animals, the paced animals had significant increases in end-diastolic and end-systolic volume and a decrease in ejection fraction. The increase in ventricular volume was primarily the result of dilation of the short axis of the ventricular lumen, without significant changes in the long-axis dimension. Paced animals had biatrial hypertrophy but no change in ventricular or total cardiac mass.
Scott
B D
BD
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City.
Sharma
M K
MK
Levett
J M
JM
Marinelli
C C
CC
Kieso
R A
RA
Schmid
P G
PG
Kerber
R E
RE
D000818:Animals; D002304:Cardiac Pacing, Artificial / Q000379:methods; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*; D004285:Dogs; D004452:Echocardiography; D006321:Heart / Q000502:physiology*; D006352:Heart Ventricles