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Updated: Jul 13, 2026

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Cardiac geometry and mass changes associated with pacing-induced cardiomyopathy in the dog
B D Scott1, M K Sharma, J M Levett
1Department of Internal Medicine, University of Iowa College of Medicine, Iowa City.
Abstract:
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.
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