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Updated: Jun 13, 2026
06:22
Contractility Measurements on Isolated Papillary Muscles for the Investigation of Cardiac Inotropy in Mice
Published on: September 17, 2015
Bigeminy and the bifid papillary muscle
1Department of Physiology, University of Pretoria, Pretoria, South Africa. jker@wol.co.za
Cardiovascular Ultrasound
|April 23, 2010
Summary
A newly identified bifid papillary muscle variant in the left ventricle may cause frequent ventricular premature complexes. This finding offers new insights into cardiac electrical abnormalities and their structural origins.
Area of Science:
- Cardiology
- Cardiac Anatomy
- Electrophysiology
Background:
- Structural anomalies of left ventricular papillary muscles are increasingly recognized.
- Some anomalies are associated with electrocardiographic aberrations, including premature ventricular complexes.
Observation:
- Previous reports linked the posterior papillary muscle base to frequent premature ventricular complexes.
- This study describes a novel structural variant: the bifid papillary muscle of the anterior papillary muscle.
Findings:
- The bifid papillary muscle is proposed as the source of frequent ventricular premature complexes.
- These complexes presented as bigeminy in a patient with preserved left ventricular function.
Implications:
- This discovery expands the understanding of papillary muscle variations and their role in cardiac arrhythmias.
- It highlights the anterior papillary muscle as a potential source of ventricular ectopy, even with normal ventricular function.
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