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Updated: Jun 19, 2026

Contractility Measurements on Isolated Papillary Muscles for the Investigation of Cardiac Inotropy in Mice
Published on: September 17, 2015
The accessory papillary muscle with inferior J-waves--peculiarity or hidden danger?
1Department of Physiology, University of Pretoria, Pretoria, South Africa. jker@wol.co.za
Abstract:
Originally described in 1953, today the so-called J-wave is the source of much controversy. As a marker of so-called "early repolarization", this variant has been regarded as a totally benign variant since the 1960's. However, since then a wealth of data have indicated that the J-wave may be a marker of a highly arrhythmogenic substrate with a resultant high risk of sudden cardiac death.In this case report a case of an accessory papillary muscle with a prominent J-wave is described. This may be the first of many possible cases where papillary muscle variants may be the cause of the J-wave.
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