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Published on: May 12, 2023
Myocardial Efficiency: A Fundamental Physiological Concept on the Verge of Clinical Impact
Jens Sörensen1, Hendrik Johannes Harms2, John M Aalen3
1Department of Nuclear Medicine and PET, Surgical Sciences, Uppsala University, Sweden; Department of Nuclear Medicine and PET, Clinical Institute, Aarhus University, Aarhus, Denmark.
Abstract:
Myocardial external efficiency is the relation of mechanical energy generated by the left (or right) ventricle to the consumed chemical energy from aerobic metabolism. Efficiency can be calculated invasively, and, more importantly, noninvasively by using positron emission tomography, providing a single parameter by which to judge the adequacy of myocardial metabolism to generated mechanical output. This parameter has been found to be impaired in heart failure of myocardial or valvular etiology, and it changes in a characteristic manner with medical or interventional cardiac therapy. The authors discuss the concept, strengths, and limitations, known applications, and future perspectives of the use of myocardial efficiency.
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