Myocardial energy depletion and dynamic systolic dysfunction in hypertrophic cardiomyopathy

Ormerod, Julian O. M., Frenneaux, Michael P. and Sherrid, Mark V. (2016) Myocardial energy depletion and dynamic systolic dysfunction in hypertrophic cardiomyopathy. Nature Reviews Cardiology, 13 (11). 677–687. ISSN 1759-5002

[img]
Preview
PDF (Accepted manuscript) - Submitted Version
Available under License ["licenses_description_other" not defined].

Download (590kB) | Preview

Abstract

Evidence indicates that anatomical and physiological phenotypes of hypertrophic cardiomyopathy (HCM) stem from genetically mediated, inefficient cardiomyocyte energy utilization, and subsequent cellular energy depletion. However, HCM often presents clinically with normal left ventricular (LV) systolic function or hyperkinesia. If energy inefficiency is a feature of HCM, why is it not manifest as resting LV systolic dysfunction? In this Perspectives article, we focus on an idiosyncratic form of reversible systolic dysfunction provoked by LV obstruction that we have previously termed the 'lobster claw abnormality' — a mid-systolic drop in LV Doppler ejection velocities. In obstructive HCM, this drop explains the mid-systolic closure of the aortic valve, the bifid aortic pressure trace, and why patients cannot increase stroke volume with exercise. This phenomenon is characteristic of a broader phenomenon in HCM that we have termed dynamic systolic dysfunction. It underlies the development of apical aneurysms, and rare occurrence of cardiogenic shock after obstruction. We posit that dynamic systolic dysfunction is a manifestation of inefficient cardiomyocyte energy utilization. Systolic dysfunction is clinically inapparent at rest; however, it becomes overt through the mechanism of afterload mismatch when LV outflow obstruction is imposed. Energetic insufficiency is also present in nonobstructive HCM. This paradigm might suggest novel therapies. Other pathways that might be central to HCM, such as myofilament Ca2+ hypersensitivity, and enhanced late Na+ current, are discussed.

Item Type: Article
Uncontrolled Keywords: cardiac hypertrophy,echocardiography,pathogenesis
Faculty \ School: Faculty of Medicine and Health Sciences > Norwich Medical School
Related URLs:
Depositing User: Pure Connector
Date Deposited: 24 Sep 2016 00:17
Last Modified: 11 Jun 2020 00:03
URI: https://ueaeprints.uea.ac.uk/id/eprint/59961
DOI: 10.1038/nrcardio.2016.98

Actions (login required)

View Item View Item