Metabolic changes in hypertrophic cardiomyopathies: scientific update from the Working Group of Myocardial Function of the European Society of Cardiology

Figures

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  Figure 1. Excitation-contraction coupling in a healthy heart. Contraction is initiated upon Ca2+ entry in the muscle cell, which activates Ca2+ release from the SR. Ca2+ binds to the myofilaments, which causes contraction. To relax Ca2+ detaches from myofilaments and is pumped back into the SR. A small fraction of Ca2+ is removed out of the cell via the Na+-Ca2+ exchanger (NCX). Mitochondria take care of sufficient ATP needed for proper contraction and relaxation of cardiomyocytes. In the healthy heart, CK catalyses the transfer of phosphate from phosphocreatine to ADP, thereby regenerating ATP, while preventing accumulation of cytosolic ADP.

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  Figure 2. Excitation-contraction coupling in diseased heart and possible targets for therapy. Mutation-induced changes in myofilament properties increase ATP utilization. Cellular metabolism changes as a consequences of mutation-induced and ADP-mediated increases in myofilament Ca2+-sensitivity, impaired mitochondrial function and reduced creatine kinase activity. Different therapies may target impaired metabolism in HCM.