Cardiomyocyte transverse tubule loss leads the way to heart failure.

Evaluation of: Wei S, Guo A, Chen B et al.: T-tubule remodeling during transition from hypertrophy to heart failure. Circ. Res. 107(4), 520-531 (2010). The highly organized transverse (T)-tubule membrane system in ventricular myocytes plays an integral role in excitation-contraction coupling, and disruption of this T-tubule network has been implicated in contractile dysfunction in heart failure. Wei and colleagues used advanced confocal imaging techniques to evaluate cardiomyocyte membrane structure in intact rat hearts following surgically induced pressure overload, and demonstrated a loss of integrity of the T-tubule system. Importantly, this T-tubule dropout was detected early in the disease process, at the stage of compensated hypertrophy before observable ventricular dysfunction, and then progressed in proportion to the severity of the systolic dysfunction. These findings provide a new insight into the critical transition from compensated hypertrophy to heart failure and suggests important future areas for investigation.