TCAP and heart failure: T‐t morphology and coordination are known to be regulated by a multitude of proteins.11 Notably, the scaffold protein, bridging integrator 1 (BIN‐1), has been shown to be central to t‐t biogenesis,12 trafficking of the L‐type voltage‐gated calcium channel to the t‐ts,13 and, more recently, folding of the t‐t inner membrane to limit ion diffusion.14 Depressed BIN‐1 expression has been identified in models of heart failure and linked to arrhythmogenesis.15, 16 The proteins, telethonin (T‐cap)17 and tropomyosin (Tpm),18 are proposed to link the t‐ts to the cytsoskeleton.