Recovery of Cardiac Function in Cardiomyopathy Caused by Titin Truncation

Recovery of Cardiac Function in Cardiomyopathy Caused by Titin TruncationDilated cardiomyopathy (DCM) is a frequent cause of heart failure and a common indication for heart transplantation.Dilated cardiomyopathy has a strong genetic basis, and the most common disease-causing mutations are variants that truncate the sarcomeric protein titin (TTN-truncating variants [TTNtvs] are prevalent in 25% 1 of familial DCM cases and 13% 2 of idiopathic DCM cases).The prognosis of DCM is poor, but functional recovery from end-stage failure has been reported following both optimal medical therapy 3 and left ventricular assist device (LVAD) support, 4,5 although the determinants of successful recovery are unknown.It has been proposed that recovery from genetic cardiomyopathy may not be expected because the underlying cause is irre-versible, whereas recovery may be more likely when DCM is caused by reversible, nongenetic factors (eg, myocarditis). 6 To address this directly, we sequenced TTN in patients with end-stage DCM who either recovered or did not recover following LVAD support.