Resolution of severe dilated cardiomyopathy with significant arrhythmia burden using hydroquinidine, in addition to guideline-directed medical therapy, in a patient with a pathogenic <i>SCN5A</i> variant: a case report

This atypical presentation of a cardiomyopathy was driven, at least in part, by the patient's extensive arrhythmia. Previous research has shown variable, short-term effects of sodium channel antagonists in familial p.R814W variants. Contrastingly, in our patient, sustained and long-term improvement was observed with the use of hydroquinidine. Close multidisciplinary team working and early genetic testing facilitated personalized care in our patient's case, resulting in a favourable outcome.