Adenosine-Sensitive Upper Septal Fascicular Ventricular Tachycardia Associated With Takotsubo Syndrome

We describe a rare case of upper septal fascicular ventricular tachycardia (VT) associated with takotsubo syndrome that failed to convert with synchronized shock but converted to normal sinus rhythm after intravenous adenosine administration. The excess catecholamine state of takotsubo syndrome likely provided substrate for cyclic adenosine monophosphate–mediated triggered activity, causing fascicular VT.