Delayed ventricular pacing failure and correlations between pacing thresholds, left ventricular ejection fraction, and QTc values in a male with Takotsubo cardiomyopathy.

This is one of the first cases of delayed transient ventricular pacing failure in a male patient with transient left ventricular apical ballooning, in the presence of spared right ventricular function. Given the possibility of acute transient anomalies in myocardial impedance and pacing failure even in the subacute phase of TC several weeks after clinical onset of transient systolic dysfunction, pacing threshold should be carefully monitored in subjects with TC, both during the acute phase of the disease and in first months of follow-up after discharge. Ventricular pacing threshold correlated directly to QTc values and inversely to left ventricular ejection fraction over time.