Long-Term Outcome of the First Completely Leadless Cardiac Resynchronization Therapy in the United States.

Completely leadless cardiac resynchronization therapy is feasible with the combination of Micra AV pacemaker (Medtronic Inc) and WiSE-CRT (EBR Inc) systems. Several reports have highlighted this combination in Europe. This case report presents a 1- year follow-up the first reported concomitant use of the leadless systems in the United States. (Level of Difficulty: Advanced.).

QT Prolongation After His Bundle Pacing: What Is the Mechanism?

An 82-year-old woman with nonischemic cardiomyopathy underwent cardiac resynchronization therapy by the use of His bundle pacing. After the procedure, the patient had repolarization abnormality with severely prolonged QTc and anterior inferior T-wave inversions, likely resulting from memory T waves associated with the correction of long-standing left bundle branch block. These changes could be potentially arrhythmogenic. (Level of Difficulty: Intermediate.).