Ambulatory Electrocardiographic Monitoring for the Detection of High-Degree Atrio-Ventricular Block in Patients With New-onset PeRsistent LEft Bundle Branch Block After Transcatheter Aortic Valve Implantation. The "MARE" Study

This is a prospective observational study including patients undergoing TAVI with either self- or balloon-expandable valves. After the procedure, patients will be on ECG monitoring during the hospitalization period (or at least 72 hours), and an ECG will be performed daily until hospital discharge in all patients. Patients with new-onset persistent LBBB at hospital discharge (new-onset LBBB of a duration of at least 48 h which persists at hospital discharge, at least 3 days and up to 15 days after the procedure) will receive an implantable loop recorder Reveal ICM LINQ®, which will be implanted subcutaneously to record adequate QRS complexes and P waves. The patients will be followed in outpatient clinic visits at 1, 12, 24 and 36 months after TAVR, or if symptoms suggestive of cardiac origin or relevant arrhythmic events occur. The device will be manually interrogated in each visit. Phone contacts will be also carried out every three months.

Inclusion criteria

-Patients undergoing TAVI with either balloon or self-expandable valves who develop new-onset LBBB persistent at hospital discharge, at least 3 days after the procedure

Exclusion criteria

• Failure to provide informed consent
• Baseline pacemaker/defibrillator or pacemaker/defibrillator implanted during the hospitalization period following the TAVI procedure
• Pre-existing complete LBBB
• Patients with a life-expectancy of less than 2 years