Author + information
- Sheldon M. Singh, MD∗ (, )
- William K. Chan, MD and
- Asaf Danon, MD
- ↵∗Sunnybrook Health Sciences Centre, Faculty of Medicine, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
Rodés-Cabau et al. (1) recently reported on the global arrhythmia burden determined using continuous arrhythmia monitoring with an implantable loop recorder (ILR) in patients with new-onset left bundle branch block following transcatheter aortic valve replacement (TAVR). In this relatively small observational study approximately 17% of TAVR patients with new left bundle branch block developed atrial fibrillation/flutter, and 13%, ventricular arrhythmias in 1-year follow-up. These findings are consistent with the combined experience at our centers in post-TAVR patients with atrioventricular block who required dual-chamber pacemakers (new-onset atrial fibrillation = 25%; ventricular arrhythmias 6 to 30 s = 5%). Rodés-Cabau et al. (1) also report a 20% incidence of severe bradycardia, including 15% of patients who developed high-grade atrioventricular block (HAVB).
Intensive monitoring undoubtedly will reveal arrhythmic findings of unknown significance with the potential to change a patient’s management when left to physician discretion. It is conceivable that bias may have influenced treatment decisions in this unblinded study thereby overinflating the need for treatment intensification. One could argue that important arrhythmia detection resulting in the provision of life-prolonging interventions (i.e., anticoagulation for sustained AF and implantation of a defibrillator) occurred in a small portion of the study cohort (5 of 103). Additionally, although 10% of patients required permanent pacing at 1 year, important information on the 9 patients with HAVB requiring a pacemaker, 5 of whom were asymptomatic, is absent, including whether the HAVB may be related to increased vagal tone, the duration and presence of recurrent HAVB episodes, and the rate of the escape rhythm and presence of pauses.
Although ILRs are easy to insert and provide long-term monitoring that is convenient for patients, considerations on the consequences of inappropriate treatment decisions/overtreatment in addition to the societal financial cost with widespread use of ILRs in this patient population are very important. A study where physicians are randomized to receive and incorporate data from ILRs in the care of post-TAVR patients is necessary before drawing the conclusion of the authors that ILRs are needed for “expediting the initiation of treatment” in post-TAVR patients.
Please note: The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2018 American College of Cardiology Foundation
- Rodés-Cabau J.,
- Urena M.,
- Nombela-Franco L.,
- et al.