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Updated: Jan 7, 2026
06:04
Upper-extremity Approach for Secondary Access in Transfemoral Transcatheter Aortic Valve Implantation
Published on: August 8, 2025
473
Mechanisms Underlying Alterations in Cardiac Conduction After Transcatheter Aortic Valve Replacement.
Jonathan W Waks1, Marie-France Poulin1, John-Ross D Clarke1,2
1Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
JAMA Cardiology
|December 10, 2025
Summary
Transcatheter aortic valve replacement (TAVR) can cause heart block. This study found that intraprocedural and delayed heart block have different causes and predictors, aiding in better patient management.
Area of Science:
- Cardiology
- Electrophysiology
- Interventional Cardiology
Background:
- Transcatheter aortic valve replacement (TAVR) is a common treatment for aortic stenosis.
- Heart block requiring pacemaker implantation complicates at least 10% of TAVR procedures.
- Understanding the mechanisms of heart block post-TAVR is crucial for improving patient outcomes.
Purpose of the Study:
- To investigate the mechanisms underlying heart block after TAVR.
- To identify predictors of intraprocedural and delayed heart block following TAVR.
- To differentiate between AV nodal and infranodal block mechanisms.
Main Methods:
- A prospective cohort study of 409 patients undergoing TAVR without pre-existing pacemakers.
- Continuous electrocardiogram (ECG) and His bundle recording during TAVR by an electrophysiologist.
- Electrophysiologic studies performed pre- and post-TAVR, with 1-year follow-up.
Main Results:
- 9.7% of patients developed heart block requiring pacemaker implantation.
- Intraprocedural block was predicted by pre-existing right bundle-branch block (RBBB).
- Delayed heart block predictors included prolonged His-ventricular interval, PR interval, and AV Wenckebach cycle length.
Conclusions:
- Mechanisms of heart block during and after TAVR differ significantly.
- Both AV nodal and infranodal block contribute to heart block post-TAVR.
- Identifying specific predictors can improve risk stratification and management of TAVR-related heart block.
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