Non-invasive predictors for infranodal conduction delay in patients with left bundle branch block after TAVR

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Left bundle branch block (LBBB) is a common complication after Transcatheter Aortic Valve Replacement (TAVR).
• LBBB increases the risk of atrioventricular (AV) block, necessitating further investigation into conduction delays.
• Identifying predictors for infranodal conduction delay is crucial for patient management post-TAVR.

Purpose of the Study:

• To identify non-invasive predictors of infranodal conduction delay in patients with LBBB following TAVR.
• To evaluate the association between electrocardiographic parameters and His-ventricular (HV) interval prolongation.

Main Methods:

• Analysis of consecutive patients undergoing TAVR with LBBB (pre-existing or new-onset).
• Measurement of His-ventricular (HV) interval on day 1 post-TAVR; infranodal conduction delay defined as HV interval > 55 ms.
• Inclusion of baseline, procedural, and electrocardiographic parameters, including surface and intracardiac ECG.

Main Results:

• Infranodal conduction delay was observed in 25% of 151 included patients.
• Longer post-TAVR PR and QRS durations, and a greater PR interval change (ΔPR), were associated with HV prolongation.
• In sinus rhythm patients, ΔPR was the sole independent predictor of infranodal conduction delay (OR per 10 ms increase: 1.52; p=0.002).

Conclusions:

• A ΔPR < 20 ms predicts the absence of infranodal conduction delay in post-TAVR patients with LBBB.
• Surface ECG analysis, specifically ΔPR, offers a simple, non-invasive tool for risk stratification.
• This finding aids in identifying patients who may not require further invasive electrophysiological study.