Risk Stratification of New Persistent Left Bundle Branch Block After Transcatheter Aortic Valve Implantation

Area of Science:

• Cardiology
• Interventional Cardiology
• Cardiac Electrophysiology

Background:

• New-onset persistent left bundle branch block (NOP-LBBB) after transcatheter aortic valve implantation (TAVI) is associated with adverse outcomes.
• Previous studies may be confounded by pre-existing or post-procedural permanent pacemaker (PPM) implantation.
• Long-term outcomes and risk stratification for NOP-LBBB without PPM are not well-established.

Purpose of the Study:

• To investigate the long-term outcomes of NOP-LBBB in patients undergoing TAVI without PPM implantation before or after the procedure.
• To identify risk factors and stratify patients with NOP-LBBB based on pre-TAVI left ventricular ejection fraction (LVEF).

Main Methods:

• International, multicenter, retrospective study including 2,240 patients who underwent TAVI.
• Analysis of outcomes in patients who developed NOP-LBBB, stratified by pre-TAVI LVEF (<40% vs >40%).
• Assessment of cardiac mortality, heart failure readmission, and changes in LVEF post-TAVI.

Main Results:

• NOP-LBBB developed in 17.5% of patients and was associated with increased cardiac mortality (aHR 1.419) and composite outcomes of cardiac mortality/heart failure readmission (aHR 1.313).
• Patients with NOP-LBBB and pre-TAVI LVEF <40% had significantly higher risks of cardiac mortality (aHR 2.049), heart failure (aHR 3.990), and composite outcomes (aHR 2.729).
• NOP-LBBB with pre-TAVI LVEF <40% showed a trend towards improved LVEF post-TAVI, while NOP-LBBB with LVEF >40% showed a decrease.

Conclusions:

• NOP-LBBB in TAVI patients without PPM is associated with worse long-term outcomes, especially in those with pre-existing low LVEF.
• Risk stratification based on pre-TAVI LVEF is crucial for patients developing NOP-LBBB post-TAVI.
• Further prospective studies are warranted to confirm these findings and guide clinical management.