As transcatheter aortic valve implantation (TAVI) becomes the gold standard for treating aortic stenosis across a growing range of patient risk categories, new challenges are emerging—chief among them, conduction disturbances.

Despite procedural success, atrioventricular (AV) block, new-onset left bundle branch block (LBBB), and high-degree heart block remain common complications after TAVI. These electrical disruptions can impact long-term patient outcomes, mandate permanent pacemaker implantation (PPI), and even affect mortality.

In this blog, we unpack the why, who, and when of post-TAVI conduction issues—and how a thoughtful approach to monitoring and pacing can improve care.

Why Do Conduction Disturbances Occur After TAVI?

The aortic valve annulus lies in close proximity to the His-Purkinje conduction system, particularly along the membranous septum. Mechanical stress, radial force, and local trauma during valve implantation can easily disrupt electrical conduction, especially with:

• Deep valve implantation
• Over-sizing of the prosthesis
• Pre-existing conduction abnormalities
• Anatomical variations (e.g. short membranous septum, bulky calcium)

Incidence and Clinical Relevance

• New-onset LBBB: ~25–30% after self-expanding valves; ~10–15% with balloon-expandable systems
• High-degree AV block: ~10–15%
• Permanent pacemaker implantation: 8–25%, depending on device type and patient anatomy

While many disturbances resolve spontaneously, some persist—and inappropriately timed pacemaker decisions may lead to unnecessary device implantation or sudden deterioration.

Key Risk Factors for Post-TAVI Conduction Disturbance

Clinical Tip: Patients with RBBB and baseline prolonged PR interval are at the highest risk for complete heart block post-TAVI.

Post-TAVI Monitoring Strategy

A structured monitoring plan is essential to guide appropriate pacing decisions.

In-Hospital Monitoring (Day 0–3)

• Continuous telemetry
• 12-lead ECG daily
• QRS and PR interval tracking

If LBBB develops, monitor for QRS widening and symptoms of AV block.

🔬 High-Risk Indicators During Monitoring:

• Alternating bundle branch block
• Progressive PR/QRS prolongation
• Transient high-grade AV block
• Pause >3 seconds or symptomatic bradycardia

When Should You Implant a Permanent Pacemaker?

Clear Indications (Implant Immediately):

• Persistent high-grade AV block (Mobitz II or complete)
• Symptomatic bradycardia with hemodynamic instability
• Alternating bundle branch block + pause/syncope

Watchful Waiting (With Close Monitoring):

• New-onset LBBB without symptoms
• Intermittent conduction abnormalities
• Junctional rhythm without AV dissociation

Suggested Observation Period: 48–72 hours post-TAVI for borderline cases; consider ambulatory Holter or ILR if early discharge is planned.

Valve Type and Pacing Risk

Implantation depth matters more than valve type alone. Deep placement (≥6 mm below annulus) significantly increases conduction risk.

Long-Term Implications of Post-TAVI Pacing

While pacemakers prevent bradyarrhythmic complications, they are not benign. Chronic RV pacing has been associated with:

• Worsened LV function
• Higher heart failure rehospitalization
• Reduced long-term survival

This underscores the need to avoid unnecessary implantation and consider alternatives such as His-bundle or biventricular pacing in select patients.

Final Thought: Balance Speed with Strategy

TAVI teams must walk a fine line between reacting to early conduction changes and premature pacemaker implantation.

The key is structured monitoring, individualized risk assessment, and clear pacing algorithms.

At TriVasc Academy, we emphasize a team-based, evidence-informed approach to conduction management—because saving a heart valve means little if we destabilize the heart’s rhythm in the process.

Coming Soon at TriVasc Academy:
Post-TAVI conduction monitoring checklists
Pacemaker implantation decision trees
Annotated ECGs and real-world case series