Conduction disturbance at TAVI in a woman with right bundle branch block — case discussion

Objectives

1. Use the ESC 2021 TAVI conduction predictors in procedural planning, and know when prophylactic pacing is not indicated.^[1]
2. Apply the ESC 2021 rows for conduction disturbances after TAVI, and contrast ACC/AHA/HRS 2018.^[1][4]
3. Programme the device to limit unnecessary ventricular pacing after TAVI.^[1]

Candidate brief

Practice case discussion; this is not a real patient. You are the cardiologist in the TAVI team. In 15 minutes, discuss her conduction risk before the procedure, your plan after the intraprocedural block, and how you would set up and follow any device.

Expected actions

• Plan for the risk. ESC 2021: predictors of permanent pacing, especially RBBB, the most consistent and powerful predictor, should be incorporated into procedural planning, including transcatheter valve selection, implantation height and balloon inflations.^[1] Procedural predictors in ESC 2021 Table 10 include a self-expandable valve and deeper valve implantation.^[1]
• No prophylactic pacemaker. Prophylactic permanent pacemaker implantation is not indicated before TAVI in patients with RBBB and no indication for permanent pacing (ESC 2021 Class III, Level C).^[1] Electrophysiology consultation before the procedure is needed for patients with pre-existing advanced conduction system disease who may have an indication for permanent pacing irrespective of the TAVI procedure; she has no such indication.^[1]
• Recognise the row she now meets. ESC 2021: early permanent pacing (immediately after the procedure or within 24 h) should be considered in patients with pre-existing RBBB who develop any further conduction disturbance during or after TAVI, defined as transient high-degree AVB, PR prolongation or QRS axis change (Class IIa, Level B).^[1] She has two of these disturbances: transient high-degree AVB and PR prolongation from 180 to 230 ms.^[1] Her PR has also lengthened by more than 20 ms on a pre-existing conduction abnormality: ESC 2021 says ambulatory continuous ECG monitoring (implantable or external, for 7–30 days) or EPS (performed 3 days or more after TAVI; HV of 70 ms or more may be considered positive for permanent pacing) may be considered for a pre-existing conduction abnormality with QRS or PR prolongation over 20 ms and no further prolongation during 48-h observation (Class IIb, Level C); the early-pacing row has the higher class (IIa, B).^[1]
• Decide together. ESC 2021 recommends basing the decision on the best available evidence, individual risks and benefits, the patient's preferences and goals of care, using shared decision-making (Class I, Level C).^[1]
• Limit ventricular pacing. Rates of permanent pacing after TAVI range from 3.4% to 25.9% in randomised trials and large registries, and RV pacing may lead to deterioration in LV function, so efforts to minimise unnecessary permanent pacing are warranted.^[1] Given the low rates of long-term pacing dependency, algorithms promoting spontaneous AV conduction should be used.^[1] HRS/APHRS/LAHRS 2023 found insufficient data to recommend a device type after TAVI beyond its recommendations for AV block or LBBB in other settings.^[5]
• Contrast ACC/AHA/HRS 2018. It recommends permanent pacing before discharge for new AV block after transcatheter aortic valve replacement that is associated with symptoms or haemodynamic instability and does not resolve (COR I, LOE B-NR); her block resolved, so this row does not apply.^[4] Its other rows concern new persistent BBB after the procedure: careful surveillance for bradycardia is reasonable (COR IIa, LOE B-NR), and a permanent pacemaker may be considered for new persistent LBBB (COR IIb, LOE B-NR).^[4]
• Follow-up. If she has a pacemaker, ESC 2021 says remote device management should be considered to provide earlier detection of clinical problems or technical issues (Class IIa, Level B), and with remote device management, in-office routine follow-up of single- and dual-chamber pacemakers may be spaced by up to 24 months (Class IIa, Level A).^[1] Remote device management is recommended to reduce in-office follow-ups in pacemaker patients who have difficulty attending in-office visits (e.g. due to reduced mobility or other commitments) or by patient preference (Class I, Level A).^[1]

If the course had been different

• Persistent block. If complete or high-degree AVB had persisted for 24–48 h after TAVI, permanent pacing would be recommended (ESC 2021 Class I, Level B); new-onset alternating BBB after TAVI is also a Class I indication (Level C).^[1]
• New LBBB instead. New-onset LBBB is the most frequent conduction abnormality after TAVI, and only a small minority of these patients need a pacemaker.^[1] For new LBBB with QRS over 150 ms or PR over 240 ms and no further prolongation during the more than 48 h after TAVI, ambulatory continuous ECG monitoring (implantable or external, 7–30 days) or an EPS (performed 3 days or more after TAVI; HV of 70 ms or more may be considered positive for permanent pacing) should be considered (ESC 2021 Class IIa, Level C).^[1] New-onset LBBB with QRS below 150 ms may not require further evaluation during hospitalisation.^[1] Separately, ESC 2021 Figure 12 has a box for persistent new LBBB with QRS over 150 ms or PR over 240 ms with no further prolongation during more than 48 h after the procedure.^[1] A footnote to that box lists high-risk parameters for high-degree AV block in new-onset LBBB: AF, a prolonged PR interval and LVEF below 40%.^[1]
• Dynamic progression. ESC 2021 identifies several high-risk subgroups of patients with new LBBB. In such patients with dynamic progression after TAVI (new BBB with dynamic prolongation of QRS and/or PR), an extended in-hospital monitoring period of up to 5 days should be considered.^[1]
• No new disturbance. Patients without new conduction disturbances after TAVI are at very low risk of developing high-degree AVB.^[1]

Marking

Pass:

• Uses RBBB and procedural predictors in planning and does not implant a prophylactic pacemaker for RBBB alone.^[1]
• Identifies the ESC 2021 Class IIa, Level B row for pre-existing RBBB with a further conduction disturbance, and its timing (immediately or within 24 h).^[1]
• Names the Class IIb, Level C alternative (ambulatory continuous ECG monitoring for 7–30 days, or EPS 3 days or more after TAVI) for a pre-existing conduction abnormality with PR prolongation over 20 ms and no further prolongation during 48-h observation.^[1]
• Programmes algorithms that promote spontaneous AV conduction.^[1]
• Separates the ACC/AHA/HRS 2018 Class I row (unresolved AV block with symptoms or instability) from her situation.^[4]

Fail:

• Implants a pacemaker before TAVI for RBBB alone.^[1]
• Misses the pre-existing RBBB row and waits days for observation without considering early pacing.^[1]
• Blends ESC and ACC/AHA/HRS rows into one recommendation.