The American College of Cardiology (ACC) has released a new Expert Consensus Decision Pathway (ECDP) on the management of conduction disturbances after transcatheter aortic valve replacement (TAVR).
The document provides guidance to clinicians in identifying and managing this common complication of TAVR, covering the pre-TAVR, peri-procedural and post-TAVR periods.
“Conduction disturbances after TAVR are common and there is currently heterogeneity in how they’re managed, ranging from a casual observational approach to invasive electrophysiological studies and preemptive pacemaker implantation,” said writing committee chair Scott Lilly, MD, PhD, from Ohio State Wexner Medical Center in Columbus, Ohio.
“We felt this kind of collaborative effort to review what little research there is on this topic and come to [an] expert consensus was long overdue,” he added.
The document was published online October 21 in the Journal of the American College of Cardiology.
Lilly stressed in an interview that this effort is an ECDP and not a guideline, “because there is not data out there to solidly stand on and say, ‘this is the way we should do things.’ “
His hope is that this document will generate more discussion on this topic and spur some (probably National Institutes of Health-sponsored) clinical trials to better guide practice.
Not Uncommon and Not Decreasing
Complete heart block requiring permanent pacemaker (PPM) implantation is seen in about 15% of patients within 30 days after TAVR. While this is a clear indication for PPM, there is no consensus on the management of less severe conduction disturbances such as new bundle branch or transient complete atrioventricular (AV) heart block.
Unlike the rates of bleeding, vascular injury, and stroke, which have decreased over time, the rates of in-hospital PPM implantation after TAVR have not changed significantly since commercialization in 2012. This is a concern as TAVR is increasingly used in younger, lower-risk patients.
“The pacemaker rate really hasn’t improved at a clip we would like to see if it was going to be a durable technology,” Lilly said.
Consensus regarding a reasonable strategy to manage cardiac conduction disturbances after TAVR has been elusive. This is a result of several things: a dearth of adequately powered, randomized controlled trials; the often transient nature of the conduction disturbances; evolving technologies; and the interplay of cardiology subspecialties involved.
The 2013 European Society of Cardiology guidelines address pacing post-TAVR, but do not provide in-depth discussion on the topic. This is the first effort sponsored by a cardiovascular society in the United States to review the existing data and experience and proposed evidence-based expert guidance.
Pre-TAVR assessment should consider the patient’s risk for post-procedure conduction disturbances, the authors say. Since bradyarrythmias and aortic stenosis may present similarly (fatigue, lightheadedness, and syncope being hallmarks of both), a careful history is needed to determine if bradyarrhythmia is present.
An electrocardiogram (ECG) or ambulatory rhythm monitoring may identify baseline conduction abnormalities and help predict the need for post-TAVR PPM.
“In this section, we underscored some of the literature that has raised awareness about the presence of preexisting arrhythmias in TAVR patients and suggest that monitoring in selected patients before the procedure is reasonable, particularly those presenting with syncope or lightheadedness,” said Lilly.
On the day of the procedure, patients determined to have elevated risk for complete AV heart block require careful perioperative ECG and hemodynamic monitoring. Regardless of preexisting risk, all patients, say the authors, should be monitored on a telemetry unit during the procedure with ability to do emergency pacing if necessary.
“In the peri-procedural section, we address the role of electrophysiological studies for identifying patients at high-risk of subsequent heart block,” said Lilly. “That’s a practice that’s occurring at a number of centers, but the data out there is insufficient to establish it as a pacemaker indication. Routine EP testing for patients deemed at risk for conduction disturbances after TAVR is not guideline-based and more research is needed.”
The document also outlines the effects of medications and anesthesia on post-procedure conduction abnormalities.
The authors define post-TAVR management as continuing through 30-days post-discharge.
The ECDP carefully outlines which patients can be discharged without monitoring and those for whom outpatient monitoring can be considered.
“If I’m going to pick one thing from this section, it’s the monitoring piece. A lot of patients that have a conduction disturbance right after TAVR — but you’re not sure if it’s going to progress and require a pacemaker — might stay in the hospital for an extended time waiting to see if the heart holds up,” reported Lilly.
“But a number of centers are now discharging people at 1 or 2 days, which begs the question: What do you do with these folks? Our group has published data showing that 30-day monitoring in select patients is a safe approach,” said Lilly.
There are shortcomings, however, in existing data, and recommendations will likely change as more data are collected, he explained.
As well, there remains uncertainty in how conduction block should be managed after TAVR, and clinical judgement is “foundational” in this, write the authors.
“This document is meant to help programs deal with these situations right now, acknowledging full and well, that really good randomized clinical data is not available,” said Lilly.
Lilly has disclosed no relevant financial relationships. The work of the writing committee was supported exclusively by the American College of Cardiology without commercial support.
J Am Coll Cardiol. Published online October 21, 2020. Full text