Trends in the occurrence of new conduction abnormalities after transcatheter aortic valve implantation

Predictors, clinical impact, and management strategies for conduction abnormalities after transcatheter aortic valve replacement: an updated review

Transcatheter aortic valve replacement (TAVR) has increasingly become a safe, feasible, and widely accepted alternative surgical treatment for patients with severe symptomatic aortic stenosis. However, the incidence of conduction abnormalities associated with TAVR, including left bundle branch block (LBBB) and high-degree atrioventricular block (HAVB), remains high and is often correlated with risk factors such as the severity of valvular calcification, preexisting conditions in patients, and procedural factors. The existing research results on the impact of post-TAVR conduction abnormalities and permanent pacemaker (PPM) requirements on prognosis, including all-cause mortality and rehospitalization, remain contradictory, with varied management strategies for post-TAVR conduction system diseases across different institutions. This review integrates the latest research in the field, offering a comprehensive discussion of the mechanisms, risk factors, consequences, and management of post-TAVR conduction abnormalities. This study provides insights into optimizing patient prognosis and explores the potential of novel strategies, such as conduction system pacing, to minimize the risk of adverse clinical outcomes.

Impact of the use of cusp-overlap projection on the incidence of permanent pacemaker implantation post-transcatheter aortic valve implantation with self-expanding valves

INTRODUCTION

Current rates of permanent pacemaker implantation (PPMI) after transcatheter aortic valve implantation (TAVI) range between 3.4% and 25.9%. PPMI is associated with a worse prognosis. A lower valve implantation depth is associated with an increased risk of conduction disturbances. Theoretically, cusp-overlap projection (COP) has the potential to enable higher valve deployment.

OBJECTIVE

To compare the 30-day PPMI incidence post-TAVI using self-expanding valves according to the fluoroscopic guidance technique.

METHODS

This retrospective single-center study assessed consecutive patients undergoing TAVI with CoreValve™ valves between April 2019 and November 2021, grouped according to the fluoroscopic guidance technique (COP vs. coplanar implantation technique [CIT]).

RESULTS

A total of 122 patients were included, predominantly women (52.5%), with a mean age of 81.6±5.5 years. COP was used in 49.2% of the sample. The CIT group had a significantly higher prevalence of previous beta-blocker use (p<0.01), lower baseline left ventricular ejection fraction (p=0.04) and a higher EuroSCORE II (p=0.02). The 30-day PPMI rate was 27.9% (n=34), with no significant difference between the COP and CIT groups (26.7% vs. 29.0%, p=0.77). Complete atrioventricular block was the main cause (38.5%). Likewise, mean fluoroscopy time (p=0.14) and contrast volume (p=0.35) used were similar between the two groups. Radiation dose was lower in the COP group (p=0.02). There was no significant difference between post-TAVI grades III and IV aortic valve regurgitation (p=0.27) and there were no cases of periprocedural acute coronary occlusion.

CONCLUSIONS

This study shows that the COP technique, although safe and not associated with increased complexity, did not significantly reduce the 30-day PPMI rate compared to the traditional CIT view.

Latest Developments in Adapting Deep Learning for Assessing TAVR Procedures and Outcomes

Aortic valve defects are among the most prevalent clinical conditions. A severely damaged or non-functioning aortic valve is commonly replaced with a bioprosthetic heart valve (BHV) via the transcatheter aortic valve replacement (TAVR) procedure. Accurate pre-operative planning is crucial for a successful TAVR outcome. Assessment of computational fluid dynamics (CFD), finite element analysis (FEA), and fluid-solid interaction (FSI) analysis offer a solution that has been increasingly utilized to evaluate BHV mechanics and dynamics. However, the high computational costs and the complex operation of computational modeling hinder its application. Recent advancements in the deep learning (DL) domain can offer a real-time surrogate that can render hemodynamic parameters in a few seconds, thus guiding clinicians to select the optimal treatment option. Herein, we provide a comprehensive review of classical computational modeling approaches, medical imaging, and DL approaches for planning and outcome assessment of TAVR. Particularly, we focus on DL approaches in previous studies, highlighting the utilized datasets, deployed DL models, and achieved results. We emphasize the critical challenges and recommend several future directions for innovative researchers to tackle. Finally, an end-to-end smart DL framework is outlined for real-time assessment and recommendation of the best BHV design for TAVR. Ultimately, deploying such a framework in future studies will support clinicians in minimizing risks during TAVR therapy planning and will help in improving patient care.

Transcatheter Aortic Valve Implantation: Addressing the Subsequent Risk of Permanent Pacemaker Implantation

Transcatheter aortic valve implantation (TAVI) is now a commonly used therapy in patients with severe aortic stenosis, even in those patients at low surgical risk. The indications for TAVI have broadened as the therapy has proven to be safe and effective. Most challenges associated with TAVI after its initial introduction have been impressively reduced; however, the possible need for post-TAVI permanent pacemaker implantation (PPI) secondary to conduction disturbances continues to be on the radar. Conduction abnormalities post-TAVI are always of concern given that the aortic valve lies in close proximity to critical components of the cardiac conduction system. This review will present a summary of noteworthy pre-and post-procedural conduction blocks, the best use of telemetry and ambulatory device monitoring to avoid unnecessary PPI or to recognize the need for late PPI due to delayed high-grade conduction blocks, predictors to identify those patients at greatest risk of requiring PPI, important CT measurements and considerations to optimize TAVI planning, and the utility of the MInimizing Depth According to the membranous Septum (MIDAS) technique and the cusp-overlap technique. It is stressed that careful membranous septal (MS) length measurement by MDCT during pre-TAVI planning is necessary to establish the optimal implantation depth before the procedure to reduce the risk of compression of the MS and consequent damage to the cardiac conduction system.

Patient-specific multi-scale design optimization of transcatheter aortic valve stents

BACKGROUND AND OBJECTIVE

Transcatheter aortic valve implantation (TAVI) has become the standard treatment for a wide range of patients with aortic stenosis. Although some of the TAVI post-operative complications are addressed in newer designs, other complications and lack of long-term and durability data on the performance of these prostheses are limiting this procedure from becoming the standard for heart valve replacements. The design optimization of these devices with the finite element and optimization techniques can help increase their performance quality and reduce the risk of malfunctioning. Most performance metrics of these prostheses are morphology-dependent, and the design and the selection of the device before implantation should be planned for each individual patient.

METHODS

In this study, a patient-specific aortic root geometry was utilized for the crimping and implantation simulation of 50 stent samples. The results of simulations were then evaluated and used for developing regression models. The strut width and thickness, the number of cells and patterns, the size of stent cells, and the diameter profile of the stent were optimized with two sets of optimization processes. The objective functions included the maximum crimping strain, radial strength, anchorage area, and the eccentricity of the stent.

RESULTS

The optimization process was successful in finding optimal models with up to 40% decrease in the maximum crimping strain, 261% increase in the radial strength, 67% reduction in the eccentricity, and about an eightfold increase in the anchorage area compared to the reference device.

CONCLUSIONS

The stents with larger distal diameters perform better in the selected objective functions. They provide better anchorage in the aortic root resulting in a smaller gap between the device and the surrounding tissue and smaller contact pressure. This framework can be used in designing patient-specific stents and improving the performance of these devices and the outcome of the implantation process.

Occurrence and Persistency of Conduction Disturbances during Transcatheter Aortic Valve Implantation

Background and Objectives: Conduction disturbances such as left bundle branch block (LBBB) and complete atrio-ventricular block (cAVB) are relatively frequent complications following trans-catheter aortic valve implantation (TAVI). We investigated the dynamics of these conduction blocks to further understand luxating factors and predictors for their persistency. Materials and Methods: We prospectively included 157 consecutive patients who underwent a TAVI procedure. Electrocardiograms (ECGs) were obtained at specific time points during the TAVI procedure and at follow-up until at least six months post-procedure. Results: Of the 106 patients with a narrow QRS complex (nQRS) before TAVI, ~70% developed LBBB; 28 (26.4%) being classified as super-transient (ST-LBBB), 20 (18.9%) as transient (T-LBBB) and 24 (22.6%) as persistent (P-LBBB). Risk of LBBB was higher for self-expandable (SE) than for balloon-expandable (BE) prostheses and increased with larger implant depth. During the TAVI procedure conduction disturbances showed a dynamic behavior, as illustrated by alternating kinds of blocks in 18 cases. Most LBBBs developed during balloon aortic valvuloplasty (BAV) and at positioning and deployment of the TAVI prosthesis. The incidence of LBBB was not significantly different between patients who did and did not undergo BAV prior to TAVI implantation (65.3% and 74.2%, respectively (p = 0.494)). Progression to cAVB was most frequent for patients with preexisting conduction abnormalities (5/34) patients) and in patients showing ST-LBBB (6/28). Conclusions: During the TAVI procedure, conduction disturbances showed a dynamic behavior with alternating types of block in 18 cases. After a dynamic period of often alternating types of block, most BBBs are reversible while one third persist. Patients with ST-LBBB are most prone to progressing into cAVB. The observation that the incidence of developing LBBB after TAVI is similar with and without BAV suggests that a subgroup of patients has a substrate to develop LBBB regardless of the procedure.

Conduction Disturbances and Permanent Pacemaker Implantation after Transcatheter Aortic Valve Replacement: Predictors and Prevention

Conduction disturbances and permanent pacemaker implantation (PPMI) remain a frequent and important consequence of transcatheter aortic valve replacement (TAVR). Understanding risk factors for TAVR-related conduction disturbances could improve patient selection, procedural techniques, and peri-procedural efforts for monitoring and treatment of heart block. Several studies have identified patient-related and procedural factors associated with new-onset left bundle branch block, high-degree atrioventricular block, and the need for PPMI after TAVR. Notable patient-related predictors include pre-existing right bundle branch block, membranous septal length, and calcification of the left ventricular outflow tract. Modifiable procedural predictors include device implantation depth, prosthesis oversizing, and valve type. This review aims to summarize the current literature examining predictors of conduction disturbances and PPMI after TAVR, particularly with regard to the newer-generation valve types. We also propose a management algorithm for the management of conduction disturbances post-procedure.

Effective Distance between Aortic Valve and Conduction System Is an Independent Predictor of Persistent Left Bundle Branch Block during Transcatheter Aortic Valve Implantation

Background and objectives: Persistent left bundle branch block (P-LBBB) has been associated with poor clinical outcomes of transcatheter aortic valve implantation (TAVI) procedures. We hypothesized that the distance from the aortic valve to the proximal conduction system, expressed as the effective distance between the aortic valve and conduction system (EDACS), can predict the occurrence of P-LBBB in patients undergoing a TAVI procedure. Materials and methods: In a retrospective study, data from 269 patients were analyzed. EDACS was determined using two longitudinal CT sections. Results: Sixty-four of the patients developed P-LBBB. EDACS ranged between −3 and +18 mm. EDACS was significantly smaller in P-LBBB than in non-P-LBBB patients (4.6 (2.2–7.1) vs. 8.0 (5.8–10.2) mm, median values (interquartile range); p < 0.05). Receiver operating characteristic analysis showed an area under the curve of 0.78 for predicting P-LBBB based on EDACS. In patients with EDACS of ≤3 mm and >10 mm, the chance of developing P-LBBB was ≥50% and <10%, respectively. Conclusions: A small EDACS increases the risk for the development of P-LBBB during TAVI by a factor of >25. As EDACS can be measured pre-procedurally, it may be a valuable additional factor to weigh the risks of transcatheter and surgical aortic valve replacement.

Long Term Outcomes of Patients Treated With Transcatheter Aortic Valve Implantation

Transcatheter aortic-valve implantation (TAVI) is an established treatment option in patients with severe symptomatic aortic stenosis. Intermediate and long-term follow up data of these patients is limited. Data was taken from a large all-comer single center prospective registry (2008 to 2019). The primary end point was all-cause mortality. The secondary endpoints were long-term valve hemodynamic performance; paravalvular leak (PVL) at 5-year follow-up. We also report on temporal trends in this cohort. Our cohort included 998 patients with a mean age of 82.3 ± 7.2 years and 52.2% females. TAVI was performed via the transfemoral, trans-apical, subclavian and other access routes in 93.9%, 3.6%, 2.5%, and 0.6% of patients, respectively. A self-expandable device was used in 69.4% of cases, balloon expandable device in 28.1% and in 2.5% other devices. The cumulative risk for all-cause mortality at 5 years was 43.4% (95% CI 39.1 to 47.7). The immediate and long-term valve gradients were low and maintained. On durability analysis at 5 years, severe structural valve deterioration was present in 1.6% of cases. At 5-year follow-up, PVL was moderate in 3.3% and no patients has severe PVL. On temporal trends analysis, we found that the procedural aspects of TAVI improved over time with lower rates of significant PVL and significantly lower procedural mortality. In conclusion, TAVI patients have a favorable long-term outcome, with excellent valve hemodynamic parameters and good clinical outcomes. Over time and with increasing experience, procedural and patient outcomes have improved.

Predictors of pacemaker implantation after transcatheter aortic valve implantation according to kind of prosthesis and risk profile: a systematic review and contemporary meta-analysis

AIMS

Permanent pacemaker implantation (PPI) may be required after transcatheter aortic valve implantation (TAVI). Evidence on PPI prediction has largely been gathered from high-risk patients receiving first-generation valve implants. We undertook a meta-analysis of the existing literature to examine the incidence and predictors of PPI after TAVI according to generation of valve, valve type, and surgical risk.

METHODS AND RESULTS

We made a systematic literature search for studies with ≥100 patients reporting the incidence and adjusted predictors of PPI after TAVI. Subgroup analyses examined these features according to generation of valve, specific valve type, and surgical risk. We obtained data from 43 studies, encompassing 29 113 patients. Permanent pacemaker implantation rates ranged from 6.7% to 39.2% in individual studies with a pooled incidence of 19% (95% CI 16-21). Independent predictors for PPI were age [odds ratio (OR) 1.05, 95% confidence interval (CI) 1.01-1.09], left bundle branch block (LBBB) (OR 1.45, 95% CI 1.12-1.77), right bundle branch block (RBBB) (OR 4.15, 95% CI 3.23-4.88), implantation depth (OR 1.18, 95% CI 1.11-1.26), and self-expanding valve prosthesis (OR 2.99, 95% CI 1.39-4.59). Among subgroups analysed according to valve type, valve generation and surgical risk, independent predictors were RBBB, self-expanding valve type, first-degree atrioventricular block, and implantation depth.

CONCLUSIONS

The principle independent predictors for PPI following TAVI are age, RBBB, LBBB, self-expanding valve type, and valve implantation depth. These characteristics should be taken into account in pre-procedural assessment to reduce PPI rates. PROSPERO ID CRD42020164043.

Fusion imaging of pre- and post-procedural computed tomography angiography in transcatheter aortic valve implantation patients: evaluation of prosthesis position and its influence on new conduction disturbances

AIMS

The purpose of this study was to evaluate prosthesis position by fusion of pre- and post-transcatheter aortic valve implantation (TAVI) computed tomography angiography (CTA) images and to investigate its influence on the occurrence of new conduction disturbances (CD).

METHODS AND RESULTS

We performed CTA fusion imaging in 120 TAVI patients (Edwards Sapien 3) on a standard image post-processing workstation to obtain a 3D reconstruction of the transcatheter heart valve (THV) position within the native annulus region. Optimal implantation depth of the THV was defined according to the manufacturers recommendations as 70-80% of the prosthesis above (aortic) and 20-30% below (ventricular) the native annulus plane. Pre- and post-interventional electrocardiograms (ECGs) were assessed for the development of new CD. THV position was found to be within, above, or below the prespecified margins in 32 patients (27%), 71 patients (59%), and 17 patients (14%), respectively. Interobserver reliability was high for fusion measurements [e.g. median THV position 0.983, 95% confidence interval (CI): 0.935-0.996]. Patients with low stent position were significantly more likely to develop new CD compared with patients with optimal or high stent position (P = 0.039). Independent predictors of CD in multivariate analysis were low THV position [odds ratio (CI): 1.362 (1.093-1.698), P = 0.006] and calcification of the device landing zone [odds ratio (CI): 1.149 (1.024-1.289), P = 0.018].

CONCLUSION

Fusion imaging of pre- and post-TAVI-CTA allows for the exact evaluation of THV position in relation to the native annulus plane. A low THV position as assessed by fusion imaging is associated with the development of new CD post-TAVI.

Effect of new and persistent left bundle branch block after transcatheter aortic valve replacement on long-term need for pacemaker implantation

Cardiac conduction abnormalities, including left bundle branch block (LBBB), are common following transcatheter aortic valve replacement (TAVR). This study assessed the incidence and outcomes of new or widening persistent LBBB following TAVR. Data regarding 550 consecutive patients undergoing TAVR between 2012 and 2016 at our institution were retrospectively reviewed. Both 30-day and 1-year outcomes of patients with isolated new or worsening LBBB following TAVR were reviewed. Fifty-two patients (9.5%) developed new or worsening LBBB. Six of the 52 (11.5%) patients received a permanent pacemaker (PPM) for LBBB prior to discharge. For patients discharged home following TAVR without a PPM, the 1-year PPM requirement was 15.2% in patients with new or worsening LBBB compared to 4.5% in patients without new or worsening LBBB (P = 0.01). One-year mortality rates for patients who did not have a new PPM placed before discharge were 15.2% in patients with new or worsening LBBB, 13.9% in patients without new or worsening LBBB, and 11.9% in patients with preoperative PPMs (P = 0.81). Patients with new or worsening persistent LBBB discharged without a PPM experience a higher requirement for PPM implantation in the year following TAVR compared to patients without new or worsening persistent LBBB.

The Impact of Size and Position of a Mechanical Expandable Transcatheter Aortic Valve: Novel Insights Through Computational Modelling and Simulation

Transcatheter aortic valve implantation has become an established procedure to treat severe aortic stenosis. Correct device sizing/positioning is crucial for optimal outcome. Lotus valve sizing is based upon multiple aortic root dimensions. Hence, it often occurs that two valve sizes can be selected. In this study, patient-specific computer simulation is adopted to evaluate the influence of Lotus size/position on paravalvular aortic regurgitation (AR) and conduction abnormalities, in patients with equivocal aortic root dimensions. First, simulation was performed in 62 patients to validate the model in terms of predicted AR and conduction abnormalities using postoperative echocardiographic, angiographic and ECG-based data. Then, two Lotus sizes were simulated at two positions in patients with equivocal aortic root dimensions. Large valve size and deep position were associated with higher contact pressure, while only large size, not position, significantly reduced the predicted AR. Despite general trends, simulations revealed that optimal device size/position is patient-specific.

Rate and Predictors of Permanent Pacemaker Implantation After Transcatheter Aortic Valve Implantation: Current Status

Transcather aortic valve implantation (TAVI) has become a safe and indispensable treatment option for patients with severe symptomatic aortic stenosis who are at high surgical risk. Recently, outcomes after TAVI have improved significantly and TAVI has emerged as a qualified alternative to surgical aortic valve replacement in the treatment of intermediate risk patients and greater adoption of this procedure is to be expected in a wider patients population, including younger patients and low surgical risk patients. However since the aortic valve has close spatial proximity to the conduction system, conduction anomalies are frequently observed in TAVI. In this article, we aim to review the key aspects of pathophysiology, current incidence, predictors and clinical association of conduction anomalies following TAVI.

Outcomes of Acute Conduction Abnormalities Following Transcatheter Aortic Valve Implantation With a Balloon Expandable Valve and Predictors of Delayed Conduction System Abnormalities in Follow-up

Transcatheter aortic valve implantation (TAVI) is an acceptable treatment for severe aortic stenosis in high or intermediate risk patients. Conduction abnormalities are a known complication of TAVI. Most abnormalities occur perioperatively but can develop later. The predictors of delayed conduction abnormalities are unknown. Patients who underwent TAVI at our institution were reviewed. Patients with a pre-existing pacemaker were excluded. Baseline, in-hospital, and 30-day follow-up ECGs were reviewed. Patient and procedural characteristics were analyzed to look for predictors of acute and delayed abnormalities. Ninety-eight patients were included. All valves implanted were balloon expandable, most commonly SAPIEN S3 (78%). Thirty-seven (37.7%) patients developed abnormalities before discharge. Of these patients, 20 (57.1%) had complete resolution at 30-day follow-up. No patients with new conduction abnormalities during hospitalization had additional abnormalities at 30-day follow-up. Five (5.1%) patients developed new conduction abnormalities following discharge. Overall, 22 (22.4%) patients had conduction abnormalities at 30-day follow-up which were not present at baseline. Predilatation (p = 0.003), higher ratios of balloon (p = 0.03) or valve (p = 0.05) size to left ventricular outflow tract, and previous myocardial infarction (p = 0.034) were predictive of acute conduction abnormalities. Baseline right bundle branch block (p = 0.002), longer baseline (p <0.001) and discharge (p = 0.004) QRS duration, moderate, or severe aortic insufficiency (p = 0.002) and atrial fibrillation (p = 0.031) were predictors of new conduction abnormalities after discharge. In conclusion, most new in-hospital conduction abnormalities resolve by 30-day follow-up. In-hospital conduction abnormalities are related to technical aspects of TAVI while delayed conduction abnormalities are related to baseline conduction system disease.

Conduction Abnormalities After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) has been established as a therapeutic option for patients with severe symptomatic aortic stenosis who are of intermediate or higher surgical risk. Several periprocedural complications are reduced with newer transcatheter heart valve generations; however, conduction abnormalities and the need for permanent pacemaker implantation have remained unchanged and are the most frequent TAVR complications. The close relationship of the atrioventricular node and left bundle branch to the subaortic region explains these potential conduction abnormalities. This article highlights conduction abnormalities after TAVR with a focus on basic conduction system anatomy in relation to the aortic valve, the mechanism, incidence, predisposing factors for occurrence, impact on mortality and finally, proposed treatment algorithms for management.

Predictors and prognostic impact of new left bundle branch block after surgical aortic valve replacement

BACKGROUND

Left bundle branch block (LBBB) induces mechanical dyssynchrony that may lead to left ventricular systolic dysfunction.

AIMS

To evaluate the incidence, predictors and clinical impact of new LBBB in patients undergoing surgical aortic valve replacement (SAVR).

METHODS

After exclusion of patients with pre-existing LBBB, a previous pacemaker or a paced rhythm at hospital discharge, 547 consecutive patients undergoing SAVR were included. All-cause death, cardiovascular death and the combined outcome of all-cause death or a first heart failure event were assessed at 3months and 1year. Patients with and without new LBBB were compared.

RESULTS

New LBBB occurred in 4.6% of patients after SAVR (compared with 16.4% of patients treated by transcatheter aortic valve implantation during the study period). Previous valve surgery and an immediate postoperative paced rhythm were independent predictors of new LBBB. At 1-year follow-up, there were no significant differences in all-cause death, cardiovascular death, or the combined outcome of all-cause death or a first heart failure event between patients with and without new LBBB. However, new LBBB was associated with a trend towards functional deterioration and more heart failure events at 1year.

CONCLUSION

At 1-year follow-up, new LBBB did not have a significant impact on clinical outcome, but was associated with worse functional status and more heart failure events.

Conduction Disturbances After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) has become a well-accepted option for treating patients with aortic stenosis at intermediate to high or prohibitive surgical risk. TAVR-related conduction disturbances, mainly new-onset left bundle-branch block and advanced atrioventricular block requiring permanent pacemaker implantation, remain the most common complication of this procedure. Furthermore, improvements in TAVR technology, akin to the increasing experience of operators/centers, have translated to a major reduction in periprocedural complications, yet the incidence of conduction disturbances has remained relatively high, with perhaps an increasing trend over time. Several factors have been associated with a heightened risk of conduction disturbances and permanent pacemaker implantation after TAVR, with prior right bundle-branch block and transcatheter valve type and implantation depth being the most commonly reported. New-onset left bundle-branch block and the need for permanent pacemaker implantation may have a significant detrimental association with patients’ prognosis. Consequently, strategies intended to reduce the risk and to improve the management of such complications are of paramount importance, particularly in an era when TAVR expansion toward treating lower-risk patients is considered inevitable. In this article, we review the available evidence on the incidence, predictive factors, and clinical association of conduction disturbances after TAVR and propose a strategy for the management of these complications.

Timing of Onset and Outcome of New Conduction Abnormalities Following Transcatheter Aortic Valve Implantation: Role of Balloon Aortic Valvuloplasty

INTRODUCTION AND OBJECTIVES

Little is known about the timing of onset and outcome of conduction abnormalities (CA) following balloon-expandable transcatheter aortic valve implantation. The aim of this study was to examine the timing of CA and determine the impact of balloon aortic valvuloplasty (BAV) on the persistence of these abnormalities.

METHODS

A total of 347 patients were included. Of these, 75 had a continuous electrocardiogram recording and a 6-lead electrocardiogram at each step of the procedure.

RESULTS

In the transcatheter aortic valve implantation population undergoing continuous electrocardiogram monitoring, new-onset left bundle branch block (LBBB) or third-degree atrioventricular block occurred in 48 (64%) and 16 (21.3%) patients, with 51.5% of CA occurring before valve implantation. Left bundle branch block persisted more frequently at hospital discharge (53.8 vs 22.7%; P=.028) and at 1-month follow-up (38.5 vs 13.6%; P=.054) when occurring before valve implantation. Balloon aortic valvuloplasty prior to valve implantation was used in 264 (76.1%) patients, and 78 (22.5%) had persistent LBBB or complete atrioventricular block requiring pacemaker implantation. Persistent LBBB or unresolved atrioventricular block at 1 month occurred more frequently in the BAV group (76.1 vs 47.6%; P=.021), and the use of BAV was associated with a lack of CA resolution (OR, 3.5; 95%CI, 1.17-10.43; P=.021).

CONCLUSIONS

In patients undergoing a balloon-expandable transcatheter aortic valve implantation, more than half of CA occurred before valve implantation. Early occurrence of CA was associated with a higher rate of persistence at 1-month follow-up. The use of BAV was associated with an increased risk of CA persistence.

Transcatheter Heart Valve Selection and Permanent Pacemaker Implantation in Patients With Pre-Existent Right Bundle Branch Block

Background

Right bundle branch block is an established predictor for new conduction disturbances and need for a permanent pacemaker (PPM) after transcatheter aortic valve replacement. The aim of the study was to evaluate the absolute rates of transcatheter aortic valve replacement related PPM implantations in patients with pre‐existent right bundle branch block and categorize for different transcatheter heart valves.

Methods and Results

We pooled data on 306 transcatheter aortic valve replacement patients from 4 high‐volume centers in Europe and selected those with right bundle branch block at baseline without a previously implanted PPM. Logistic regression was used to evaluate whether PPM rate differed among transcatheter heart valves after adjustment for confounders. Mean age was 83±7 years and 63% were male. Median Society of Thoracic Surgeons score was 6.3 (interquartile range, 4.1–10.2). The following transcatheter valve designs were used: Medtronic CoreValve (n=130; Medtronic, Minneapolis, MN); Edwards Sapien XT (ES‐XT; n=124) and Edwards Sapien 3 (ES‐3; n=32; Edwards Lifesciences, Irvine, CA); and Boston Scientific Lotus (n=20; Boston Scientific Corporation, Marlborough, MA). Overall permanent pacemaker implantation rate post‐transcatheter aortic valve replacement was 41%, and per valve design: 75% with Lotus, 46% with CoreValve, 32% with ES‐XT, and 34% with ES‐3. The indication for PPM implantation was total atrioventricular block in 98% of the cases. Lotus was associated with a higher PPM rate than all other valves. PPM rate did not differ between ES‐XT and ES‐3. Ventricular paced rhythm at 30‐day and 1‐year follow‐up was present in 81% at 89%, respectively.

Conclusions

Right bundle branch block at baseline is associated with a high incidence of PPM implantation for all transcatheter heart valves. PPM rate was highest for Lotus and lowest for ES‐XT and ES‐3. Pacemaker dependency remained high during follow‐up.

Reservations about the Selvester QRS score in left bundle branch block - Experience in patients with transcatheter aortic valve implantation

BACKGROUND

The Selvester QRS score (S-score) estimates myocardial scar using electrocardiographic criteria. We evaluated the S-score for left bundle branch block (LBBB).

MATERIAL AND METHODS

Studied were 36 patients who developed persistent LBBB upon transcatheter aortic valve implantation (TAVI, TAVI-LBBB group) and 36 matched patients with persistent narrow QRS (TAVI-nQRS group). Electrocardiograms were recorded before and briefly after TAVI and during ~6months follow-up. S-score was calculated using criteria for hypertrophic (in absence of LBBB) or LBBB hearts.

RESULTS

In TAVI-LBBB patients correlation between S-scores pre-TAVI and post-TAVI was absent (R²=0.023). High S-scores post-TAVI occurred in patients with low pre-TAVI scores. Pre-post TAVI scores correlated weakly in TAVI-nQRS (R²=0.182), indicating a possible influence of ventricular unloading by TAVI. In both groups S-scores at post-TAVI and follow-up compared reasonably (R²=0.389 and R²=0.386), indicating reproducibility in more stable conditions.

CONCLUSION

This study indicates that the use of the LBBB S-score criteria overestimates scar size and that caution is recommended in the use of the score in patients with LBBB.

New-Onset Left Bundle Branch Block Induced by Transcutaneous Aortic Valve Implantation

New-onset left bundle branch block (LBBB) is a specific concern of transcutaneous aortic valve implantation (TAVI) given its estimated incidence ranging from 5% to 65%. This high rate of occurrence is dependent on the type of device used (size and shape), implantation methods, and patient co-morbidities. The appearance of an LBBB after TAVI reflects a very proximal lesion of the left bundle branch as it exits the bundle of His. At times transient, its persistence can lead to permanent pacemaker implantation in 15% to 20% of cases, most often for high-degree atrioventricular block. The management of LBBB after TAVI is currently not defined by international societies resulting in individual centers developing their own management strategy. The potential consequences of LBBB are dysrhythmias (atrioventricular block, syncope, and sudden death) and functional (heart failure) complications. Prompt postprocedural recognition and management (permanent pacemaker implantation) of patients prevents the occurrence of potential complications and may constitute the preferred approach in this frail and elderly population despite additional costs and complications of cardiac pacing. Moreover, the expansion of future indications for TAVI necessitates better identification of the predictive factors for the development of LBBB. Indeed, long-term right ventricular pacing may potentially increase the risk of developing heart failure in this population. In conclusion, it is thus imperative to not only develop new aortic prostheses with a less-deleterious impact on the conduction system but also to prescribe appropriate pacing modes in this frail population.

Conduction Abnormalities and Pacemaker Implantations After SAPIEN 3 Vs SAPIEN XT Prosthesis Aortic Valve Implantation

INTRODUCTION AND OBJECTIVES

Transcatheter aortic valve implantation is increasingly used in patients with aortic stenosis. Post-procedural intraventricular conduction abnormalities and permanent pacemaker implantations remain a serious concern. Recently, the Edwards SAPIEN 3 prosthesis has replaced the SAPIEN XT. We sought to determine the incidences of new-onset intraventricular conduction abnormalities and permanent pacemaker implantations by comparing the 2 devices.

METHODS

We analyzed the last consecutive 103 patients undergoing transcatheter aortic valve implantation with SAPIEN XT before SAPIEN 3 was used in the next 105 patients. To analyze permanent pacemaker implantations and new-onset intraventricular conduction abnormalities, patients with these conditions at baseline were excluded. Electrocardiograms were recorded at baseline, after the procedure, and before discharge.

RESULTS

SAPIEN 3 was associated with higher device success (100% vs 92%; P=.005) and less paravalvular leakage (0% vs 7%; P<.001). The incidence of permanent pacemaker implantations was 12.6% (23 of 183) with no difference between the 2 groups (SAPIEN 3: 12.5% [12 of 96] vs SAPIEN XT: 12.6% [11 of 87]; P=.99). SAPIEN 3 was associated with a higher rate of new-onset intraventricular conduction abnormalities (49% vs 27%; P=.007) due to a higher rate of fascicular blocks (17% vs 5%; P=.021). There was no statistically significant difference in transient (29% [20 of 69] vs persistent 19% [12 of 64]; P=.168) left bundle branch blocks (28% [19 of 69] vs 17% [11 of 64]; P=.154) when SAPIEN 3 was compared with SAPIEN XT.

CONCLUSIONS

We found a trend toward a higher rate of new-onset intraventricular conduction abnormalities with SAPIEN 3 compared with SAPIEN XT, although this did not result in a higher permanent pacemaker implantation rate.