The Prognostic Impact of New-Onset Persistent Left Bundle Branch Block Following Transcatheter Aortic Valve Implantation: A Meta-analysis

Impact of New-Onset Right Bundle-Branch Block After Transcatheter Aortic Valve Replacement on Permanent Pacemaker Implantation

BACKGROUND

A delayed and recurrent complete atrioventricular block (CAVB) is a life-threatening complication of transcatheter aortic valve replacement (TAVR). Post-TAVR evaluation may be important in predicting delayed and recurrent CAVB requiring permanent pacemaker implantation (PPI). The impact of new-onset right bundle-branch block (RBBB) after TAVR on PPI remains unknown.

METHODS AND RESULTS

In total, 407 patients with aortic stenosis who underwent TAVR were included in this analysis. Intraprocedural CAVB was defined as CAVB that occurred during TAVR. A 12-lead ECG was evaluated at baseline, immediately after TAVR, on postoperative days 1 and 5, and according to the need to identify new-onset bundle-branch block (BBB) and CAVB after TAVR. Forty patients (9.8%) required PPI, 17 patients (4.2%) had persistent intraprocedural CAVB, and 23 (5.7%) had delayed or recurrent CAVB after TAVR. The rates of no new-onset BBB, new-onset left BBB, and new-onset RBBB were 65.1%, 26.8%, and 4.7%, respectively. Compared with patients without new-onset BBB and those with new-onset left BBB, the rate of PPI was higher in patients with new-onset RBBB (3.4% versus 5.6% versus 44.4%, P<0.0001). On post-TAVR evaluation in patients without persistent intraprocedural CAVB, the multivariate logistic regression analysis showed that new-onset RBBB was a statistically significant predictor of PPI compared with no new-onset BBB (odds ratio [OR], 18.0 [95% CI, 5.94-54.4]) in addition to the use of a self-expanding valve (OR, 2.97 [95% CI, 1.09-8.10]).

CONCLUSIONS

Patients with new-onset RBBB after TAVR are at high risk for PPI.

Impact of new-onset arrhythmia on cardiac reverse remodeling following transcatheter aortic valve replacement: computed tomography-derived left ventricular and atrial strains

OBJECTIVE

Patients who undergo transcatheter aortic valve replacement (TAVR) are at risk for new-onset arrhythmia (NOA) that may require permanent pacemaker (PPM) implantation, resulting in decreased cardiac function. We aimed to investigate the factors that are associated with NOA after TAVR and to compare pre- and post-TAVR cardiac functions between patients with and without NOA using CT-derived strain analyses.

METHODS

We included consecutive patients who underwent pre- and post-TAVR cardiac CT scans six months after TAVR. New-onset left bundle branch block, atrioventricular block, and atrial fibrillation/flutter lasting over 30 days after the procedure and/or the need for PPM diagnosed within 1 year after TAVR were regarded as NOA. Implant depth and left heart function and strains were analyzed using multi-phase CT images and compared between patients with and without NOA.

RESULTS

Of 211 patients (41.7% men; median 81 years), 52 (24.6%) presented with NOA after TAVR, and 24 (11.4%) implanted PPM. Implant depth was significantly deeper in the NOA group than in the non-NOA group (- 6.7 ± 2.4 vs. - 5.6 ± 2.6 mm; p = 0.009). Left ventricular global longitudinal strain (LV GLS) and left atrial (LA) reservoir strain were significantly improved only in the non-NOA group (LV GLS,  - 15.5 ± 4.0 to  - 17.3 ± 2.9%; p < 0.001; LA reservoir strain, 22.3 ± 8.9 to 26.5 ± 7.6%; p < 0.001). The mean percent change of the LV GLS and LA reservoir strains was evident in the non-NOA group (p = 0.019 and p = 0.035, respectively).

CONCLUSIONS

A quarter of patients presented with NOA after TAVR. Deep implant depth on post-TAVR CT scans was associated with NOA. Patients with NOA after TAVR had impaired LV reserve remodeling assessed by CT-derived strains.

CLINICAL RELEVANCE STATEMENT

New-onset arrhythmia (NOA) following transcatheter aortic valve replacement (TAVR) impairs cardiac reverse remodeling. CT-derived strain analysis reveals that patients with NOA do not show improvement in left heart function and strains, highlighting the importance of managing NOA for optimal outcomes.

KEY POINTS

• New-onset arrhythmia following transcatheter aortic valve replacement (TAVR) is a concern that interferes with cardiac reverse remodeling. • Comparison of pre-and post-TAVR CT-derived left heart strain provides insight into the impaired cardiac reverse remodeling in patients with new-onset arrhythmia following TAVR. • The expected reverse remodeling was not observed in patients with new-onset arrhythmia following TAVR, given that CT-derived left heart function and strains did not improve.

Conductive disturbances in the transcatheter aortic valve implantation setting: An appraisal of current knowledge and unmet needs

New-onset conduction disturbances, including left bundle branch block and permanent pacemaker implantation, remain a major issue after transcatheter aortic valve implantation. Preprocedural risk assessment in current practice is most often limited to evaluation of the baseline electrocardiogram, whereas it may benefit from a multimodal approach, including ambulatory electrocardiogram monitoring and multidetector computed tomography. Physicians may encounter equivocal situations during the hospital phase, and the management of follow-up is not fully defined, despite the publication of several expert consensuses and the inclusion of recommendations regarding the role of electrophysiology studies and postprocedural monitoring in recent guidelines. This review provides an overview of current knowledge and future perspectives regarding the management of new-onset conduction disturbances in the setting of transcatheter aortic valve implantation, from the preprocedural phase to long-term follow-up.

LDL-C: An Important Independent Risk Factor for New-Onset Heart Block in Patients with Severe Aortic Stenosis and Heart Failure after TAVR

Background

Transcatheter aortic valve replacement (TAVR) is an effective alternative treatment for patients with aortic stenosis (AS) who have intermediate to high surgical risk or who are inoperable. However, the incidence of conduction abnormalities is high after TAVR, which can reduce the effectiveness of the surgery. Our research objective is to explore the risk factors of new-onset conduction abnormalities after TAVR, providing reference value for clinical doctors to better prevent and treat conduction abnormalities.

Methods

Patients who underwent TAVR were divided into those who developed heart block and those who did not. Baseline clinical characteristics, cardiac structural parameters, procedural characteristics, electrocardiogram (ECG) changes before and after TAVR ( △ = postoperative minus preoperative), and surgical complications were compared. Logistic regression was applied to identify significant risk factors for new-onset heart block.

Results

We studied 93 patients, of whom 34.4% developed heart blocks. Univariate logistic regression showed that prior history of malignancy, atrial fibrillation, preoperative high-level total cholesterol and low-density lipoprotein cholesterol (LDL-C), △ HR, △ QRS interval, △ QT interval, and △ QTc interval were risk factors of new-onset heart block after TAVR. Multivariate analysis showed that preoperative high-level LDL-C and △ QRS interval remained significant independent risk factors after adjusting for potential confounds.

Conclusions

Heart block is the most common complication of TAVR, and its significant independent risk factors include high-level LDL-C and △ QRS interval.

Transcatheter Aortic Valve Replacement in Elderly Patients: Opportunities and Challenges

Over the past two decades, the rapid evolution of transcatheter aortic valve replacement (TAVR) has revolutionized the management of severe aortic stenosis (AS) in the elderly. The prevalence of comorbidities in elderly AS patients presents a considerable challenge to the effectiveness and prognosis of patients after TAVR. In this article, we aim to summarize some of the clinical aspects of the current use of TAVR in elderly patients and attempt to highlight the challenges and issues that need further consideration.

Outcomes in patients with electrocardiographic left ventricular dyssynchrony following transcatheter aortic valve replacement

BACKGROUND

Left bundle branch block (LBBB) and atrioventricular (AV) conduction abnormalities requiring permanent pacemaker (PPM) implantation occur frequently following transcatheter aortic valve replacement (TAVR). The resultant left ventricular (LV) dyssynchrony may be associated with adverse clinical events.

OBJECTIVES

The purpose of this study was to assess the adverse outcomes associated with LV dyssynchrony due to high-burden right ventricular (RV) pacing or permanent LBBB following TAVR in patients with preserved left ventricular ejection fraction (LVEF).

METHODS

Consecutive TAVR patients at the University of Michigan from January 2012 to June 2017 were included. Pre-existing cardiac implantable electronic device, previous LBBB, LVEF <50%, or follow-up period <1 year were excluded. The primary outcome was all-cause mortality. Secondary outcomes included cardiomyopathy (defined as LVEF ≤45%), a composite endpoint of cardiomyopathy or all-cause mortality, and the change in LVEF at 1-year follow-up.

RESULTS

A total of 362 patients were analyzed (mean age 77 years). LV dyssynchrony group (n = 91 [25.1%]) included 56 permanent LBBB patients, 12 permanent LBBB patients with PPM, and 23 non-LBBB patients with PPM and high-burden RV pacing. Remaining patients served as control (n = 271 [74.9%]). After adjusted analysis, LV dyssynchrony had significantly higher all-cause mortality (adjusted hazard ratio [HR] 2.16; 95% confidence interval [CI] 1.07-4.37) and cardiomyopathy (adjusted HR 14.80; 95% CI 6.31-14.69). The LV dyssynchrony group had mean LVEF decline of 10.5% ± 10.2% compared to a small increase (0.5% ± 7.7%) in control.

CONCLUSION

Among TAVR patients with preserved LVEF and normal AV conduction, development of postprocedural LV dyssynchrony secondary to high-burden RV pacing or permanent LBBB was associated with significantly higher risk of death and cardiomyopathy at 1-year follow-up.

Incidence, predictors, and prognostic impact of temporary left bundle branch block after transcatheter aortic valve replacement

BACKGROUND

Little is known about temporary Left Bundle Branch Block (LBBB) after transcatheter aortic valve replacement (TAVR). We aim to evaluate the incidence, prognostic impact and predictors of temporary LBBB in TAVR patients.

METHODS

Electrocardiograms (ECGs) obtained before and after TAVR, at discharge and at 30-day follow-up were anonymously analyzed by 5 cardiologists. Temporary LBBB included transient LBBB or persistent LBBB. The primary endpoint was all-cause mortality at 1-year after TAVR.

RESULTS

Out of 198 patients, 55 (27.7%) developed temporary LBBB. No differences between groups were observed in primary endpoint. Left ventricular ejection fraction (LVEF) was identified as predictive factor of transient LBBB.

CONCLUSIONS

Temporary LBBB has no significant impact on survival at 1 year after the procedure.

Development of atrioventricular and intraventricular conduction disturbances in patients undergoing transcatheter aortic valve replacement with new generation self-expanding valves: A real world multicenter analysis

BACKGROUND

High degree cardiac conduction disturbances (HDCD) remain a major complication after transcatheter aortic valve replacement (TAVR), especially with self-expandable valves (SEV). Our aim was to investigate peri-procedural and in-hospital modification of atrioventricular and intracardiac conduction associated to new generation SEV implantation, and the development of new HDCD resulting in permanent pacemaker implantation (PPM) in patients undergoing TAVR.

METHODS AND RESULTS

Three-hundred forty-four consecutive patients with severe aortic stenosis who underwent TAVR with a new generation SEV [Evolut-R/Pro (n = 130), Acurate-neo (n = 79), Portico (n = 75) and Allegra (n = 60)] were included. An analysis of baseline, post-TAVR and pre-discharge ECG and procedural aspects were centrally performed. A significant increase in baseline PR interval (169.6 ± 28.2 ms) and QRS complex width (101.7 ± 25.9 ms) was noted immediately post-TAVR (188.04 ± 34.49; 129.55 ± 30.02 ms), with a partial in-hospital reversal (179.4 ± 30.1; 123.06 ± 30.94 ms), resulting in a net increase at hospital discharge of 12.6 ± 38.8 ms and 21.4 ± 31.6 ms (p < 0.001), respectively. The global incidence of new onset persistent HDCD at hospital discharge was 46.3%, with 17.7% of patients requiring PPM. Independent predictors of new onset HCDC at hospital discharge were valve recapture (OR: 2.8; 95% IC: 1.1-7.2, p = 0.033) and implantation depth ≥ 6 mm (OR: 1.9 05% IC 1.1-3.3, p = 0.015), while higher implantation (<3 mm (OR: 0.3, 95% IC 0.1-0.7, p = 0.014) and use of Acurate-Neo valve (OR: 0.4; 95% IC 0.2-0.8, p = 0.009) were protective factor.

CONCLUSIONS

New generation self-expanding aortic valves were associated with a significant increase in PR and QRS interval at hospital discharge leading to a very high rate of HDCD. While valve recapture and implantation depth were independent predictors for the occurrence of HDCD, use of Accurate-Neo valve was a protective factor.

Epidemiology, evaluation, and management of conduction disturbances after transcatheter aortic valve replacement

Aortic stenosis is the most common valvulopathy requiring replacement by means of the surgical or transcatheter approach. Transcatheter aortic valve replacement (TAVR) has quickly become a viable and often preferred treatment strategy compared to surgical aortic valve replacement. However, transcatheter heart valve system deployment not infrequently injures the specialized electrical system of the heart, leading to new conduction disorders including high-grade atrioventricular block and complete heart block (CHB) necessitating permanent pacemaker implantation (PPI), which may lead to deleterious effects on cardiac function and patient outcomes. Additional conduction disturbances (e.g., new-onset persistent left bundle branch block, PR/QRS prolongation, and transient CHB) currently lack clearly defined management algorithms leading to variable strategies among institutions. This article outlines the current understanding of the pathophysiology, patient and procedural risk factors, means for further risk stratification and monitoring of patients without a clear indication for PPI, our institutional approach, and future directions in the management and evaluation of post-TAVR conduction disturbances.

Permanent pacemaker implantation late after transcatheter aortic valve implantation

BACKGROUND

Impairment of atrioventricular (AV) conduction may occur late after transcatheter aortic valve implantation (TAVI), and progression to complete AV block is a matter of concern.

OBJECTIVE

The purpose of this study was to describe the incidence of permanent pacemaker (PPM) implantation late after TAVI.

METHODS

In a prospective TAVI registry, we retrospectively identified patients with PPM implantation after hospital discharge for TAVI and analyzed serial electrocardiograms for AV conduction impairment before PPM implantation.

RESULTS

Among 1059 patients discharged after TAVI without PPM between January 2012 and December 2017, 62 patients (5.9%) underwent PPM implantation at a median of 305 days after discharge for TAVI. Indications for PPM implantation late after TAVI were AV conduction impairment in 46 patients (74.2%); sick sinus syndrome in 10 (16.1%); cardiac resynchronization or implantable cardioverter-defibrillator indication in 2 (3.2%); and a pace and ablate strategy in 4 (6.5%). Clinical symptoms leading to PPM implantation late after TAVI included syncope in 19 patients (30.7%), presyncope in 7 (11.3%), and dyspnea in 8 (12.9%). First-degree AV block and new left bundle branch block (LBBB) after TAVI as well as valve-in-valve procedure during follow-up were independent predictors of PPM implantation late after TAVI due to AV conduction impairment.

CONCLUSION

PPM implantation late after TAVI is infrequent and is associated with clinical symptoms in half of patients. Impairment of AV conduction was the indication in three-quarters of patients. First-degree AV block and new LBBB after TAVI as well as valve-in-valve procedure during follow-up emerged as independent predictors.

Predictors of Permanent Pacemaker Implantation in Patients Undergoing Transcatheter Aortic Valve Replacement - A Systematic Review and Meta-Analysis

Background

As transcatheter aortic valve replacement (TAVR) technology expands to healthy and lower‐risk populations, the burden and predictors of procedure‐related complications including the need for permanent pacemaker (PPM) implantation needs to be identified.

Methods and Results

Digital databases were systematically searched to identify studies reporting the incidence of PPM implantation after TAVR. A random‐ and fixed‐effects model was used to calculate unadjusted odds ratios (OR) for all predictors. A total of 78 studies, recruiting 31 261 patients were included in the final analysis. Overall, 6212 patients required a PPM, with a mean of 18.9% PPM per study and net rate ranging from 0.16% to 51%. The pooled estimates on a random‐effects model indicated significantly higher odds of post‐TAVR PPM implantation for men (OR, 1.16; 95% CI, 1.04–1.28); for patients with baseline mobitz type‐1 second‐degree atrioventricular block (OR, 3.13; 95% CI, 1.64–5.93), left anterior hemiblock (OR, 1.43; 95% CI, 1.09–1.86), bifascicular block (OR, 2.59; 95% CI, 1.52–4.42), right bundle‐branch block (OR, 2.48; 95% CI, 2.17–2.83), and for periprocedural atriorventricular block (OR, 4.17; 95% CI, 2.69–6.46). The mechanically expandable valves had 1.44 (95% CI, 1.18–1.76), while self‐expandable valves had 1.93 (95% CI, 1.42–2.63) fold higher odds of PPM requirement compared with self‐expandable and balloon‐expandable valves, respectively.

Conclusions

Male sex, baseline atrioventricular conduction delays, intraprocedural atrioventricular block, and use of mechanically expandable and self‐expanding prosthesis served as positive predictors of PPM implantation in patients undergoing TAVR.

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.

Short- and Long-Term Outcomes in Patients With New-Onset Persistent Left Bundle Branch Block After Transcatheter Aortic Valve Replacement

BACKGROUND

The impact of new-onset persistent left bundle branch block (LBBB) after transcatheter aortic valve replacement (TAVR) on all-cause mortality has been controversial.

METHODS

We conducted a systematic review and meta-analysis of eleven studies (7398 patients) comparing the short- and long- outcomes in patients who had new-onset LBBB after TAVR vs. those who did not.

RESULTS

During a mean follow-up of 20.5±14months, patients who had new-onset persistent LBBB after TAVR had a higher incidence of all-cause mortality (29.7% vs. 23.6%; OR 1.28 (1.04-1.58), p=0.02), rehospitalization for heart failure (HF) (19.5% vs. 17.3%; OR 1.4 (1.13-1.73), p=0.002), and permanent pacemaker implantation (PPMi) (19.7% vs. 7.1%; OR 2.4 (1.64-3.52), p<0.001) compared with those who did not. Five studies (4180 patients) reported adjusted hazard ratios (HR) for all-cause mortality; new LBBB remained associated with a higher risk of mortality (adjusted HR 1.43 (1.08-1.9), p<0.01, I²=81%).

CONCLUSION

Post-TAVR persistent LBBB is associated with higher PPMi, HF hospitalizations, and all-cause mortality. While efforts to identify patients who need post-procedural PPMi are warranted, more studies are required to evaluate the best follow-up and treatment strategies, including the type of pacing device if required, to improve long-term outcomes in these patients.

Electrophysiology Testing to Stratify Patients With Left Bundle Branch Block After Transcatheter Aortic Valve Implantation

Background Left bundle branch block (LBBB) is common after transcatheter aortic valve implantation (TAVI) and is an indicator of subsequent high-grade atrioventricular block (HAVB). No standardized protocol is available to identify LBBB patients at risk for HAVB. The aim of the current study was to evaluate the safety and efficacy of an electrophysiology study tailored strategy in patients with LBBB after TAVI. Methods and Results We prospectively analyzed consecutive patients with LBBB after TAVI. An electrophysiology study was performed to measure the HV-interval the day following TAVI. In patients with normal His-ventricular (HV)-interval ≤55 ms, a loop recorder was implanted (ILR-group), whereas pacemaker implantation was performed in patients with prolonged HV-interval >55 ms (PM-group). The primary end point was occurrence of HAVB during a follow-up of 12 months. Secondary end points were symptoms, hospitalizations, adverse events because of device implantation or electrophysiology study, and death. Of 373 patients screened after TAVI, 56 patients (82±6 years, 41% male) with LBBB were included. HAVB occurred in 4 of 41 patients (10%) in the ILR-group and in 8 of 15 patients (53%) in the PM-group (P<0.001). We did not identify other predictors for HAVB than the HV interval. The negative predictive value for the cut-off of HV 55 ms to detect HAVB was 90%. No HAVB-related syncope occurred in the 2 groups. Conclusions An electrophysiology study tailored strategy to LBBB after TAVI with a cut-off of HV >55 ms is a feasible and safe approach to stratify patients with regard to developing HAVB during a follow-up of 12 months.

Need for pacemaker implantation in patients with normal QRS duration immediately after transcatheter aortic valve implantation

Aims

We sought to assess the need for permanent pacemaker implantation (PPI) in patients with QRS <120 ms in electrocardiogram (ECG) after transcatheter aortic valve implantation (TAVI).

Methods and results

We retrospectively analysed 1139 consecutive patients who underwent transfemoral TAVI between 2008 and 2016, receiving different valve types. All patients were surveyed by continuous ECG monitoring for 48 h, 12-lead ECGs starting immediately after procedure, as well as 24-h Holter recording the day before discharge. Indication for PPI was at the discretion of the attending physician. Among 760 patients with QRS <120 ms prior to the TAVI procedure, 400 patients showed QRS <120 ms immediately after procedure, whereas 360 patients had QRS ≥120 ms. In the group with QRS <120 ms, PPI was performed in 34 patients [8.5%; 95% confidence interval (CI) 5.6–11.2%] during the first week. Eight of the PPIs in the group with QRS <120 ms (2%; CI 0.8–3.5%) fulfilled Class I indications for PPI after TAVI, whereas 26 PPIs had different indications [left bundle branch block, sick sinus, low-grade atrioventricular (AV) block]. Complete AV block developed in three patients of the group of QRS <120 ms (0.75%; CI 0.0–1.7%), which in all cases occurred after the 48 h-surveillance period. During 1-year follow-up, 11 PPIs were performed (2.8%; CI 1.2–4.5%), thereof three PPI for Class I indications including one complete AV block.

Conclusion

In patients with QRS duration <120 ms immediately after TAVI, the risk for complete AV block was low during the first week after TAVI and 1-year follow-up.

Mechanical Intervention for Aortic Valve Stenosis in Patients With Heart Failure and Reduced Ejection Fraction

The risk and benefit of mechanical interventions in valvular heart disease have been primarily described among patients with normal ejection fraction. The advent of nonsurgical mechanical interventions for aortic stenosis (transcatheter aortic valve replacement) may alter the risk-benefit ratio for patients who would otherwise be at increased risk for valve surgery. This review describes the epidemiology and pathophysiology of aortic stenosis with heart failure and reduced ejection fraction and summarizes the current registry and clinical trial data applicable to this frequently encountered high-risk group. It concludes with discussion of ongoing trials, new approaches, emerging indications, and a potential clinical algorithm incorporating optimal mechanical intervention for patients with aortic stenosis and concomitant reduced ejection fraction.

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.

Association between implantation depth assessed by computed tomography and new-onset conduction disturbances after transcatheter aortic valve implantation

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is often associated with intraventricular conduction disturbances. We aimed to determine the association between implantation depth assessed by multidetector computed tomography (MDCT) and new-onset conduction abnormalities after TAVR.

METHODS

Retrospective single-center study including patients consecutively submitted to TAVR, between August/2007 and October/2016, who underwent routine MDCT 3 months after the procedure. The endpoint of conduction disturbances included permanent pacemaker implantation and/or new-onset left bundle-branch block. Implantation depth was determined as the distance between the ventricular end of the prothesis and the native ring, at the level of the non-coronary cusp.

RESULTS

138 patients were included (female gender 52.2%, mean age 78.7 ± 6.9 years). The EuroSCORE II was 4.0 ± 3.9% and 57.2% were treated with self-expanding prosthesis. The endpoint of conduction abnormalities was found in 45.7% (n = 63). The implantation depth was greater in the group with conduction disturbances (7.7 vs 6.4 mm, p = 0.006). Chronic obstructive pulmonary disease, oversizing and implantation depth were independent predictors of conduction abnormalities. Implantation depth had an AUC of 0.64 (p = 0.004) for the prediction of conduction abnormalities and a cut-off value of 7.1 mm predicted the composed endpoint with a sensitivity and specificity of 65% and 70%, respectively.

CONCLUSIONS

Implantation depth assessed by MDCT is associated with new-onset conduction disturbances after TAVR. In patients with conduction abnormalities, which do not qualify for the immediate implantation of pacemaker, the assessment of implantation depth by MDCT may be an additional marker of risk to aid decision-making.

Pathophysiology, incidence and predictors of conduction disturbances during Transcatheter Aortic Valve Implantation

INTRODUCTION

Over the past decade, transcatheter aortic valve implantation (TAVI) has evolved rapidly toward an extremely reproducible, safe and effective procedure, with a marked reduction of its related complications. However, the occurrence of conduction disturbances and the need for permanent pacemaker implantation (PPI) after TAVI remains a concern. Areas covered: In this article review, we will go through the mechanisms involved in conduction disturbances after TAVI, and we will discuss the key aspects of pathophysiology, incidence and predictors of conduction disturbances following Transcatheter Aortic Valve Implantation. The evaluation of patient's valve anatomy and the selection of the most appropriate prosthesis have been proposed as a valuable options to reduce the incidence of conductions disturbances. Moreover, in recent times, a great number of new TAVI devices, so-called 'second-generation devices', have been introduced to address the limitations of the first-generation devices, including conduction disturbance, with scarce results. Expert commentary: Conduction disturbances after TAVI are increasingly recognized as an important issue in TAVI complications. Further characterization of the procedural- and patient-related factors that contribute to the development of conduction abnormalities will help to improve prosthesis designs and patient selection, making TAVI even more safer.