Real-Time Analysis of Conduction Disturbances During TAVR With the CARA Monitor

BACKGROUND

The occurrence of conduction disturbances (CDs) remains the most frequent complication of transcatheter aortic valve replacement (TAVR). However, little is known about the timing of electrocardiogram (ECG) changes and CDs during the TAVR procedure.

OBJECTIVE

To describe ECG changes throughout the TAVR procedure using the CARA monitor.

METHODS

Multicenter study including 196 prospectively enrolled patients with no CDs undergoing TAVR. All patients were monitored with the CARA system, which uses a 12-lead ECG to measure PQ and QRS intervals, QRS axis, and variations with each heartbeat at every step: baseline, wire insertion, pre-dilatation, valve deployment, post-dilatation, and end of procedure.

RESULTS

PQ and QRS intervals progressively increased throughout the procedure, with a cumulative increase from 169.0±20.0ms to 186.0±31.6ms (P<0.001) for the PQ interval and from 101.3±10.5ms to 126.0±25.4ms (P<0.001) for the QRS interval, from baseline to the end of the procedure. A significant increase in the number of patients with left axis deviation was observed (8% at baseline vs 32% at end of procedure, P<0.001). A total of 161 (82.4%) patients exhibited at least one CD episode (PQ>200ms, QRS>120ms, advanced heart block) during the procedure, with most episodes occurring during pre-dilatation and valve implantation maneuvers.

CONCLUSIONS

The CARA system facilitated real-time ECG monitoring, detecting subtle and progressive changes during TAVR. ECG changes occurred at each step, with most patients experiencing CDs, especially during pre-dilatation and valve implantation. The potential of ECG dynamics and timing for early detection of severe CDs should be explored in future studies.

Decreasing pacemaker implantation rates with Evolut supra-annular transcatheter aortic valves in a large real-world registry

BACKGROUND

Permanent pacemaker implantation (PPI) rates following transcatheter aortic valve replacement (TAVR) remain a concern. We assessed the PPI rates over time in patients implanted with an Evolut supra-annular, self-expanding transcatheter valve from the US STS/ACC TVT Registry.

METHODS

Patients who underwent TAVR with an Evolut R, Evolut PRO or Evolut PRO+ valve between July 2018 (Q3) and June 2021 (Q2) were included. PPI rates were reported by calendar quarter. In-hospital PPI rates were reported as proportions and 30-day rates as Kaplan-Meier estimates. A Cox regression model was used to determine potential predictors of a new PPI within 30 days of the TAVR procedure.

RESULTS

From July 2018 to June 2021, 54,014 TAVR procedures were performed using Evolut valves. Mean age was 79.3 ± 8.8 years and 49.2 % were male. The 30-day PPI rate was 16.6 % in 2018 (Q3) and 10.8 % in 2021 (Q2, 34.9 % decrease, p < 0.001 for trend across all quarters). The in-hospital PPI rate decreased by 40.1 %; from 14.7 % in 2018 (Q3) to 8.8 % in 2021 (Q2) (p < 0.001 for trend across all quarters). Significant predictors of a new PPI within 30 days included a baseline conduction defect, history of atrial fibrillation, home oxygen, and diabetes mellitus.

CONCLUSION

From 2018 to 2021, TAVR with an Evolut transcatheter heart valve in over 50,000 patients showed a significant decreasing trend in the rates of in-hospital and 30-day PPI, representing the lowest rate of PPI in any large real-world registry of Evolut. During the same evaluated period, high device success and shorter length of stay was also observed.

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.

Predictors of New and Persistent New Left Bundle Branch Block One Year after the Implantation of a Sutureless and Rapid-Deployment Aortic Valve Prosthesis

INTRODUCTION

Conduction disorders following aortic valve replacement therapy (AVR), either surgical or percutaneous, are related to a higher risk of complete atrioventricular block and permanent pacemaker implantation (PPI).

AIM

The objective of this study was to assess risk factors regarding the incidence of new postoperative and persistent new left bundle branch block (LBBB) 1 year after the implantation of a sutureless/rapid-deployment (SURD) aortic valve prosthesis.

MATERIAL AND METHODS

The current study included 200 consecutive patients treated with isolated or concomitant AVR between May 2014 and May 2017 at the Department of Cardiac Surgery in Pasawa with SURD aortic valve EDWARDS INTUITY EliteTM implantation. The patients were divided according to the presence of new postoperative LBBB (67 patients, 33.5%) and persistent new LBBB 1 year after AVR (35 patients, 17.5%). A comparative analysis was performed between patients with and without new LBBB after AVR and those with and without persistent LBBB 1 year after AVR. Univariate and multivariate regression analyses were conducted to extract the risk factors of LBBB occurrence.

RESULTS

Among the risk factors for the lack of new LBBB development after AVR, Euroscore II (p < 0.001) was found, while for the occurrence of persistent new LBBB 1 year after AVR, atrial fibrillation (p = 0.001), length of hospital stay (p = 0.001) and body mass index (p = 0.004) were noted.

CONCLUSIONS

Patients with new or persistent new LBBB 1 year after AVR had lower mean Euroscore II and BMI values. Their stay at the hospital was also shorter.

Rationale and Design of the Randomized Bayesian Multicenter COME-TAVI Trial in Patients With a New Onset Left Bundle Branch Block

Patients with new-onset left bundle branch block (LBBB) after transcatheter aortic valve implantation (TAVI) are at risk of developing delayed high-degree atrioventricular block. Management of new-onset LBBB post-TAVI remains controversial. In the Comparison of a Clinical Monitoring Strategy Versus Electrophysiology-Guided Algorithmic Approach in Patients With a New LBBB After TAVI (COME-TAVI) trial, consenting patients with new-onset LBBB that persists on day 2 after TAVI, meeting exclusion/inclusion criteria, are randomized to an electrophysiological study (EPS)-guided approach or 30-day electrocardiographic monitoring. In the EPS-guided approach, patients with a His to ventricle (HV) interval ≥ 65 ms undergo permanent pacemaker implantation. Patients randomized to noninvasive monitoring receive a wearable continuous electrocardiographic recording and transmitting device for 30 days. Follow-up will be performed at 3, 6, and 12 months. The primary endpoint is a composite outcome designed to capture net clinical benefit. The endpoint incorporates major consequences of both strategies in patients with new-onset LBBB after TAVI, as follows: (i) sudden cardiac death; (ii) syncope; (iii) atrioventricular conduction disorder requiring a pacemaker (for a class I or IIa indication); and (iv) complications related to the pacemaker or EPS. The trial incorporates a Bayesian design with a noninformative prior, outcome-adaptive randomization (initially 1:1), and 2 prespecified interim analyses once 25% and 50% of the anticipated number of primary endpoints are reached. The trial is event-driven, with an anticipated upper limit of 452 patients required to reach 77 primary outcome events over 12 months of follow-up. In summary, the aim of this Bayesian multicentre randomized trial is to compare 2 management strategies in patients with new-onset LBBB post-TAVI-an EPS-guided approach vs noninvasive 30-day monitoring. Trial registration number: NCT03303612.

Risk Factors, Management, and Avoidance of Conduction System Disease after Transcatheter Aortic Valve Replacement

Transcatheter valve replacement (TAVR) is a rapidly developing modality to treat patients with aortic stenosis (AS). Conduction disease post TAVR is one of the most frequent and serious complications experienced by patients. Multiple factors contribute to the risk of conduction disease, including AS and the severity of valve calcification, patients' pre-existing conditions (i.e., conduction disease, anatomical variations, and short septum) in addition to procedure-related factors (e.g., self-expanding valves, implantation depth, valve-to-annulus ratio, and procedure technique). Detailed evaluation of risk profiles could allow us to better prevent, recognize, and treat this entity. Available evidence on management of conduction disease post TAVR is based on expert opinion and varies widely. Currently, conduction disease in TAVR patients is managed depending on patient risk, with minimal-to-no inpatient/outpatient observation, inpatient monitoring (24-48 h) followed by ambulatory monitoring, or either prolonged inpatient and outpatient monitoring or permanent pacemaker implantation. Herein, we review the incidence and risk factors of TAVR-associated conduction disease and discuss its management.

[Left bundle branch block - dilated cardiomyopathy - heart failure: common links in the closed pathogenetic chain]

This review summarizes the available information on the epidemiology and prognosis of patients with left bundle branch block (LBBB), morphological alterations of the myocardium both resulting in and ensuing LBBB, cardiac biomechanics in LBBB, and possibilities of its correction.

New-onset persistent left bundle branch block following sutureless aortic valve replacement

OBJECTIVE

To evaluate the incidence, predictive factors and prognostic value of new-onset persistent left bundle branch block (NOP-LBBB) in patients undergoing sutureless surgical aortic valve replacement (SU-SAVR).

METHODS

A total of 329 consecutive patients without baseline conduction disturbances or previous permanent pacemaker implantation (PPI) who underwent SU-SAVR with the Perceval valve (LivaNova Group, Saluggia, Italy) in two centres from 2013 to 2019 were included. Patients were on continuous ECG monitoring during hospitalisation and 12-lead ECG was performed after the procedure and at hospital discharge. NOP-LBBB was defined as a new postprocedural LBBB that persisted at hospital discharge. Baseline, procedural and follow-up clinical and echocardiography data were collected in a dedicated database.

RESULTS

New-onset LBBB was observed in 115 (34.9%) patients, and in 76 (23.1%) persisted at hospital discharge. There were no differences in baseline and procedural characteristics between patients with (n=76) and without (n=253) NOP-LBBB. After a median follow-up of 3.3 years (2.3-4.4 years), patients with NOP-LBBB had a higher incidence of PPI (14.5% vs 6.3%, p=0.016), but exhibited similar rates of all-cause mortality (19.4% vs 19.2%, p=0.428), cardiac mortality (8.1% vs 9.4%, p=0.805) and heart failure readmission (21.0% vs 23.2%, p=0.648), compared with the no/transient LBBB group. NOP-LBBB was associated with a decrease in left ventricular ejection fraction (LVEF) at 1-year follow-up (delta: -5.7 vs +0.2, p<0.001).

CONCLUSIONS

NOP-LBBB occurred in approximately a quarter of patients without prior conduction disturbances who underwent SU-SAVR and was associated with a threefold increased risk of PPI along with a negative impact on LVEF at follow-up.

Short-Term Atrioventricular Dysfunction Recovery after Post-TAVI Pacemaker Implantation

Permanent pacemaker implantation (PPI) represents a frequent complication after transcatheter aortic valve implantation (TAVI) due to atrio-ventricular (AV) node injury. Predictors of early AV function recovery were investigated. We analyzed 50 consecutive patients (82 ± 6 years, 58% males, EuroSCORE: 7.8 ± 3.3%, STS mortality score: 5 ± 2.8%). Pacemaker interrogations within 4−6 weeks from PPI were performed to collect data on AV conduction. The most common indication of PPI was persistent third-degree (44%)/high-degree (20%) AV block/atrial fibrillation (AF) with slow ventricular conduction (16%) after TAVI. At follow-up, 13 patients (26%) recovered AV conduction (i.e., sinus rhythm with stable 1:1 AV conduction/AF with a mean ventricular response >50 bpm, associated with a long-term ventricular pacing percentage < 5%). At multivariate analysis, complete atrio-ventricular block independently predicted pacemaker dependency at follow-up (p = 0.019). Patients with persistent AV dysfunction showed a significant AV conduction time prolongation after TAVI (PR interval from 207 ± 50 to 230 ± 51, p = 0.02; QRS interval from 124 ± 23 to 147 ± 16, p < 0.01) compared to patients with recovery, in whom AV conduction parameters remained unchanged. Several patients receiving PPI after TAVI have recovery of AV conduction within a few weeks. Longer observation periods prior to PPI might be justified, and algorithms to minimize ventricular pacing should be utilized whenever possible.

Atrioventricular conduction in PM recipients after transcatheter aortic valve implantation: Implications using Wenckebach point measurement

Background

Atrioventricular (AV) conduction disturbances requiring permanent pacemaker implantation (PPI) are a common complication after transcatheter aortic valve implantation (TAVI). However, a significant proportion of patients might recover AV conduction at follow-up.

Objectives

The aim of our study was to evaluate the recovery of AV conduction by determination through Wenckebach point in patients with PPI and therefore identify patients who could benefit from device reprogramming to avoid unnecessary RV pacing.

Methods

We enrolled 43 patients that underwent PM implantation after TAVI at our Department from January 2018 to January 2021. PM interrogation was performed at follow-up and patients with native spontaneous rhythm were further assessed for AV conduction through WP determination.

Results

A total of 43 patients requiring a PM represented the final study population, divided in patients with severely impaired AV conduction (no spontaneous valid rhythm or WP < 100; 26) and patients with valid AV conduction (WP ≥ 100; 17). In the first group patients had a significantly higher number of intraprocedural atrioventricular block (AVB) (20 vs. 1, p < 0.005), showed a significant higher implantation depth in LVOT (7.7 ± 2.2 vs. 4.4 ± 1.1, p < 0.05) and lower ΔMSID (-0.28 ± 3 vs. -3.94 ± 2, p < 0.05).

Conclusion

AV conduction may recover in a significant proportion of patients. In our study, valve implantation depth in the LVOT and intraprocedural AV block are associated with severely impaired AV conduction. Regular PM interrogation and reprogramming are required to avoid unnecessary permanent right ventricular stimulation in patients with AV conduction recovery.

A computational framework for post-TAVR cardiac conduction abnormality (CCA) risk assessment in patient-specific anatomy

BACKGROUND

Cardiac conduction abnormality (CCA)- one of the major persistent complications associated with transcatheter aortic valve replacement (TAVR) may lead to permanent pacemaker implantation. Localized stresses exerted by the device frame on the membranous septum (MS) which lies between the aortic annulus and the bundle of His, may disturb the cardiac conduction and cause the resultant CCA. We hypothesize that the area-weighted average maximum principal logarithmic strain (AMPLS) in the MS region can predict the risk of CCA following TAVR.

METHODS

Rigorous finite element-based modeling analysis was conducted in two patients (Balloon expandable TAVR recipients) to assess post-TAVR CCA risk. Following the procedure one of the patients required permanent pacemaker (PPM) implantation while the other did not (control case). Patient-specific aortic root was modeled, MS was identified from the CT image, and the TAVR deployment was simulated. Mechanical factors in the MS region such as logarithmic strain, contact force, contact pressure, contact pressure index (CPI) and their time history during the TAVR deployment; and anatomical factors such as MS length, implantation depth, were analyzed.

RESULTS

Maximum AMPLS (0.47 and 0.37, respectively), contact force (0.92 N and 0.72 N, respectively), and CPI (3.99 and 2.86, respectively) in the MS region were significantly elevated in the PPM patient as compared to control patient.

CONCLUSION

Elevated stresses generated by TAVR devices during deployment appear to correlate with CCA risk, with AMPLS in the MS region emerging as a strong predictor that could be used for preprocedural planning in order to minimize CCA risk.

Late-onset atrioventricular block after transcatheter aortic valve replacement

Background

Conduction disturbances leading to permanent pacemaker implantation (PPI) rarely occur late after transcatheter aortic valve replacement (TAVR). The clinical features of this phenomenon and its association with periprocedural conduction disturbances remain uncertain.

Objectives

We aimed to determine the incidence and characteristics of late-onset atrioventricular block (AVB) after TAVR.

Methods

This single-center study included 246 patients undergoing TAVR. Late-onset AVB was defined as AVB ≥1 month after the TAVR.

Results

Periprocedural AVB (periAVB) occurred in 43 patients (17%). Patients with periAVB had a higher rate of right bundle branch block (47% vs 7%, P < .0001). Of the 43 patients with periAVB, 15 underwent PPI (35%) at a median duration of 6 days, whereas 1 of the remaining 203 patients without periAVB underwent PPI within 1 month (0.5%). During a median follow-up duration of 365 days, late-onset AVB occurred in 10 of 230 patients without PPI within 1 month (4%) at a median duration of 76 days. All 10 patients presented transient periprocedural atrioventricular conduction disturbances, including 8 patients with periAVB (80%), all of whom recovered within 1 month, and 9 patients underwent self-expanding valve implantation (90%). The mortality rate in patients with PPI within 1 month was higher than in those without, although the difference was not statistically significant (hazard ratio 2.68, 95% confidence interval 0.97–9.05, log-rank P = .09).

Conclusion

Late-onset AVB occurred in a minority of patients undergoing TAVR. Greater vigilance is warranted, particularly in patients with transient conduction disturbances during the periprocedural period following self-expanding valve implantation.

Pre-dilation and Post-dilation in Transcatheter Aortic Valve Replacement: Indications, Benefits and Risks

Transcatheter aortic valve replacement (TAVR) is an established treatment for patients with symptomatic severe aortic stenosis. In recent years, an emphasis has been placed on simplification of the procedure. Balloon predilation was initially considered a mandatory step to cross and prepare the stenotic aortic valve, but several studies demonstrated the feasibility of performing TAVR without balloon valvuloplasty. Balloon postdilation of the implanted valve is sometimes required to optimise results, although many patients do not require this step. Contemporary consensus advocates an individualised approach to TAVR procedures and so balloon pre- and post-dilation are performed selectively. This review aims to outline the advantages and disadvantages of balloon pre- and post-dilation and to identify the scenarios in which they are required during TAVR procedures.

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.

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.

Clinical consequences of consecutive self-expanding transcatheter heart valve iterations

Objective

To compare early clinical outcomes after transcatheter aortic valve implantation (TAVI) with three consecutive generations of self-expanding valves (SEVs).

Methods

Clinical endpoints of consecutive patients who underwent TAVI with CoreValve, Evolut R or Evolut PRO were included in a prospective database.

Results

TAVI was performed with CoreValve (n = 116), Evolut R (n = 160) or Evolut PRO (n = 92). Evolut R and Evolut PRO showed a tendency towards lower permanent pacemaker implantation (PPI) rates compared to CoreValve (CoreValve 27% vs Evolut R 16% vs Evolut PRO 18%, p = 0.091). By multivariable regression analysis CoreValve had a significantly higher risk for PPI (odds ratio (OR) 2.79, 95% confidence interval (CI) 1.31–5.94, p = 0.008) compared to Evolut R, while Evolut R and PRO were similar. Severe paravalvular leakage (PVL) occurred only with CoreValve, but no significant difference was observed in moderate PVL (10% vs 8% vs 6%, p = 0.49). CoreValve had a tendency towards a higher risk for more-than-mild PVL as compared with the Evolut platform (R + PRO) (OR 2.46, 95% CI 0.98–6.16, p = 0.055). No significant differences in all-cause mortality (7% vs 4% vs 1%, p = 0.10), stroke (6% vs 3% vs 2%, p = 0.21) or major vascular complications (10% vs 12% vs 4%, p = 0.14) were observed.

Conclusions

TAVI with self-expanding valves was safe, and device iterations may result in a lower need for PPI. More-than-mild PVL seemed to occur less often with repositionable technology.

Supplementary Information

The online version of this article (10.1007/s12471-021-01568-5) contains supplementary material, which is available to authorized users.

Impact of baseline and newly acquired conduction disorders on need for permanent pacemakers with 3 consecutive generations of self-expanding transcatheter aortic heart valves

INTRODUCTIONS

We aimed to compare conduction dynamics and need for permanent pacemaker implantation (PPI) after CoreValve, Evolut R and PRO (transcatheter aortic valve replacement (TAVR)).

METHODS

Patients were stratified based on conduction at baseline; Cohort A had normal conduction, Cohort B had conduction abnormalities including atrioventricular (AV)-block, fascicular block or complete bundle branch block. Three different dynamic QRS-patterns were defined: stable QRS-duration, transient QRS-prolongation and persistent QRS-prolongation. We performed multivariable regression analysis to estimate the effect of the three separate transcatheter heart valves (THV's) on need for PPI at 30 days.

RESULTS

TAVR was performed with CoreValve (N = 113), Evolut R (N = 157) or Evolut PRO (N = 92). Conduction dynamics were similar between the different THVs. Overall, Evolut R and PRO showed a tendency towards less PPI compared to CoreValve (17% vs. 19% vs. 27%, P = 0.08), which was driven by a lower PPI rate in Cohort A (6% vs. 11% vs. 25%, P = 0.002). Need for PPI was restricted to patients with persistent QRS-prolongation in Cohort A (26/106) but did not correlate with conduction dynamics in Cohort B. In multivariable logistic regression analysis the use of Evolut R (OR 0.38, 95% CI 0.19-0.78, P = 0.008) and PRO (OR 0.41, 95% CI 0.19-0.91, P-value = 0.028) were independently associated with less need for PPI.

CONCLUSION

The newer generations Evolut R and PRO were associated with less PPI compared to CoreValve. Acquired persistent conduction abnormalities predicted PPI after TAVR only in patients with normal conduction at baseline. Our findings may help identify eligible patients for early discharge after Evolut R/PRO TAVR.

The incidence and impact of cardiac conduction disturbances after transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) has developed into an established therapy for patients with severe aortic stenosis (AS) across the spectrum of surgical risk. Despite improvements in transcatheter heart valve (THV) technologies and procedural techniques, cardiac conduction disturbances, including high degree atrioventricular block (AVB) requiring permanent pacemaker (PPM) implantation and new-onset left bundle branch block (LBBB), remain frequent complications. TAVR-related conduction disturbances occur due to injury to the conduction system from interactions with interventional equipment and the transcatheter valve stent frame. Risk factors for post-TAVR conduction disturbances have been identified and include clinical characteristics, baseline electrocardiogram findings (right bundle branch block), anatomic factors, and potentially modifiable procedural factors (type of transcatheter valve, depth of implantation, over-sizing). New-onset LBBB and PPM implantation after TAVR have been shown to be associated with adverse long-term clinical outcomes, including mortality and heart failure hospitalization. These clinical consequences are likely to be of increasing importance as TAVR is utilized in younger and lower risk population. This review provides an updated overview of the literature regarding the incidence, predictors, and clinical outcomes of TAVR-related conduction disturbances, as well as proposed strategies for the management of this frequent clinical challenge.

3D printed patient-specific aortic root models with internal sensors for minimally invasive applications

Minimally invasive surgeries have numerous advantages, yet complications may arise from limited knowledge about the anatomical site targeted for the delivery of therapy. Transcatheter aortic valve replacement (TAVR) is a minimally invasive procedure for treating aortic stenosis. Here, we demonstrate multimaterial three-dimensional printing of patient-specific soft aortic root models with internally integrated electronic sensor arrays that can augment testing for TAVR preprocedural planning. We evaluated the efficacies of the models by comparing their geometric fidelities with postoperative data from patients, as well as their in vitro hemodynamic performances in cases with and without leaflet calcifications. Furthermore, we demonstrated that internal sensor arrays can facilitate the optimization of bioprosthetic valve selections and in vitro placements via mapping of the pressures applied on the critical regions of the aortic anatomies. These models may pave exciting avenues for mitigating the risks of postoperative complications and facilitating the development of next-generation medical devices.

A single-centre cohort and short-term follow-up of patients who developed persistent new onset left bundle branch block after transcatheter aortic valve replacement

Background: The most common conduction abnormality after transcatheter aortic valve replacement (TAVR) is new-onset left bundle branch block (LBBB) with an exact frequency that varies based on the valve system used for TAVR. PPM implantation in patients with persistent new onset LBBB post TAVR is controversial. The primary objective of this study is to report PPM utilisation and mortality in this patient population.Methods: A TAVR registry included patients older than 18 years who underwent TAVR between March 2012 and June 2015 at University of Minnesota Medical Centre. After exclusion, 151 patients were divided into two groups; patients with persistent new onset LBBB after TAVR (new LBBB, n = 47) and patients without persistent new onset LBBB (no new LBBB, n = 104).Results: Among the 151 patients, 47 (31.1%) patients developed new-onset LBBB after the procedure and persisted at discharge. Left ventricular ejection fraction (LVEF) (52.5 ± 11.1 vs. 56.4 ± 10.8, p: .047) and mean aortic valve gradient (40.6 ± 11.5 vs. 45.7 ± 14.1, p: .022) were significantly higher in no new LBBB group. Among those with new LBBB, there was a significantly higher rate of PPM implant during index hospitalisation (14.9%, vs. 0%, p < .001). LVEF remained significantly lower at 1 year follow up in new LBBB group compared to no new LBBB group (51.8 ± 11.2 vs. 57.6 ± 8.3, p: .002). Also in new LBBB group, there was a non-significantly higher rate of all-cause mortality in 1 year compared to no new LBBB group (14.9% vs. 9.6% p: .34). There were no significant differences between patients with and without new LBBB with respect to PPM implant after discharge in 1 year (2.13% vs. 3.8% p: .58), length of stay (7.3 ± 7.3 vs. 5.9 ± 2.7 p: .09), post-op atrial fibrillation (AF) (16.3% vs. 8.5% p: .20).Conclusions: New onset LBBB was frequent conduction problem post TAVR and one-third of patients with new onset LBBB persisted at discharge. New LBBB after TAVR was associated with a higher risk of PPM implantation during the index hospitalisation but not after discharge. Our findings suggest that early PPM implantation for post-TAVR LBBB is not indicated without complete or high degree AV block. Further research is required to identify the patients with new LBBB who would progress to advanced AV block or heart failure.

[Transcatheter aortic valve implantation and conduction disturbances]

Transcatheter aortic valve implantation (TAVI) is currently becoming the treatment of choice for patients with calcific aortic stenosis. Despite several technical improvements, the incidence of conduction disturbances has not diminished and remains TAVI's major complication. These disturbances include the occurrence of left bundle branch block and/or high-grade atrioventricular block often requiring pacemaker implantation. The proximity of the aortic valve to the conduction system (conduction pathways) accounts for the occurrence of these complications. Several factors have been identified as carrying a high risk of conduction disturbances like the presence of pre-existing right bundle branch block, the type of valve implanted, the volume of aortic and mitral calcifications, the size of the annulus and the depth of valve implantation. Left bundle branch block is the most frequent post TAVI conduction disturbance. Whereas the therapeutic strategy for persistent complete atrioventricular block is simple, it becomes complex in the presence of fluctuating changes in PR interval and left bundle branch block duration. The QRS width threshold value (150-160 ms) indicative of the need for pacemaker implantation is still being debated. Although there are currently no recommendations regarding the management of these conduction disturbances, the extension of TAVI indications to patient at low surgical risk calls for a standardization of our practice. However, a decision algorithm was recently proposed by a group of experts composed of interventional cardiologists, electrophysiologists and cardiac surgeons. There are still uncertainties about the appropriate timing of pacemaker implantation and the management of new onset left bundle branch block.

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.

Update in Heart Rhythm Abnormalities and Indications for Pacemaker After Transcatheter Aortic Valve Implantation

Objective: Rhythm abnormalities following transcatheter aortic valve implantation (TAVI) and indications for permanent pacemaker implantation (PPI) were reviewed, which aren't well established in the current guidelines. New left bundle branch block and atrioventricular block are the most common electrocardiographic changes after TAVI. PPI incidence ranges from 9-42% for self-expandable and 2.5-11.5% for balloon expandable devices. Not only anatomical variations in conduction system have an important role in conduction disorders, but different valve characteristics and their relationship with cardiac structures as well. Previous right bundle branch block has been confirmed as one of the most significant predictors for PPI.

Relation of Left Ventricular Fractional Shortening to Needfor Permanent Pacemaker After Transcatheter AorticValve Implantation

Transcatheter aortic valve implantation (TAVI) can potentially alter conduction system function due to the mechanical force applied to the conduction system by the proximal edge of the valve, particularly the CoreValve. Some reasons for post-TAVI advanced atrioventricular block have been identified. We investigated whether the degree of the motion of the basal left ventricular (LV) walls impacted the development of advanced atrioventricular block post-TAVI. A total of 407 patients (82.1 ± 6.2 years) without prior permanent pacemakers (PPMs) underwent TAVI using CoreValve (70%) or Edwards-SAPIEN (30%) prosthetic devices. The LV fractional shortening (FS) of the basal segments was measured in each patient, and the association between FS and PPM requirement, or new-onset left bundle branch block (LBBB) was evaluated. During hospitalization, 64 patients (15.7%) required PPM implantation, and 128 patients (31.4%) required PPM implantation or developed new LBBB. Independent predictors of PPM implantation included preprocedural right bundle branch block, CoreValve prosthetic device, valve implantation depth, and FS. Patients with high FS (≥40%, upper tertile) had a 2.5-fold increased risk of PPM implantation (p = 0.004) and a 1.8-fold increased risk of PPM or new LBBB (p = 0.020). Every 10% increment in FS was consistently associated with an adjusted 42% increased risk of PPM implantation (p = 0.015) and with an adjusted 43% increased risk of PPM implantation or new LBBB (p = 0.005). Thus, in our cohort, LV FS was independently associated with the need for PPM implantation during hospitalization. Hence, this simple echocardiographic measure can be used to identify patients who are at risk after TAVI.

TAVI and Post Procedural Cardiac Conduction Abnormalities

Transcatheter aortic valve implantation (TAVI) is a worldwide accepted alternative for treating patients at intermediate or high risk for surgery. In recent years, the rate of complications has markedly decreased except for new-onset atrioventricular and intraventricular conduction block that remains the most common complication after TAVI. Although procedural, clinical, and electrocardiographic predisposing factors have been identified as predictors of conduction disturbances, new strategies are needed to avoid such complications, particularly in the current TAVI era that is moving quickly toward the percutaneous treatment of low-risk patients. In this article, we will review the incidence, predictive factors, and clinical implications of conduction disturbances after TAVI.

Conduction disorders using the Evolut R prosthesis compared with the CoreValve: has anything changed?

Aim

We compared early postprocedural and midterm evolution of atrioventricular and intraventricular conduction disorders following implantation of the new generation Evolut R (ER) prosthesis in comparison with the previous generation CoreValve (CV) system using routinely recorded ECG up to 6-month follow-up.

Methods

All consecutive patients treated by transcathether aortic valve implantation (TAVI) using the Medtronic self-expanding devices for symptomatic severe aortic stenosis in a single centre between October 2011 and February 2016 were considered for inclusion. ECGs recorded at baseline, day 1 after TAVI, discharge and 6 months were retrospectively analysed. At each time-point, intrinsic rhythm, PR interval, QRS axis and duration, and atrioventricular and intraventricular conduction were analysed. Atrioventricular and intraventricular conduction following TAVI at discharge and at 6 months were compared intrasubject at the different time intervals and between patients receiving the ER versus the CV prosthesis.

Results

Among the 113 patients included in the analysis (51% female, 83.3±6.2 years), 60 (53%) patients received the CV and 53 (47%) patients received the ER. Compared with patients in the CV group, those in the ER group had a lower Society of Thoracic Surgeons score (6.3±3.1vs 4.8±3.6, P=0.02). Patients in the ER group in comparison with those in the CV group more frequently had postprocedural PR interval (57%vs23%, respectively, P=0.004) and QRS prolongation (76%vs50%, P=0.03) at discharge. Incidence of complete atrioventricular block was similar between both groups (9%vs18%, P=0.3) up to 6-month follow-up. No difference in term of new left bundle branch block (LBBB) (34%vs28%, P=0.8) or permanent pacemaker implantation rates (32.1%vs31.7%, P=1.0) was reported.

Conclusions

Patients with the ER had greater postprocedural atrioventricular and intraventricular conduction delays than those with the CV at discharge, with however similar incidence of high-degree atrioventricular block, new LBBB and permanent pacemaker implantation up to 6-month follow-up.

Conduction abnormalities after transcatheter aortic valve implantation

In the last few years, transcatheter aortic valve implantation (TAVI) has become an alternative procedure in patients with severe aortic stenosis and high risk for surgical aortic replacement. Due to the anatomic correlation between aortic valve structure and conduction system of the heart, one of the most common complications after TAVI is conduction system disturbances which including bundle branch block, complete heart block and need for permanent pacemaker implantation. Although these disturbances are usually not lethal, they may have a great influence on patients' state and long term-survival. Several risk factors for conduction disturbances have been identified which including age, anatomy of the heart, periprocedural factors, type of implanted valve, preexisting abnormalities and comorbidities. As this technique becomes more familiar to physicians, patients should be carefully screened for risk factors for the development of conduction abnormalities after TAVI in order to provide effective prevention and proper treatment.

Permanent Pacing After Transcatheter Aortic Valve Implantation: Incidence, Predictors and Evolution of Left Ventricular Function

Background

Transcatheter aortic valve implantation (TAVI) is a well-established procedure; however, atrioventricular block requiring permanent pacemaker implantation (PPI) is a common complication.

Objectives

To determine the incidence, predictors and clinical outcomes of PPI after TAVI, focusing on how PPI affects left ventricular ejection fraction (LVEF) after TAVI.

Methods

The Brazilian Multicenter TAVI Registry included 819 patients submitted to TAVI due to severe aortic stenosis from 22 centers from January/2008 to January/2015. After exclusions, the predictors of PPI were assessed in 670 patients by use of multivariate regression. Analysis of the ROC curve was used to measure the ability of the predictors; p < 0.05 was the significance level adopted.

Results

Within 30 days from TAVI, 135 patients (20.1%) required PPI. Those patients were older (82.5 vs. 81.1 years; p = 0.047) and mainly of the male sex (59.3% vs 45%; p = 0.003). Hospital length of stay was longer in patients submitted to PPI (mean = 15.7 ± 25.7 vs. 11.8 ± 22.9 days; p < 0.001), but PPI affected neither all-cause death (26.7% vs. 25.6%; p = 0.80) nor cardiovascular death (14.1% vs. 14.8%; p = 0.84). By use of multivariate analysis, the previous presence of right bundle-branch block (RBBB) (OR, 6.19; 3.56-10.75; p ≤ 0.001), the use of CoreValve^® prosthesis (OR, 3.16; 1.74-5.72; p ≤ 0.001) and baseline transaortic gradient > 50 mm Hg (OR, 1.86; 1.08-3.2; p = 0.025) were predictors of PPI. The estimated risk of PPI ranged from 4%, when none of those predictors was present, to 63%, in the presence of all of them. The model showed good ability to predict the need for PPI: 0.69 (95%CI: 0.64 - 0.74) in the ROC curve. The substudy of 287 echocardiograms during the 1-year follow-up showed worse LVEF course in patients submitted to PPI (p = 0.01).

Conclusion

BRD prévio, gradiente aórtico médio > 50 mmHg e CoreValve® são preditores independentes de implante de MPD pós-TAVI. Ocorreu implante de MPD em aproximadamente 20% dos casos de TAVI, o que prolongou a internação hospitalar, mas não afetou a mortalidade. O implante de MPD afetou negativamente a FEVE pós-TAVI.

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.