New-onset Left Bundle Branch Block Research Articles

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

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

Comparison of Down Sizing Strategy (HANGZHOU Solution) and Standard Annulus Sizing Strategy in type 0 bicuspid aortic stenosis patients undergoing transcatheter aortic valve replacement: Rationale and design of a randomized clinical trial

BackgroundThere has not been a consensus on the prothesis sizing strategy in type 0 bicuspid aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). Modifications to standard annular sizing strategies might be required due to the distinct anatomical characteristics. We have devised a Down Sizing Strategy for TAVR using a self-expanding valve specifically for patients with type 0 bicuspid AS. The primary aim of this study is to compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy in TAVR for patients with type 0 bicuspid AS. Trial designIt is a prospective, multi-center, superiority, single-blinded, randomized controlled trial comparing the Down Sizing and Standard Annulus Sizing Strategy in patients with type 0 bicuspid aortic stenosis undergoing transcatheter aortic valve replacement. Eligible participants will include patients with severe type 0 bicuspid AS, as defined by criteria such as mean gradient across aortic valve ≥40 mmHg, peak aortic jet velocity ≥4.0 m/s, aortic valve area (AVA) ≤1.0 cm², or AVA index ≤0.6 cm2/m2. These patients will be randomly assigned, in a 1:1 ratio, to either the Down Sizing Strategy group or the Standard Sizing Strategy group. In the Down Sizing Strategy group, a valve one size smaller will be implanted if the “waist sign” manifests along with less than mild regurgitation during balloon pre-dilatation. The primary end point of the study is a composite of VARC-3 defined device success, absence of both permanent pacemaker implantation due to high-degree atrioventricular block and new-onset complete left bundle branch block. ConclusionThis study will compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy and provide valuable insights into the optimal approach for sizing in TAVR patients with type 0 bicuspid AS. We hypothesize that the Down Sizing Strategy will demonstrate superiority when compared to the Standard Annulus Sizing Strategy. (Down Sizing Strategy (HANGZHOU Solution) vs Standard Sizing Strategy TAVR in Bicuspid Aortic Stenosis (Type 0) (TAILOR-TAVR), NCT05511792)

Conduction system disease management in patients candidate and/or treated for the aortic valve disease: an Italian Survey promoted by Italian Association of Arrhythmology and Cardiac Pacing (AIAC).

Conduction system disorders represent a frequent complication in patients undergoing surgical (surgical aortic valve replacement, SAVR) or percutaneous (transcatheter aortic valve implantation, TAVI) aortic valve replacement. The purpose of this survey was to evaluate experienced operators approach in this clinical condition. This survey was independently conducted by the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) and it consisted of 24 questions regarding the respondents' profile, the characteristics of participating centres, and conduction disease management in different scenarios. Fifty-five physicians from 55 Italian arrhythmia centres took part in the survey. Prophylactic pacemaker implantation is rare. In case of persistent complete atrioventricular block (AVB), 49% and 73% respondents wait less than one week before implanting a definitive pacemaker after SAVR and TAVI, respectively. In case of second degree AVB, the respondents wait some days more for definitive implantation. Respondents consider bundle branch blocks, in particular pre-existing left bundle branch block (LBBB), the worst prognostic factors for pacemaker implantation after TAVI. The implanted valve type is considered a relevant element to evaluate. In patients with new-onset LBBB and severe/moderate left ventricular systolic dysfunction, respondents would implant a biventricular pacemaker in 100/55% of cases, respectively. Waiting time before a definitive pacemaker implantation after aortic valve replacement has reduced compared to the past, and it is anticipated in TAVI vs. SAVR. Bundle branch blocks are considered the worse prognostic factor for pacemaker implantation after TAVI. The type of pacemaker implanted in new-onset LBBB patients without severe left ventricular systolic dysfunction is heterogeneous.

Predictors for new-onset conduction block in patients with pure native aortic regurgitation after transcatheter aortic valve replacement with a new-generation self-expanding valve (VitaFlow Liberty™): a retrospective cohort study

BackgroundNew-generation self-expanding valves can improve the success rate of transcatheter aortic valve replacement (TAVR) for severe pure native aortic regurgitation (PNAR). However, predictors of new-onset conduction block post-TAVR using new-generation self-expanding valves in patients with PNAR remain to be established. Therefore, this study aimed to identify predictors of new-onset conduction block post-TAVR using new-generation self-expanding valves (VitaFlow Liberty™) in patients with PNAR.MethodsIn this retrospective cohort study, patients were categorized into pacemaker and non-pacemaker groups based on their need for new postoperative permanent pacemaker implantation (PPI). Based on the postoperative presence of either new-onset complete left bundle branch block (cLBBB) or high-grade atrioventricular block (AVB), patients were further classified into conduction disorder and non-conduction disorder groups. Laboratory, echocardiographic, computed tomography, preoperative and postoperative electrocardiography, and procedural and clinical data were collected immediately after TAVR and during hospitalization and compared between the groups. Multivariate logistic regression analysis was performed incorporating the significant variables from the univariate analyses.ResultsThis study examined 68 consecutive patients with severe PNAR who underwent TAVR. In 20 patients, a permanent pacemaker was fitted postoperatively. Multivariate logistic regression analysis revealed an association between the need for postoperative PPI and preoperative complete right bundle branch block (cRBBB) or first-degree AVB, as well as a non-tubular left ventricular outflow tract (LVOT). In addition, valve implantation depth and angle of aortic root were independent predictors of new-onset cLBBB or high-grade AVB developing post-TAVR. The predictive value of valve implantation depth and angle of aortic root was further supported by receiver operating characteristic curve analysis results.ConclusionsIn patients with PNAR undergoing TAVR using self-expanding valves, preoperative cRBBB or first-degree AVB and a non-tubular LVOT were indicators of a higher likelihood of PPI requirement. Moreover, deeper valve implantation depth and greater angle of aortic root may be independent risk factors for new-onset cLBBB or high-grade AVB post-TAVR. Valve implantation depth and angle of aortic root values may be used to predict the possibility of new cLBBB or high-grade AVB post-TAVR.

Relative longitudinal strain apical sparing pattern and low albumin as detrimental factors of cardiovascular outcome after transcatheter aortic valve replacement

Abstract Background Relative apical sparing pattern (RASP) of longitudinal strain (LS), a typical echocardiographic feature of cardiac amyloidosis, is associated with cardiac death or heart failure admission in severe aortic stenosis (AS) patients, and associated with all-cause death among elderly patients with severe AS undergoing transcatheter aortic valve replacement (TAVR). Purpose Present study aimed to explore clinical and echocardiographic determinants of short-term and long-term CV outcome (including CV death and CV hospitalization) in symptomatic severe AS patients after TAVR, and to assess the independent and incremental prognostic value of RASP on CV outcome in TAVR patients. Methods This retrospective study comprised 598 consecutive AS patients underwent TAVR (mean age 81.7±5.7 years, 48.7% male). Pre-operative clinical and echocardiography data, including 2D speckle tracking imaging indexes, were analyzed. Clinical outcomes included CV death and procedure related complications at 30 days, 1 year, and at 2 years after TAVR. Results Relative apical sparing pattern (RASP) of longitudinal strain (LS) was defined as ≥3 LV wall segments with the apical-basal LS ratio &amp;gt;3.0. The prevalence of RASP was 19.2%. Compared with patients without RASP, patients with RASP were associated with higher risk of acute kidney injury (AKI, 10.4% vs. 3.3%, P=0.001) and new-onset left bundle branch block (LBBB) after TAVR (17.4% vs. 6.8%, P&amp;lt;0.001) and higher 2-year CV mortality (22.6% vs. 9.9%, P&amp;lt;0.001, Figure 1) after TAVR. Lower pre-procedural albumin level and RASP were identified as independent determinants of increased 2-year CV mortality (RASP: HR=2.178, P=0.002; albumin&amp;lt;4.0g/dl: HR= 2.548, P&amp;lt;0.001), regardless of TAVR approach and EuroSCORE II. After adjustment, the addition of RASP significantly improved prognostic power of a model including clinical variables and low albumin level for predicting 2-year CV death (χ2 from 28.179 to 40.699, P=0.001, Figure 2). Conclusion RASP is a significant determinant of AKI and new-onset LBBB after TAVR. RASP together with low pre-procedural albumin level serve as the strongest determinants of increased risk of 2-year CV mortality after TAVR.Figure 1Figure 2

Left ventricular afterload reduction by transcatheter aortic valve implantation acutely alleviates right ventricular pacing-induced left ventricular dysfunction in patients with aortic stenosis

Abstract Introduction In patients with left bundle branch block (LBBB) cardiac function has been found to be particularly sensitive to alterations in left ventricular (LV) afterload. Nevertheless, whether the detrimental hemodynamic effect of right ventricular pacing (RVP)-induced electromechanical dyssynchrony on LV function is also associated with afterload dependency, has not been investigated yet. Purpose Hence, in the current study we sought to examine the acute effect of RVP on LV function in patients with aortic stenosis (AS) before (with elevated afterload) and after (without elevated afterload) transcatheter aortic valve implantation (TAVI). Methods Patients with a previously implanted permanent pacemaker (PM) and significant AS referred for TAVI at our heart and vascular center university were screened for this observational study. Only those patients who had an intrinsic, regular, narrow QRS or right bundle branch block (RBBB) morphology rhythm were included. From 2022 March to 2023 February, nine patients with a DDD PM (with sick sinus syndrome and maintained AV conduction) and four patients with a VVI PM (with atrial fibrillation and complete AV block but stable junctional escape rhythm) were enrolled. Following TAVI, four patients were excluded due to the development of new-onset persistent LBBB. Transthoracic conventional and advanced echocardiography and non-invasive blood pressure monitoring were performed immediately before TAVI and on the second postoperative day. The measurements were carried out during intrinsic QRS rhythm and during frequency-matched RVP as well. Global longitudinal strain was determined by speckle-tracking echocardiography, then using LV pressure curves estimated from systolic blood pressure and mean aortic gradient, global myocardial work index (GMWI) was calculated to assess LV contractility. Results Mean aortic gradient was decreased after TAVI (40.2±3.6 vs. 6.7±1.3mmHg before vs. after TAVI, P&amp;lt;0.001) indicating successful reduction of LV afterload. Compared to the intrinsic QRS rhythm, RVP decreased GMWI before TAVI (GMWI: 1967±206 vs. 1240±174mmHg% intrinsic QRS vs. RVP, P&amp;lt;0.001) and after TAVI (GMWI: 1399±149 vs. 1020±121mmHg% intrinsic QRS vs. RVP, P=0.019) as well. Nevertheless, the extent of RVP-induced LV contractility impairment (expressed as ΔGMWI) was significantly alleviated after pressure unloading therapy (ΔGMWI: -37.1±6.6 vs. -24.5±7.8% before TAVI vs. after TAVI, P=0.024). Conclusion Our preliminary results indicate that RVP-induced LV dysfunction is afterload dependent. Hence, in patients with AS and a high percentage of RVP, TAVI might entail substantial functional improvement.

Abstract 17172: Paradoxical QRS Narrowing After Transcatheter Aortic Valve Replacement Concealing New Left Bundle Branch Block

Introduction: Left bundle branch block (LBBB) after transcatheter aortic valve replacement (TAVR) is common and is a risk factor for high-grade atrioventricular (AV) block. We report a case of paradoxical QRS narrowing after TAVR in a patient with pre-existing incomplete right bundle branch block (iRBBB). Such QRS narrowing, masquerading as improved AV conduction, may conceal the development of new LBBB. Case Presentation: An 81-year-old man with severe aortic stenosis underwent TAVR with a 29mm Medtronic Evolut transcatheter self-expanding bioprosthetic valve. Post-operative TEE showed a well-seated valve without paravalvular leak. Preoperative ECG demonstrated sinus rhythm, 1 st degree AV delay (230 ms), and iRBBB (QRS 110 ms) (Fig. 1A). Immediately after TAVR, ECG showed a narrowed QRS (90 ms) with normal morphology (Fig. 1B). A narrowed QRS was sustained on post-operative day 2, with prolongation of the PR interval (260 ms; Fig. 1C). Electrophysiology study (EPS) showed a prolonged HV interval (65 ms) but no inducible block (Fig. 1D), and an implantable loop recorder (ILR) was placed. Discussion: Damage to the infranodal cardiac conduction system after TAVR is common, and approximately 15% of post-TAVR patients require pacemaker, with a higher occurrence in self-expanding valves as compared to balloon-expandable valves. Pre-existing RBBB as well as new-onset LBBB after TAVR increase the risk for heart block. Here, QRS normalization of an iRBBB concealed the development of new LBBB, by way of balanced delay in both the right and left bundles. This balanced delay is evident in the slightly longer PR interval post-operatively. Such a finding may be falsely reassuring and requires increased scrutiny (such as EPS and ILR placement). Conclusion: This case illustrates that paradoxical normalization of AV conduction following TAVR may belie an increased risk of high-grade AV block. Structural heart teams should be aware of this potential post-operative complication.

Cardiac Death After Transcatheter Aortic Valve Replacement With Contemporary Devices

BackgroundThe burden of cardiac death after transcatheter aortic valve replacement (TAVR), particularly from advanced heart failure (HF) and sudden cardiac death (SCD), remains largely unknown. ObjectivesThis study sought to evaluate the incidence and predictors of SCD and HF-related death in TAVR recipients treated with newer-generation devices. MethodsThis study included a total of 5,421 consecutive patients who underwent TAVR with newer-generation devices using balloon (75.7%) or self-expandable (24.3%) valves. ResultsAfter a median follow-up of 2 (IQR: 1-3) years, 976 (18.0%) patients had died, 50.8% from cardiovascular causes. Advanced HF and SCD accounted for 11.6% and 7.5% of deaths, respectively. Independent predictors of HF-related death were atrial fibrillation (HR: 2.17; 95% CI: 1.47-3.22; P < 0.001), prior pacemaker (HR: 1.79; 95% CI: 1.10-2.92; P = 0.01), reduced left ventricular ejection fraction (HR: 1.08 per 5% decrease; 95% CI: 1.01-1.14; P = 0.02), transthoracic approach (HR: 2.50; 95% CI: 1.37-4.55; P = 0.003), and new-onset persistent left bundle branch block (HR: 1.85; 95% CI: 1.14-3.02; P = 0.01). Two baseline characteristics (diabetes, HR: 1.81; 95% CI: 1.13-2.89; P = 0.01; and chronic kidney disease, HR: 1.72; 95% CI: 1.02-2.90; P = 0.04) and 3 procedural findings (valve in valve, HR: 2.17; 95% CI: 1.01-4.64; P = 0.04; transarterial nontransfemoral approach, HR: 2.23; 95% CI: 1.23-4.48; P = 0.01; and periprocedural ventricular arrhythmia, HR: 7.19; 95% CI: 2.61-19.76; P < 0.001) were associated with an increased risk of SCD after TAVR. ConclusionsAdvanced HF and SCD accounted for a fifth of deaths after TAVR in contemporary practice. Potentially treatable factors leading to increased risk of HF deaths and SCD were identified, such as arrhythmia/dyssynchrony factors for HF and valve-in-valve TAVR or periprocedural ventricular arrhythmias for SCD.

Conduction Disturbance After Transcatheter Aortic Valve Implantation With Self- or Balloon-Expandable Valve According to the Implantation Depth

Membranous septum (MS) length, in conjunction with implantation depth (ID), is known as a determinant of conduction disturbance (CD) after transcatheter aortic valve implantation (TAVI). However, its impact might be dissimilar among valve types because each valve has a different platform. This study sought to investigate the different impacts of ID and MS length on the new-onset CD between ACURATE neo and SAPIEN 3. This study included patients without a previous permanent pacemaker implantation who underwent TAVI with ACURATE neo and SAPIEN 3 and divided them into 2 groups based on the ID according to MS length (deep and shallow implantation group). Deep implantation was defined as transcatheter heart valve implantation deeper than MS length. The primary endpoint was new-onset CD (new permanent pacemaker implantation or new-onset complete left bundle branch block). A total of 688 patients (deep implantation: n=373, shallow implantation: n=315) were identified as a study cohort. New-onset CD developed more frequently in the deep implantation group (16.6% vs 7.0%; p=0.0001). Deep implantation was revealed as a predictor of new-onset CD. Moreover, deep implantation was significantly associated with new-onset CD after SAPIEN 3 implantation but not after ACURATE neo. Among patients with MS shorter than 2mm, ACURATE neo was superior in terms of avoiding new-onset CD. In conclusion, the deep implantation was associated with new-onset CD after TAVI with SAPIEN 3 but not with ACURATE neo. These results may impact device selection in patients with a preexisting high risk of CD.

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.

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

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. 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 30days after the procedure and/or the need for PPM diagnosed within 1year 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. Of 211 patients (41.7% men; median 81years), 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 ± 2.6mm; 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). 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. 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. • 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.

Ventricular pacing burden in patients with left bundle branch block after transcatheter aortic valve replacement therapy.

Electrophysiological testing has been proposed in the latest European Society of Cardiology (ESC) guidelines for cardiac pacing to identify left bundle branch block (LBBB) patients with infrahisian conduction delay (IHCD) after transcatheter aortic valve replacement (TAVR). While in general IHCD is defined by a His-ventricular (HV) interval of >55 ms, a cut-off of ≥70 ms to trigger pacemaker (PM) implantation has been proposed in the latest ESC guidelines. The ventricular pacing (VP) burden during follow-up in such patients is largely unknown. As such, we aimed to assess the VP burden during follow-up of patients receiving PM therapy for LBBB after TAVR based on an HV interval > 55 ms and ≥70 ms. All patients with new-onset or pre-existing LBBB after undergoing TAVR at a tertiary referral center underwent EP testing the day after TAVR. In patients with a prolonged HV interval (>55 ms), PM implantation was performed by a trained electrophysiologist in a standardized fashion. All devices were programmed to avoid unnecessary VP by specific algorithms (e.g., AAI-DDD). 701 patients underwent TAVR at the University Hospital of Basel. One hundred seventy-seven patients presented with new-onset or pre-existing LBBB the day following TAVR and underwent EP testing. An HV interval > 55 ms was found in 58 patients (33%) and an HV interval ≥ 70 ms in 21 patients (12%). 51 patients (mean age 84 ± 6.2 years, 45% women) agreed to receive a PM, out of which 20 (39%) patients had an HV Interval over 70 ms. Atrial fibrillation was present in 53% of the patients. A dual chamber PM was implanted in 39 (77%), and a single chamber PC in 12 (23%) patients, respectively. Median follow-up was 21 months. The median VP burden overall was 3%. The median VP burden was not significantly different between patients with an HV ≥ 70 ms (6.5 [0.8-52]) and those with an HV between 55 and 69 ms (2 [0-17], p = .23). 31% of patients demonstrated a VP burden < 1%, 27% 1%-5% and 41% > 5%. The median HV intervals in patients with VP burdens < 1%, 1%-5% and >5% were 66 (IQR 62-70) ms, 66 (IQR 63-74) ms and 68 (IQR 60-72) ms, respectively, p = .52. When only assessing patients with an HV interval 55-69 ms, 36% demonstrated a VP burden of <1%, 29% of 1%-5% and 35% of >5%. In patients with an HV Interval ≥ 70 ms, 25% demonstrated a VP burden < 1%, 25% of 1%-5% and 50% of >5% %, p = .64 (Figure). In patients with LBBB after TAVR and IHCD defined by an HV interval > 55 ms, VP burden is relevant in a non-negligible amount of patients during follow-up. Further studies are warranted to define the optimal cut-off value for the HV interval or to develop risk models incorporating HV measurements and other risk factors to trigger PM implantation in patients with LBBB after TAVR.

New-Onset Left Bundle Branch Block With ST Elevation After Minimally Invasive Aortic Valve Replacement: Differential Diagnosis

New-Onset Left Bundle Branch Block With ST Elevation After Minimally Invasive Aortic Valve Replacement: Differential Diagnosis

PO-04-017 'LEFT' BROKEN AFTER EXERCISE: A CASE OF PAINFUL LBBB SYNDROME SUCCESSFULLY TREATED WITH LEFT BUNDLE BRANCH AREA PACING

The leading causes of new-onset left bundle branch block (LBBB) include coronary artery disease, hypertension, and cardiomyopathies. However, when the LBBB occurs in the absence of ischemia, in a rate-dependent manner, usually with exertion, it constitutes a painful left bundle branch block. Although there are multiple case reports of this entity, the mechanism, pathophysiology, and treatment are not well defined. We intend to raise awareness of this syndrome and highlight our unique treatment approach. NA A 57-year-old male presented to the cardiology clinic with exertional chest pain and palpitations. He underwent an exercise ECG test, surprisingly on stage 2 of Bruce protocol, at around a heart rate of 116 bpm; he started developing LBBB on every other beat. At a heart rate of 125 bpm, he developed persistent LBBB associated with similar symptoms, both of which persisted in the recovery phase (Figure 1). His Echocardiogram was normal. Invasive coronary angiography revealed normal coronaries. Previous case reports have shown that cardiac rehabilitation helps to delay the onset of LBBB to a higher heart rate; however, he opted for pacemaker implantation as he had severe exercise limitations. He underwent a biventricular-implantable pacemaker with right atrial, left bundle branch area, and coronary sinus (CS) left ventricular (LV) leads. The pacemaker was programmed DDD60 with a rate adaptive AV interval with a start rate of 80 bpm. This would enable the LBB area pacing above a heart rate of 80 bpm. Within one week of implantation, the patient had a complete resolution of his symptoms. A cardiopulmonary exercise test to assess VO2 with pacing programmed off and then on is scheduled as part of the follow-up. The symptoms of the painful LBBB syndrome can be quite severe, resulting in physical and psychological debilitation. Treatment with a physical exercise regimen has been successful as it delays the LBBB onset to a higher heart rate. However, the patient loses the benefit once they stop exercising. A definitive solution is a pacemaker; there are multiple case reports of His bundle and right ventricular pacing, which successfully treated this syndrome. In this case, we used a unique approach of pacing just the LBBB area; in addition, a CS LV lead was placed, which could be used for an earlier activation of the LV if the patient needs that in the future.

Técnica de superposición de cúspides en TAVI con el sistema autoexpandible Portico FlexNav

Introduction and objectivesThe cusp overlap technique (COT) has been proposed to reduce conduction disturbances (CD) after transcatheter aortic valve implantation (TAVI) with self-expanding supra-annular devices, but there are scarce data on COT with intra-annular valves. The aim of this study was to determine whether the use of the COT during Portico implantation results in higher valve implantation and lower rates of CD. MethodsWe included 85 patients undergoing TAVI with the Portico FlexNav system: 43 retrospective patients using the standard 3-cusp view and 42 prospective patients with the COT. Primary endpoints were implantation depth and new-onset CD (composite outcome of new-onset left bundle branch block and new permanent pacemaker implantation). ResultsCOT resulted in a higher implantation depth (noncoronary cusp: 4.9±3.9 vs 7.4±3.0; P=.005) and lower new-onset CD (31.0% vs 58.1%; P=.012), with a tendency toward a lower need for permanent pacemaker implantation (14.3% vs 30.2%, P=.078; 7.7% vs 31.0%; P=.011 in patients without pre-existing right bundle branch block). Transvalvular aortic gradients were slightly lower with COT (8.7±3.7 vs 11.0±6.1; P=.044). There were no differences in technical success or major procedure-related complications. On multivariate analysis, COT use was associated with a lower risk of new-onset CD. ConclusionsUse of the COT during Portico implantation is feasible and facilitates a higher valve implant, which in turn may help to reduce rates of new-onset CD.

Vulnerability of the ventricular conduction axis during transcatheter aortic valvar implantation: A translational pathologic study.

The ventricular components of the conduction axis remain vulnerable following transcatheter aortic valvar replacement. We aimed to describe features which may be used accurately by interventionalists to predict the precise location of the conduction axis, hoping better to avoid conduction disturbances. We scanned eight normal adult heart specimens by 3T magnetic resonance, using the images to simulate histological sections in order accurately to place the conduction axis back within the heart. We then used histology, tested in two pediatric hearts, to prepare sections, validated by the magnetic resonance images, to reveal the key relationships between the conduction axis and the aortic root. The axis was shown to have a close relationship to the nadir of the right coronary leaflet, in particular when the aortic root was rotated in counterclockwise fashion. The axis was more vulnerable in the setting of a narrow inferoseptal recess, when the inferior margin of the membranous septum was above the plane of the virtual basal ring, and when minimal myocardium was supporting the right coronary sinus. The features identified in our study are in keeping with the original description provided by Tawara, but at variance with more recent accounts. They suggest that the vulnerability of the axis during transcatheter valvar replacement can potentially be inferred on the basis of knowledge of the position of the aortic root within the ventricular base. If validated by clinical studies, our findings may better permit avoidance of new-onset left bundle branch block following transcatheter aortic valvar replacement.

Cusp-overlap technique during TAVI using the self-expanding Portico FlexNav system

Introduction and objectivesThe cusp overlap technique (COT) has been proposed to reduce conduction disturbances (CD) after transcatheter aortic valve implantation (TAVI) with self-expanding supra-annular devices, but there are scarce data on COT with intra-annular valves. The aim of this study was to determine whether the use of the COT during Portico implantation results in higher valve implantation and lower rates of CD. MethodsWe included 85 patients undergoing TAVI with the Portico FlexNav system: 43 retrospective patients using the standard 3-cusp view and 42 prospective patients with the COT. Primary endpoints were implantation depth and new-onset CD (composite outcome of new-onset left bundle branch block and new permanent pacemaker implantation). ResultsCOT resulted in a higher implantation depth (noncoronary cusp: 4.9±3.9 vs 7.4±3.0; P=.005) and lower new-onset CD (31.0% vs 58.1%; P=.012), with a tendency toward a lower need for permanent pacemaker implantation (14.3% vs 30.2%, P=.078; 7.7% vs 31.0%; P=.011 in patients without pre-existing right bundle branch block). Transvalvular aortic gradients were slightly lower with COT (8.7±3.7 vs 11.0±6.1; P=.044). There were no differences in technical success or major procedure-related complications. On multivariate analysis, COT use was associated with a lower risk of new-onset CD. ConclusionsUse of the COT during Portico implantation is feasible and facilitates a higher valve implant, which in turn may help to reduce rates of new-onset CD.

Prediction of conduction disturbances in patients undergoing transcatheter aortic valve replacement

AimTranscatheter aortic valve replacement (TAVR) can cause intraventricular conduction disturbances (ICA), particularly left bundle branch block (BBB) and high-degree atrioventricular block (HAVB). The aim of this study was to investigate clinical, anatomical, procedural, and electrophysiological parameters predicting ICA after TAVR.MethodsPatients with severe aortic stenosis (n = 203) without pacing devices undergoing TAVR with a self-expanding (n = 103) or balloon-expanding (n = 100) valve were enrolled. Clinical and anatomical parameters, such as length of the membranous septum (MS) and implantation depth, were assessed. His-ventricular interval (HVi) before and after implantation was determined. 12-lead-electrocardiograms (ECG) before, during and after 3 and 30 days after TAVR were analyzed for detection of any ICA.ResultsAmong 203 consecutive patients (aortic valve area 0.78 ± 0.18 cm2, age 80 ± 6 years, 54% male, left ventricular ejection fraction 52 ± 10%), TAVR led to a significant prolongation of infranodal conduction in all patients from 49 ± 10 ms to 59 ± 16 ms (p = 0.01). The HVi prolongation was independent of valve types, occurrence of HAVB or ICA. Fifteen patients (7%) developed HAVB requiring permanent pacemaker (PPM) implantation and 63 patients (31%) developed ICA within 30 days. Pre-existing BBB (OR 11.64; 95% CI 2.87–47.20; p = 0.001), new-onset left BBB (OR 15.72; 95% CI 3.05–81.03; p = 0.001), and diabetes mellitus (OR 3.88; 95% CI 1.30–15.99; p = 0.02) independently predicted HAVB requiring PPM. Neither pre-existing right BBB, a prolonged postHVi, increases in PR duration, any of the TAVR implantation procedural and anatomic nor echocardiographic characteristics were predictive for later HAVB.ConclusionsNew-onset left BBB and diabetes mellitus independently predicted HAVB requiring PPM after TAVR and helped to identify patients at risk. Electrophysiologic study (EPS) of atrioventricular conduction was neither specific nor predictive of HAVB and can be skipped.Trial registration numberNCT04128384 (https://www.clinicaltrials.gov).Graphical abstract

Reduction of permanent pacemaker implantation by using the cusp overlap technique in transcatheter aortic valve replacement: a meta-analysis

BackgroundThe need for permanent pacemaker (PPM) implantation is a common complication after transcatheter aortic valve replacement (TAVR). Deep implantation position is a risk factor for PPM implantation. Thus, in the field of self-expandable (SE) transcatheter heart valves (THV) cusp overlap projection (COP) technique was implemented to reduce parallax, allowing a more precise guidance of implantation depth.AimsThis meta-analysis aims to report the outcome of patients undergoing TAVR with SE THV using COP versus conventional implantation technique (CIT).MethodsSystematical search in MEDLINE and EMBASE yielded five observational controlled studies comparing both implantation techniques for the SE Evolut prosthesis (Medtronic Intern. Ltd., CA, USA) and fulfilling the inclusion criteria for meta-analysis.ResultsTotally, 1227 patients were included, comprising 641 who underwent COP and 586 CIT TAVR. Incidence of post-procedural need for PPM implantation was significantly lower in COP group (9.8% vs 20.6%; OR = 0.43; p < 0.00001). This was accompanied by significantly higher implantation position in COP group (mean difference distance from distal end of the intraventricular portion of the THV to the non-coronary cusp (NCC): − 1.03 mm; p = 0.00001). Incidence of new-onset left bundle branch block did not differ. Regarding procedural and 30-day mortality, technical success, post-procedural aortic regurgitation, and rates of multiple device implantation, no difference between COP and CIT was found.ConclusionCOP is an effective and safe implantation technique to reduce the need for a permanent pacemaker implantation during TAVR with SE Evolut prosthesis.Graphical abstract

Incidence and management of atrioventricular conduction disorders in new-onset left bundle branch block after TAVI: A prospective multicenter study

New-onset left bundle branch block (LBBB) is one of the most frequent complications after transcatheter aortic valve implantation (TAVI) and is associated with delayed high degree atrioventricular (AV) block. The objectives of this study were to determine the incidence of AV block in such a population and to assess the performance and safety of a risk stratification algorithm on the basis of electrophysiology study (EPS) followed by implantation of a pacemaker or implantable loop recorder (ILR). This was a prospective open-label study with 12-month follow-up. From June 8, 2015, to November 8, 2018, 183 TAVI recipients (mean age 82.3 ± 5.9 years) were included at 10 centers. New-onset LBBB after TAVI persisting for >24 hours was assessed by electrophysiology study during initial hospitalization. High-risk patients (His-ventricle interval ≥70 ms) were implanted with a dual-chamber pacemaker recording AV conduction disturbance episodes. Patients at lower risk were implanted with an ILR with automatic remote monitoring. A high-grade AV conduction disorder was identified in 56 patients (30.6%) at 12 months. Four subjects were symptomatic, all in the ILR group. No complications were associated with the stratification procedure. Patients with His-ventricle interval ≥70 ms displayed more high-grade AV conduction disorders (53.2% [25 of 47] vs 22.8% [31 of 136]; P < .001). In a multivariate analysis, His-ventricle interval ≥70 ms was independently associated with the occurrence of a high-grade conduction disorder (subdistribution hazard ratio 2.4; 95% confidence interval 1.2-4.8; P = .010). New-onset LBBB after TAVI was associated with high rates of high-grade AV conduction disturbances. The stratification algorithm provided safe and valuable aid to management decisions and reliable guidance on pacemaker implantation.