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

Electrocardiogram-based prediction of conduction disturbances after transcatheter aortic valve replacement with convolutional neural network

Aims

Permanent pacemaker implantation and left bundle branch block are common complications after transcatheter aortic valve replacement (TAVR) and are associated with impaired prognosis. This study aimed to develop an artificial intelligence (AI) model for predicting conduction disturbances after TAVR using pre-procedural 12-lead electrocardiogram (ECG) images.

Methods and results

We collected pre-procedural 12-lead ECGs of patients who underwent TAVR at West China Hospital between March 2016 and March 2022. A hold-out testing set comprising 20% of the sample was randomly selected. We developed an AI model using a convolutional neural network, trained it using five-fold cross-validation and tested it on the hold-out testing cohort. We also developed and validated an enhanced model that included additional clinical features. After applying exclusion criteria, we included 1354 ECGs of 718 patients in the study. The AI model predicted conduction disturbances in the hold-out testing cohort with an area under the curve (AUC) of 0.764, accuracy of 0.743, F1 score of 0.752, sensitivity of 0.876, and specificity of 0.624, based solely on pre-procedural ECG images. The performance was better than the Emory score (AUC = 0.704), as well as the logistic (AUC = 0.574) and XGBoost (AUC = 0.520) models built with previously identified high-risk ECG patterns. After adding clinical features, there was an increase in the overall performance with an AUC of 0.779, accuracy of 0.774, F1 score of 0.776, sensitivity of 0.794, and specificity of 0.752.

Conclusion

Artificial intelligence-enhanced ECGs may offer better predictive value than traditionally defined high-risk ECG patterns.

Left bundle branch block-induced dilated cardiomyopathy: Definitions, pathophysiology, and therapy

Left bundle branch block (LBBB) is a frequent finding in patients with heart failure (HF), particularly in those with dilated cardiomyopathy (DCM). LBBB has been commonly described as a consequence of DCM development. However, a total recovery of left ventricular (LV) function after cardiac resynchronization therapy (CRT), observed in patients with LBBB and DCM, has led to increasing acknowledgement of LBBB-induced dilated cardiomyopathy (LBBB-iDCM) as a specific pathological entity. Its recognition has important clinical implications, as LBBB-iDCM patients may benefit from an early CRT strategy rather than medical HF therapy only. At present, there are no definitive diagnostic criteria enabling the universal identification of LBBB-iDCM, and no defined therapeutic approach in this subgroup of patients. This review compiles the main findings about LBBB-iDCM pathophysiology and the current proposed diagnostic criteria and therapeutic approach.

Mean compression ratio of a self-expandable valve is associated with the need for pacemaker implantation after transcatheter aortic valve replacement

BACKGROUND

The risk and timing of permanent pacemaker implantation (PPMI) after transcatheter aortic valve replacement (TAVR) is still hard to predict. We aimed to analyze the relationship between the compression ratio of a self-expandable valve (SEV) and the need for PPMI after TAVR.

METHODS

A total of 106 patients who were implanted with the VitaFlow transcatheter aortic valve system and for whom complete imaging information was available were included in this retrospective cohort study. Eight lines perpendicular to the long axis of the SEV were drawn (the top and bottom of the SEV and the intersection of each row of wires) for measurement purposes. The compression ratio was calculated as 1 - (in vivo meridian/in vitro meridian) and compared between patients undergoing and those not undergoing PPMI after adjusting for implantation depth. Multivariable logistic regression and Cox proportional hazards models were used to assess factors associated with the risk and timing of the need for PPMI.

RESULTS

Fifteen (14.2%) patients underwent PPMI after TAVR. Patients with a higher mean compression ratio (20%, odds ratio [OR] = 214.82; p < 0.001) and prior right bundle branch block (OR = 51.77; p = 0.015) had a higher risk of the need for PPMI after TAVR. These two factors were also associated with the timing of PPMI, according to the Cox proportional hazards model.

CONCLUSIONS

The compression ratio of the SEV was positively associated with the risk of PPMI after TAVR, and the association was most significant in the annular and supravalvular planes. The compression ratio may also affect the time to PPMI.

Transfemoral versus trans-subclavian access in transcatheter aortic valve implantation using self-expandable valve: A propensity-matched comparison

BACKGROUND

Transcatheter aortic valve implantation is unfeasible for 10-15% of patients using the conventional transfemoral approach. Other alternative approaches, such as the subclavian approach, have emerged, with no clear recommendation indicating the superiority of one technique over another.

AIM

To compare the 1-month mortality and postprocedural outcomes of patients undergoing transcatheter aortic valve implantation using a self-expandable valve via transfemoral and subclavian access.

METHODS

This was a retrospective single-centre study including 1496 patients who underwent transcatheter aortic valve implantation between January 2016 and December 2020 at Clermont-Ferrand University Hospital, France. Propensity score matching was used to compare transfemoral and subclavian access.

RESULTS

After building two propensity score-matched groups of 221 patients each with either access route (total n=442), baseline characteristics were similar. The procedure duration was significantly longer in the subclavian access group (53 [45-64] versus 60 [51-72] minutes; P<0.001), but with a lower amount of contrast agent (138 [118-165] versus 123 [105-150] mL; P<0.001), fluoroscopy time (11.2 [9-14] versus 9.9 [7-12] minutes; P<0.001) and radiation dose (397 [264-620] versus 321 [217-485] mGy; P<0.001). No significant difference was observed concerning 1-month mortality (odds ratio 1.62, 95% confidence interval 0.52-5.03; P=0.39) or periprocedural complications. Follow-up at 1 year confirmed no difference in longer-term mortality (hazard ratio 0.78, 95% confidence interval 0.52-5.03; P=0.43).

CONCLUSIONS

The subclavian approach provides similar results to the transfemoral approach in terms of mortality, efficacy and safety; it is a reasonable and effective alternative when the reference transfemoral approach is impossible or seems complex.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE STATEMENT

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

KEY POINTS

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

Novel predictors of permanent pacemaker implantation following transcatheter aortic valve replacement

BACKGROUND

Conduction and rhythm abnormalities requiring permanent pacemakers (PPM) are short-term complications following transcatheter aortic valve replacement (TAVR), and their clinical outcomes remain conflicting. Potential novel predictors of post-TAVR PPM, like QRS duration, QTc prolongation, and supraventricular arrhythmias, have been poorly studied.

AIM

To evaluate the effects of baseline nonspecific interventricular conduction delay and supraventricular arrhythmia on post-TAVR PPM requirement and determine the impact of PPM implantation on clinical outcomes.

METHODS

A retrospective cohort study that identified patients with TAVR between January 1, 2012 to December 31, 2019. The group was dichotomized into those with post-TAVR PPM and those without PPM. Both groups were followed for one year.

RESULTS

Out of the 357 patients that met inclusion criteria, the mean age was 80 years, 188 (52.7%) were male, and 57 (16%) had a PPM implantation. Baseline demographics, valve type, and cardiovascular risk factors were similar except for type II diabetes mellitus (DM), which was more prevalent in the PPM cohort (59.6% vs 40.7%; P = 0.009). The PPM cohort had a significantly higher rate of pre-procedure right bundle branch block, prolonged QRS > 120 ms, prolonged QTc > 470 ms, and supraventricular arrhythmias. There was a consistently significant increase in the odds ratio (OR) of PPM implantation for every 20 ms increase in the QRS duration above 100 ms: QRS 101-120 [OR: 2.44; confidence intervals (CI): 1.14-5.25; P = 0.022], QRS 121-140 (OR: 3.25; CI: 1.32-7.98; P = 0.010), QRS 141-160 (OR: 6.98; CI: 3.10-15.61; P < 0.001). After model adjustment for baseline risk factors, the OR remained significant for type II DM (aOR: 2.16; CI: 1.18-3.94; P = 0.012), QRS > 120 (aOR: 2.18; CI: 1.02-4.66; P = 0.045) and marginally significant for supraventricular arrhythmias (aOR: 1.82; CI: 0.97-3.42; P = 0.062). The PPM cohort had a higher adjusted OR of heart failure (HF) hospitalization (aOR: 2.2; CI: 1.1-4.3; P = 0.022) and nonfatal myocardial infarction (MI) (aOR: 3.9; CI: 1.1-14; P = 0.031) without any difference in mortality (aOR: 1.1; CI: 0.5-2.7; P = 0.796) at one year.

CONCLUSION

Pre-TAVR type II DM and QRS duration > 120, regardless of the presence of bundle branch blocks, are predictors of post-TAVR PPM. At 1-year post-TAVR, patients with PPM have higher odds of HF hospitalization and MI.

Left Bundle Branch Block: Characterization, Definitions, and Recent Insights into Conduction System Physiology

Left bundle branch block (LBBB) is not just a simple electrocardiogram alteration. The intricacies of this general terminology go beyond simple conduction block. This review puts together current knowledge on the historical concept of LBBB, clinical significance, and recent insights into the pathophysiology of human LBBB. LBBB is an entity that affects patient diagnosis (primary conduction disease, secondary to underlying pathology or iatrogenic), treatment (cardiac resynchronization therapy or conduction system pacing for heart failure), and prognosis. Recruiting the left bundle branch with conduction system pacing depends on the complex interaction between anatomy, site of pathophysiology, and delivery tools.

A prediction model for permanent pacemaker implantation after transcatheter aortic valve replacement

BACKGROUND

This study aims to develop a post-procedural risk prediction model for permanent pacemaker implantation (PPMI) in patients treated with transcatheter aortic valve replacement (TAVR).

METHODS

336 patients undergoing TAVR at a single institution were included for model derivation. For primary analysis, multivariate logistic regression model was used to evaluate predictors and a risk score system was devised based on the prediction model. For secondary analysis, a Cox proportion hazard model was performed to assess characteristics associated with the time from TAVR to PPMI. The model was validated internally via bootstrap and externally using an independent cohort.

RESULTS

48 (14.3%) patients in the derivation set had PPMI after TAVR. Prior right bundle branch block (RBBB, OR: 10.46; p < 0.001), pre-procedural aortic valve area (AVA, OR: 1.41; p = 0.004) and post- to pre-procedural AVA ratio (OR: 1.72; p = 0.043) were identified as independent predictors for PPMI. AUC was 0.7 and 0.71 in the derivation and external validation set. Prior RBBB (HR: 5.07; p < 0.001), pre-procedural AVA (HR: 1.33; p = 0.001), post-procedural AVA to prosthetic nominal area ratio (HR: 0.02; p = 0.039) and post- to pre-procedural troponin-T difference (HR: 1.72; p = 0.017) are independently associated with time to PPMI.

CONCLUSIONS

The post-procedural prediction model achieved high discriminative power and accuracy for PPMI. The risk score system was constructed and validated, providing an accessible tool in clinical setting regarding the Chinese population.

Cusp overlap versus standard three-cusp technique for self-expanding Evolut transcatheter aortic valves

BACKGROUND

Reducing rates of permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI) is important for achieving the best procedural outcomes. The cusp overlap technique (COT) implements procedural steps including an overlap angulation of the right and left coronary cusp to mitigate this complication.

AIMS

We investigated the incidence of PPI and complication rates following the COT compared to the standard three-cusp implantation technique (3CT) in an all-comers cohort.

METHODS

A total of 2,209 patients underwent TAVI with the self-expanding Evolut platform from January 2016 to April 2022 at five sites. Baseline, procedural and in-hospital outcome characteristics were compared for both techniques before and after one-to-one propensity score matching.

RESULTS

A total of 1,151 patients were implanted using the 3CT and 1,058 using the COT. At discharge, the rates of PPI (17.0 vs 12.3%; p=0.002) and moderate/severe paravalvular regurgitation (4.6% vs 2.4%; p=0.006) were significantly reduced with the COT compared with 3CT within the unmatched cohort. Overall procedural success and complication rates were similar; major bleeding was less common in the COT group (7.0% vs 4.6%; p=0.020). These results remained consistent after propensity score matching. In multivariable logistic regression analysis, right bundle branch block (odds ratio [OR] 7.19, 95% confidence interval [CI]: 5.18-10.0; p<0.001) and diabetes mellitus (OR 1.38, 95% CI: 1.05-1.80; p=0.021) emerged as predictors of PPI, whereas the COT (OR 0.63, 95% CI: 0.49-0.82; p<0.001) was protective.

CONCLUSIONS

The introduction of the COT was associated with a significant and relevant reduction of PPI and paravalvular regurgitation rates without an increase in complication rates.

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

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

In-hospital outcomes of TAVR patients with a bundle branch block: Insights from the National Inpatient Sample 2011-2018

INTRODUCTION

Data on the outcomes following transcatheter aortic valve replacement (TAVR) in patients with a bundle branch block (BBB) remains limited.

METHODS

We studied the outcomes of TAVR patients with a BBB from the National Inpatient Sample (NIS) database between 2011 and 2018 using ICD-9-CM and ICD-10-CM codes.

RESULTS

Between 2011 and 2018, 194,237 patients underwent TAVR, where 1.7% (n = 3,232) had a right BBB (RBBB) and 13.7% (n = 26,689) had a left BBB (LBBB). Patients with a RBBB and LBBB had a higher rate of new permanent pacemaker (PPM) implantation (31.5% - RBBB, 15.7% LBBB vs. 10.2% - no BBB). RBBB was associated with a significantly longer median length of stay (5 days) and total hospitalization cost ($53,669) compared with LBBB (3 days and $47,552) and no BBB (3 days and $47,171). Trend analysis revealed lower rates of PPM implantation and reduced lengths of stay and costs across all comparison groups.

CONCLUSION

In conclusion, patients undergoing TAVR with a BBB are associated with higher new rates of PPM implantation. RBBB is the strongest independent predictor for new PPM implantation following TAVR. Rates of new PPM implantation in TAVR patients with and without a BBB have improved over time including reductions in length of stay and hospital costs. Further study is needed to reduce the risks of PPM implantation in TAVR patients.

Prognostic Outcome of New-Onset Left Bundle Branch Block After Transcatheter Aortic Valve Replacement in Patients With Aortic Stenosis: A Systematic Review and Meta-Analysis

Background

Left bundle branch block (LBBB) is a common complication of the transcatheter aortic valve replacement (TAVR), and its impact on prognosis is controversial.

Methods

A comprehensive electronic search was conducted in databases (PubMed, Embase, Cochrane Library, and The Web of Science), from the date of database establishment till March 2021, to screen for studies on new-onset LBBB after TAVR. We next performed a meta-analysis to evaluate the effect of new-onset LBBB after TAVR on patient prognosis, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

Results

A total of 17 studies, including 9205 patients, were eligible for our analysis. Patients with new-onset LBBB had elevated all-cause mortality risk verses patients without new-onset LBBB, during all follow ups. The relevant data are as follows: 30-day (RR:1.71; 95%CI:1.27–2.29; P &lt; 0.001), 1-year (RR:1.31; 95%CI:1.12–1.52; P &lt; 0.001), and 2-year (RR:1.31; 95%CI:1.09–1.56; P = 0.003) follow ups. Likewise, new-onset LBBB patients also experienced increased cardiovascular mortality, compared to non-new-onset LBBB patients, but only in the 1-year follow up (RR:1.49; 95%CI:1.23–1.82; P &lt; 0.001). Hospitalization for heart failure was dramatically elevated in patients with new-onset LBBB verses non-new-onset LBBB, in all follow ups. The relevant data are as follows: 30-day (RR:1.56; 95%CI:1.13–2.12; P = 0.007), 1-year (RR:1.35; 95%CI:1.08–1.68; P = 0.007), and 2-year (RR:1.49; 95%CI:1.21–1.84; P &lt; 0.001). Similarly, new-onset LBBB patients had higher PPI risk than non-new-onset LBBB patients, in all follow ups. The relevant data are as follows: 30-day (RR:3.05; 95%CI:1.49–6.22; P = 0.002), 1-year (RR:2.15; 95%CI:1.52–3.03; P &lt; 0.001), and 2-year (RR:2.52; 95%CI:1.68–3.78; P &lt; 0.001).

Conclusion

Patients with new-onset LBBB have worse prognosis after TAVR than those without new-onset LBBB. Recognition of the adverse effects of post-TAVR new-onset LBBB can lead to the development of new strategies that enhance clinical outcomes.

Systematic Trial Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=197224, identifier: 19722.

Advantages and disadvantages of drug challenge during electrophysiological study in patients with new left bundle branch block after transaortic valve implantation

Aims

Electrophysiological study (EPS) is recommended in case of new-onset persistent left bundle branch block (NOP-LBBB) after transaortic valve implantation (TAVI) to identify patients at high risk of delayed atrioventricular block (D-AVB). We evaluated the added value of drug challenge, after normal baseline EPS, to predict D-AVB in such patients.

Methods

We conducted a comparative single-centre study of two successive periods, during which we used baseline EPS alone (first period) or drug challenge in case of normal baseline EPS (second period), for patients with NOP-LBBB after TAVI. The primary endpoint was a composite of pacemaker use, documented D-AVB, cardiac syncope, sudden death, or delayed pacemaker implantation.

Results

Among 736 patients with TAVI implantation between January 2016 and September 2019, 64 with NOP-LBBB were included. During the first period, 4/22 (18.2%) presented with a positive baseline EPS. After a mean (standard deviation [SD]) of 15.6 (8.3) months, 7/22 (31.8%) reached the primary endpoint. During the second period, 19/42 (45.2%) presented with a positive EPS. After a mean (SD) of 12.8 (3.5) months, 8/42 (19.0%) reached the primary endpoint. There was a tendency to increased sensitivity (42.9–87.5%; P = 0.12) and negative predictive value (77.8–95.7%; P = 0.15) of the EPS, respectively during the first to the second period. However, the specificity decreased (93.3–64.7%; P = 0.04).

Conclusion

Diagnostic yield improved with drug challenge in case of normal baseline EPS. However, the decrease in specificity led to a high rate of unnecessary pacemaker implantation.

Left Bundle Branch Block: Characterization, Definitions, and Recent Insights into Conduction System Physiology

Left bundle branch block (LBBB) is not just a simple electrocardiogram alteration. The intricacies of this general terminology go beyond simple conduction block. This review puts together current knowledge on the historical concept of LBBB, clinical significance, and recent insights into the pathophysiology of human LBBB. LBBB is an entity that affects patient diagnosis (primary conduction disease, secondary to underlying pathology or iatrogenic), treatment (cardiac resynchronization therapy or conduction system pacing for heart failure), and prognosis. Recruiting the left bundle branch with conduction system pacing depends on the complex interaction between anatomy, site of pathophysiology, and delivery tools.

Conduction Disturbances and Pacing in Transcatheter Aortic Valve Replacement

Conduction disturbances (CDs) after transcatheter artic replacement remain a clinical concern and relatively common complication. A recent meta-analysis showed both new-onset persistent left bundle branch block and new permanent pacemaker implantation were related to all-cause death with risk ratio 1.32 (95% confidence interval [CI] 1.17 to 1.49; P<.001) and 1.17 (95% CI 1.11-1.25; P<.001) at 1 year, respectively. Preprocedural computed tomography imaging can highlight potential risk factors for CDs, such as membranous septum length, device landing zone calcium, and the annulus size/degree of device oversizing.

Increased Rate of New-onset Left Bundle Branch Block in Patients With Bicuspid Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation (From a National Registry)

There is a growing interest in transcutaneous aortic valve implantation (TAVI) therapy among patients with bicuspid severe aortic stenosis (BAV). Conduction disturbances remain a frequent complication of TAVI, and new-onset permanent LBBB (NOP-LBBB) post-TAVI may be a marker of worse outcomes. We aimed to evaluate the rate of NOP-LBBB following TAVI among patients with BAV as compared to tricuspid severe aortic stenosis (TAV). Patients enrolled in the multicenter (5 centers) Bicuspid AS TAVI Registry were reviewed and compared with patients with TAV. Patients with previous aortic valve replacement, other valve morphologies and those with preprocedural LBBB or pacemaker were excluded. NOP-LBBB was defined as LBBB first detected and persisting 30-days following TAVI. A total of 387 patients (66 with BAV, 321 with TAV), age 80.3 ± 7.3, 47% females were analyzed. The device success rates were 95% in both groups without any conversions to surgery. The rate of NOP-LBBB was significantly higher among patients with BAV versus TAV (29.2% vs 16.9%, p = 0.02). However, the rate of post procedural pacemaker implantation was similar (14.8% vs 12.5%; respectively, p = 0.62). In BAV and TAV groups, 1-year mortality (6.1% vs 7.2%; respectively, p = 0.75) and stroke rates (6.1% vs 3.5%; respectively, p = 0.30) were not significantly different. Multivariate analysis identified BAV as an independent predictor of NOP-LBBB (AdjOR = 2.7, 95%CI 1.3 to 5.4). Furthermore, BAV subtypes with raphe (type 1) were identified as independent predictors of NOP-LBBB (AdjOR = 3.2, 95%CI: 1.5 to 6.7). In conclusion, patients with BAV undergoing TAVI have greater risk for developing NOP-LBBB compared with patients with TAV and the presence of raphe was associated with increased risk of NOP-LBBB. The prognostic significance for this finding warrants further evaluation in future studies.

Incidence, Predictors, and Implications of Permanent Pacemaker Requirement After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) is a safe and feasible alternative to surgery in patients with symptomatic severe aortic stenosis regardless of the surgical risk. Conduction abnormalities requiring permanent pacemaker (PPM) implantation remain a common finding after TAVR due to the close proximity of the atrioventricular conduction system to the aortic root. High-grade atrioventricular block and new onset left bundle branch block (LBBB) are the most commonly reported conduction abnormalities after TAVR. The overall rate of PPM implantation after TAVR varies and is related to pre-procedural and intraprocedural factors. The available literature regarding the impact of conduction abnormalities and PPM requirement on morbidity and mortality is still conflicting. Pre-procedural conduction abnormalities such as right bundle branch block and LBBB have been linked with increased PPM implantation and mortality after TAVR. When screening patients for TAVR, heart teams should be aware of various anatomical and pathophysiological conditions that make patients more susceptible to increased risk of conduction abnormalities and PPM requirement after the procedure. This is particularly important as TAVR has been recently approved for patients with low surgical risk. The purpose of this review is to discuss the incidence, predictors, impact, and management of the various conduction abnormalities requiring PPM implantation in patients undergoing TAVR.

Impact of Bundle Branch Block on Permanent Pacemaker Implantation after Transcatheter Aortic Valve Implantation: A Meta-Analysis

Data regarding the impact of infra-Hisian conduction disturbances leading to permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI) remain limited. The aim of this study was to determine the impact of right and/or left bundle branch block (RBBB/LBBB) on post-TAVI PPI. We performed a systematic literature review to identify studies reporting on RBBB and/or LBBB status and post-TAVI PPI. Study design, patient characteristics, and the presence of branch block were analyzed. Odds ratios (ORs) with 95% CI were extracted. The final analysis included 36 studies, reporting about 55,851 patients. Data on LBBB were extracted from 33 studies. Among 51,026 patients included, 5503 showed pre-implant LBBB (11.9% (10.4%–13.8%)). The influence of LBBB on post-TAVI PPI was not significant OR 1.1474 (0.9025; 1.4588), p = 0.2618. Data on RBBB were extracted from 28 studies. Among 46,663 patients included, 31,603 showed pre-implant RBBB (9.2% (7.3%–11.6%)). The influence of RBBB on post-TAVI PPI was significant OR 4.8581 (4.1571; 5.6775), p < 0.0001. From this meta-analysis, the presence of RBBB increased the risk for post-TAVI PPI, independent of age or LVEF, while this finding was not confirmed for patients experimenting with LBBB. This result emphasizes the need for pre-operative evaluation strategies in patient selection for TAVI.

Recovery of conduction disorders after sutureless aortic valve replacement

OBJECTIVES

Conduction disorders and the need for permanent pacemaker (PPM) implantation after surgical aortic valve replacement are well-recognized complications. However, in the case of sutureless valve prostheses, it remains unknown whether pacemaker (PM) dependency and conduction disturbances resolve over time. Our aim was to evaluate whether conduction disorders after Perceval sutureless valve implantation recover during follow-up.

METHODS

Patients undergoing isolated surgical aortic valve replacement or concomitant aortic valve replacement with coronary artery bypass surgery using the Perceval sutureless valve, between January 2010 and July 2018, were included. Postoperative electrocardiogram findings were analysed to determine the incidence of new-onset left bundle branch blocks (LBBBs) and the requirement for PPM implantation. During a postoperative period of 6-18 months, electrocardiogram findings during PM checks were analysed to determine PM dependency and LBBB persistence.

RESULTS

Out of 184 patients who received a Perceval prosthesis during the study period, 39 (21.2%) patients developed new-onset LBBB and 10 patients (5.4%) received a PPM postoperatively. The occurrence of conduction disorders was not associated with valve size. Follow-up was completed in 176 (95.7%) patients. In patients with a new-onset LBBB, 35.9% recovered during follow-up (P = 0.001). Seven out of 10 (70%) patients remained PM dependent.

CONCLUSIONS

After Perceval aortic valve implantation, new-onset LBBB recovers in more than one-third of patients during follow-up. In patients who needed a postoperative PPM, the majority remained PM dependent.

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.

Clinical Impact of Preexisting Right Bundle Branch Block after Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-Analysis

Introduction

Transcatheter aortic valve replacement (TAVR) is now the treatment of choice for patients with severe aortic stenosis regardless of their surgical risk. Right bundle branch block (RBBB) can be a predictor for development of significant atrioventricular (AV) block after TAVR, requiring permanent pacemaker implantation (PPI). However, data related to the risk of PPI requirement with preexisting RBBB is scarce. Hence, this systematic review and meta-analysis aims to assess clinical outcomes of patients undergoing TAVR with RBBB on preexisting electrocardiogram.

Methods

We performed a systematic literature review to identify randomized and nonrandomized clinical studies that reported any clinical impact of patients undergoing TAVR with preexisting RBBB. A total of eight databases including PubMed (Medline), Embase, Cochrane Library, ACP Journal Club, Scopus, DARE, and Ovid containing articles from January 2000 to May 2020 were analyzed.

Results

We identified and screened 224 potential eligible publications through the databases and found 14 relevant clinical trials for a total of 15,319 participants. There was an increased 30-day pacemaker implantation rate of 38.1% in the RBBB group compared to 11.4% in the no RBBB group with a risk ratio of 3.56 (RR 3.56 (95% CI 3.21–3.93, p < 0.01)). There was an increased 30-day all-cause mortality in the RBBB group of 9.5% compared with 6.3% in the no RBBB group with an odds ratio of 1.60 (OR 1.60 (95% CI 1.14–2.25, p < 0.01)).

Conclusion

This study indicates that patients with preexisting RBBB have higher incidence of PPI and all-cause mortality after TAVR compared with patients without RBBB. Further trials are needed to compare the clinical outcomes based on TAVR valve types and assess the benefit of PPI in patients with new-onset RBBB after TAVR.

Left Bundle Branch Block: Current and Future Perspectives

Left bundle branch block may be due to conduction system degeneration or a reflection of myocardial pathology. Left bundle branch block may also develop following aortic valve disease or cardiac procedures. Patients with heart failure with reduced ejection fraction and left bundle branch block may respond positively to cardiac resynchronization therapy. Lead placement via the coronary sinus is the mainstay approach of cardiac resynchronization therapy. However, other options, including physiological pacing, are being explored. In this review, we summarize the salient pathophysiologic and clinical aspects of left bundle branch block, as well as current and future strategies for management.

Mortality after transcatheter versus surgical aortic valve replacement: an updated meta-analysis of randomised trials

Background

To determine whether transcatheter aortic valve implantation (TAVI) improves early (30-day) and midterm (1-year) mortality compared with surgical aortic valve replacement (SAVR), we performed an updated meta-analysis of all the currently available randomised controlled trials (RCTs).

Methods

To identify all RCTs providing both 30-day and 1‑year mortality after TAVI versus SAVR, PubMed and ClinicalTrials.gov were searched up to and including July 2019. A risk difference (RD) and its 95% confidence interval were generated using data of prespecified outcomes in both the TAVI and SAVR groups. Study-specific estimates were pooled using inverse variance-weighted averages of RDs in the random-effects model.

Results

We identified seven eligible high-quality RCTs including a total of 7631 as-treated patients. Pooled analyses demonstrated significantly lower 30-day (RD −0.60%; p = 0.046) and 1‑year all-cause mortality (RD −1.12%; p = 0.03) after TAVI than after SAVR. No funnel plot asymmetry was detected for 30-day and 1‑year mortality. Meta-regression analyses indicated that RDs of 30-day and 1‑year mortality between TAVI and SAVR were not modulated by mean Society of Thoracic Surgeons Predicted Risk of Mortality score. Bleeding complications at 30 days and 1 year and stage 2/3 acute kidney injury at 30 days were significantly less frequent after TAVI than after SAVR, whereas major vascular complications and new permanent pacemaker implantation at 30 days and 1 year were significantly more frequent after TAVI than after SAVR.

Conclusion

The best evidence from the present meta-analysis of all the currently available RCTs suggests that TAVI may reduce 30-day and 1‑year all-cause mortality compared with SAVR.

Electronic supplementary material

The online version of this article (10.1007/s12471-020-01378-1) contains supplementary material, which is available to authorized users.

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

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

Progression of incomplete toward complete left bundle branch block: A clinical and electrocardiographic analysis

Background

Complete left bundle branch block (cLBBB) is associated with increased cardiovascular mortality and heart failure. On the contrary, the clinical relevance of incomplete left bundle branch block (iLBBB) is less known. This study investigated the profile and outcome of iLBBB patients and assessed the risk of progression to cLBBB.

Methods

Patients diagnosed with iLBBB between July 2013 and April 2018 were retrospectively included. Subsequently, echo‐ and electrocardiographic examinations at time of iLBBB diagnosis and during follow‐up, as well as progression to non‐strict cLBBB and strict cLBBB, were evaluated.

Results

The study enrolled 321 patients (33% female, age 74 ± 11 years). During the follow‐up of 21 (8;34) months, 33% of iLBBB patients evolved to non‐strict cLBBB and 27% to strict cLBBB. iLBBB patients who evolved to non‐strict or strict cLBBB were older, had more frequently reduced left ventricular ejection fraction, and had more often QRS notching/slurring in the lateral leads and inferior leads, compared to patients without progression to cLBBB. In multivariate analysis, only QRS notching/slurring in the lateral leads was independently associated with progression to non‐strict cLBBB (odds ratio 4.64, p < .001) and strict cLBBB (odds ratio 9.6, p < .001). iLBBB patients with QRS notching/slurring had a progression rate to non‐strict cLBBB of 52% and 49% to strict cLBBB.

Conclusion

Among patients with iLBBB, up to one third of the patients progress to cLBBB within a period of 2 years. The presence of QRS notching/slurring in the lateral leads during iLBBB was the strongest predictor for progression toward cLBBB.

A meta-analysis of ≥5-year mortality after transcatheter versus surgical aortic valve replacement

INTRODUCTION

It remains unclear whether long-term survival is superior following transcatheter aortic valve implantation (TAVI) than following surgical aortic valve replacement (SAVR). We performed a meta-analysis of mortality with ≥5-year follow-up in randomized controlled trials (RCTs) and propensity-score matched (PSM) studies of TAVI versus SAVR.

EVIDENCE ACQUISITION

MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched through March 2019. Eligible studies were RCTs or PSM studies of TAVI versus SAVR enrolling patients with severe aortic stenosis and reporting all-cause mortality with ≥5-year follow-up as an outcome. A hazard ratio of mortality for TAVI versus SAVR was extracted from each individual study.

EVIDENCE SYNTHESIS

Our search identified 3 RCTs and 7 PSM studies enrolling 5498 patients. A pooled analysis of all 10 studies demonstrated a statistically significant 38% increase in mortality with TAVI relative to SAVR. A subgroup meta-analysis showed no statistically significant difference between TAVI and AVR in RCTs and a statistically significant 68% increase with TAVI relative to SAVR in PSM studies.

CONCLUSIONS

On the basis of a meta-analysis of 7 PSM studies, TAVI is associated with greater all-cause mortality with ≥5-year follow-up than SAVR. However, another meta-analysis of 3 RCTs suggests no difference in mortality between TAVI and SAVR.

Incidence of arrhythmias and impact of permanent pacemaker implantation in hospitalizations with transcatheter aortic valve replacement

BACKGROUND

This study sought to analyze in-hospital outcomes associated with preexisting and newly implanted permanent pacemaker (PPM) in patients who underwent transcatheter aortic valve replacement (TAVR). PPM implantation following the development of conduction abnormalities is a common adverse event following TAVR. Furthermore, PPM implantation rates are higher in TAVR hospitalizations compared with the surgical alternative, thus we have analyzed the predictors of pacing post-TAVR.

HYPOTHESIS

We hypothesize that incidence of arrhythmias are high post-TAVR and have worse adverse outcomes after receiving PPM.

METHODS

The study population was identified from the National Inpatient Sample database between 2012 and 2014. TAVR population was identified using ICD-9-CM procedure codes 35.05 and 35.06. Hospitalizations were divided into 3 group: (1) with preexisting PPM, (2) with newly implanted PPM, and (3) without any PPM.

RESULTS

Overall, 0.8% of hospitalizations presented with preexisting PPM and 23.7% of hospitalizations received new PPM. The overall incidence of atrial fibrillation was 44.5%, left bundle branch block 8.9%, complete atrioventricular block 9.5%, and right bundle branch block 2.7%. In-hospital mortality was higher in hospitalizations receiving PPM compared with those without (4.9% vs 4.0%; P = 0.05). Length of stay and cost were higher in the group receiving new PPM. Female sex, atrial fibrillation, left bundle branch block, and second-degree and complete atrioventricular block were significant predictors for receiving PPM after TAVR.

CONCLUSIONS

A risk stratification for hospitalizations with conduction disorders is necessary to avoid longer hospital stays, added costs, and mortality. Further research is warranted to investigate additional predictors for PPM after TAVR.

Atrial fibrillation in patients undergoing transcatheter aortic valve implantation: epidemiology, timing, predictors, and outcome

Atrial fibrillation (AF) is a common arrhythmia in patients with aortic stenosis. When these patients are treated medically or by surgical aortic valve replacement, AF is associated with increased risk of adverse events including death. Growing evidence suggests a significant impact of AF on outcomes also in patients with aortic valve stenosis undergoing transcatheter aortic valve implantation (TAVI). Conversely, limited evidence is available regarding the optimal management of this condition. This review aims to summarize prevalence, pathophysiology, prognosis, and treatment of AF in patients undergoing 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.

Current rare indications and future directions for implantable loop recorders

The scope of application for implantable loop recorders has shifted away from the evaluation of unclear palpitations and syncope episodes to more complex conditions. This article focuses on rare indications of growing importance such as rhythm monitoring after ablation of atrial fibrillation or after cryptogenic stroke. Furthermore, forthcoming applications in various clinical settings are described, e. g., arrhythmia detection after myocardial infarction, after catheter-based valve interventions, in heart failure, and in cardiomyopathies. Enhancement of the capabilities of implantable loop recorders could broaden their fields of use.

Effect of New-Onset Left Bundle Branch Block After Transcatheter Aortic Valve Implantation (CoreValve) on Mortality, Frequency of Re-Hospitalization, and Need for Pacemaker

New-onset conduction disturbances are common after transcatheter aortic valve implantation (TAVI). The most common complication is left bundle branch block (LBBB). The clinical impact of new-onset LBBB after TAVI remains controversial. The aim of this study was to analyze the clinical impact of new-onset LBBB in terms of mortality and morbidity (need for pacemakers and admissions for heart failure) at long-term follow-up. From April 2008 to December 2014, 220 patients who had severe aortic stenosis were treated with the implantation of a CoreValve prosthesis. Sixty-seven of these patients were excluded from the analysis, including 22 patients with pre-existing LBBB and 45 with a permanent pacemaker, implanted previously or within 72 hours of implantation. The remaining 153 patients were divided into 2 groups: group 1 (n = 80), those with persistent new-onset LBBB, and group 2 (n = 73), those without conduction disturbances after treatment. Both groups were followed up at 1 month, 6 months, 12 months, and yearly thereafter. Persistent new-onset LBBB occurred in 80 patients (36%) immediately after TAVI; 73 patients (33%) did not develop conduction disturbances. The mean follow-up time of both groups was 32 ± 22 months (range 3 to 82 months), and there were no differences in time between the groups. There were no differences in mortality between the groups (39% vs 48%, p = 0.58). No differences were observed between the groups in re-hospitalizations for heart failure (11% vs 16%, p = 0.55). Group 1 did not require pacemaker implantation more often at follow-up (10% vs 13%, p = 0.38) than group 2. In conclusion, new-onset LBBB was not associated with a higher incidence of late need for a permanent pacemaker after CoreValve implantation. In addition, it was not associated with a higher risk of late mortality or re-hospitalization.