Clinical characteristics, incidence, and outcomes of transcatheter aortic valve implantation stratified by new-onset left bundle branch block: A single-center pilot study

Fajer Alabdulrazzaq; Mohammed Al Jarallah; Rajesh Rajan; Raja Dashti; Nader Alasousi; Vladimir Kotevski; Ahmed Said Taha Mousa; Gary Tse; Kobalava D Zhanna; Parul Setiya; Ahmad Al-Saber; Peter A Brady; Joud Al Balool

doi:10.4103/ACCJ.ACCJ_20_21

ORIGINAL ARTICLE

Year : 2022 | Volume : 4 | Issue : 1 | Page : 9-14

Clinical characteristics, incidence, and outcomes of transcatheter aortic valve implantation stratified by new-onset left bundle branch block: A single-center pilot study

Fajer Alabdulrazzaq¹, Mohammed Al Jarallah², Rajesh Rajan³, Raja Dashti², Nader Alasousi², Vladimir Kotevski², Ahmed Said Taha Mousa², Gary Tse⁴, Kobalava D Zhanna⁵, Parul Setiya⁶, Ahmad Al-Saber⁷, Peter A Brady⁸, Joud Al Balool⁹
¹ Faculty of Medicine, Royal College of Surgeons Ireland, Dublin, Ireland
² Department of Cardiology, Sabah Al Ahmed Cardiac Centre, Al Amiri Hospital, Kuwait City, Kuwait
³ Department of Cardiology, Sabah Al Ahmed Cardiac Centre, Al Amiri Hospital, Kuwait City, Kuwait; Department of Internal Medicine with the Subspecialty of Cardiology and Functional Diagnostics Named after V.S. Moiseev, Institute of Medicine, Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation
⁴ Cardiovascular Analytics Group, Hong Kong, China, Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin 300211, China
⁵ Department of Internal Medicine with the Subspecialty of Cardiology and Functional Diagnostics Named after V.S. Moiseev, Institute of Medicine, Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation
⁶ Department of Agrometeorology, College of Agriculture, G.B.Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India
⁷ Department of Mathematics and Statistics, University of Strathclyde, Glasgow, G1 1XH, UK
⁸ Department of Cardiology, Illinois Masonic Medical Center, Chicago, IL, USA
⁹ Faculty of Medicine, Kuwait University, Jabria, Kuwait

Date of Submission	05-Dec-2021
Date of Decision	09-Feb-2022
Date of Acceptance	12-Apr-2022
Date of Web Publication	30-Jun-2022

Correspondence Address:
Dr. Rajesh Rajan
Department of Cardiology, Sabah Al Ahmed Cardiac Centre, Al Amiri Hospital, Kuwait City 15003

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ACCJ.ACCJ_20_21

Abstract

Background: Clinical outcomes after transcatheter aortic valve implantation (TAVI) patients have not been reported in the Gulf region. Objectives: To define the baseline electrocardiographic (ECG), echocardiographic, and computed tomographic findings of patients undergoing TAVI and analyze the predictors of developing new-onset persistent left bundle branch block (LBBB). Methods: Patients with severe aortic stenosis who underwent TAVI between 2013 and 2021 at the Sabah Al-Ahmed Cardiac Centre in Al-Amiri Hospital in the state of Kuwait were included in this study. Baseline characteristics, electrocardiography (ECG), echocardiography, and preprocedural computed tomography data were extracted. The primary outcome was new-onset LBBB. Results: A total of 61 patients were included (65.6% females; mean age: 73.5 ± 9 years; baseline ejection fraction: 55.5% ± 9.7%). Of these, 18 developed new-onset LBBB. Those who developed LBBB tended to have lower ejection fraction (52.5 ± 9.6 vs. 56.8% ± 9.5%; P = 0.116). Those who developed LBBB were more likely to develop 1^st degree atrioventricular block post-TAVI (P = 0.001). Conclusion: The incidence of new-onset LBBB post-TAVI was 29.5%. The new-onset LBBB group was more likely to develop conduction abnormalities requiring permanent pacemaker implantation.

Keywords: Atrioventricular block, left bundle branch block, transcatheter aortic valve implantation

How to cite this article:
Alabdulrazzaq F, Al Jarallah M, Rajan R, Dashti R, Alasousi N, Kotevski V, Taha Mousa AS, Tse G, Zhanna KD, Setiya P, Al-Saber A, Brady PA, Al Balool J. Clinical characteristics, incidence, and outcomes of transcatheter aortic valve implantation stratified by new-onset left bundle branch block: A single-center pilot study. Ann Clin Cardiol 2022;4:9-14

How to cite this URL:
Alabdulrazzaq F, Al Jarallah M, Rajan R, Dashti R, Alasousi N, Kotevski V, Taha Mousa AS, Tse G, Zhanna KD, Setiya P, Al-Saber A, Brady PA, Al Balool J. Clinical characteristics, incidence, and outcomes of transcatheter aortic valve implantation stratified by new-onset left bundle branch block: A single-center pilot study. Ann Clin Cardiol [serial online] 2022 [cited 2023 Jun 4];4:9-14. Available from: http://www.onlineacc.org/text.asp?2022/4/1/9/349337

Introduction

Transcatheter aortic valve implantation (TAVI) is a new procedure used as an alternative therapy for the treatment of severe symptomatic aortic stenosis for patients with intermediate and high surgical risk or inoperable patients.^{[1],[2],[3],[4]} Although TAVI is a safe procedure, complications can develop post- and perioperatively, mainly with the development of conduction abnormalities, including new-onset persistent left bundle branch block (LBBB), with an incidence between 30% and 50%.^[1],[2] This complication is explained by the proximity of the aortic valve to the conduction system, namely, the left bundle branch. During the procedure, mechanical stress is exerted from the prosthesis skirt on the interventricular septum, leading to conduction dysfunction.^[1],[5] In terms of outcomes, patients who develop new-onset LBBB are at higher risk of requiring permanent pacemaker implantation (PPI) because of the progression to complete atrioventricular (AV) heart block.^[1],[5],[6] In addition, the left ventricle ejection fraction of the new-onset LBBB group failed to increase due to suboptimal left ventricular remodeling, ultimately leading to heart failure.^{[6],[7],[8],[9],[10]} As a result, patients who develop new-onset LBBB post-TAVI have a higher risk of mortality than the TAVI group without new-onset LBBB.^[1],[2],[8]

Therefore, the aim of our study was to analyze the incidence and predictors of new-onset persistent LBBB development after TAVI.

Methods

Study population and design

This was a retrospective study. The study included 61 severe symptomatic aortic stenosis patients who underwent TAVI in Sabah Al-Ahmed Cardiac Centre in Al-Amiri Hospital in the State of Kuwait from 2018 to 2021. Retrospectively collected data were used to define this study population using electrocardiography, echocardiography, and preprocedural computed tomography (CT) data.^[11] We stratified patients into two subgroups: a group with new-onset LBBB and a group without new-onset LBBB post-TAVI. The type of TAVI prosthesis used is the balloon expandable Edwards SAPIEN valve (ESV) through the transfemoral route. The bioprosthesis sizes used in implantation were 24 mm and 25 mm valves. The study protocol was approved by the Ethical Committee at the Ministry of Health.

Electrocardiography, echocardiography, and computed tomography

Electrocardiography records from all patients were retrospectively collected and analyzed, including baseline and post-TAVI ECG. Baseline ECG was assessed for sinus rhythm and preexisting conduction abnormalities. Post-TAVI ECG was assessed for new conduction abnormalities and PPI. Transthoracic echocardiography data were collected at baseline and evaluated for ejection fraction, left ventricle hypertrophy, other valve disorders, left ventricular dysfunction, and aortic dimensions. Preprocedure CT images were collected and analyzed for aortic valve dimensions.

Statistical analysis

Continuous variables were expressed as the mean and standard deviation and were further analyzed using linear model ANOVA. Categorical variables were displayed as frequencies and percentages, and significant differences were analyzed using Pearson's Chi-square test. Statistical significance was measured as a P < 0.05.

Results

Baseline characteristics

The majority of our study population was elderly females (65.6%), with a mean age of 73.5 ± 9 years. All patients were implanted with an ESV with a mean size of 24.8 ± 2 mm, and patients who developed new-onset LBBB post-TAVI had a slightly larger implant with a mean size of 25.3 ± 1.9 mm than the group without new-onset LBBB (P = 0.157).

Other patient characteristics were explored, including body mass index and cardiovascular history of hypertension, smoking, myocardial infarction, and stroke, all of which showed no association with LBBB development post-TAVI. [Table 1] shows the baseline characteristics of the 61 patients included in the study. Medication records show that statin usage was common, with a prevalence of 34/61 (54.1%), mostly used by the new-onset LBBB Group 15/18 (83.3%, P = 0.005), suggesting that this group was more likely to have dyslipidemia. Other prevalent medications included aspirin 32/61 (52.5%) and bisoprolol 36/61 (59%). [Table 2] shows a detailed list of medications taken by our study population.

Table 1: Baseline characteristics

Click here to view

Table 2: Medication history of study population

Click here to view

Echocardiographic details and baseline electrocardiography

[Table 3] illustrates the baseline ECG and echocardiography details before TAVI. Overall, baseline echocardiography showed that all patients had a mean ejection fraction of 55.5% ± 9.7%, and a slightly lower mean ejection fraction of 52.5% ± 9.6% was seen in the new-onset LBBB group than in the group without new onset LBBB (56.8% ± 9.5%, P = 0.116). The left ventricular hypertrophy was seen in 49/61 (80.3%) patients, with similar incidences in the groups with and without new-onset LBBB, 15/18 (83.3%) and 34/41 (79.1%), respectively (P = 0.702). Other valve disorders were assessed, including aortic and tricuspid regurgitation, with incidences of 27.9% and 42.6%, respectively (P = 0.214, P = 0.451). Systolic dysfunction was observed in 9/61 patients (14.8%), with a higher incidence in the new-onset LBBB group (5/18, 27.8%, P = 0.063). Diastolic dysfunction was seen in 42/61 patients (68.9%), occurring at a higher rate in the new-onset LBBB group (15/18, 83.3%, P = 0.114). The mean peak gradient, aortic velocity, and aortic valve area were 74.2 ± 17.5 mmHg, 4.3 ± 0.5 m/s, and 0.8 ± 0.2 cm², respectively (P = 0.645, P = 0.384, P = 0.087).

Table 3: Echocardiographic and baseline electrocardiographic detail

Click here to view

Baseline ECG of patients showed normal sinus rhythm in 40/61 (66.7%) higher in group without new-onset persistent LBBB 31/41 (72.1%). Atrial fibrillation was seen in 16/61 (26.7%), preexisting LBBB was seen in 3/61 (5%), and AV nodal re-entrant tachycardia was seen in a single new-onset LBBB patient. Overall, none of the abovementioned data demonstrated any association with new-onset LBBB development post-TAVI.

Computed tomography details

[Table 4] illustrates the CT details and aortic valve dimensions. Overall, the mean maximum leaflet length was 17 ± 3.7 mm in all patients, and a slightly longer leaflet (mean maximum leaflet length = 17.5 ± 2 mm) was seen in new-onset LBBB patients (P = 0.641). The majority of patients had severe calcification (31/61, 50.8%, P = 0.218). The mean short axis and long axis diameters were 21.8 ± 2.5 mm and 26.8 ± 3.3 mm, respectively (P = 0.782, 0.495). The mean annular circumference and annular area were 76.8 ± 7.6 mm and 464.7 ± 100.3 mm², respectively (P = 0.774, P = 0.891). The mean sinotubular junction diameter was 25.8 ± 3.5 mm (P = 0.707). The height of valsalva and area of sinus valsalva were 22 ± 4 mm and 742.2 ± 204.6 mm², respectively (P = 0.713, 0.239). Last, the distances to the left coronary artery and right coronary artery were 12.9 ± 2.8 mm and 15 ± 3.4 mm, respectively (P = 0.611, 0.709). All the above-mentioned data showed no association with new-onset LBBB development post-TAVI.

Table 4: Computed tomography findings preprocedure

Click here to view

Posttranscatheter aortic valve implantation outcomes

Postprocedural records and ECGs were collected and are illustrated in [Table 5]. A total of 7/61 (11.5%) underwent PPI, 4/43 (9.3%) were without new-onset LBBB patients, and 3/18 (16.7%) were new-onset LBBB patients (P = 0.063). Single mortality occurred in a patient with new-onset LBBB (mortality rate = 1.6%, P = 0.119), where the LBBB progressed to 2:1 heart block, cardiogenic shock, and asystole.

Table 5: Posttranscatheter aortic valve implantation outcomes and posttranscatheter aortic valve implantation electrocardiographic data

Click here to view

Postprocedural ECG records were assessed for new-onset conduction abnormalities. The incidence of the right bundle branch block was 4/61 (6.6%), and the majority occurred in the group without new-onset LBBB 3/43 (7%, P = 0.838). The incidence of 1^st degree AV block was 4/61 (6.6%), exclusively in the new-onset LBBB patients (P = 0.001). In addition, the total incidence of complete heart block was 5/61 (8.2%), 4/43 (9.3%) in the group without new-onset LBBB and 1/18 (5.6%) in the new-onset LBBB group (P = 0.627). Furthermore, 2^nd degree AV block and bifasicular block had a single case each (1.6%). The incidence of atrial fibrillation was 4/61 (6.6%) in the majority of patients in the group without new-onset LBBB (3/43, 7%).

Discussion

In our study, the incidence of new-onset LBBB post-TAVI was 18/61 (29.5%). Possible predictors of this complication were explored by analyzing the following: First, patient characteristics, including age, sex, and cardiovascular history; second, echocardiography, baseline, and post-TAVI ECG, and CT of aortic valve dimensions were assessed and showed no association with new-onset LBBB development. In terms of hospital outcomes, the total incidence of PPI was 9/61 (14.8%), and the incidence was higher in the new-onset LBBB group (5/18, 27.8%) than in the group without new-onset LBBB (4/43, 9.3%) (P = 0.063). In addition, the incidence of complete AV block was higher in the group without new-onset LBBB 4/43 (9.3%, P = 0.627), explaining the need for PPI in this group. Furthermore, 1^st degree AV block was seen exclusively in the new-onset LBBB group (4/18, 22.2%, P = 0.001), indicating that LBBB is likely to progress to 1^st degree AV block. A single mortality was recorded in the new-onset LBBB group, and records showed that this patient progressed further into a 2:1 heart block and developed new ST-T changes followed by cardiogenic shock leading to asystole.

Conduction dysfunction is the most common complication following TAVI, and the incidence usually ranges between 30% and 50%.^{[1],[2],[12],[13]} This can be explained by the proximity of the aortic valve to the conduction system and the superficial position of the left bundle branch in the interventricular septum.^[14],[15] During the procedure, injury occurs due to stress applied to the interventricular septum by prosthesis skirt during valve expansion, balloon predilation, or guidewire insertion.^[15],[16] In terms of outcomes, patients who develop new-onset LBBB are more likely to receive PPI, the main indication being the development of a complete AV block.^{[1],[6],[16],[17]} In addition, the mortality rate is generally higher in the new-onset LBBB group because the LBBB interferes with left ventricular function improvement and leads to ventricular dysynchrony and heart failure.^[14],[15]

Other studies have established possible predictors of new-onset LBBB development post-TAVI, divided into procedure-related and patient-related predictors. The most important procedure-related predictor is the type of device used in implantation. Irene et al. established that LBBB development was more frequent in the Medtronic CoreValve Revalving System than in the Edward SAPIEN system, with incidences of 50% and 13.5%, respectively, because of the longer bioprosthesis frame of MCRS.^{[13],[18],[19]} In addition, Irene et al. and Urena et al. both found that lower ventricular positioning or deeper implantation of bioprosthesis is associated with a higher risk of LBBB.^{[18],[19],[20],[21]} Furthermore, Gutierrez et al. found that a greater oversizing of the balloon during valve implantation was associated with a higher risk of LBBB development.^[12] Conversely, patient-related predictors such as a longer QRS duration pre-TAVI were found to increase susceptibility for conduction dysfunction according to Urena et al.^[19],[20] Last, the extent of calcification in the aortic valve was found to increase the risk for LBBB development post-TAVI according to Thomas et al.^[22]

The limitations of our study are as follows. First, as it is a pilot study, the cohort chosen was limited. Second, only a single type of TAVI system was used, which is the ESV system; thus, we were not able to compare the incidence of LBBB post-TAVI in other systems. Last, there were no intraoperative data regarding details of the procedure in the database, such as the depth of implantation; thus, we were not able to explore intra-procedural predictors of LBBB development.

Conclusion

In severe symptomatic aortic stenosis patients, who underwent TAVI, 29.5% developed new-onset persistent LBBB. Many parameters have been explored in our study to assess the predictors of such complications; however, none showed any association with new-onset LBBB development. In terms of outcomes, the new-onset LBBB group had a higher incidence of PPI (27.8%), with the main indication being progression to complete heart block.

Data availability statement

The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.

Ethics approval statement

This study was approved by the Ethics Committee and Ministry of Health Kuwait.

Patient consent statement

Patient consented was not mandated for this retrospective observational study. Permission to reproduce material from other sources: No material from other sources is included in this study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Houthuizen P, Van Garsse LA, Poels TT, de Jaegere P, van der Boon RM, Swinkels BM, et al. Left bundle-branch block induced by transcatheter aortic valve implantation increases risk of death. Circulation 2012;126:720-8.
2.	Urena M, Rodés-Cabau J. Managing heart block after transcatheter aortic valve implantation: From monitoring to device selection and pacemaker indications. EuroIntervention 2015;11 Suppl W:W101-5.
3.	Lichtenstein SV, Cheung A, Ye J, Thompson CR, Carere RG, Pasupati S, et al. Transapical transcatheter aortic valve implantation in humans: Initial clinical experience. Circulation 2006;114:591-6.
4.	Al Balool J, Rajan R, Al Jarallah M, Dashti R, Al Mulla K, Al Haroun R, et al. Aortic stenosis: From diagnosis to treatment: A review (2021 update). Ann Clin Cardiol 2021;3:54-62.
5.	Godin M, Eltchaninoff H, Furuta A, Tron C, Anselme F, Bejar K, et al. Frequency of conduction disturbances after transcatheter implantation of an Edwards Sapien aortic valve prosthesis. Am J Cardiol 2010;106:707-12.
6.	Sinhal A, Altwegg L, Pasupati S, Humphries KH, Allard M, Martin P, et al. Atrioventricular block after transcatheter balloon expandable aortic valve implantation. JACC Cardiovasc Interv 2008;1:305-9.
7.	Chamandi C, Barbanti M, Munoz-Garcia A, Latib A, Nombela-Franco L, Gutiérrez-Ibanez E, et al. Long-term outcomes in patients with new-onset persistent left bundle branch block following TAVR. JACC Cardiovasc Interv 2019;12:1175-84.
8.	Urena M, Webb JG, Cheema A, Serra V, Toggweiler S, Barbanti M, et al. Impact of new-onset persistent left bundle branch block on late clinical outcomes in patients undergoing transcatheter aortic valve implantation with a balloon-expandable valve. JACC Cardiovasc Interv 2014;7:128-36.
9.	Hayashidani S, Shiose A, Tsutsui H. New-onset left bundle branch block after transcatheter aortic valve implantation – Not a harmless bystander. Circ J 2020;84:888-90.
10.	Zannad F, Huvelle E, Dickstein K, van Veldhuisen DJ, Stellbrink C, Køber L, et al. Left bundle branch block as a risk factor for progression to heart failure. Eur J Heart Fail 2007;9:7-14.
11.	Balool JA, Jarallah MA, Rajan R, Dashti R, Alasousi N, Koteivski V, et al, Clinical outcomes of transcatheter aortic valve replacement stratified by left ventricular ejection fraction: A single centre pilot study. Annals of Medicine and Surgery 2022;77:103712, https://doi.org/10.1016/j.amsu.2022.103712.
12.	Gutiérrez M, Rodés-Cabau J, Bagur R, Doyle D, DeLarochellière R, Bergeron S, et al. Electrocardiographic changes and clinical outcomes after transapical aortic valve implantation. Am Heart J 2009;158:302-8.
13.	Santos M, Lamas C, Azevedo F, Colafranceschi A, Weksler C, Rodrigues L, et al. Incidence of conduction disorders and requirements for permanent pacemaker after transcatheter aortic valve implantation. Int J Cardiovasc Sci 2019;33:1364-72.
14.	Roten L, Wenaweser P, Delacrétaz E, Hellige G, Stortecky S, Tanner H, et al. Incidence and predictors of atrioventricular conduction impairment after transcatheter aortic valve implantation. Am J Cardiol 2010;106:1473-80.
15.	Auffret V, Puri R, Urena M, Chamandi C, Rodriguez-Gabella T, Philippon F, et al. Conduction disturbances after transcatheter aortic valve replacement: Current status and future perspectives. Circulation 2017;136:1049-69.
16.	Bleiziffer S, Ruge H, Hörer J, Hutter A, Geisbüsch S, Brockmann G, et al. Predictors for new-onset complete heart block after transcatheter aortic valve implantation. JACC Cardiovasc Interv 2010;3:524-30.
17.	Walther T, Manoharan G, Linke A, Möllmann H, Holzhey D, Worthley SG, et al. Incidence of new-onset left bundle branch block and predictors of new permanent pacemaker following transcatheter aortic valve replacement with the Portico™ valve. Eur J Cardiothorac Surg 2018;54:467-74.
18.	Franzoni I, Latib A, Maisano F, Costopoulos C, Testa L, Figini F, et al. Comparison of incidence and predictors of left bundle branch block after transcatheter aortic valve implantation using the CoreValve versus the Edwards valve. Am J Cardiol 2013;112:554-9.
19.	Colombo A, Latib A. Left bundle branch block after transcatheter aortic valve implantation: Inconsequential or a clinically important endpoint? J Am Coll Cardiol 2012;60:1753-5.
20.	Urena M, Mok M, Serra V, Dumont E, Nombela-Franco L, DeLarochellière R, et al. Predictive factors and long-term clinical consequences of persistent left bundle branch block following transcatheter aortic valve implantation with a balloon-expandable valve. J Am Coll Cardiol 2012;60:1743-52.
21.	Piazza N, Onuma Y, Jesserun E, Kint PP, Maugenest AM, Anderson RH, et al. Early and persistent intraventricular conduction abnormalities and requirements for pacemaking after percutaneous replacement of the aortic valve. JACC Cardiovasc Interv 2008;1:310-6.
22.	Poels TT, Houthuizen P, Van Garsse LA, Maessen JG, de Jaegere P, Prinzen FW. Transcatheter aortic valve implantation-induced left bundle branch block: Causes and consequences. J Cardiovasc Transl Res 2014;7:395-405.