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 Table of Contents  
ORIGINAL ARTICLE
Year : 2019  |  Volume : 4  |  Issue : 1  |  Page : 20-25

Intracardiac echocardiography-guided left bundle branch pacing


Department of Cardiology, The First People's Hospital of Yunnan Province, Affiliated Hospital of Medical School of Kunming University of Science and Technology, Arrhythmia Research Center, Kunming, Yunnan Province, China

Date of Web Publication25-Nov-2019

Correspondence Address:
Dr. Jie Fan
Department of Cardiology, The First People's Hospital of Yunnan Province, Affiliated Hospital of Medical School of Kunming University of Science and Technology, Arrhythmia Research Center, Kunming 650032, Yunnan Province
China
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/IJHR.IJHR_6_19

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  Abstract 

Background: The aim of this study is to investigate the role and method of intracardiac echocardiography (ICE) in left bundle branch pacing. Subjects and Methods: A total of 12 patients who underwent ICE-guided left bundle branch pacing from February 2018 to June 2018 in the Department of Cardiology of the First People's Hospital of Yunnan Province were enrolled in this observational case analysis. The study was approved by the Institutional Ethical Committee of the First People's Hospital of Yunnan Province, China (approval No. KHLL2019-KY018). The patients' sex, age, weight, disease history, and the results of color Doppler echocardiography were recorded before surgery. The duration of surgery, X-ray exposure, pacing parameters (threshold, perception, and impedance), electrocardiogram characteristics, pacing parameters, clinical symptoms, and echocardiographic results were recorded after surgery. Results: The left bundle branch pacing guided by ICE was successfully in all 12 patients. There were four cases of sick sinus syndrome, six cases of atrioventricular block, and two cases of atrial fibrillation with long R-R interval. The mean operation time was 1.75 ± 0.28 hours, and the X-ray exposure was 61.2 ± 13.6 mGy. The implantation time of left bundle branch electrode was 1.23 ± 0.24 hours, and X-ray exposure of left bundle branch electrode implantation was 48.9 ± 12.3 mGy. There was no electrode dislocation, pneumothorax, or infection after operation. Two of them had a small hematoma of the pacemaker pocket, and hematoma disappeared after compression. Conclusion: This study demonstrates the feasibility of ICE guidance for left bundle branch pacing, which may increase the success rate and reduce the risk of surgery.

Keywords: Artificial, cardiac pacing, intracardiac echocardiography, left bundle branch


How to cite this article:
Kuang X, Zhang X, Gao X, Wang L, Ding L, Zhang J, Xiang H, Guo J, Gao T, Wei F, Fan J. Intracardiac echocardiography-guided left bundle branch pacing. Int J Heart Rhythm 2019;4:20-5

How to cite this URL:
Kuang X, Zhang X, Gao X, Wang L, Ding L, Zhang J, Xiang H, Guo J, Gao T, Wei F, Fan J. Intracardiac echocardiography-guided left bundle branch pacing. Int J Heart Rhythm [serial online] 2019 [cited 2019 Dec 16];4:20-5. Available from: http://www.ijhronline.org/text.asp?2019/4/1/20/271666


  Introduction Top


Since 1958, the first pacemaker has been successfully implanted in the human body. In the past 60 years, great changes have taken place in pacemaker pulse generator, pacemaker leads, and implantation techniques. Currently, right ventricular apical pacing is widely used in clinical practice due to its strong operability and leads' stability. However, many studies have shown that right ventricular apical pacing is not an ideal pacing method because the sequence of ventricular activation during apical pacing is contrary to that of physiological pacing which may result in potential deterioration of cardiac function, valvular dysfunction, arrhythmia, and high mortality rate in particular populations.[1] Left bundle branch pacing may have advantages in operability and safety. At present, X-ray fluoroscopy and potential are routinely used to determine the location of implantation. The depth of lead implantation mainly depends on the operator's experience and electrocardiogram (ECG) characteristics. In this study, ventricular lead implantation was guided by intracardiac echocardiography (ICE) in order to explore the role of ICE in left bundle branch pacing.


  Subjects and Methods Top


Subjects

From February 2018 to June 2018, 102 patients with indications of single-chamber or double-chamber pacemaker implantation in the Department of Cardiology, Yunnan ProvincialFirst People's Hospital, were enrolled, of whom 12 patients received left bundle branch pacing guided by ICE. This observational case study was approved by the Institutional Ethical Committee of theFirst People's Hospital of Yunnan Province, China (approval No. KHLL2019-KY018), and performed in line with the 2013 Revision of the Declaration of Helsinki, and patients or their family members signed an informed consent form. A serial of data were registered: preoperative routine registration of sex, age, body weight, history of disease, liver and kidney function, and echocardiographic results; intraoperative recording of operation time, X-ray exposure, pacing parameters (threshold, perception, and impedance); and postoperative cardiac recording of ECG characteristics, pacing parameters, clinical symptoms, and echocardiographic results.

Operation methods

The operation was performed in the catheterization room of the department of cardiology. Angiography machine (General Motors, USA), electrophysiological polygraph (EP4, Abbott), three-dimensional electrophysiological navigator (Carto3, Johnson and Johnson), and color Doppler ultrasonic machine (General Motors) were prepared conventionally. The patient laid flat on the bed of the catheter room, connected with Carto3 positioning patch and 12-lead ECG which was connected to the electrophysiological polygraph. The bilateral chest and bilateral inguinal areas were routinely sterilized, and sterile towels were laid. The left subclavian vein was punctured and the guidewire was implanted (one puncture for single-chamber pacemaker and two punctures for double-chamber pacemaker). Fluoroscopy confirmed that the guidewire entered the inferior vena cava. The pacemaker bag was routinely made at the plane of the puncture point. 8F artery sheath was implanted through the guidewire. Long steel wire and delivery catheter (C315HIS, Medtronic) were implanted through 8F artery sheath. The right femoral vein was punctured and ICE was implanted through the 11F artery sheath. Under the guidance of X-ray and ICE, the lead (3830, SelectSecure, Medtronic) was implanted in the left bundle branch pacing site through delivery catheter. Delivery catheter was withdrawn when lead implantation site and parameters were satisfactory. The atrial lead was routinely implanted in the right atrial appendage, then the delivery catheter was removed, and lead was fixed. The pacemaker was connected and the skin was sutured layer by layer. ICE and sheath were removed. The operation was completed after the wound was covered with sterile dressing.

Operation method of intracardiac echocardiography catheter

The imaging plane of ICE catheter (Soundstar, Johnson and Johnson) was located in the “home” position. The clockwise rotation caused the ultrasonic plane to turn to the posterior wall of the right atrium with a foot position of 6:00. The ICE catheter bended the plane backward and upward by adjustingP bends and backcrossed the tricuspid annulus into the right ventricle. The ICE catheter was attached to the ventricular free wall by slight reverse clock rotation, and the catheter was pressed down by adjusting the L bend until the interventricular septum and left and right ventricles were displayed, and the R bend was fine-tuned to construct a three-dimensional model of the interventricular septum [Figure 1]. The lead was actively fixed in the right ventricular septum through the delivery catheter, and the ICE catheter was used to find the position of the lead in the interventricular septum and adjust the lead and sheath to a satisfactory position [Figure 2]. At this time, V1 lead was likely to be QS type, and the ascending branch had notch [Figure 3]. The lead was actively fixed into the interventricular septum, and ICE catheter could observe whether the lead rotated to the subintima of the left ventricle in real time [Figure 4] and measured the distance from the top of the lead to the intima of the left ventricle. The distance between the top of the lead and the attachment point of mitral valve and the length of the interventricular septum were measured to count the location where the lead was located in the interventricular septum (one-third of the interventricular septum near the annulus was the upper segment, one-third of the interventricular septum near the apex was the lower segment, and the middle part was the middle segment). When the lead was twisted to the endocardium of the left ventricle, the left bundle branch potential could be recorded in some patients [Figure 5]. The ECG showed incomplete right bundle branch block after pacing, and the V1 lead was QR type [Figure 6], suggesting that ventricular pacing captured the left bundle branch. The total operation time was from the beginning of local anesthesia to the completion of surgical wound suture. The time from the implantation of the delivery catheter to the successful implantation of the left bundle branch lead and the successful withdrawal of the delivery catheter was the time of the left bundle branch lead implantation. The X-ray exposure required to complete the whole operation was recorded as the total X-ray exposure, and the X-ray exposure from the implantation of the delivery catheter to the successful implantation of the left bundle branch lead and the successful withdrawal of the delivery catheter was recorded as the X-ray exposure of the left bundle branch pacing. The active fixed pacing lead was screwed until the left bundle branch pacing is satisfactory. If there was no need to withdraw the active fixed pacing lead during the first attempt, the time of screwing was recorded as once. If there was the need to withdraw the active fixed pacing lead or reposition, the time of screwing was recorded as twice.
Figure 1: Left and right ventricle and interventricular septum plane. (a) Intracardiac echocardiographic plane shows the left and right ventricles and interventricular septum. (b) The right anterior oblique position and left anterior oblique position show the position of the right ventricular model, the ultrasonic catheter, and the ultrasonic plane. The ultrasonic catheter is located in the right ventricle and the ultrasonic plane points to the septum. RV = Right ventricle, LV = Left ventricle, RAO = Right anterior oblique, LAO = Left anterior oblique, V = Site of ultrasonic probe, 5 = 5 cm away from ultrasonic probe, 10 = 10 cm away from ultrasonic probe

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Figure 2: Pacing lead and interventricular septum. (a) Intracardiac echocardiographic plane shows the left and right ventricles and interventricular septum, and the ventricular electrode is attached to the right ventricular surface of the interventricular septum (indicated by a small white arrow). (b) The right anterior oblique position and left anterior oblique position show the position of the right ventricular model, the ultrasonic catheter, and the ultrasonic plane. The ultrasonic catheter is located in the right ventricle and the ultrasonic plane points to the septum. RV = Right ventricle, LV = Left ventricle, PE = Pacing lead, RAO = Right anterior oblique, LAO = Left anterior oblique, V = Site of ultrasonic probe, 5 = 5 cm away from ultrasonic probe, 10 = 10 cm away from ultrasonic probe

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Figure 3: Electrocardiogram of right ventricular septal pacing, suggesting left bundle branch conduction block, of which V1 lead is QS type, and the ascending branch has notch. ABL = The unipolar electrocardiogram recorded from the top of the left bundle branch lead

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Figure 4: The top of the pacing lead enters the subintima of the left ventricle. (a) Intracardiac echocardiographic plane shows the left and right ventricles and the interventricular septum, and the ventricular lead enters the middle layer of the interventricular septum. (b) The right anterior oblique position and left anterior oblique position show the position of the right ventricular model, the ultrasonic catheter, and the ultrasonic plane. The ultrasonic catheter is located in the right ventricle and the ultrasonic plane points to the septum. RV = Right ventricle, LV = Left ventricle, PE = Pacing lead, RAO = Right anterior oblique, LAO = Left anterior oblique, V = Site of ultrasonic probe, 5 = 5 cm away from ultrasonic probe, 10 = 10 cm away from ultrasonic probe

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Figure 5: The Purkinje potential recorded by the ventricular electrode to the left ventricular surface. This figure shows the pattern of the patient's own electrocardiogram, and the last line is the Purkinje potential recorded from the pacing lead screwing from the interventricular septum to the intima of the left ventricle. ABL-d = The unipolar electrocardiogram recorded from the top of the left bundle branch lead

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Figure 6: The pacing electrocardiogram of ventricular pacing lead rotatinginto the left ventricular intima of the interventricular septum suggests incomplete right bundle branch block with QRS duration of 100 ms and V1 lead displaying QR type. ABL-d = The unipolar electrocardiogram recorded from the top of the left bundle branch lead

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Follow-up methods

Postoperative outpatient or telephone follow-up was used to define discomfort symptoms, to acquire pacemaker pacing parameters 3 months after operation by pacemaker programming, to achieve echocardiography data 3 months after operation.

Statistical analysis

SPSS version 19.0 statistical software (IBM, Armonk, NY, USA) was used for statistical processing. The measurement data conforming to normal distribution were represented by the mean ± standard deviation and one-way analysis of variance was used; the nonnormal distribution data were tested by rank-sum test. The classification variables and the incidence of clinical events in each group were compared by Chi-square test. A difference with P < 0.05 was defined as statistically significant.


  Results Top


Baseline patient characteristics

Twelve patients underwent left bundle branch pacing under the guidance of ICE, with an average age of 64.25 ± 14.65 years and body mass index of 23.9 ± 35 kg/m2, including five males (41.7%). There were four cases of sick sinus syndrome (33.3%), six cases of atrioventricular block (50.0%), and two cases of atrial fibrillation (AF) combined with long RR interval (16.7%). Hypertension occurred in seven cases (58.3%), two cases of which had diabetes mellitus, coronary heart disease (25.0%) occurred in three cases, and AF occurred in two cases (16.7%). Before operation, the left ventricular ejection fraction was 60 ± 8%, the left ventricular end-diastolic diameter was 50.00 ± 4.80 mm, and the baseline QRS duration was 13260 ± 26.60 ms.


  Operation Results Top


All of the 12 patients successfully completed the operation and were successfully implanted the left bundle branch pacing lead. Among them, ten patients were implanted with dual-chamber pacemaker and two patients with AF complicated with long RR interval were implanted with single-chamber pacemaker. The total operation time was 1.75 ± 0.28 hours, and the total X-ray exposure was 61.20 ± 13.60 mGy. The implantation time of left bundle branch lead was 1.23 ± 0.24 hours, X-ray exposure of which was 48.90 ± 12.30 mGy. In all patients, left bundle branch pacing was performed under the guidance of ICE. In 7 (58%) of the 12 patients, the lead could be implanted successfully once, and the other 5 patients needed to adjust or replace the delivery catheter because of the different axes of the delivery catheter. The duration of intraoperative QRS was shorter than that of baseline, and the difference was significant (110.20 ± 9.35 ms vs. 132.60 ± 26.6 ms, P = 0.017); the duration of QRS at 3 months after operation was shorter than that at baseline (106.80 ± 10.20 ms vs. 132.60 ± 26.60 ms, P = 0.003). There was no significant difference in QRS duration between intraoperative and postoperative 3 months (P > 0. 13) [Table 1]. Lead dislocation, pneumothorax, and infection did not occur after operation. Two cases occurred bleeding resulting in slight pocket hematoma, which was absorbed after compression.
Table 1: Intraoperative and postoperative follow-up data of left bundle branch pacing

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  Discussion Top


Cardiac pacing is an effective method for the treatment of patients with bradycardia and cardiac conduction dysfunction. After many years of clinical practice, it has been found that right ventricular apical pacing can cause ventricular activation to be out of sync and then cause ventricular mechanical activity to be out of sync, resulting in a decrease in cardiac function.[1] There have been studies to explore whether interventricular septal pacing or right ventricular outflow tract pacing can replace right ventricular apical pacing, but its advantages have not been confirmed. Cardiac resynchronization therapy began in the early 21st century, and its clinical benefits have been confirmed in specific patients with ventricular asynchrony. However, there is no clear clinical benefit in patients with narrow QRS wave (<120 ms),[2] and the incidence of cardiac resynchronization therapy nonresponse is still as high as 20% to 30%.[3],[4] At present, the category of physiological pacing more and more points to the self-conduction system below the site of pacing block, in order to maximize the maintenance or correction of the synchronization of cardiac electromechanical activity below the site of pacing block, so as to reduce or improve the occurrence of heart failure. Although His bundle pacing is the most physiological pacing mode at present, of which pacing threshold is usually high causing fear of long-term safety, which limits the use of His bundle pacing in patients with all pacing indications, especially in patients with block site below or away from His bundle such as atrioventricular block below His bundle and left bundle branch block. His bundle pacing cannot achieve long-term stable low threshold across the block site for the patients above. Vijayaraman et al.[5] reported that the success rate of His bundle pacing in patients with atrioventricular block below His bundle was only 76%, while the average success rate of left bundle branch block corrected by His bundle pacing was about 70%. Moreover, the correction threshold is relatively high (the average correction threshold is 1.88–3.8 V). For such patients, how to safely and physiologically achieve conduction bundle pacing across the block site? Deeper and further pacing of conduction bundle below the block site is undoubtedly the best solution. Huang et al.[6] reported a case of left bundle branch pacing, which aroused the attention of electrophysiologists to left bundle branch pacing. The distribution of conduction bundles in the septal plane of the left ventricle is reticular. There is a great difference among individuals, so the bundle branches captured by pacing were different. The left anterior branch or the left posterior branch or further left Purkinje system is currently collectively referred to as the left bundle branch area. Cardiac electrical activity conducts along the His-Purkinje system, which enables the ventricle to contract synchronously and effectively, thus maintaining cardiac output.[7] Therefore, there is no doubt that if pacing therapy can make the use of and maintain the function of the His-Purkinje system, it can achieve the real sense of physiological pacing. At present, a number of single-center studies have confirmed that His bundle and His bundle branch pacing are clinically feasible,[8] of which clinical benefit and security are guaranteed in patients with heart failure.[9] The main technical point of left bundle branch pacing is to locate the pacing lead in the left bundle branch area.[10] At present, its localization mainly depends on X-ray and intracavitary ECG, combined with ECG localization after pacing, with the lack of intuitive and reliable imaging methods during operation.

ICE can real-time display the position of the pacing lead in the cardiac cavity and can clearly show the depth of the lead into the myocardium. In this study, it was found that all the successful left bundle branch pacing leads were located in the middle of the interventricular septum and close to the endomembrane surface of the left ventricle, which may be related to the distribution of the left His-Purkinje system close to the intima of the left ventricle. ICE reconstructs the three-dimensional model of the cardiac cavity by outlining the structure of the cardiac cavity seen by each two-dimensional ultrasound. ICE is widely used in electrophysiological operation, especially in some special parts of arrhythmias, such as papillary muscle-related ventricular arrhythmias. Animal experiments of His bundle pacing using ICE have been reported, but no reports have been reported in humans.[3] At present, the His-Purkinje system pacing is widely carried out, especially the left bundle branch pacing. Active fixation of pacing leads often needs to be twisted to the left bundle branch area, and ordinary X-ray fluoroscopy cannot determine the depth of the lead into the myocardium, thus increasing the difficulty and risk of surgery.[11],[12],[13],[14],[15] ICE can be helpful to complete the His-Purkinje system pacing, especially the left bundle branch pacing under “direct vision,” which can clearly locate the lead under the intima of the left ventricle of the interventricular septum and prevent the lead from penetrating the interventricular septum into the left ventricle resulting in increase of success rate and security. In this study, about 67% of the patients were able to record the Purkinje potential of the left ventricle after the lead was implanted into the subintima of the left ventricle, which was similar to the probability reported by the domestic counterparts.[8]

Limitations

At present, there is no unified standard for the determination of left bundle branch pacing, and some of the cases in this study may only be pacing on the left side of the interventricular septum. ICE can improve the success rate and safety of His-Purkinje system pacing, but the cost is high, and may increase the risk of femoral vein puncture complications and pacemaker infection, which may be difficult to be used routinely in clinical practice.


  Conclusion Top


Feasibility of ICE guidance for left bundle branch pacing was demonstrated in this study, which may increase the success rate and reduce the risk of surgery.

Financial support and sponsorship

This work was supported by the Funds for Research Institute of Yunnan Province in 2017 (2017NS252 and 2017NS253) and the Funds for Research Institute of Yunnan Province in 2018 (2018NS0267 and 2018NS0268).

Conflicts of interest

There are no conflicts of interest.

Institutional review board statement

The study was approved by the Institutional Ethical Committee (IEC) of theFirst People's Hospital of Yunnan Province, China (approval No. KHLL2019-KY018).

Declaration of patient consent

The authors certify that they have obtained all appropriate consent from patients or their family members. In the forms, the patients or their family members have given their consent for the patients' images and other clinical information to be reported in the journal. The patients or their family members understand that the patients' names and initials will not be published and due efforts will be made to conceal their identity forms.

 
  References Top

1.
Merchant FM, Mittal S. Pacing-induced cardiomyopathy. Card Electrophysiol Clin 2018;10:437-45.  Back to cited text no. 1
    
2.
Steffel J, Robertson M, Singh JP, Abraham WT, Bax JJ, Borer JS, et al. The effect of QRS duration on cardiac resynchronization therapy in patients with a narrow QRS complex: A subgroup analysis of the EchoCRT trial. Eur Heart J 2015;36:1983-9.  Back to cited text no. 2
    
3.
Zhang B, Guo J, Zhang G. Comparison of triple-site ventricular pacing versus conventional cardiac resynchronization therapy in patients with systolic heart failure: A meta-analysis of randomized and observational studies. J Arrhythm 2018;34:55-64.  Back to cited text no. 3
    
4.
Shanks M, Delgado V, Ng AC, Auger D, Mooyaart EA, Bertini M, et al. Clinical and echocardiographic predictors of nonresponse to cardiac resynchronization therapy. Am Heart J 2011;161:552-7.  Back to cited text no. 4
    
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Vijayaraman P, Naperkowski A, Ellenbogen KA, Dandamudi G. Electrophysiologic insights into site of Atrioventricular block: Lessons from permanent his bundle pacing. JACC Clin Electrophysiol 2015;1:571-81.  Back to cited text no. 5
    
6.
Huang W, Su L, Wu S, Xu L, Xiao F, Zhou X, et al. Anovel pacing strategy with low and stable output: Pacing the left bundle branch immediately beyond the conduction block. Can J Cardiol 2017;33:1736.e1-00.  Back to cited text no. 6
    
7.
Massing GK, James TN. Anatomical configuration of the his bundle and bundle branches in the human heart. Circulation 1976;53:609-21.  Back to cited text no. 7
    
8.
Chen K, Li Y, Dai Y, Sun Q, Luo B, Li C, et al. Comparison of electrocardiogram characteristics and pacing parameters between left bundle branch pacing and right ventricular pacing in patients receiving pacemaker therapy. Europace 2019;21:673-80.  Back to cited text no. 8
    
9.
Shan P, Su L, Zhou X, Wu S, Xu L, Xiao F, et al. Beneficial effects of upgrading to his bundle pacing in chronically paced patients with left ventricular ejection fraction and lt; 50. Heart Rhythm 2018;15:405-12.  Back to cited text no. 9
    
10.
Yin L, Laske TG, Rakow N, Cai L, Williams T, Li C, et al. Intracardiac echocardiography-guided his bundle pacing and atrioventricular nodal ablation. Pacing Clin Electrophysiol 2008;31:536-42.  Back to cited text no. 10
    
11.
Ji R, Tao N, Qiu Y, Wang Y, Qian Z, Shi L, et al. R on T pacing phenomenon after his bundle pacing in patients with chronic atrial fibrillation and slow ventricular response. Zhonghua Xinlv Shi Chang Za Zhi 2017;21:234-7.  Back to cited text no. 11
    
12.
Vijayaraman P, Dandamudi G, Worsnick S, Ellenbogen KA. Acute his-bundle injury current during permanent his-bundle pacing predicts excellent pacing outcomes. Pacing Clin Electrophysiol 2015;38:540-6.  Back to cited text no. 12
    
13.
Abdelrahman M, Subzposh FA, Beer D, Durr B, Naperkowski A, Sun H, et al. Clinical outcomes of his bundle pacing compared to right ventricular pacing. J Am Coll Cardiol 2018;71:2319-30.  Back to cited text no. 13
    
14.
Huang W, Su L, Wu S, Xu L, Xiao F, Zhou X, et al. Long-term outcomes of his bundle pacing in patients with hear failure with left bundle branch block. Heart 2019;105:137-43.  Back to cited text no. 14
    
15.
Pastore G, Zanon F, Baracca E, Aggio S, Corbucci G, Boaretto G, et al. The risk of atrial fibrillation during right ventricular pacing. Europace 2016;18:353-8.  Back to cited text no. 15
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
 
 
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