Outcomes of Self-Expanding vs. Balloon-Expandable Transcatheter Heart Valves for the Treatment of Degenerated Aortic Surgical Bioprostheses　― A Propensity Score-Matched Comparison ―

Abstract

Background: Transcatheter aortic valve-in-valve (VIV) replacement within failed bioprosthetic surgical aortic valves is a feasible therapeutic option. However, data comparing the hemodynamic and clinical outcomes of VIV replacement with supra-annular self-expanding and balloon-expandable transcatheter heart valves (THV) are limited.

Methods and Results: Outcomes of 40 and 95 patients treated with supra-annular self-expanding and balloon-expandable THV, respectively, were compared after propensity score matching, which yielded 37 pairs of patients with similar baseline characteristics. Hemodynamic and clinical outcomes were analyzed. Postprocedural mean gradient was significantly lower in the self-expanding THV group than in the balloon-expandable THV group (12.1±6.1 mmHg vs. 19.0±7.3 mmHg, P<0.001). The incidence of at least mild postprocedural aortic regurgitation (AR) was comparable between the self-expanding and balloon-expandable THV groups (21.6% vs. 10.8%, P=0.39). In the self-expanding THV group, the new-generation THV showed a trend towards a lower incidence of at least mild AR compared with the early-generation THV (12.5% vs. 38.5%, P=0.07). A similar trend was observed in the balloon-expandable THV group (4.2% vs. 23.1%, P=0.08). There was no significant difference between the self-expanding and balloon-expandable THV groups in the cumulative 2-year all-cause mortality rates (22.4% vs. 43.4%, log-rank P=0.26).

Conclusions: The supra-annular self-expanding THV was associated with a lower postprocedural mean gradient compared with balloon-expandable THV in patients undergoing aortic VIV replacement.

Transcatheter aortic valve-in-valve (VIV) replacement within degenerated surgical bioprostheses has become a safe and feasible therapeutic alternative to redo surgery in patients deemed at high risk for open surgery.^1,2 Currently, the main limitation of aortic VIV procedures is high postprocedural gradients.^2,3 Most candidates for VIV replacement can be treated with either self-expanding or balloon-expandable transcatheter heart valves (THV).² Previous observational studies have demonstrated that supra-annular self-expanding THV are associated with lower gradients following VIV procedures than are balloon-expandable THV.^1,2 However, in those studies, there were clear baseline differences between the self-expanding and balloon-expandable THV groups, including the mode of bioprosthesis failure (stenosis vs. regurgitation vs. combined), the true internal diameter (ID) of the surgical valve, and the surgical valve design (stented vs. stentless), all of which are associated with hemodynamic or clinical outcomes. To date, there are no prospective randomized trials or studies comparing matched patients undergoing VIV procedures with self-expanding or balloon-expandable THV. Moreover, previous studies were limited to early-generation THV, and data on new-generation THV are scarce.

Bioprosthetic surgical valves are increasingly used in preference to mechanical valves for surgical aortic valve replacement (SAVR), particularly in younger populations, which has been largely driven by patients seeking to avoid lifelong anticoagulant therapy and the possibility of future transcatheter VIV implantation.⁴ Accordingly, the number of VIV procedures is likely to increase and thus, an enhanced understanding of the differences in the hemodynamic and clinical outcomes of VIV replacement when using self-expanding and balloon-expandable THV may serve to optimize device selection.

In this study, we aimed to compare the hemodynamic and clinical outcomes of supra-annular self-expanding and balloon-expandable THV systems for aortic VIV replacement in propensity score-matched populations.

In addition, the differences in outcomes between self-expanding and balloon-expandable THV were analyzed, accounting for the generation (early or new) of the THV.

Methods

Study Population

Between February 2012 and August 2017, patients undergoing transcatheter VIV replacement for failed aortic surgical bioprosthetic valves at Cedars-Sinai Medical Center were included in the database.

For the purpose of the present analysis, patients were categorized into either the supra-annular self-expanding THV or balloon-expandable THV group, and the hemodynamic and clinical outcomes were compared between the groups. The supra-annular self-expanding THV that were available during the study period were the CoreValve and Evolut R (Medtronic, Minneapolis, MN, USA) prostheses, and the balloon-expandable THV were the SAPIEN, SAPIEN XT, and SAPIEN 3 (Edwards Lifesciences, Irvine, CA, USA) prostheses. We further categorized the THV into early-generation (SAPIEN, SAPIEN XT, and CoreValve) and new-generation (SAPIEN 3 and Evolut R). The patients who underwent computed tomography (CT) scanning after transcatheter aortic valve replacement (TAVR) were enrolled in the RESOLVE registry (Assessment of Transcatheter and Surgical Aortic Bioprosthetic Valve Thrombosis and Its Treatment with Anticoagulation: NCT02318342) at Cedars-Sinai Medical Center. The institutional review board approved the study and informed consent was given by all patients.

Study Devices and Procedure

The decision to proceed with transcatheter VIV replacement was made with the consensus of a dedicated heart team including experienced clinical and interventional cardiologists and cardiovascular surgeons. THV sizing was determined by smartphone application-based sizing data,⁵ manufacturer’s tables, 3D multidetector-row CT-based annular measurements, and expert consensus. The true ID of the surgical valves was derived according to the valve type and label size.⁶ In the case of VIV replacement in extremely small surgical valves (true ID ≤17 mm), the 20-mm SAPIEN XT or SAPIEN 3 tended to be selected because the true ID is considerably smaller than the lower limit of size of self-expanding THV.

Echocardiographic, Fluoroscopic and CT Analyses

Standard 2D B-mode and Doppler transthoracic echocardiography was performed at baseline and prior to hospital discharge, and conventional echocardiographic parameters were measured according to the American Society of Echocardiography (ASE) guidelines.^7,8 The mechanism of bioprosthetic valve failure (i.e., stenosis or regurgitation) was also evaluated according to the ASE criteria.⁹ Patients with at least a moderate degree of both stenosis and regurgitation were included in the combined group. Other patients were categorized according to the primary mechanism of failure (stenosis or regurgitation). The degree of total aortic regurgitation (AR) after TAVR was measured in accordance with current guidelines⁷ and categorized using a semiquantitative grade as none, trace, mild, moderate, or severe.

Post-implantation angiographic images were analyzed for THV depth assessment. Self-expanding THV depth was expressed in millimeter(s), reflecting the distance of the THV distal frame in relation to the surgical valve frame. High implantation of the self-expanding THV was defined as an implantation depth of ≤5 mm. For the balloon-expandable THV, the depth was defined as the percentage of the THV height below the stented surgical valve ring. High implantation of the balloon-expandable THV was defined as an implantation depth of ≤10% as previously described.¹⁰

As for CT after VIV replacement, the imaging protocol, processing and analysis were performed as previously reported.^11,12

Endpoints and Definitions

The primary endpoint of this study was the postprocedural aortic valve (AV) mean gradient. Secondary endpoints were 30-day major clinical endpoints based on the Valve Academic Research Consortium-2 criteria¹³ and all-cause death at 2 years. Other endpoints included new permanent pacemaker insertion, procedure- and device-related complications, echocardiographic assessment of valve and cardiac function at discharge, and CT evaluation of subclinical leaflet thrombosis after TAVR. Furthermore, we performed a subgroup analysis for the patients treated with early- or new-generation THV because that difference could affect the clinical outcomes.

Data Collection and Outcomes

Data collection included baseline clinical, laboratory, echocardiographic, and CT data, as well as procedural data and clinical follow-up data. Follow-up data was recorded during outpatient visits or telephone interviews at 1, 6 and 12 months, and yearly thereafter.

Statistical Analysis

Data are presented as mean±standard deviation (SD) for normally distributed continuous variables or as median and interquartile range (IQR: 25–75%) for non-normally distributed continuous variables. Categorical variables are expressed as numeric values and percentages. Comparison of categorical variables was performed using the Student t-test or Mann-Whitney U test, depending on the variable distribution. The chi-square test or Fisher’s exact test was used to compare categorical variables. Given the differences in baseline clinical, echocardiographic, and procedural characteristics between the self-expanding and balloon-expandable cases, propensity score matching was applied to identify a cohort of patients with similar baseline characteristics. The propensity score was estimated based on a logistic regression model constructed with the following variables: age, sex, Society of Thoracic Surgeons mortality score, transfemoral approach, surgical valve design (stented vs. stentless), mode of bioprosthesis failure (stenosis vs. regurgitation vs. combined), surgical valve true ID, generation of THV (early vs. new), preoperative left ventricular ejection fraction (LVEF), and AV mean gradient. Patients in the self-expanding THV and balloon-expandable THV groups with the same probability score (nearest neighbor method; caliper width equal to 20% of the SD of the logit of the calculated propensity score) were matched in a 1:1 fashion. The C-statistic of propensity for the logistic model used to generate the propensity score was 0.78 (95% CI: 0.70–0.85), and the Hosmer-Lemeshow test was not significant (P=0.27).

After matching, continuous variables with a normal distribution were compared using the paired sample t-test; otherwise, the Wilcoxon rank-sum test was used. Differences for matched categorical variables were analyzed using McNemar’s test. Kaplan-Meier analysis was performed using the log-rank test to compare survival rates between the self-expanding and balloon-expandable THV groups. In order to assess the predictors of high postprocedural gradient (≥20 mmHg) in the overall cohort, we performed a logistic regression analysis including the following variables: baseline aortic stenosis (AS) ≥moderate, LVEF, stented surgical valve, small surgical valve (true ID <20 mm), balloon-expandable THV, and post-dilatation. All statistical analyses were performed using SPSS version 24.0 (SPSS Inc., Chicago, IL, USA) and R software version 3.2.2 (R Foundation for Statistical Computing, Vienna, Austria). A value of P<0.05 was considered to indicate statistical significance.

Results

Baseline Characteristics

A total of 135 patients with failed aortic surgical bioprosthetic valves were treated with VIV replacement at Cedars-Sinai Medical Center between February 2012 and August 2017: 40 were treated with a supra-annular self-expanding THV and 95 with a balloon-expandable THV. The baseline characteristics of the overall cohort are shown in Table S1. There were differences between the self-expanding THV and balloon-expandable THV groups in terms of male sex (67.5% vs. 48.4%, P=0.04), mean gradient (26.9±16.1 vs. 36.4±15.7 mmHg, P=0.002), mode of bioprosthesis failure (stenosis vs. regurgitation vs. combined, P=0.051), stentless bioprosthesis (32.5% vs. 10.5%, P=0.002), and early-generation THV (35.0% vs. 56.8%, P=0.02).

After performing propensity score matching, 37 patients receiving self-expanding THV were matched with 37 patients receiving balloon-expandable THV. The baseline characteristics of the propensity score-matched cohort are shown in Table 1. Both groups were well matched with no significant differences in comorbidities, preoperative hemodynamic data, surgical valve characteristics, and procedural characteristics.

Table 1. Baseline and Procedural Details of Propensity Score-Matched Cohort of VIV TAVR Patients

	Propensity score-matched cohort
	Self-expanding THV (n=37)	Balloon-expandable THV (n=37)	P value
Demographic and clinical characteristics
Age, years	76.8±12.8	76.6±12.3	0.94
Male sex	25 (67.6)	26 (70.3)	>0.99
BSA, m2	1.85±0.22	1.89±0.26	0.54
NYHA class III or IV	35 (94.6)	36 (97.3)	>0.99
Prior PCI	7 (18.9)	7 (18.9)	1.00
Prior CABG	13 (35.1)	10 (27.0)	0.61
Prior cerebrovascular disease	4 (10.8)	3 (8.1)	>0.99
Diabetes mellitus	3 (8.1)	4 (10.8)	>0.99
Hypertension	33 (89.2)	31 (83.8)	0.73
COPD	5 (13.5)	6 (16.2)	>0.99
Renal insufficiency*	26 (70.3)	28 (75.7)	0.77
Previous pacemaker	8 (21.6)	10 (27.0)	0.77
STS score, %	4.6 (2.6–6.7)	3.9 (2.2–7.8)	0.97
Echocardiographic data
LVEF, %	50.9±17.0	50.0±12.8	0.78
Aortic valve area, cm2	0.9 (0.6–1.0)	0.8 (0.6–1.2)	0.75
Mean gradient, mmHg	27.8±16.3	28.7±13.5	0.73
Surgical valve characteristics
Time since last SAVR, years	11 (6–14)	11 (6–16)	0.70
Mode of bioprosthesis failure			0.82
Stenosis	16 (43.2)	16 (43.2)
Regurgitation	14 (37.8)	12 (32.4)
Combined	7 (18.9)	9 (24.3)
Bioprosthesis label size (mm)			0.64
≤21	13 (35.1)	10 (27.0)
>21 and <25	8 (21.6)	7 (18.9)
≥25	16 (43.2)	20 (54.1)
Surgical valve true ID (mm)			0.89
<20	15 (40.5)	14 (37.8)
≥20 and <23	6 (16.2)	5 (13.5)
≥23	16 (43.2)	18 (48.6)
Stentless bioprosthesis	10 (27.0)	8 (21.6)	0.73
Procedural characteristics
Transfemoral access	36 (97.3)	37 (100)	>0.99
Early-generation THV	13 (35.1)	13 (35.1)	1.00
New-generation THV	24 (64.9)	24 (64.9)
THV size (mm)			NA
20	0 (0)	4 (10.8)
23	18 (48.6)	15 (40.5)
26	11 (29.7)	10 (27.0)
29	6 (16.2)	8 (21.6)
31	2 (5.4)	0 (0.0)

Values are expressed as total number (percentage), mean±standard deviation, or median (interquartile range). *Estimated glomerular filtration rate <60 mL/min/1.73 m². BSA, body surface area; CABG, coronary artery bypass grafting; COPD, chronic obstructive pulmonary disease; ID, internal diameter; LVEF, left ventricular ejection fraction; NYHA, New York Heart Association; PCI, percutaneous coronary intervention; SAVR, surgical aortic valve replacement; TAVR, transcatheter aortic valve replacement; STS, Society of Thoracic Surgeons; THV, transcatheter heart valves; VIV, valve-in-valve.

Hemodynamic and Procedural Outcomes

Hemodynamic and procedural outcomes are summarized in Table 2. Postprocedural hemodynamics showed a significantly lower mean gradient (12.1±6.1 vs. 19.0±7.3 mmHg, P<0.001) (Figure 1) and larger effective orifice area (EOA) (1.50±0.63 vs. 1.13±0.32 cm², P=0.02) in the self-expanding group than in the balloon-expandable THV group. High postprocedural gradients (≥20 mmHg) were more common in the balloon-expandable THV group than in the self-expanding THV group (43.2% vs. 10.8%, P=0.008). No patients had severe AR in either group. The incidence of at least mild-degree AR was similar in the 2 groups (21.6% vs. 10.8%, P=0.39) (Figure 2). There was no significant difference between groups in terms of procedural outcomes, including coronary obstruction, need for a second THV, and new permanent pacemaker implantation.

Table 2. Procedural, Hemodynamic, and Clinical Outcomes of VIV TAVR

	Self-expanding THV (n=37)	Balloon-expandable THV (n=37)	P value
Procedural outcomes
Post-dilatation, n	11 (29.7)	5 (13.5)	0.15
Coronary obstruction, n	0 (0)	2 (5.4)	0.50
Second valve required, n	2 (5.4)	1 (2.7)	>0.99
New permanent pacemaker, n	4 (10.8)	2 (5.4)	0.63
Post-implantation echocardiographic data
Mean gradient, mmHg	12.1±6.1	19.0±7.3	<0.001
Mean gradient ≥20 mmHg	4 (10.8)	16 (43.2)	0.008
Effective orifice area, cm2	1.50±0.63	1.13±0.32	0.02
Effective orifice area index, cm2/m2	0.83±0.36	0.62±0.19	0.02
LVEF, %	51.1±16.6	52.7±17.2	0.67
AR of at least mild degree	8 (21.6)	4 (10.8)	0.39
30-day outcomes
Death	0 (0.0)	1 (2.7)	>0.99
Stroke	1 (2.7)	1 (2.7)	1.00
Major vascular complication	1 (2.7)	1 (2.7)	1.00
Major/life-threatening bleeding	1 (2.7)	2 (5.4)	>0.99
Acute kidney injury	1 (2.7)	2 (5.4)	>0.99

Values are expressed as total number (percentage), mean±standard deviation, or median (interquartile range). AR, aortic regurgitation. Other abbreviations as in Table 1.

Figure 1.

Postprocedural mean gradient after VIV replacement with self-expanding THV and balloon-expandable THV. THV, transcatheter heart valve; VIV, valve-in-valve.

Figure 2.

Aortic regurgitation after VIV replacement with self-expanding THV and balloon-expandable THV. THV, transcatheter heart valve; VIV, valve-in-valve.

For the analysis of THV implantation depth, 12 cases in the self-expanding THV group and 10 cases in the balloon-expandable THV group were excluded because of unreliable information about the implantation depth or inadequate quality of the angiographic images. The rate of high implantation was comparable between patients in the self-expanding THV and balloon-expandable THV groups (16.0% vs. 11.1%, P=0.61).

In terms of 30-day clinical outcomes, there were no significant differences between groups in 30-day all-cause death, stroke, major vascular complications, major/life-threatening bleeding, and acute kidney injury.

At 1-year follow-up, hemodynamic data were available for 16 patients in the self-expanding THV group and 14 patients in the balloon-expandable THV group. The self-expanding THV group had a significantly lower mean transaortic gradient (9.4±5.5 vs. 17.2±7.1 mmHg, P=0.03) than the balloon-expandable THV group and showed a trend towards larger EOA (1.56±0.22 vs. 1.26±0.34 cm², P=0.08).

Outcomes According to the Generation of THV

In both the self-expanding and balloon-expandable THV groups, 13 and 24 patients were treated with early- and new-generation THV, respectively. In the self-expanding THV group, significantly lower postprocedural gradients were consistently observed for both the early-generation THV (12.3±6.0 vs. 22.0±9.4 mmHg, P=0.004) and the new-generation THV (12.0±6.3 vs. 17.4±5.6 mmHg, P=0.003) (Figure 3). In the self-expanding THV group, the new-generation THV showed a trend towards a lower incidence of at least mild AR than the early-generation THV (12.5% vs. 38.5%, P=0.07). A similar trend was observed in the balloon-expandable THV group (4.2% vs. 23.1%, P=0.08) (Figure 4).

Figure 3.

Postprocedural mean gradient after VIV replacement with self-expanding THV and balloon-expandable THV stratified according to the generation of THV. THV, transcatheter heart valve; VIV, valve-in-valve.

Figure 4.

Aortic regurgitation after VIV replacement with self-expanding THV and balloon-expandable THV stratified according to the generation of THV. THV, transcatheter heart valve; VIV, valve-in-valve.

Midterm Mortality

The median follow-up period for this cohort was 202 days (IQR: 37–440 days). A total of 8 patients died during follow-up (2 in the self-expanding THV group, 6 in the balloon-expandable THV group). There were no differences in the cumulative 2-year mortality between groups (22.4% vs. 43.4%, log-rank P=0.26) (Figure 5).

Figure 5.

Kaplan-Meier curves for death after VIV replacement according to use of self-expanding or balloon-expandable THV. THV, transcatheter heart valve; VIV, valve-in-valve.

Postprocedural Gradient

In the overall cohort (n=135), high postprocedural gradients (mean gradient ≥20 mmHg) were recorded in 48 patients (35.6%). In the multivariable model, the independent predictors of high postprocedural gradient were balloon-expandable THV (odds ratio [OR]: 8.24; 95% confidence interval [CI]: 2.44–27.8; P=0.001) and small surgical valve (true ID <20 mm) (OR: 5.28; 95% CI: 2.18–12.8; P<0.001) (Table S2).

CT Evaluation of Subclinical Leaflet Thrombosis After TAVR

In the overall cohort, 61 patients (45.2%) underwent CT scan after TAVR. The median time from TAVR to CT scanning was 38 days (IQR: 33–311 days). Of these patients, 47 (13 in self-expanding group, 34 in balloon-expandable THV group) had interpretable CT scans. Reduced leaflet motion was detected in 11 patients (1 in the self-expanding group, 10 in the balloon-expandable THV group). The incidence of reduced leaflet motion was numerically lower in the self-expanding THV group, although it did not reach statistical significance (7.7% vs. 29.4%, P=0.12).

Discussion

To the best of our knowledge, this is the first comparison of the hemodynamic and clinical outcomes of supra-annular self-expandable and balloon-expandable THV for VIV implantation in a propensity score-matched population, accounting for the generation (early or new) of THV.

The main findings of the present study were as follows. (1) In the propensity score-matched cohorts, supra-annular self-expandable THV were associated with a lower postprocedural mean gradient. This difference was observed consistently among patients treated with the early- or new-generation THV and was maintained at 1-year follow-up. (2) The incidence of postprocedural AR of at least mild degree was comparable between the self-expanding and balloon-expandable THV groups. In both THV groups, there was a trend towards a lower incidence of postprocedural AR of at least mild degree with new-generation THV compared with early-generation THV. (3) The cumulative 2-year mortality rate was comparable between the self-expanding and balloon-expandable THV groups.

The differences in the postprocedural gradient between the self-expanding THV and balloon-expandable THV are likely attributable to the supra-annular design, not to the expansion system itself. The functioning part of the self-expanding THV used in this study was in the supra-annular position, whereas that of the balloon-expandable THV was intra-annular. A previous study using an in vitro model revealed the superior hemodynamic results of supra-annular valves in VIV.^14,15 Moreover, another study showed that higher implantation of THV was associated with lower postprocedural gradients.¹⁰ The results of an observational study that showed lower postprocedural gradients in supra-annular self-expanding THV than in intra-annular self-expanding THV further support this hypothesis.¹⁶

The present study did not show a significant association between THV type and death; however, our cohort may have been underpowered for such an analysis. Although the relationship between high postprocedural gradient and poor clinical outcome has not been conclusively established,¹⁷ a large observational study demonstrated that patients with high postprocedural gradients had higher mortality rates,³ which suggests that the improved hemodynamic outcomes with the supra-annular self-expanding THV are also beneficial in terms of death. Future studies involving a larger sample population and longer-term follow-up are warranted to validate this association.

In addition, a high postoperative gradient may lead to structural valve deterioration (SVD) after TAVR, based on recent data demonstrating that prosthesis-patient mismatch accelerates the SVD of bioprostheses after SAVR.¹⁸ An in vitro study also indicated that incomplete expansion of the THV induces mechanical stress in the leaflets, which may lead to premature SVD.¹⁹ This is a very important concern when considering VIV TAVR for a younger and lower-risk population.

For patients with small bioprosthetic valves, some investigators have reported the usefulness of intentional fracture of the valve with an ultra-high-pressure oversized balloon in order to prevent high residual gradients after VIV.^20,21 Surgical bioprosthetic valves with expansible stents are currently being developed by manufacturers to facilitate the effective and safe performance of the procedure. The combination of intentional fracture of such surgical valves and the use of supra-annular THV may optimize the outcomes of the VIV procedure in the future.

In the present study, new-generation THV were associated with a lower incidence of postprocedural AR, consistent with previous studies involving TAVR for native AS.^22,23 Although there are no data regarding the effect of postprocedural AR on the death of patients undergoing the VIV procedure, given that mild or moderate/severe paravalvular regurgitation is associated with higher mortality rates after TAVR for native AS,^24,25 the result may also be considered beneficial in VIV TAVR.

High postprocedural gradients after VIV warrant attention, particularly in a younger population for whom durability and longevity are paramount. In such patients, the use of supra-annular self-expanding THV may be preferable.

Study Limitations

First, this study had the inherit limitations of an observational study. Although the current analysis included propensity score matching, the presence of residual confounding factors cannot be excluded. Second, our study was conducted in a cohort comprising a relatively small number of patients; therefore, it may have been underpowered to detect certain differences between the patient groups. Further studies involving larger sample population are required to confirm these results. Finally, although the echocardiographic and angiographic parameters were evaluated by experienced cardiologists, there was no centralized core laboratory.

Conclusions

The present study found that the use of supra-annular self-expanding THV was associated with a lower postprocedural gradient in patients undergoing aortic VIV replacement in a propensity score-matched cohort. This difference was observed consistently among patients treated with either an early- or new-generation THV.

Acknowledgments

None.

Sources of Funding

This work was supported by Cedars-Sinai Heart Institute.

Conflicts of Interest

R.M. has received grant support from Edwards Lifesciences Corporation, is a consultant for Abbott Vascular, Cordis, and Medtronic, and holds equity in Entourage Medical. R.S. is a consultant for Edwards Lifesciences Corporation, Abbott Vascular, Keystone Heart, and Boston Scientific. All other authors have no conflicts of interest to disclose.

Supplementary Files

Supplementary File 1

Table S1. Baseline and procedural details of overall cohort

Table S2. Predictors of high postprocedural gradient after VIV replacement

Please find supplementary file(s);

http://dx.doi.org/10.1253/circj.CJ-18-0157

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