Transcatheter Valve Replacement in Asia Pacific: Current Practice and Perspectives

Unbiased proteomic analysis of extracellular vesicles secreted by senescent human vascular smooth muscle cells reveals their ability to modulate immune cell functions

Atherosclerosis, a common age-related disease, is characterized by intense immunological activity. Atherosclerotic plaque is composed of endothelial cells, vascular smooth muscle cells (VSMCs), lipids and immune cells infiltrating from the blood. During progression of the disease, VSMCs undergo senescence within the plaque and secrete SASP (senescence-associated secretory phenotype) factors that can actively modulate plaque microenvironment. We demonstrated that senescent VSMCs secrete increased number of extracellular vesicles (senEVs). Based on unbiased proteomic analysis of VMSC-derived EVs and of the soluble fraction of SASP (sSASP), more than 900 proteins were identified in each of SASP compartments. Comparison of the composition of VMSC-derived EVs with the SASP atlas revealed several proteins, including Serpin Family F Member 1 (SERPINF1) and Thrombospondin 1 (THBS1), as commonly upregulated components of EVs secreted by senescent VSMCs and fibroblasts. Among soluble SASP factors, only Growth Differentiation Factor 15 (GDF15) was universally increased in the secretome of senescent VSMCs, fibroblasts, and epithelial cells. Bioinformatics analysis of EV proteins distinguished functionally organized protein networks involved in immune cell function regulation. Accordingly, EVs released by senescent VSMCs induced secretion of IL-17, INFγ, and IL-10 by T cells and of TNFα produced by monocytes. Moreover senEVs influenced differentiation of monocytes favoring mix M1/M2 polarization with proinflammatory characteristics. Altogether, our studies provide a complex, unbiased analysis of VSMC SASP and prove that EVs derived from senescent VSMCs influence the cytokine milieu by modulating immune cell activity. Our results strengthen the role of senescent cells as an important inducer of inflammation in atherosclerosis.

Quantitative Angiographic Assessment of Aortic Regurgitation Following 11 TAVR Devices: An Update of a Multicenter Pooled Analysis

Background

Aortic regurgitation (AR) following transcatheter aortic valve replacement (TAVR) is a major predictor of short- and long-term survival. Thus far, no independent quantitative comparison of AR among commercially available transcatheter heart valves (THVs) has been performed.

Objectives

We sought to assess and compare the degree of acute AR following TAVR between 11 commercially available THVs and update our previous multicenter, pooled analysis.

Methods

Analyses were performed by an independent academic core lab using quantitative videodensitometry, a technique relying solely on the aortogram acquired after TAVR. The pooled analysis (n = 2665) included data from the initial cohort of 7 valves (Lotus [n = 546], Evolut PRO [n = 95], SAPIEN 3 [n = 397], Evolut R [n = 295], SAPIEN XT [n = 239], ACURATE neo [n = 120], and CoreValve [n = 532]) to which data from 4 new valves were added (ACURATE neo2 [n = 120], Myval [n = 108], VitaFlow [n = 105], and Venus-A [n = 113]).

Results

The Lotus valve had the lowest mean AR (3.5% ± 4.4%) followed by ACURATE neo2 (4.4% ± 4.8%), VitaFlow (6.1% ± 6.4%), Myval (6.3% ​± ​6.3%), Evolut PRO (7.4% ± 6.5%), SAPIEN 3 (7.6% ± 7.1%), Evolut R (7.9% ± 7.4%), SAPIEN XT (8.8% ± 7.5%), Venus-A (8.9% ​± ​10%), ACURATE neo (9.6% ± 9.2%), and CoreValve (13.7% ± 10.7%, analysis of variance P-value < .001). The only valves that statistically differed from all their counterparts were Lotus, with the lowest regurgitation in comparison to other valves except ACURATE neo2, which had less regurgitation compared with SAPIEN 3, Evolut R, SAPIEN XT, Venus-A, ACURATE neo, and CoreValve. CoreValve had the highest mean of AR, with the rates of moderate/severe AR: ACURATE neo2 (1.7%), Lotus (2.2%), Myval (2.8%), VitaFlow (4.7%), Evolut PRO (5.3%), SAPIEN 3 (8.3%), Evolut R (8.8%), SAPIEN XT (10.9%), ACURATE neo (11.3%), Venus-A (14.2%), and CoreValve (30.1%)-χ2 P-value < .001.

Conclusions

In this updated pooled analysis, the Lotus valve had the lowest mean AR, while ACURATE neo2 had the lowest rate of moderate/severe AR. Myval, VitaFlow, and Venus-A THVs showed promising results.

Racial Differences in the Incidence and Impact of Prosthesis-Patient Mismatch After Transcatheter Aortic Valve Replacement

OBJECTIVES

The aim of this study was to compare the incidence and prognostic significance of prosthesis-patient mismatch (PPM) after transcatheter aortic valve replacement (TAVR) according to racial groups.

BACKGROUND

PPM after TAVR may be of more concern in Asian populations considering their relatively small annular and valve sizes compared with Western populations.

METHODS

TP-TAVR (Transpacific TAVR Registry) was an international multicenter cohort study of patients with severe aortic stenosis who underwent TAVR in the United States and South Korea from January 2015 to November 2019. PPM was defined as moderate (0.65-0.85 cm²/m²) or severe (<0.65 cm²/m²) at the indexed effective orifice area. The primary outcome was a composite of death, stroke, or rehospitalization at 1 year.

RESULTS

Among 1,101 eligible patients (533 Asian and 569 non-Asian), the incidence of PPM was significantly lower in the Asian population (33.6%; moderate, 26.5%; severe, 7.1%) than in the non-Asian population (54.5%; moderate, 29.8%; severe, 24.7%). The 1-year rate of the primary outcome was similar between the PPM and non-PPM groups (27.5% vs 28.1%; P = 0.69); this pattern was consistent between Asian (25.4% vs 25.2%; P = 0.31) and non-Asian (28.7% vs 32.1%; P = 0.97) patients. After multivariable adjustment, the risk for the primary outcome did not significantly differ between the PPM and non-PPM groups in the overall population (HR: 0.95; 95% CI: 0.74-1.21), in Asian patients (HR: 1.07; 95% CI: 0.74-1.55), and in non-Asian patients (HR: 0.86; 95% CI: 0.63-1.19).

CONCLUSIONS

In this study of patients with severe aortic stenosis who underwent TAVR, the incidence of PPM was significantly lower in Asian patients than in non-Asian patients. The 1-year risk for the primary composite outcome was similar between the PPM and non-PPM groups regardless of racial group. (Transpacific TAVR Registry [TP-TAVR]; NCT03826264).

Transcatheter Aortic Valve Replacement in Asia: Present Status and Future Perspectives

Over the last decade, based on evidence from multiple randomized clinical trials, transcatheter aortic valve replacement (TAVR) has become the established treatment for patients with symptomatic severe aortic stenosis. Despite the overwhelming expansion of TAVR in Western countries, the initial uptake and widespread adoption of this procedure have been relatively delayed in Asian countries, owing to the high cost of devices; limited local health and reimbursement policies; and lack of specific training/proctoring program, specialized heart team, or dedicated infrastructure. Furthermore, it has not yet been determined whether there are substantial interracial and ethnic differences in the clinical characteristics, comorbidities, and anatomic features, as well as procedural and long-term outcomes, in patients receiving TAVR. In this review, we provide not only a comprehensive look at the current status and outcomes of TAVR in Asian populations compared with those of Western populations but also a perspective on the future of TAVR in Asia.

Inter-Ethnic Differences in Valvular Dysfunction, Aortopathy, and Progression of Disease of an Asian Bicuspid Aortic Valve Population

BACKGROUND

There are differences in bicuspid aortic valve (BAV) characteristics between Asian and European populations, but little is known about the inter-ethnic differences in bicuspid valve function and aortic root dimensions within the diverse Asian population.

METHODS

From 1992-2017, 562 patients with index echocardiographic diagnosis of BAV in a tertiary health care institution in Singapore were analysed according to their ethnic groups: Chinese, Malay, Indian, and Eurasian. Study outcomes included BAV complications (infective endocarditis, aortic dissection) and clinical outcomes (aortic valve surgery, aortic root surgery, all-cause mortality). Total events were defined as composite outcome of all BAV complications and outcomes. Aortic dimensions and aortic dilatation rates were also studied.

RESULTS

There were 379 (67.5%) Chinese, 79 (14.0%) Malay, 73 (13.0%) Indian, and 31 (5.5%) Eurasian patients. Type 1 BAV (58.5%) was the most prevalent BAV morphology, with moderate-to-severe aortic stenosis (AS) (36.8%) being the most common complication in the overall population. There was a higher prevalence of type 0 BAV in Chinese and Indian groups, and type 1 BAV with fusion of left-right coronary cusp in Eurasian and Malay groups (p=0.082). There was no difference in significant AS among groups. The highest prevalence of moderate-to-severe aortic regurgitation was observed amongst the Eurasian group, followed by Chinese, Indian, and Malay groups (p=0.033). The Chinese group had the largest mean indexed diameters of the aortic root. Multivariable linear regression demonstrated that only the Chinese had significantly larger indexed diameters in the aortic annulus, sinotubular junction (STJ), and ascending aorta (AA), relative to the Eurasian group, after adjusting for age, sex, smoking, hypertension, hyperlipidaemia, diabetes, and aortic regurgitation. On follow-up echocardiography, there was a trend towards the highest dilatation rates of sinus of Valsalva and STJ amongst Indian, and AA amongst Malay groups. Kaplan-Meier curves showed the highest incidence of total events amongst Chinese, followed by Malay, Indian and Eurasian (log-rank=9.691; p=0.021) patients.

CONCLUSION

There were differences in BAV morphology, valve dysfunction, aortopathy, and prognosis within the Asian population. Chinese patients had one of the highest prevalence of significant aortic regurgitation, with the largest aortic dimensions and worst outcomes compared with other Asian ethnicities. Closer surveillance is warranted in BAV patients within the Asian population.

A single-center analysis of outcomes, risk factors, and new valves in Asian patients treated with early transcatheter aortic valve implantation

Background

Transcatheter aortic valve implantation (TAVI) continues to expand as an optimal treatment in Western countries; however, Asian countries have been slower to adopt this procedure. This research aimed to explore the outcomes and status of early TAVI performed at a single center in Asia, and provide comparative outcomes of the newly designed Chinese valves.

Methods

We enrolled 175 consecutive patients who successfully underwent TAVI from September 2012 to January 2018 at Fuwai Hospital (Beijing, China). After a preliminary assessment of age, we included 109 older patients (≥69 years) who underwent surgical aortic valve replacement (SAVR) during the same period. The primary endpoint was all-cause mortality. The inverse probability of treatment weighting (IPTW) was used to reduce potential bias. Cox regression was used to identify the risk factors of a poor prognosis.

Results

The TAVI cohort had higher rates of all-cause mortality [11.4% vs. 2.4%, hazard ratio (HR): 4.79, 95% confidence interval (CI): 1.47 to 15.57, IPTW-adjusted P=0.009] and permanent pacemaker implantation (PPI; 14.6% vs. 1.6%, HR: 9.98, 95% CI: 2.71 to 36.67, IPTW-adjusted P<0.001) at 3 years than the SAVR cohort. In the multivariable Cox regression analysis based on the entire sample, liver disease was associated with all-cause mortality (HR: 5.080, 95% CI: 1.067 to 24.174, P=0.041). A smoking history was associated with an increased risk of postoperative heart failure (HF) (HR: 4.902, 95% CI: 1.265 to 18.999, P=0.022). Additionally, age (HR: 1.141, 95% CI: 1.010 to 1.288, P=0.034) and diabetes (HR: 7.301, 95% CI: 2.414 to 22.079, P<0.001) were identified as predictors of postoperative stroke. In the new valve subgroups, the 1-year composite endpoints were 38.2% (Venus A), 35.3% (TaurusOne), 34% (J-Valve), and 28% (VitaFlow) (P=0.857).

Conclusions

Not all TAVI procedures had satisfactory outcomes compared with SAVR when initiated. At first, our center faced some challenges in delivering TAVI, and this is probably one of the reasons why the use of TAVI has developed slowly in Asia. Further investigations are needed to explore the underlying factors precluding the rapid expansion of TAVI in Asia.

Balloon Versus Self-Expandable Valve for the Treatment of Bicuspid Aortic Valve Stenosis: Insights From the BEAT International Collaborative Registrys

BACKGROUND

Large data comparing the performance of new-generation self-expandable versus balloon-expandable transcatheter heart valves in bicuspid aortic stenosis are lacking. We aim to compare the safety and performance of balloon-expandable and self-expandable transcatheter heart valves in the treatment of bicuspid aortic stenosis.

METHODS

The BEAT (balloon versus self-expandable valve for the treatment of bicuspid aortic valve stenosis) registry included 353 consecutive patients who underwent transcatheter aortic valve implantation using new-generation Evolut R/PRO or Sapien 3 valves in bicuspid aortic valve.

RESULTS

A total of 353 patients (n=242 [68.6%] treated with Sapien 3 and n=111 [68.6%] treated with Evolut R (n=70)/PRO [n=41]) were included. Mean age was 77.8±8.3 years and mean Society of Thoracic Surgeons Predicted Risk of Mortality was 4.4±3.3%. Valve Academic Research Consortium-2 device success was similar between Sapien 3 and Evolut R/PRO (85.6% versus 87.2%; P=0.68). In the Sapien 3 group, 4 patients experienced annular rupture whereas this complication did not occur in the Evolut R/PRO group. After propensity score matching, Valve Academic Research Consortium-2 device success was similar between both groups (Sapien 3=85.7% versus Evolut R/Pro=84.4%; P=0.821). Both in the overall and in the matched population, no differences in the rate of permanent pacemaker implant were observed. At 1-year follow-up, the rate of overall death and cardiovascular death were similar between the 2 groups. In the unmatched population, the 1-year echocardiographic follow-up demonstrated similar rate of moderate-to-severe paravalvular aortic regurgitation (Evolut R/PRO 10.5% versus Sapien 3 4.2%, P=0.077); however, after propensity matching, the rate of moderate-to-severe paravalvular leak became significantly higher among patients treated with self-expandable valves (9.3% versus 0%; P=0.043).

CONCLUSIONS

Our study confirms the feasibility of both Sapien 3 and Evolut R/PRO implantation in bicuspid aortic valve anatomy; a higher rate of moderate-severe paravalvular aortic regurgitation was observed in the Evolut R/PRO group at 1-year follow-up in the matched cohort, although patients treated with balloon-expandable valve had a higher rate of annular rupture.

Transcatheter aortic valve implantation after previous mechanical mitral valve replacement in a patient with coexistent rheumatic aortic stenosis and regurgitation

A 67-year-old female was referred to our center with rheumatic aortic stenosis (AS) and aortic regurgitation (AI). As the patient was a high-risk case for surgery, we chose transcatheter aortic valve implantation (TAVI) as the treatment of choice. However, the thickened, long, and mildly calcified aortic valve, and the very small distance (7 mm) between the aortic annulus and mechanical mitral valve (MMV) increased the risk of coronary artery occlusion and flap clamping of MMV. As the left ventricle was small in size, transfemoral TAVI, which causes lesser degree of trauma to the patient, was successfully performed eventually.

Aortic roots assessment by an automated three-dimensional transesophageal echocardiography: an intra-individual comparison

To evaluate the accuracy, reproducibility, and transcatheter heart valve (THV) sizing efficiency of an automated 3-dimensional transesophageal echocardiographic (3D-TEE) post-processing software in the assessments of aortic roots, intra-individually compared with multidetector computed tomography (MDCT). We prospectively studied 67 patients with normal aortic roots. We measured diameters of aortic annulus (AA), sinus of Valsalva (SOV), and sino-tubular junction (STJ) by full-automated and semi-automated methods using 3D-TEE datasets, then compared them to corresponding transthoracic echocardiography and MDCT values. THV sizes were chosen based on echocardiography and MDCT measurements according to recommended criterion. Taking MDCT planimetered diameters as reference, the full-automated (r: 0.4745-0.8792) and semi-automated (r: 0.6647-0.8805) 3D-TEE measurements were linearly correlated (p < 0.0001). The average differences between semi-automated or full-automated measurements and reference were 0.3 mm or 1.3 mm for AA, - 1.9 mm or - 0.5 mm for SOV, and - 0.1 mm or 1.9 mm for STJ, respectively. The intra-class correlation coefficients of semi-automated method were 0.79-0.96 (intra-observer) and 0.75-0.92 (inter-observer). THV sizing by semi-automated measurements using echocardiographic criteria was larger than that by MDCT measurements using MDCT criteria (p < 0.0001) but equivalent (p > 0.05) if both using MDCT standards. The new automated 3D-TEE software allows modeling and quantifying aortic roots with high reproducibility. Measurements by the semi-automated method closely approximate and well correlate with the corresponding MDCT, thus THV sizing by this modeled 3D-TEE measurements should adopt recommended MDCT criteria but not echocardiographic criteria. The full-automated 3D-TEE segmentations are yet immature. (Semi-automated assessMent of Aortic Roots by Three-dimensional transEsophageal echocaRdiography [SMARTER], NCT02724709).