Transcatheter aortic valve replacement for aortic regurgitation: a systematic review and meta-analysis.

The efficacy and safety of new-generation devices (NGDs) for severe aortic regurgitation (AR) have mostly been based on single-arm studies with limited sample sizes. Our goal was to summarize the current evidence on NGDs and compare the safety and efficacy of 'off-label' and 'on-label' devices in NGDs. We searched MEDLINE, Embase, Cochrane Library, and Scopus for articles on transcatheter aortic valve replacement in patients with AR. A total of 31 studies that included 1851 patients were identified through April 2023. Among these, 1067 (57.6%) patients received treatment with 'on-label' devices (JenaValve and J-Valve). For NGDs, the total device success rate at 30 days was 94.5% (on-label: 97.8%, off-label: 89.9%; P < 0.001), the all-cause mortality was 4.2% (on-label: 2.6%, off-label: 5.1%; P = 0.006), permanent pacemaker implantation (PPI) was 8.8% (on-label: 6.9%, off-label: 18.4%; P < 0.001), and the rate of greater-than-mild paravalvular leak (PVL) was 1.2% (on-label: 0.9%, off-label: 3.8%; P = 0.003). On-label devices showed significantly better safety and efficacy in terms of the success rate, PPI, greater-than-mild PVL, and 30 day mortality than off-label devices.

Safety and efficacy of the DragonFly system for transcatheter valve repair of degenerative mitral regurgitation: one-year results of the DRAGONFLY-DMR trial.

BACKGROUND: Severe degenerative mitral regurgitation (DMR) can cause a poor prognosis if left untreated. For patients considered at prohibitive surgical risk, transcatheter edge-to-edge repair (TEER) has become an accepted alternative therapy. The DragonFly transcatheter valve repair system is an innovative evolution of the mitral TEER device family to treat DMR. AIMS: Herein we report on the DRAGONFLY-DMR trial (ClinicalTrials.gov: NCT04734756), which was a prospective, single-arm, multicentre study on the safety and effectiveness of the DragonFly system. METHODS: A total of 120 eligible patients with prohibitive surgical risk and DMR ≥3+ were screened by a central eligibility committee for enrolment. The study utilised an independent echocardiography core laboratory and clinical event committee. The primary endpoint was the clinical success rate, which measured freedom from all-cause mortality, mitral valve reintervention, and mitral regurgitation (MR) >2+ at 1-year follow-up. RESULTS: At 1 year, the trial successfully achieved its prespecified primary efficacy endpoint, with a clinical success rate of 87.5% (95% confidence interval: 80.1-92.3%). The rates of major adverse events, all-cause mortality, mitral valve reintervention, and heart failure hospitalisation were 9.0%, 5.0%, 0.8%, and 3.4%, respectively. MR ≤2+ was 90.4% at 1 month and 92.0% at 1 year. Over time, left ventricular reverse remodelling was observed (p<0.05), along with significant improvements in the patients' functional and quality-of-life outcomes, shown by an increase in the New York Heart Association Class I/II from 32.4% at baseline to 93.6% at 12 months (p<0.001) and increased Kansas City Cardiomyopathy Questionnaire (KCCQ) score of 31.1±18.2 from baseline to 12 months (p<0.001). CONCLUSIONS: The DRAGONFLY-DMR trial contributes to increasing evidence supporting the safety and efficacy of TEER therapy, specifically the DragonFly system, for treating patients with chronic symptomatic DMR 3+ to 4+ at prohibitive surgical risk.

Percutaneous Coronary Intervention Offers Clinical Benefits to Diabetic Patients With Stable Chronic Total Occlusion.

Whether percutaneous coronary intervention for chronic total occlusion (CTO-PCI) in diabetic patients offers more benefits compared with initial medical therapy (CTO-MT) is unclear. In this study, diabetic patients with one CTO (clinical manifestations: stable angina or silent ischemia) were enrolled. Consecutively, enrolled patients (n = 1605) were assigned to different groups: CTO-PCI (1044 [65.0%]) and initial CTO-MT (561 [35%]). After a median follow-up of 44 months, CTO-PCI tended to be superior to initial CTO-MT in major adverse cardiovascular events (adjusted hazard-ratio [aHR]: .81, 95% conference-interval: .65-1.02) and significantly superior in cardiac death (aHR: .58 [.39-.87]) and all-cause death (aHR: .678[.473-.970]). Such superiority mainly attributed to a successful CTO-PCI. CTO-PCI tended to be performed in patients with younger age, good collaterals, left anterior descending branch CTO, and right coronary artery CTO. While, those with left circumflex CTO and severe clinical/angiographic situations were more likely to be assigned to initial CTO-MT. However, none of these variables influenced the benefits of CTO-PCI. Thus, we concluded that for diabetic patients with stable CTO, CTO-PCI (mainly successful CTO-PCI) offered patients survival benefits over initial CTO-MT. These benefits were consistent regardless of clinical/angiographic characteristics.

Determinants of device success after transcatheter aortic valve replacement in patients with type-0 bicuspid aortic stenosis.

Background: Clinical evidence of transcatheter aortic valve replacement in patients with type-0 bicuspid aortic valve was relatively scarce. Aims: Our goal was to explore determinants of device success after transcatheter aortic valve replacement in patients with type-0 bicuspid aortic valve morphology. Methods: In this retrospective multicenter analysis, we included 59 patients with symptomatic severe aortic stenosis with type-0 bicuspid aortic valve morphology who underwent transcatheter aortic valve replacement. Type-0 bicuspid aortic valve was identified with multidetector computed tomography scans. The technical success rate was 89.8%, and the device success rate was 81.4%. Patients were divided into a device success group and a device failure group according to Valve Academic Research Consortium- 3 criteria. Results: When we compared the two groups, we found that the ellipticity index of the aortic root and the presence of bulky calcifications at the commissure were statistically different (ellipticity index 35.7 ± 1.7 vs. 29.7 ± 1.1, p = 0.018; bulky calcification at the commissure, 54.5% vs. 4.5%, p < 0.001). Further multivariate logistic analysis showed that bulky calcification at the commissure had a negative correlation with device success (odds ratio 0.030, 95% confidence interval 0.003-0.285, p = 0.002). Yet there was no statistical correlation between the ellipticity index and device success (odds ratio 0.818, 95% confidence interval 0.667-1.003, p = 0.053). Conclusions: The presence of bulky calcifications at the commissure is negatively correlated with device success after transcatheter aortic valve replacement in patients with type-0 bicuspid aortic valve.

Single femoral artery access is safe and feasible during transcatheter aortic valve replacement: a propensity score matched analysis.

Background: Transcatheter aortic valve replacement (TAVR) potentially may be significantly simplified by using the single artery access (SA) technique, which does not require a secondary artery access. Nevertheless, the safety and efficacy of this technique remains unclear. Our goal was to determine if single artery access TAVR (without upgrading the sheath size) is a feasible, minimally invasive procedure. Methods: Patients with symptomatic severe aortic stenosis who underwent TAVR via the femoral artery were consecutively enrolled in this study. Eligible individuals were divided into 2 groups: the SA group and the dual artery access (DA) group. The primary end point was device success (defined by the valve academic research consortium 3, VARC 3). A 6-month follow-up and propensity score matching analyses were performed. Results: After propensity score matching analysis, a total of 130 patients were included: 65 in the SA group and 65 in the DA group. The SA procedure achieved similar device success (95.4% vs. 87.7%; P = 0.115) compared with the DA procedure. The SA procedure shortened the operating time (102 min vs. 125 min; P = 0.001) but did not increase the x-ray time or dose. Both a 20 Fr and a 22 Fr sheath (without upgrading the sheath size) could be used for the SA procedure. There was no major vascular complication occurred in both groups. The incidence of minor main vascular and access complications in the SA group was comparable to those of the DA procedure (0.0% vs. 3.1%; P = 0.156). Conclusions: The SA access procedure is a promising minimally invasive TAVR technique with a low incidence of vascular complications and a high incidence of device success. It is safe and possibly applicable in all TAVR procedures.

Short-term study of atrial shunt and improvement of functional mitral regurgitation.

BACKGROUND: This study used an atrial septal shunt to compare the treatment progress and prognosis for patients with heart failure (HF) who have different ejection fractions. METHODS: Twenty HF patients with pulmonary hypertension, who required atrial septal shunt therapy, were included in this study. The patients underwent surgery between December 2012 and December 2020. They were divided into two groups based on their ejection fraction: a group with reduced ejection fraction (HFrEF) and a group with preserved ejection fraction(HFpEF) + mid-range ejection fraction (HfmrEF). Echocardiography was utilized to evaluate parameters such as left ventricular dimension (LVD), left ventricular ejection fraction (LVEF), and left ventricular end-diastolic volume (LVEDV). Hemodynamic parameters were measured using cardiac catheterization. The patient's cardiac function was assessed using the six-minute walking test (6MWT), KCCQ score, NYHA classification, and the degree of functional mitral regurgitation (FMR). Followed-up visits were conducted at 1, 3, and 6 months, and any adverse effects were recorded. RESULTS: The LVEF values were consistently higher in the HFpEF+HFmrEF group than HFrEF group at all periods (P < 0.05). Differences in LVD were observed between the two groups before the surgery. Statistically, significant differences were found at the preoperative stage, 1 month, and 3 months (P < 0.05, respectively). However, the LVEDV showed a significant difference between the two groups only at 3 months (P = 0.049). Notably, there were notable variations in LAPm, LAPs, and the pressure gradient between the LA-RA gradient at baeline, after implantation, and during the 6 months follow-up (all P < 0.05). CONCLUSION: Following treatment, the HFpEF+HFmrEF group exhibited more significant improvements in echocardiographic and cardiac catheterization indices than the HFrEF group. However, there was no statistically significant difference between the two groups regarding the 6MWT and KCCQ scores. It is important to note that the findings of this study still require further investigation in a large sample size of patients.

A single amino acid substitution in the capsid protein of Zika virus contributes to a neurovirulent phenotype.

Increasing evidence shows the African lineage Zika virus (ZIKV) displays a more severe neurovirulence compared to the Asian ZIKV. However, viral determinants and the underlying mechanisms of enhanced virulence phenotype remain largely unknown. Herein, we identify a panel of amino acid substitutions that are unique to the African lineage of ZIKVs compared to the Asian lineage by phylogenetic analysis and sequence alignment. We then utilize reverse genetic technology to generate recombinant ZIKVs incorporating these lineage-specific substitutions based on an infectious cDNA clone of Asian ZIKV. Through in vitro characterization, we discover a mutant virus with a lysine to arginine substitution at position 101 of capsid (C) protein (termed K101R) displays a larger plaque phenotype, and replicates more efficiently in various cell lines. Moreover, K101R replicates more efficiently in mouse brains and induces stronger inflammatory responses than the wild type (WT) virus in neonatal mice. Finally, a combined analysis reveals the K101R substitution promotes the production of mature C protein without affecting its binding to viral RNA. Our study identifies the role of K101R substitution in the C protein in contributing to the enhanced virulent phenotype of the African lineage ZIKV, which expands our understanding of the complexity of ZIKV proteins.

Computed tomography anatomical characteristics based on transcatheter aortic valve replacement in aortic regurgitation.

This study analyzed computed tomography (CT) measurement characteristics and anatomical classifications based on transcatheter aortic valve replacement (TAVR) in patients with aortic regurgitation (AR) to establish a preliminary summary of CT anatomical characteristics and to design a novel self-expanding transcatheter heart valve (THV). This single-center retrospective cohort study included 136 patients diagnosed with moderate-to-severe AR at Fuwai Hospital from July 2017 to April 2022. Patients were classified into four anatomical classifications according to dual-anchoring multiplanar measurement of where THV anchoring took place. Types 1-3 were considered candidates for TAVR, whereas type 4 was not. Among 136 patients with AR, there were 117 (86.0%) tricuspid, 14 bicuspid, and five quadricuspid valves. Dual-anchoring multiplanar measurement showed that the annulus was smaller than left ventricular outflow tract (LVOT) at 2, 4, 6, 8, and 10 mm on the annulus. The ascending aorta (AA) 40 mm was wider than AA 30 mm and AA 35 mm, but narrower than AA 45 mm and AA 50 mm. For 10% oversize of the THV, the proportions of the annulus, LVOT, and AA unable to meet the diameter were 22.8%, 37.5%, and 50.0%, respectively, and the proportions of anatomical classification types 1-4 were 32.4%, 5.9%, 30.1%, and 31.6%, respectively. The novel THV could significantly improve the type 1 proportion (88.2%). Existing THVs cannot meet the anatomical characteristics of patients with AR. Conversely, based on anatomical characteristics, the novel THV could theoretically facilitate TAVR.

The first clinical data of the SAPIEN 3 aortic valve in the treatment of aortic stenosis in China.

Background: Data on outcomes following transcatheter aortic valve replacement with SAPIEN 3 in China is limited as it was approved by the National Medical Products since 2020. The present study was designed to collect clinical data on the SAPIEN 3 aortic valve in Chinese patients with bicuspid aortic valve and tricuspid aortic valve stenosis. Methods: We analyzed the patient characteristics, procedural features and procedural outcomes of the first 438 patients (223 for bicuspid aortic valve and 215 tricuspid aortic valve) from 21 provinces in 74 sites treated with the SAPIEN 3 valve system for transcatheter aortic valve replacement between September 2020 and May 2022. Results: Procedural mortality was 0.7%. 5 cases during the operation were converted to surgery. Among 438 cases, permanent pacemaker implantation was performed in a total of 12 cases (2.7%). The patient had severe leaflet calcification of the aortic valve, with moderate and severe calcification reaching 39.7% and 35.2% respectively. The size of the implanted valves was predominantly 26 mm and 23 mm, reaching 42.5% and 39.5% respectively. The incidence of moderate or severe perivalvular leak in the postoperative period was 0.5%, with a predominance of 90/10 and 80/20 valve deployment height. There was a significant difference in the deployment height of the valve between bicuspid aortic valve and tricuspid aortic valve, with the bicuspid aortic valve having a more deployment height of 90/10. Annulus size in bicuspid aortic valve group was significantly larger than tricuspid aortic valve group. Valve sizing for oversized, within size, and undersized were different between bicuspid aortic valve and tricuspid aortic valve. Conclusions: Procedural success rates were high, with similar and good results for bicuspid aortic valve and tricuspid aortic valve, low perivalvular leak for both valve types, and low permanent pacemaker implantation rates for both valve types. Annulus size, valve sizing and coronary artery height were significantly different in the BAV and TAV group.

Differential expression profiles and functional analysis of long non-coding RNAs in calcific aortic valve disease.

AIM: To evaluate the expression profile of long non-coding RNAs (lncRNAs) in calcific aortic valve disease (CAVD) and explore their potential mechanism of action. METHODS: The gene expression profiles (GSE153555, GSE148219, GSE199718) were downloaded from the Gene Expression Omnibus (GEO) database and FastQC was run for quality control checks. After filtering and classifying candidate lncRNAs by differentially expressed genes (DEGs) and weighted co-expression networks (WGCNA) in GSE153555, we predicted the potential cis- or trans-regulatory target genes of differentially expressed lncRNAs (DELs) by using FEELnc and established the competitive endogenous RNA (ceRNA) network by miRanda, more over functional enrichment was analyzed using the ClusterProfiler package in R Bioconductor. The hub cis- or trans-regulatory genes were verified in GSE148219 and GSE199718 respectively. RESULTS: There were 340 up-regulated lncRNAs identified in AS group compared with the control group (|log2Fold Change| ≥ 1.0 and Padj ≤ 0.05), and 460 down-regulated lncRNAs. Based on target gene prediction and co-expression network construction, twelve Long non-coding RNAs (CDKN2B-AS1, AC244453.2, APCDD1L-DT, SLC12A5-AS1, TGFB3, AC243829.4, MIR4435-2HG, FAM225A, BHLHE40-AS1, LINC01614, AL356417.2, LINC01150) were identified as the hub cis- or trans-regulatory genes in the pathogenesis of CAVD which were validated in GSE148219 and GSE19971. Additionally, we found that MIR4435-2HG was the top hub trans-acting lncRNA which also plays a crucial role by ceRNA pattern. CONCLUSION: LncRNAs may play an important role in CAVD and may provide a new perspective on the pathogenesis, diagnosis, and treatment of this disease. Further studies are required to illuminate the underlying mechanisms and provide potential therapeutic targets.

Techniques and outcomes of percutaneous aortic anastomosis leak closure after frozen elephant trunk procedure for aortic dissection.

Background: The aim of our study was to provide a summary of applied percutaneous aortic anastomosis leak (AAL) closure techniques after frozen elephant trunk (FET) procedure for aortic dissection and describe the procedural and mid-term outcomes in a consecutive cohort of patients at our center. Methods: All patients who underwent percutaneous closure of AAL after FET between January 2018 and December 2020 were identified. Three different strategies were employed: (I) the retrograde technique; (II) the true-to-false lumen loop technique; and (III) the antegrade technique. Procedural and short-term results were assessed. Results: A total of 34 AAL closure procedures were performed in 32 patients. The mean age was 44.3±9.1 years, and 87.5% of patients were male. Successful device deployments were achieved in 36 leaks (100%). Immediate residual leaks were mild and moderate in 37.5% and 9.4% of patients, respectively. After a mean follow-up of 47.1±24.6 months, reduction in AAL to mild or less was accomplished in 90.6% of patients. Complete thrombosis and basically complete thrombosis of the FET's segment false lumen were achieved in 75.0% and 15.6% of patients, respectively. The maximal diameter of FET's segment false lumen significantly decreased by 13.6±8.7 mm (from 33.0±9.4 to 19.4±16.2 mm, P<0.001). Conclusions: Percutaneous closure of AAL after FET procedure was associated with false lumen reduction of aortic dissection. The magnitude of benefit was greatest with AAL reduction to a grade of mild or less. Therefore, attempts should be made to reduce AAL as much as possible.

Perioperative renal function change after transcatheter aortic valve replacement: A single-center retrospective study in China.

BACKGROUND: In recent years, the kidney function after Transcatheter Aortic Valve Replacement (TAVR) has gradually become a hot spot that arouse extensive attention.Our study is aimed to evaluate the incidence and predictors of acute kidney recovery (AKR) after TAVR. METHODS: A total of 102 patients undergoing TAVR in Beijing Anzhen Hospital from June 2021 to March 2022 were enrolled in our study. Patients were divided into AKR group (n = 54), unchanged group (n = 40) and acute kidney injury (AKI) group (n = 8) based on the percent change of estimated glomerular filtration rate (eGFR). Univariate analysis was used to compare the differences in general clinical characteristics and other related indicators between the three groups to analyze the risk factors of AKR. RESULTS: The incidence of AKR was 53% (54/102) after TAVR. Multivariate analysis showed that the incidence of age and proportion of severe NYHA class (III or IV) was significantly higher in the AKR group while renal dysfunction (eGFR <60 mL/min/1.73 m2) was lower. Besides, fluid management/volume therapy was significantly different among the three groups. CONCLUSIONS: AKR is a generalizable phenomenon occurring frequently after TAVR. The age, proportion of severe NYHA class and the baseline renal function are independent predictors of AKR events in patients with severe aortic stenosis undergoing TAVR.

Can Measuring the 'Dual Anchors of Aorta' Enhance the Success Rate of TAVR?-A Single-Center Experience.

INTRODUCTION: Chronic severe aortic regurgitation (AR) has a poor long-term prognosis, especially among old-age patients. Considering their advancing age, the surgical approach of aortic valve replacement may not always be the best alternative modality of treatment in such patients. Therefore, this study's primary goal was to provide an initial summary of the medium- and short-term clinical effectiveness of transcatheter aortic valve replacement (TAVR) guided by accurate multi-detector computed tomography (MDCT) measurements in patients with severe and chronic AR, especially in elderly patients. METHODS: The study enrolled retrospectively and prospectively patients diagnosed with severe AR who eventually underwent TAVR procedure from January 2019 to September 2022 at Fuwai cardiovascular Hospital, Beijing. Baseline information, MDCT measurements, anatomical classification, perioperative, and 1-year follow-up outcomes were collected and analyzed. Based on a novel anatomical categorization and dual anchoring theory, patients were divided into four categories according to the level of anchoring area. Type 1, 2, and 3 patients (with at least two anchoring regions) will receive TAVR with a transcatheter heart valve (THV), but Type 4 patients (with zero or one anchoring location) will be deemed unsuitable for TAVR and will instead receive medical care (retrospectively enrolled patients who already underwent TAVR are an exception). RESULTS: The mean age of the 37 patients with severe chronic AR was 73.1 ± 8.7 years, and 23 patients (62.2%) were male. The American Association of Thoracic Surgeons' score was 8.6 ± 2.1%. The MDCT anatomical classification included 17 cases of type 1 (45.9%), 3 cases of type 2 (8.1%), 13 cases of type 3 (35.1%), and 4 cases of Type 4 (10.8%). The VitaFlow valve (MicroPort, Shanghai, China) was implanted in 19 patients (51.3%), while the Venus A valve (Venus MedTech, Hangzhou, China) was implanted in 18 patients (48.6%). Immediate TAVR procedural and device success rates were 86.5% and 67.6%, respectively, while eight cases (21.6%) required THV-in-THV implantation, and nine cases (24.3%) required permanent pacemaker implantation. Univariate regression analysis revealed that the major factors affecting TAVR device failure were sinotubular junction diameter, THV type, and MDCT anatomical classification (p < 0.05). Compared with the baseline, the left ventricular ejection fraction gradually increased, while the left ventricular end-diastolic diameter remained small, and the N-terminal-pro hormone B-type natriuretic peptide level significantly decreased within one year. CONCLUSION: According to the results of our study, TAVR with a self-expanding THV is safe and feasible for patients with chronic severe AR, particularly for those who meet the criteria for the appropriate MDCT anatomical classification with intact dual aortic anchors, and it has a significant clinical effect for at least a year.

Feasibility study of temporary permanent pacemaker in patients with conduction block after TAVR.

Background: Limited data exist on the use of temporary permanent pacemaker (TPPM) to reduce unnecessary PPM in patients with high-degree atrioventricular block (HAVB) after transcatheter aortic valve replacement (TAVR). Objectives: This study aims to determine the feasibility of TPPM in patients with HAVB after TAVR to provide prolonged pacing as a bridge. Materials and methods: One hundred and eleven consecutive patients undergoing TAVR were screened from August 2021 to June 2022. Patients with HAVB eligible for PPM were included. TPPM were used in these patients instead of conventional temporary pacing or early PPM. Patients were followed up for 1 month. Holter and pacemaker interrogation were used to determine whether to implant PPM. Results: Twenty one patients met the inclusion criteria for TPPM, of which 14 patients were third-degree AVB, 1 patient was second-degree AVB, 6 patients were first degree AVB with PR interval > 240 ms and LBBB with QRS duration > 150 ms. TPPM were placed on the 21 patients for 35 ± 7 days. Among 15 patients with HAVB, 26.7% of them (n = 4) recovered to sinus rhythm; 46.7% (n = 7) recovered to sinus rhythm with bundle branch block. The remains of 26.7% patients (n = 4) still had third-degree AVB and received PPM. For patients with first-degree AVB and LBBB, PR interval shortened to < 200 ms in all 6 patients and LBBB recovered in 2 patients. TPPM were successfully removed from all patients and no procedure-related adverse events occurred. Conclusion: TPPM is reliable and safe in the small sample of patients with conduction block after TAVR to provide certain buffer time to distinguish whether a PPM is necessary. Future studies with larger sample are needed for further validation of the current results.

Key Residue in the Precursor Region of M Protein Contributes to the Neurovirulence and Neuroinvasiveness of the African Lineage of Zika Virus.

The Zika virus (ZIKV) represents an important global health threat due to its unusual association with congenital Zika syndrome. ZIKV strains are phylogenetically grouped into the African and Asian lineages. However, the viral determinants underlying the phenotypic differences between the lineages remain unknown. Here, multiple sequence alignment revealed a highly conserved residue at position 21 of the premembrane (prM) protein, which is glutamic acid and lysine in the Asian and African lineages, respectively. Using reverse genetics, we generated a recombinant virus carrying an E21K mutation based on the genomic backbone of the Asian lineage strain FSS13025 (termed E21K). The E21K mutation significantly increased viral replication in multiple neural cell lines with a higher ratio of M to prM production. Animal studies showed E21K exhibited increased neurovirulence in suckling mice, leading to more severe defects in mouse brains by causing more neural cell death and destruction of hippocampus integrity. Moreover, the E21K substitution enhanced neuroinvasiveness in interferon alpha/beta (IFN-α/ß) receptor knockout mice, as indicated by the increased mortality, and enhanced replication in mouse brains. The global transcriptional analysis showed E21K infection profoundly altered neuron development networks and induced stronger antiviral immune response than wild type (WT) in both neural cells and mouse brains. More importantly, the reverse K21E mutation based on the genomic backbone of the African strain MR766 caused less mouse neurovirulence. Overall, our findings support the 21st residue of prM functions as a determinant for neurovirulence and neuroinvasiveness of the African lineage of ZIKV. IMPORTANCE The suspected link of Zika virus (ZIKV) to birth defects led the World Health Organization to declare ZIKV a Public Health Emergency of International Concern. ZIKV has been identified to have two dominant phylogenetic lineages, African and Asian. Significant differences exist between the two lineages in terms of neurovirulence and neuroinvasiveness in mice. However, the viral determinants underlying the phenotypic differences are still unknown. Here, combining reverse genetics, animal studies, and global transcriptional analysis, we provide evidence that a single E21K mutation of prM confers to the Asian lineage strain FSS130125 significantly enhanced replication in neural cell lines and more neurovirulent and neuroinvasiveness phenotypes in mice. Our findings support that the highly conserved residue at position 21 of prM functions as a determinant of neurovirulence and neuroinvasiveness of the African lineage of ZIKV in mice.

SERTAD3 induces proteasomal degradation of ZIKV capsid protein and represents a therapeutic target.

Zika virus (ZIKV) is a mosquito-borne RNA virus that belongs to the Flaviviridae family. While flavivirus replication is known to occur in the cytoplasm, a significant portion of the viral capsid protein localizes to the nucleus during infection. However, the role of the nuclear capsid is less clear. Herein, we demonstrated SERTA domain containing 3 (SERTAD3) as an antiviral interferon stimulatory gene product had an antiviral ability to ZIKV but not JEV. Mechanistically, we found that SERTAD3 interacted with the capsid protein of ZIKV in the nucleolus and reduced capsid protein abundance through proteasomal degradation. Furthermore, an eight amino acid peptide of SERTAD3 was identified as the minimum motif that binds with ZIKV capsid protein. Remarkably, the eight amino acids synthetic peptide from SERTAD3 significantly prevented ZIKV infection in culture and pregnant mouse models. Taken together, these findings not only reveal the function of SERTAD3 in promoting proteasomal degradation of a specific viral protein but also provide a promising host-targeted therapeutic strategy against ZIKV infection.

The feasibility of relaxation-enhanced angiography without contrast and triggering for preprocedural planning of transcatheter aortic valve implantation.

Background: Cardiovascular MRI is advantageous in transcatheter aortic valve implantation (TAVI) planning. This study aimed to evaluate the feasibility of comprehensive non-contrast MRI [relaxation-enhanced angiography without contrast and triggering (REACT)] combined with a three-dimensional whole-heart MRI protocol for preprocedural planning of TAVI vs. computed tomography angiography (CTA). Methods: Thirty patients with severe aortic stenosis were prospectively enrolled. The anatomical properties of the aortic root anatomy, including the perimeter and area of the virtual aortic valve annulus and coronary heights, were determined from 3D whole-heart MRI and cardiac CTA (CCTA) images, respectively. The diameters of the aorta (thoracic and abdominal aorta) and iliofemoral arteries were measured from REACT and aortic CTA (ACTA) images, respectively. A paired t-test was used to compare these two modalities. Bland-Altman plots were used to assess cardiovascular MRI and CTA measurements. Transcatheter heart valve (THV) sizing was performed based on CCTA measurements and compared with 3D whole-heart MRI measurements. The extent of annular calcification on 3D whole-heart MRI images was evaluated by a four-point grading scale and compared with CCTA data. Results: All 30 patients completed CTA and cardiovascular MRI examinations, with the TAVI procedure being administered in 25 patients. The mean acquisition time of the comprehensive MRI protocol was 18 ± 3.2 min. There were no significant differences between ACTA and REACT data in regard to the diameters of aortic and iliofemoral arteries, including the ascending thoracic aorta (37 ± 4.6 mm vs. 37.7 ± 5.2 mm, p = 0.085), descending thoracic aorta (24.3 ± 2.8 mm vs. 24.3 ± 2.8 mm, p = 0.832), abdominal aorta (20.9 ± 2.5 mm vs. 20.8 ± 2.5 mm, p = 0.602), bilateral common iliac arteries (right: 8.36 ± 1.44 mm vs. 8.42 ± 1.27 mm, p = 0.590; left: 8.61 ± 1.71 mm vs. 8.86 ± 1.46 mm, p = 0.050), and bilateral femoral arteries (right: 6.77 ± 1.06 mm vs. 6.87 ± 1.00 mm, p = 0.157; left: 6.75 ± 1.02 mm vs. 6.90 ± 0.80 mm, p = 0.142). Both modalities showed similar aortic valve morphology and semi-quantitative valve calcification (all, p's > 0.05). Overall agreement for implanted THV was found in all 25 (100%) patients assessed with both modalities. Conclusion: REACT combined with 3D whole-heart MRI enables reliable measurements of aortic root anatomy, annular calcification, and aorta and iliofemoral access in patients under evaluation for TAVI.