Valve Function Research Articles

1083 RISK STRATIFICATION AND PREDICTORS OF OUTCOME IN ASYMPTOMATIC AORTIC STENOSIS: THE ROLE OF MULTIMODALITY IMAGING

Abstract Background Management of asymptomatic severe aortic stenosis is controversial and the decision to intervene requires careful assessment of the benefits and risks in an individual patient. Multimodality imaging approach is becoming an important tool to evaluate the severity and outcome of aortic stenosis (AS). Aim To assess the outcome of asymptomatic AS and the usefulness of aortic calcium score (CS) by computed tomography (CT) for solving the dilemma of low-flow, low-gradients (LFLG) severe AS. Methods 70 (81.4±8.4yrs) prospective asymptomatic patients with AS were followed for 2.77±2.01yrs with a trans-thoracic echo (TTE) every 6 months. End-points were all cause mortality, aortic valve replacement (AVR or TAVR), aortic velocity and gradients progression and symptoms occurrence. Prevalence of LFLG-AS was investigated and these patients underwent CT for CS calculation at the end of follow-up (FU), Figure 1. Results Baseline TTE results from the 70 pts were: peak velocity 3.1±0.8m/sec; peak gradient 44±21mmHg; mean gradient 26±14 mmHg; AVA 1±0.3 cm2; DVI 0.31 ±0.1; Svi 33.8±18 ml/m2; EF: 55±9% with an AS being mild in 32.9%, moderate in 28.4%, severe in 27.1%; 36.8% of severe AS were LFLG. During FU, 23 (32.8%) pts died (5.7% LFLG) and 13(18.5%) underwent AVR/TAVR. Predictors of mortality were aortic gradients (p=0.03), AVA (p=0.008), DVI (p<0.001), pulse pressure (p=0.005) and dilated ascending aorta (p<0001). Predictors of AVR/TAVR were: gradients (p=0.003), peak aortic velocity (p=0.02) and dilated ascendent aorta (p=0.01). The best cut-off to predict survival was AVA =1cm2 (100% sensitivity and 80% specificity). In 34 pts ending FU we found an overall progression of AS severity (peak velocity 3.6±0.9m/sec; peak gradient 50±24mmHg; mean gradient 33±15 mmHg; AVA 0.7±0.3 cm2; DVI 0.25±0.08; Svi 36±10 ml/m2; EF 54±10%; p<0.05 for all vs baseline) with 24 (70.5%) pts with severe AS and 10 (29.5%) with not severe AS. 18 (75%) of progressive severe AS were LFLG, 12 asymptomatic and 6 symptomatic and all underwent CS revealing that AS was not severe in 6 (1233±1123 AU; 622±55AU/m2) and true severe in 12 (3388±1188 AU;1858 ±795 AU/m2; p=0.005 and p=0.002, respectively). Symptomatic severe LFLG AS were all true severe according to CS (Figure 1). Table 1 shows the main CS correlations. Conclusions Asymptomatic AS in elderly people is associated with high mortality risk and rapid progression. AVA remains the best predictor of outcome. In severe LFLG AS, calcium score correlates with symptoms occurrence, progression of valve disease, LV hypertrophy and function and also with RV function.

322 TRICUSPID VALVE REGURGITATION AFTER TRANSVENOUS LEAD EXTRACTION: WE NEED TO KNOW MORE

Abstract Since 2003 a 73-year-old man was submitted to a pacemaker implantation because of atrio-ventricular block. After fourteen years, upgrading to CRT-D was made due to recovery for acute heart failure in a dilated cardiomyopathy with severe left ventricular systolic dysfunction. In 2019 and 2020 he presented pocket erosion therefore underwent to a submuscular reimplantation. After one year, he came to Arrhythmology outpatient appointment with inflammatory signs of the CRT-D pocket. The patient was started on Meropenem and Vancomicin. Transthoracic (TTE) and transesophageal echocardiogram didn't reveal any vegetation on valvular apparatus or on leads. The patient was submitted to transvenous lead extraction (TLE) with bidirectional rotational mechanical sheats and a epicardial lead on postero-lateral left ventricular wall was implanted. The post-procedural TTE showed a moderate to severe organic tricuspid valve regurgitation with annular dilatation despite the patient was asymptomatic. There weren't flail leaflets or tricuspid valve damage. The reimplantation of right atrial and ventricular leads was hindered by complex venous anatomy documented by intraprocedural phlebography. After Heart Team discussion, we agreed to tricuspid valve repair with annuloplasty ring and other two epicardial leads - right atrial and ventricular - was implanted. We achieve a successful result without complications. The patients was discharged without symptoms; the device interrogation showed good assessment of lead impedances, sensing thresholds, and capture thresholds. Conclusion The mechanisms of tricuspid valve regurgitation following TLE are complex. There isn't a standardized best practice to approach this phenomenon. It's important after TLE to assess tricuspid valve structure and function with TTE in order to understand the incidence of underlying potential mechanism and how to prevent it. Complex venous anatomy could direct the choice toward epicardial leads implantation.

489 A RARE CASE OF LEAD EXTRACTION

Abstract Aims Poor data exist about the leadless PM implantation through a bioprosthetic tricuspid valve. Bioprosthetic tricuspid valve has traditionally represented a relative contraindication to transvenous right ventricular pacing for possible tricuspid bioprosthetic valve damage and dysfunction. Therefore, epicardial pacing is usually preferred to transvenous right pacing through a bioprosthetic tricuspid valve for the deleterious effect of permanent pacing leads on tricuspid bioprosthetic valve function and regurgitation. Methods Our case focuses on a 62-year-old woman with mechanical mitral and biological tricuspid prosthesis due to rheumatic disease since 2007 and with a PM-DDDR for a postsurgical complete atrioventricular block. A lead was implanted in right atrium while another lead was implanted in the coronary sinus (CS) instead of in the right ventricle following the presence of a biological tricuspid prosthesis. In February 2022, she did a replacement of pacemaker (PM) generator to another hospital due to initial battery depletion. In March she described pain at the device pocket and consequent appearance of pocket infection. For this situation she was admitted to our cardiac department. A transesophageal echocardiography (TEE) was performed and showed normal biventricular size and function (LVEF 55%), normal function of valve prostheses and absence of vegetations both on the valves and atrial lead. Subsequently an angiography was performed and revealed little patency of the anonymous-caval-subclavian left axis. We made a diagnosis of pocket infection and decided to extract leads in March. We proceded through debridement of leads and removal of the PM generator. After placing Spectranetics (Philips) Lead Locking Device n.2 (LLD2) along the 2007 right atrial lead, we removed it through the use of a mechanical extractors (Cook 7-8.5 Fr). Then after placing Spectranetics (Philips)Lead Locking Device E (LLDE), the CS lead was completely removed through the use of a mechanical extractors (Cook 7-8.5 Fr) and specific delivery.The procedure was well tolerated and uneventful. Following the negative result of the post-extraction blood cultures, cultures of lead tips and pocket swab, together with the normalization of inflammation indices (WBC and CRP) and to the end of antibiotic therapy, we decided to reimplant the device.For the presence of valve prostheses and the patient's high infectious risk, we decided to implant a leadless PM. Results At the beginning of April we performed a leadless Micra AV PM implantation through 23-F Micra TPS delivery catheter across a tricuspid bioprosthetic valve in the right ventricular apex instead of the middle septum due to implantation difficulties for the concomitant presence of the bioprosthetic valve. The procedure was well tolerated and uneventful too. She was discharged after 72h in good conditions. Conclusions We present an unusual case of lead extraction for the second infection of the device pocket in a patient with mechanical mitral and biological tricuspid prostheses and a lead in coronary sinus for the presence of biological tricuspid prosthesis. Leadless PM implantation represents a new technology by eliminating the risks connected with the presence of the lead across the bioprosthetic valve.

Design and Analysis of a New Pressure Relief Valve for Oil-Immersed Electrical Equipment

Abstract Internal arcing in oil-immersed electrical equipment is inevitable and of great danger. Transient overpressure should be released by protectors quickly and controllably. Currently available pressure relief valves cannot fully protect the electrical equipment due to mismatch between insufficient relief capacity with correspondingly weak valve structure and increasing arcing energy in upgrading electrical systems. Additionally, flaming possibility of ejected high-temperature oil–gas mixture is distinct, and retained oil in an oil tank without any isolation may be ignited by the flame. Unfortunately, resealing of some existing single-outlet valves is out of control due to asymmetrical hydraulic pressure distribution on the valve plate which causes unstable valve plate movement. Therefore, a new pressure relief valve characterized by symmetrical outlets and improved pressure relief capacity was developed. The novel structure and function of the new valve was first introduced, and comprehensive analysis regarding dynamic performances, strength and fluid development during the relief process were conducted. Finally, a prototype was manufactured and tested on a specific arcing test system. The developed valve can well release the overpressure generated by a 6 MJ equivalent arcing fault without any flame during the entire relief process. Furthermore, the valve structure can withstand the pressure load, and valve plate can precisely reseal the oil tank due to optimized fluid pressure distribution. This research provides an optimized pressure relief valve and a design guide for improved pressure relief valve.

Quantitative invivo assessment of human mitral valve coaptation area after undersized ring annuloplasty repair for ischemic mitral regurgitation.

Long-term outcomes of mitral valve repair procedures to correct ischemic mitral regurgitation remain unpredictable, due to an incomplete understanding of the disease process and the inability to reliably quantify the coaptation zone using echocardiography. Our objective was to quantify patient-specific mitral valve coaptation behavior from clinical echocardiographic images obtained before and after repair to assess coaptation restoration and its relationship with long-term repair durability. To circumvent the limitations of clinical imaging, we applied a simulation-based shape-matching technique that allowed high-fidelity reconstructions of the complete mitral valve in the systolic configuration. We then applied this method to an extant database of human regurgitant mitral valves before and after undersized ring annuloplasty to quantify the effect of the repair on mitral valve coaptation geometry. Our method was able to successfully resolve the coaptation zone into distinct contacting and redundant regions. Results indicated that in patients whose regurgitation recurred 6months postrepair, both the contacting and redundant regions were larger immediately postrepair compared with patients with no recurrence (P<.05), even when normalized to account for generally larger recurrent valves. Although increasing leaflet coaptation area is an intuitively obvious way to improve long-term repair durability, this study has implied that this may not be a reliable target for mitral valve repair. This study underscores the importance of a rigorous understanding of the consequences of repair techniques on mitral valve behavior, as well as a patient-specific approach to ischemic mitral regurgitation treatment within the context of mitral valve and left ventricle function.

De ventielfunctie van de artikel 12 Sv-procedure: van georganiseerd wantrouwen naar gezamenlijk politiek project?

Originally, Article 12 of the Dutch Code of Criminal Procedure was intended as a correction mechanism for the prosecution monopoly of the Public Prosecution Service. In a later stage, the private interest of complainants (or victims) became more central. This article argues that a third function now emerges: a valve function for social dissatisfaction. The social conflicts that underly the proceedings in these socially sensitive cases give rise to new democratic legitimacy problems. However, an appropriate normative framework that captures these new democratic demands has not yet been constructed. To this end, this article provides an alternative democratic vocabulary in order to bridge the gap between empirical and normative notions of legitimacy. By means of a historical and normative analysis, it will be argued that Article 12 has an important democratic potential within the characteristically autonomous Dutch system of criminal law.

Optimization on Blowdown Flow Regulation Characteristics of Steam Generator in a Nuclear Power Plant

During the operation of a nuclear power plant, the blowdown flow measurement signal of the steam generator fluctuates frequently, which interferes with the automatic adjustment function of the flow control valve. When the signal fluctuation reaches the alarm value, the flow control valve will be closed automatically, isolating the steam generator blowdown system, and affect the water quality regulation of the secondary circuit. Through the analysis of the system design, operating conditions and equipment structure, it is shown that due to the blocked flow of the flow regulating valve, the flowmeter is affected by the two-phase flow. In view of the problems, this paper proposes improvement measures from the rationality of flowmeter selection, the optimization of system control logic parameters, and the system multistage depressurization.

History of the development of the lymphatic system (part two)

The eighteenth century can rightly be considered the time of the most remarkable inventions in studying the lymphatic system. The Swiss Johann Conrad Peyer (1653–1712), in his "Exercitatio anatomico-medica de glandulis intestinorum earumque usu et affectionibus" (1677) described the presence of organized lymphatic vessels in the mucous membrane of the small intestine, which are named Peyer's plaques in his honor. Alexander Monro from the University of Edinburgh Medical School was the first to describe the function of the lymphatic system in detail. In 1701, Dutch botanist and anatomist Frederick Ruysch (1638-1731), a student of Van Horn, described the morphology and function of lymphatic valves. Another Dutch anatomist, Anton Nyuck (1650-1692), used the mercury injection technique to demonstrate the lymphatic system. The French anatomist Raymond Vuyssens (1641-1715), a pioneer in cardiac and nervous system anatomy, published his groundbreaking work in Nouvelles Découvertes sur le Coeur (1706) detailing the lymphatic system of the heart. The Italian histologist and microscopist Marcello Malpighi (1628–1689) gave a great impetus to the development of microanatomy with his pioneering microscope. New progress in the knowledge of the lymphatic system was provided by the English Hunter brothers. William Hunter (1718-1783) clearly suggested that lymphatic and milk vessels have two different properties that contribute to the formation of a single network of vessels endowed with an absorbing function. In 1731, Antonio Leprotti published a dissertation on the roots of the human lymphatic system. The Italian anatomist Paolo Mascagni (1755-1815) developed a special instrument with glass tubes for slowly introducing mercury into the lymphatic vessels. In the same year, 1787, Paolo Assalini published an essay on the lymphatic system, where the author tried to demonstrate the existence of "air-conducting" vessels. Like Nyuck and Mascagna, Vincenzo Foman (1794-1837) used mercury to inject the smallest lymphatic vessels. Another contribution to understanding the anatomy of the lymphatic system made the French anatomist Marie Philibert Constant Sappey (1810-1896), who was able to count the valves in the lymphatic vessels. The Polish pathologist Alfred Besiadecki (1839-1889) made a great contribution to the study of the lymphatic system of the skin. Thanks to his research, he refuted the prevailing hypothesis that the blood capillaries in the skin are located inside the lymphatic vessels. For the first time in history, he described the contiguous connection between lymphatic and blood vessels. In 1858, Carl Friedrich Wilhelm Ludwig (1816-1895) proposed the hypothesis that lymph is a filtrate of blood that is released from the capillary wall under the influence of intracapillary pressure. After that, the British doctor William Handley significantly contributed to the development of surgery for lymphatic disorders. In 1908, he introduced his technique of "lymphangioplasty". One of the key figures of this lymphatic revolution and "renaissance" is undoubtedly the Finnish researcher Kari Kustaa Alitalo (1952-present), who, together with his group and in collaboration with other international groups, made the most important discoveries regarding the growth factor/receptor system that controls the development of lymphatic vessels and lymphatic metastases of tumors.

Reconsideration and surgical technique report of root repair management of acute Stanford type A aortic dissection.

Currently, there is a lack of expert consensus and clinical guidelines about the treatment strategy for aortic roots in patients with acute Stanford type A aortic dissection with aortic sinuses less than 45 mm in diameter and without combined connective tissue disorder. The physiological aortic sinus plays a key role in the protection of the aortic valve and cardiac function. Thus, we invented a "watching without dealing with" technique of aortic root repair to preserve the aortic sinus as much as possible. This technique could simplify the operation and improve the patient's prognosis, which is worth learning and promoting.

Abnormally elevated EZH2-mediated H3K27me3 enhances osteogenesis in aortic valve interstitial cells by inhibiting SOCS3 expression

Background and aimsThe osteogenic transition of aortic valve interstitial cells (AVICs) plays a critical role for the progression of calcific aortic valve disease (CAVD). Enhancer of zeste homolog 2 (EZH2) is an important methyltransferase for histone H3 Lys27 (H3K27) that has been found to be involved in osteogenesis. Here, we investigated the effect and mechanism of EZH2 in CAVD progression. MethodsHigh throughout mRNA sequencing, qRT-PCR and immunoblot were performed to screen differentially expressed genes in non-CAVD and CAVD aortic valves. To investigate the role of EZH2 and SOCS3 in osteogenesis, AVICs were treated with siRNA, adenovirus and specific inhibitors, then osteogenic markers and mineralized deposits were examined. In vivo, the morphology and function of aortic valves were investigated by HE stain and echocardiography in ApoE−/− mice fed a long-term western diet (WD). ResultsWe discovered that EZH2 was upregulated and SOCS3 was downregulated in calcified aortic valves. In AVICs, inhibition or silencing of EZH2 attenuated the osteogenic responses. On the other hand, demethylases inhibitor (GSK-J4) enhanced osteogenic transition of AVICs. Moreover, SOCS3 knockdown enhanced the expression of osteogenic markers, while SOCS3 overexpression suppressed osteogenesis and calcification. The chromatin immunoprecipitation and restored experiments indicated that EZH2 directly targeted SOCS3 to promote osteogenic responses of AVICs. In vivo, treatment with EZH2 inhibitor through intraperitoneal injection attenuated aortic valve thickening, calcification and dysfunction induced by WD. ConclusionsCollectively, we found that EZH2-mediated H3K27me3 enhanced osteogenesis and microcalcification of AVICs via inhibiting SOCS3 expression, which provides potential targets for future therapeutic interventions of CAVD.

Role of cardiac magnetic resonance (CMR) in planning ventricular septal myomectomy in patients with hypertrophic obstructive cardiomyopathy (HOCM).

Septal myectomy is currently the gold standard treatment for symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM). The procedure needs to be tailored and performed in a personalized fashion, taking into consideration the anatomic and physiologic heterogeneity of this disease. The extent and location of surgical myectomy will depend on the location of the hypertrophy, with the goal of widening the outflow tract and improve the function of the mitral valve. CMR helps to identify hypertrophy not well visualized by TTE, providing more accurate wall thickness measurements and differentiating HOCM from other causes of LV hypertrophy. CMR also helps identify an abnormal attachment of papillary muscle to the MV or to the septal myocardium and mitral valve pathology. A collaborative approach with cardiac surgeons, radiologists and cardiologists will optimize preoperative planning to improve the success for surgical myectomy.

Early results of Pulsta® transcatheter heart valve in patients with enlarged right ventricular outflow tract and severe pulmonary regurgitation due to transannular patch.

The purpose of this study is to assess the feasibility, effectivity, and safety of a novel self-expandable valve system, Pulsta® transcatheter heart valve in patients with tetralogy of fallot and severe pulmonary regurgitation after transannular patch repair. Severe pulmonary regurgitation after tetralogy of fallot repair is a life-threatening problem and should be treated by pulmonary valve implantation. Although percutaneous pulmonary valve implantation has been ever increasingly used for this purpose, available balloon-expandable valves have limitations and cannot be used by most patients. Pulsta® transcatheter heart valve is a new self-expandable valve system and offers a new solution to be used in patients with different types of native right ventricular outflow tract geometry. Ten patients with severe regurgitation after tetralogy of fallot repair with a transannular patch have been enrolled in the study according to echocardiographic examination. MRI was used in asymptomatic patients to delineate the indication and the right ventricular outflow tract geometry. Pulsta® transcatheter heart valve implantation was performed in ten patients, and preprocedural, procedure, and 6 months follow-up findings of the patients were evaluated. Pulsta® pulmonary valve implantation was performed in ten patients successfully without any severe complications. Valve functions were perfect in six of ten patients, while the others had insignificant regurgitation by echocardiographic examination at the end of 6 months follow-up. This study showed that Pulsta® transcatheter heart valve is a feasible, effective, and safe method in the treatment of severe pulmonary regurgitation due to transannular patch repair in patients with tetralogy of fallot.

Influence of Bends in the Functionality of Passive Explosion Isolation Valves

Explosion isolation flap valves are one of the most used explosion protection systems in process industries; research is essential to improve them and to minimise both human and material losses when dust explosions take place. In this regard, there is little knowledge on the effect of bends in the functionality of these protective systems; hence, the main aim of this work is to bridge this gap. Large-scale dust explosions were performed, using three different types of dust: metal dust and two types of organic dust. In order to analyse the effect of bends in the functionality of these protective systems, results using a straight duct and one with bends were compared for each dust tested. In addition, the influence of the bend radius on aluminium dust explosions was also evaluated. The results indicated that the effect of bends depended on the explosive characteristics of the dust. However, for aluminium and maize starch dusts, bends led to higher pressures and flame velocities. Relevant information is provided to help decision-making when designing these valves. Moreover, such data can be used for consideration in the discussions held by the task force entrusted with developing the standard used to assess their functionality.

Perspectives on pediatric congenital aortic valve stenosis: Extracellular matrix proteins, post translational modifications, and proteomic strategies.

In heart valve biology, organization of the extracellular matrix structure is directly correlated to valve function. This is especially true in cases of pediatric congenital aortic valve stenosis (pCAVS), in which extracellular matrix (ECM) dysregulation is a hallmark of the disease, eventually leading to left ventricular hypertrophy and heart failure. Therapeutic strategies are limited, especially in pediatric cases in which mechanical and tissue engineered valve replacements may not be a suitable option. By identifying mechanisms of translational and post-translational dysregulation of ECM in CAVS, potential drug targets can be identified, and better bioengineered solutions can be developed. In this review, we summarize current knowledge regarding ECM proteins and their post translational modifications (PTMs) during aortic valve development and disease and contributing factors to ECM dysregulation in CAVS. Additionally, we aim to draw parallels between other fibrotic disease and contributions to ECM post-translational modifications. Finally, we explore the current treatment options in pediatrics and identify how the field of proteomics has advanced in recent years, highlighting novel characterization methods of ECM and PTMs that may be used to identify potential therapeutic strategies relevant to pCAVS.

SmDXS5, acting as a molecular valve, plays a key regulatory role in the primary and secondary metabolism of tanshinones in Salvia miltiorrhiza.

Red sage, the dry root and rhizome of the herbaceous plant Salvia miltiorrhiza Bunge, is widely used for treating various diseases. The low content of tanshinones (terpenoids) has always restricted development of the S. miltiorrhiza industry. Here, we found that SmDXS5, a rate-limiting enzyme-coding gene located at the intersection of primary and secondary metabolism, can effectively change the transcription level and secondary metabolome profile of hairy roots of S. miltiorrhiza, and significantly increase the content of tanshinones. Agrobacterium rhizogenes was used to infuse S. miltiorrhiza explants, and hairy roots of S. miltiorrhiza expressing the SmDXS5 gene were obtained successfully. We identified 39 differentially accumulated metabolites (DAMs) by metabolomics based on ultra-high performance liquid chromatography quadrupole exactive mass spectrometry and multivariate statistics. These DAMs might be key metabolites of SmDXS5 gene regulation. RNA sequencing was used to compare gene expression between the hairy roots of the SmDXS5 overexpressing group and the blank control (BC) group. Compared with the BC group, 18,646 differentially expressed genes were obtained: 8994 were upregulated and 9,652 downregulated. The combined transcriptome and metabolome analyses revealed that the mevalonate and methylerythritol phosphate pathways and synthase gene expression levels in the SmDXS5 overexpressing group were upregulated significantly, and the accumulation of tanshinone components was increased significantly, which promoted the process of glycolysis and promoted the transformation of carbohydrates to secondary metabolism. Moreover, the expression of SmPAL, the first rate-limiting enzyme gene of the phenylpropane pathway, decreased, reducing the accumulation of phenolic acid, another secondary metabolite. Therefore, SmDXS5 can be defined as a 'valve' gene, mainly responsible for regulating the distribution of primary and secondary metabolic flow of tanshinones in S. miltiorrhiza, and for other secondary metabolic pathways. The discovery of SmDXS5 and its molecular valve function in regulating primary and secondary metabolism will provide a basis for the industrial production of tanshinone components, and cultivation of high quality S. miltiorrhiza.

Abstract 13931: Comparison of Inpatient Outcomes of Transcatheter Aortic Valve Replacement in Bicuspid versus Tricuspid Aortic Valve Stenosis: An Insight From National Inpatient Sample

Background: TAVR is increasingly performed in patients with severe aortic stenosis (AS), including those with bicuspid aortic valve (BAV). There is a paucity of data on the safety and efficacy of TAVR in the latter group since they were excluded from the landmark trials which established TAVR as a favorable alternative to surgery. Prior studies have shown higher rates of permanent pacemaker placement (PPM) and paravalvular leak (PL) but comparable rates of embolic stroke (ES) and mortality in BAV patients who underwent TAVR when compared to those with tricuspid aortic valve (TAV). We examined the impact of aortic valve anatomy on inpatient mortality and complication rates using current data from the largest inpatient database in the United States.Methods:We queried the 2016-2019 National Inpatient Sample database to identify all patients over 18 years of age who underwent TAVR for AS. Patients were stratified to BAV and TAV groups using ICD-10 codes. Greedy nearest neighbor propensity score matching was performed based on demographics, Charlson comorbidity index, hospital characteristics, insurance status, and median income. Outcomes of interest included rates of mortality, PPM, PL, ES, and length of hospital stay (LOS).Results:Of 192,100 AS patients who underwent TAVR, 0.5% had BAV. After propensity score matching, 995 BAV and 995 TAV patients were included in the final analysis. The overall mortality rate was 1.5% with no significant difference between the two groups [OR 1.00 (0.20-5.060), p=1.00]. Rates of PPM were 10.1% in BAV and 8.5% in TAV patients with no significant difference [OR 1.20 (0.61-2.37), p=0.61]. Rates of PL were 1% in BAV and 0.5% in TAV patients with no significant difference [OR 2.01 (0.18-22.65), p=0.57]. Rate of ES was 1.5% in BAV patients; however, direct comparison to its propensity-matched TAV cohort was not feasible since the latter group had no events in this analysis. There was no significant difference in the LOS between the two groups.Conclusion:Insight from this large database suggests that in the current era, TAVR has similar short-term outcomes in both BAV and TAV patients. Further studies with long-term follow-up on valve function and the need for reintervention will be needed, especially since this involves younger patients.

Abstract 9903: Artificial Intelligence Driven Wearable 2-minute Seismocardiography Test for Detection of Aortic Valve Stenosis Severity

Introduction: Standard diagnosis of aortic valve stenosis (AS) requires clinical imaging by echocardiography or cardiac MRI. The purpose of this study was to test the performance of easy to use, artificial intelligent (AI) driven seismocardiogram (SCG) chest acceleration recordings for point of care screening and identification of AS. Hypothesis: SCG measurements can be used by a low dimensional convolutional neural network (CNN) to accurately predict presence or absence of aortic valve stenosis (AS) and severity of dysfunction. Methods: This IRB approved study included 45 controls (age 46±17y, 20 F, no known cardiovascular disease) and 30 aortic valve disease (AVD) patients (age 30±20y, 7 F, 21 bicuspid). A wearable SCG device (integrated ECG/accelerometer microelectronics) was placed for 2min chest acceleration recordings on the same day as standard of care echocardiography or cardiac MRI, which was used as ground truth data to classify valve function (normal: AS-, mild AS: AS+, moderate/severe AS: AS++). A deep learning CNN (2х2 kernel, softmax/cross entropy classification) was configured to predict/detect degree of AS from spectrally decomposed SCG measurements. Randomized 50% split of subjects was used for CNN training/testing. Performance detecting AS was evaluated for classification accuracy. Results: AI driven SCG detection of valve function abnormality had high sensitivity/specificity (90%, 67%) with a net area under curve (AUC) 0.86. Correct classification of the degree of AS was achieved in 76% of subjects. Normal (AS-) vs abnormal function (AS+ or AS++) was accurately identified by AI driven SCG for 86% of subjects. Conclusions: This feasibility study demonstrates that the combination of easily measured 2 minute SCG with a deep processing pipeline could successfully detect the presence and severity of AS, supporting clinical promise for potential use as a low cost, front line screening tool to identify patients with aortic valve dysfunction.

Abstract 14024: Role of Endothelial CXCR4 on the Development of Aortic Valve Stenosis

Background. CXCL12/CXCR4 signaling is essential in cardiac development and repair, however, its contribution to the Aortic valve stenosis (AVS) remains unclear. In this study, we tested the role of endothelial CXCR4 on the development of AVS. Methods. We generated CXCR4 endothelial cell-specific knockout mice (EC CXCR4 KO) by crossing CXCR4 fl/fl mouse with Tie2-Cre mouse to study the role of endothelial cell CXCR4 in AVS. CXCR4 fl/fl mice with no Tie2-Cre gene present were used as control. Echocardiography was used to assess the aortic valve and cardiac function. Heart samples containing the aortic valve were stained using Alizarin Red for detection of calcification. Masson’s Trichrome staining was used for the detection of fibrosis. Apex samples were stained with wheat germ agglutinin to visualize ventricular hypertrophy. Results. Compared with the control group, the deletion of CXCR4 in endothelial cells led to significantly increased aortic valve peak velocity and aortic valve peak pressure gradient, and decreased aortic valve area and ejection fraction. EC CXCR4 KO mice also developed cardiac hypertrophy evidenced by increased left ventricular mass, diastolic and systolic left ventricle posterior wall (LVPW), cardiac myocyte size, and heart weight (HW) to body weight (BW) ratio. Our data also confirmed increased microcalcifications, interstitial fibrosis, and thickened valvular leaflets of the EC CXCR4 KO mice. Conclusions. We found that the deletion of CXCR4 in endothelial cells leads to aortic valve stenosis and left ventricular hypertrophy. This indicates endothelial cell CXCR4 plays a protective role against AVS, and EC CXCR4 KO mice can be used as a novel model for AVS study.

Abstract 15467: Bi-Leaflet Tricuspid Valve in Children With Hypoplastic Left Heart Syndrome is Rarely Incompetent, While Bi-Leaflet With a Cleft Results in Tricuspid Valve Regurgitation

Introduction: Tricuspid valve (TV) regurgitation in Hypoplastic Left Heart Syndrome (HLHS) increases the risk of death/transplantation by 2 to 3 times. Abnormalities in TV annular shape, leaflets expansion and subvalve apparatus position, have been associated in HLHS with subsequent tricuspid regurgitation (TR). As TV morphological variation is increasingly recognized, its role on tricuspid valve function remains unknown. This study aims to describe and examine the relationship between the TV leaflet morphologies in HLHS and its association with TV repair. Methods: Cross sectional study of selected 38 “classic” HLHS patients from a prospective longitudinal 3DE study of HLHS TV. TV leaflet morphology from 3DE datasets were reviewed (S.Z and N.S.K) blinded to TR grade. We adapted a previously proposed nomenclature to describe the TV leaflets (Figure 1). Using the Chi-squared test, we compared the frequencies of TV morphological types of HLHS with mild or less TR (n = 23) vs. HLHS who had TV repair (n = 15) at latest follow up. Results: Incidence of TV morphological type is summarized in Figure 2. Bi-leaflet TV was the second most common, followed by bi-leaflet with a cleft. When comparing HLHS with mild or less TR vs. HLHS with TVR, only 1 of 9 bi-leaflet TV had subsequent TVR, while all bi-leaflet TV with a cleft, underwent TVR (p&lt;0.05). Conclusion: HLHS has considerable TV leaflet variations with bi-leaflet TV being the second most common variation. While bi-leaflet TV is more likely to be found in a competent TV, those with a bi-leaflet TV with a cleft, all required TVR. Bi-leaflet TV with a cleft, warrants further study to assess its relationship and relative role with TVR.

Abstract 13878: A Case of Severe Tricuspid Regurgitation, Recurrent Ascites, Worsening Renal Function Leading to Hemodialysis Secondary to RV Lead Impingement, Resolved Completely With Lead Extraction

Introduction: 1. In contemporary practice, implantation of Cardiovascular Implantable Electronic Devices (CIED) is associated with low complication rate peri-procedurally. 2. However, in some patients these complications can have high morbidity and mortality; namely pneumothorax, pericardial tamponade, pacemaker syndrome, and rarely tricuspid regurgitation (TR) secondary to lead impingement. 3. TR secondary to RV lead impingement is not uncommon but infrequently lead to severe TR and worsening heart failure symptoms. 4. We present a case of severe TR secondary to RV lead impingement leading to splanchnic congestion and recurrent ascites, worsening renal failure leading to hemodialysis (HD), all of which resolved with lead extraction. Case: A 77-year-old woman with known CAD with prior PTCA, paroxysmal AF, and prior watchman implantation, evaluated in our clinic for severe TR. She had recurrent admissions for ascites needing paracentesis. Her liver function and ultrasound was normal. Her renal function worsened and HD was initiated. ECHO showed normal LVEF, severe TR with RVSP of 74mmHg, and mild RV dysfunction. Pericardial physiology was normal. The lead was noted to be impinging on the septal leaflet, and adherent. Normal pulmonary valve function. Follow up: We proceeded to perform RV lead extraction and implanted a new leadless pacemaker [MICRA-AV, Medtronic Inc]. Her follow up ECHO in 2 weeks showed mild TR and normal RV function. RVSP had dropped significantly to 34mmHg. Surprisingly, her needs for paracentesis came down and by 3 months follow up she did not need paracentesis anymore. Her renal function improved, and her HD needs stopped. Conclusions: 1. CIED implantations are associated with low complication rate (less than 5% in total) in most patient cohorts but in some patients it can be associated with significant complications increasing their morbidity and sometimes mortality. 2. Severe TR is a well-recognized complication of pacemaker implantation. It led to recurrent ascites needing paracentesis, ESRD requiring HD and multiple hospital admissions and thus increasing the morbidity. 3. It is important to recognize the uncommon complications of such commonly used intracardiac devices for electrophysiologists, cardiologists and PCPs.