Prosthetic Leaflet Research Articles

Effect of Blood Pressure Levels on Sinus Hemodynamics in Relation to Calcification After Bioprosthetic Aortic Valve Replacement.

Coexisting hypertension and aortic stenosis are common. Some studies showed that elevated blood pressures may be associated with progression of calcific aortic valve disease (CAVD) while others showed no correlation. Flow dynamics in the sinuses of Valsalva are considered key factors in the progression of CAVD. While the relationship between hemodynamics and CAVD is not yet fully understood, it has been demonstrated that they are tightly correlated. This study aims to investigate the effect of changing systolic and diastolic blood pressures (SBP and DBP, respectively) on sinus hemodynamics in relation to potential initiation or progression of CAVD after aortic valve replacement (AVR). Evolut R, SAPIEN 3 and Magna valves were deployed in an aortic root under pulsatile conditions. Using particle image velocimetry, the hemodynamics in the sinus were assessed. The velocity, vorticity, circulation ( and shear stress were calculated. This study shows that under elevated SBP and DBP, velocity, vorticity, and shear stress nearby the leaflets increased. Additionally, larger fluctuations of and area under the curve throughout the cardiac cycle were observed. Elevated blood pressures are associated with higher velocity, vorticity, and shear stress near the leaflets which may initiate or accelerate pro-calcific changes in the prosthetic leaflets leading to bioprosthetic valve degeneration.

Current Usefulness of Transesophageal Echocardiography in Patients Undergoing Transcatheter Aortic Valve Replacement.

This review article describes in depth the current usefulness of transesophageal echocardiography in patients who undergo transcatheter aortic valve replacement. Pre-intervention, 3D-transesophageal echocardiography allows us to accurately evaluate the aortic valve morphology and to measure the valve annulus, helping us to choose the appropriate size of the prosthesis, especially useful in cases where the computed tomography is not of adequate quality. Although it is not currently used routinely during the intervention, it remains essential in those cases of greater complexity, such as for patients with greater calcification and bicuspid valve, mechanical mitral prosthesis, and "valve in valve" procedures. Three-dimensional transesophageal echocardiography is the best technique to detect and quantify paravalvular regurgitation, a fundamental aspect to decide whether immediate valve postdilation is needed. It also allows to detect early any immediate complications such as cardiac tamponade, aortic hematoma or dissection, migration of the prosthesis, malfunction of the prosthetic leaflets, or the appearance of segmental contractility disorders due to compromise of the coronary arteries ostium. Transesophageal echocardiography is also very useful in follow-up, to check the proper functioning of the prosthesis and to rule out complications such as thrombosis of the leaflets, endocarditis, or prosthetic degeneration.

A photo-triggered coating of prosthetic valve leaflet surface to realize antibacterial and thrombolysis on-demand

Thrombosis formation and bacterial infection pose significant challenges in the clinical application of long-term implanted prosthetic heart valves (PHV), and the two challenges generally occurred in the middle and late stages of implantation. So, it would be very valuable for PHV to realize antibacterial and thrombolysis “on-demand”. In this study, we constructed a photo-triggered coating to simultaneously address the above both challenges based on photodynamic therapy (PDT), which has been widely researched due to its advantage of spatiotemporal control. The photosensitizer chlorin e6 (Ce6) were grafted onto the polyethyleneimine (PEI) and introduced into the coating by layer-by-layer (LBL) technology. Under near-infrared (660 nm) irradiation, the coating could release reactive oxygen species (ROS), effectively destroy bacterial walls and disintegrating the fibrin three-dimensional network structure of formed thrombi. Therefore, the coating exhibited dual functionality of antibacterial and thrombolysis “on-demand”. Experimental results demonstrated that the coating effectively eradicated gram-positive and gram-negative bacteria both in vitro and in vivo, as well as causing thrombolysis under irradiation. These results highlight the potential of this coating in improving the anticoagulation and antibacterial properties of prosthetic heart valves and other long-term implanted devices.

Impact of balloon post-dilation on valve durability and long-term clinical outcomes after self-expanding transcatheter aortic valve implantation.

Balloon post-dilation (BPD) is a widely adopted strategy to optimize acute results of TAVI, with a positive impact on both paravalvular leak and mean gradients. On the other hand, the inflation of the balloon inside prosthetic leaflets may damage them increasing the risk of structural valve deterioration (SVD). Furthermore, the impact of BPD on long-term clinical outcomes and valve hemodynamics is yet unknown. To evaluate the impact of BPD on valve durability and long-term clinical outcomes in patients undergoing self-expanding transcatheter valve implantation (TAVI). Echocardiographic and clinical data from the ClinicalService (a nation-based data repository and medical care project) were analyzed. Patients were divided into two groups, those who underwent BPD after TAVI and those who did not. Coprimary endpoints were all-cause death and SVD. Cumulative incidence functions for SVD were estimated. Among 1835 patients included in the study, 417 (22.7%) underwent BPD and 1418 (77.3%) did not undergo BPD. No statistically significant differences at 6-year follow-up were found between groups in terms of all-cause mortality (HR: 1.05, 95% CI: 0.9-1.22; p = 0.557) and SVD (2.1% vs. 1.4%, p = 0.381). In addition, BPD did not predispose to higher risk of cardiovascular death, myocardial infarction, valve thrombosis, and endocarditis at 6-year follow-up. BPD following TAVI with a self-expanding prosthesis does not seem to be associated with an increased risk of adverse clinical outcomes or SVD at 6-year follow-up.

In silico model to assess thrombosis risk of TAVR with hemodynamic predictors using fluid structure interaction

Abstract The promising results of transcatheter aortic valve replacement (TAVR) over the past two decades indicate an expansion of the patient cohort toward patients with intermediate or low surgical risk. Since some complications of TAVR have already been minimized, subclinical leaflet thrombosis (SLT) has gained importance in recent years. SLT is manifested by a thrombotic layer on the prosthetic leaflets that gradually reduces leaflet motion. The resulting decrease in functionality of the TAVR causes a need for re-intervention. The origin of SLT and approaches to prevent SLT are still unexplored. For this reason, we have developed an in silicomodel that can be used during the design development process of TAVR devices to estimate the thrombosis risk of the implant. Based on passive scalar transport, hemodynamic metrics are used to quantify platelet activation and aggregation which are associated with the formation of thrombosis. In conjunction with a numerical simulation model considering the fluid-structure interaction between the blood mimicking fluid and the TAVR implanted in an aortic root, the thrombosis risk can be modeled. The simulation model can be used to calculate the three-dimensional flow structures within the native sinus and neo-sinus and also provides the ability to derive metrics to assess the risk of thrombosis. We demonstrated that this in silicomodel is a time-effective tool to assess thrombosis risk in TAVR product development.

Transventricular Cardioscopic Release of a Trapped Prosthetic Mitral Valve Leaflet.

Trapped prosthetic valve leaflets are a rare but challenging complication. A 68-year-old male patient had previously undergone redo aortic valve replacement. Postoperatively, he decompensated with severe mitral regurgitation, requiring extracorporeal membrane oxygenation and a salvage mitral valve replacement via right thoracotomy with very difficult access. This procedure was complicated by a trapped valve leaflet. He recovered well initially but presented 2 years later with worsening heart failure due to mitral stenosis and rising pulmonary artery pressures. Due to the high risk of sternotomy and right thoracotomy, a transventricular cardioscopic release of the trapped mitral valve leaflet was undertaken by left minithoracotomy. The procedure was successful, and the patient was discharged home on day 12. This novel minimally invasive approach, which does not require myocardial preservation, is ideal for high-risk patients with this rare complication and has not previously been described. We hope that by sharing our experience, others will consider this innovative approach.

IN SILICO MODELING OF PORCINE PERICARDIAL TISSUE LEAFLETS FOR TRANSCATHETER MITRAL VALVE REPLACEMENT

Tissue valve in combination with a mechanical valve is predominantly used in stented valvular prostheses. Porcine pericardium (PP) is a promising xenograft in addition to the predominately used porcine aortic valve (PAV) and bovine pericardium (BP) in heart valve replacement. Tissue valves are structurally similar to the valve cusps, upon fixation they function as structural and functional units to restore the failing heart valves. In this paper, the characterization, design and performance of PP based prosthetic mitral leaflets are analyzed. Uniaxial tensile test was performed to characterize glutaraldehyde (GA)-treated PP and evaluate its mechanical properties. Finite element methods were instrumental to design and analyze the performance of PP leaflets. Different geometric parameters were analyzed to obtain ideal valve performance. Since geometrical parameters influence valve performance, two leaflet models of trileaflet and quadrileaflet configuration were studied. BP and PAV leaflet models were designed and analyzed as controls to compare the performance of PP. The stress distribution, bending momentum and coaptation pattern from the finite element determine the performance of the geometrical models. PP exhibited anisotropy, promising tensile strength and pliability. A thinner porcine pericardium with promising tensile strength and pliability is ideal for the development of low-profile prosthetic valves. The quadrileaflet model exhibited.

P294 BIOPROSTHETIC AORTIC VALVE REPLACEMENT IN PATIENTS AT INCREASED RISK OF EARLY STRUCTURAL VALVE DEGENERATION

Abstract Background Biological prostheses are increasingly been used in young patients to avoid anticoagulation. The Edwards Inspiris aortic bioprosthesis is extremely promising in this population, since it has shown reduced calcification of the prosthetic leaflets in preclinical and early clinical studies. Little data are available, however, in patients younger than 65. This study investigates the hemodynamic performance and clinical outcome of the Inspiris bioprosthesis in patients aged 56 ± 10.7 years. Methods and Results Between may 2018 and December 2022, 342 patients aged 56 ± 10.7 years underwent AVR with the Edwards Inspiris bioprosthesis at our institution. 37 of them (10.8%) were younger than 40, and 98 (28.6%) had a BMI >30 kgm2. A minimally invasive approach was used in all isolated AVR patients. Associated procedures were performed in 157 (45.9%) patients. There were 56 redo patients (16.4%). 7 patients died (2%). Major complications included bleeding (32), respiratory failure (20) and BAV requiring PMK (4). The mean follow up was 23 ± 15.2 months (range 2–55). Late valve–related events included endocarditis (5) requiring reoperation. There were no thromboembolic events, valve thrombosis or SVD cases. At follow up, all except four patients reported a significant improvement of their symptomatic status (98.8% were in NYHA II) and quality of life. Conclusion Our study demonstrates excellent early haemodynamics and promising results at up to four years in a cohort of very young patients. Further studies with longer follow–up are needed.

P345 INTERMEDIATE–TERM RESULTS OF A NEW AORTIC BIOPROSTHESIS IN PATIENTS AT INCREASED RISK OF EARLY SVD

Abstract Background and aim Biological prosthesis are increasingly been used in young patients to avoid anticoagulation. The Edwards Inspiris aortic bioprosthesis is extremely promising in this population, since it has shown reduced calcification of the prosthetic leaflets in preclinical and early clinical studies. Little data are available, however, in patients younger than 65. This study investigates the haemodynamic performance and clinical outcome of the Inspiris bioprosthesis in patients aged < 50 years. Methods Between May 2018 and May 2022, 58 patients aged 41±7.8 years underwent AVR with the Edwards Inspiris bioprosthesis. Twenty–three (39.65%) were younger than 40, and 7 (12.06%) had a BMI >30 kgm2. A minimally invasive approach was used in all isolated AVR patients. Associated procedures were performed in 25 (43.10%) patients. There were 10 redo patients (17.2%). Results Major complications included bleeding (4), respiratory failure (1) and BAV requiring PMK (1). Two patients died (3.45%). The mean follow up was 29.6±12.3 months (range 10–51). Late valve–related events included endocarditis (2) requiring reoperation. There were no thromboembolic events, valve thrombosis or SVD cases. At follow up, all except one patient reported a significant improvement of their symptomatic status (96.29% were in NYHA II) and quality of life. The mean interval to return to the normal activity was of 5.37±3.3 months. Conclusion Our study demonstrates promising results at up to 4 years in a cohort of very young patients. Further studies with longer follow–up are needed.

P98 A CASE OF “RECURRENT” AORTIC VALVE STENOSIS

Abstract Clinical Case A 80–year–old man underwent coronary angiography in 2006 because of stable angina. There was chronic total occlusion of middle left anterior descending artery requiring percutaneous intervention. In 2009 he underwent coronary angiography for recurrent angina: a severe stent restenosis was treated with stenting in stent (DES in BMS). The patient was subsequently asymptomatic till 2018 when he complained of exertional dyspnea and angina. Stent patency and severe aortic valve stenosis (AVA 0.85 cm2) were documented. The patient underwent successful transcatheter aortic valve implantation and discharged with dual antiplatelet therapy (DAPT) (Asa 100 mg and Clopidogrel 75 mg). Clinical and echocardiographic follow–up was unremarkable (mean prosthetic gradient 17 mmHg, DVI=0.45). In July 2021 during a cardiological check the patient complained of bruising: ASA was discontinued. In February 2022 the patient suffered from an exertional angina. A dipyridamole stress–echocardiography failed to demonstrate inducible ischemia, although the patient experienced angina at the peak load step. Transthoracic echocardiogram (TTE) revealed high mean trans–prosthetic aortic gradient (52 mmHg, DVI=0.18). A trans–esophageal echocardiogram (TEE) showed reduced mobility of the thickened left coronary and non–coronary aortic prosthetic leaflets. In the hypothesis of prosthetic valve thrombosis, warfarin (INR range 2–3) was started after stopping clopidogrel. After three months a TTE showed normalized mean trans–prosthetic gradients (17 mmHg, DVI=0.5). When a 6 month–period of anticoagulant therapy was accomplished, warfarin was stopped and DAPT administered again. In September 2022 the patient complained of worsening dyspnea and chest pain on exertion. At TTE mean trans–prosthetic gradients (46 mmHg) was increased. A new TEE showed thickening of non–coronary and right coronary leaflets, suggestive of recurrent valve thrombosis. After stopping DAPT, warfarin was started again with good result (mean prosthetic gradient 12 mmHg, DVI=0.5). Conclusion Thrombosis of aortic valve prothesis is an infrequent event usually occurring in early post–implantation period. In our case it occurred four years after implantation following DAPT interruption. The likely initial prosthetic valve degeneration together with a simplification of DAPT may have had a causative role. Since the proved efficacy of warfarin and the limited experience of DOAC in this field, the patient was given warfarin sine die.

A Novel Approach to Diagnostic Left and Right Heart Catheterization in a Patient With a Mechanical Prosthetic Tricuspid Valve.

A 47-year-old patient was experiencing dyspnea and fatigue concerning for right ventricular hypertension and new heart failure. Because of the risks associated with catheter entrapment, prosthetic valve leaflet damage, and valve thrombosis associated with crossing a mechanical valve, a novel technique was used for diagnostic left and right heart catheterization in a patient with mechanical tricuspid valve replacement and tortuous pulmonary arteries. Using a percutaneous subxiphoid approach to avoid traversing the mechanical valve without discontinuing anticoagulation, a Volcano fractional flow reserve pressure wire (Philips Volcano) was advanced for distal measurements of pressures and saturations.

Fluid-structure interaction analysis of transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) is a minimally invasive intervention for the treatment of severe aortic valve stenosis. The main cause of failure is the structural deterioration of the implanted prosthetic leaflets, possibly inducing a valvular re-stenosis 5-10 years after the implantation. Based solely on pre-implantation data, the aim of this work is to identify fluid-dynamics and structural indices that may predict the possible valvular deterioration, in order to assist the clinicians in the decision-making phase and in the intervention design. Patient-specific, pre-implantation geometries of the aortic root, the ascending aorta, and the native valvular calcifications were reconstructed from computed tomography images. The stent of the prosthesis was modeled as a hollow cylinder and virtually implanted in the reconstructed domain. The fluid-structure interaction between the blood flow, the stent, and the residual native tissue surrounding the prosthesis was simulated by a computational solver with suitable boundary conditions. Hemodynamical and structural indicators were analyzed for five different patients that underwent TAVI - three with prosthetic valve degeneration and two without degeneration - and the comparison of the results showed a correlation between the leaflets' structural degeneration and the wall shear stress distribution on the proximal aortic wall. This investigation represents a first step towards computational predictive analysis of TAVI degeneration, based on pre-implantation data and without requiring additional peri-operative or follow-up information. Indeed, being able to identify patients more likely to experience degeneration after TAVI may help to schedule a patient-specific timing of follow-up.

460 BIOPROSTHESIS HEMODYNAMICS AND CORONARY FLOW AFTER TAVI IN TAVI

Abstract Background TAVI-in-TAVI is a complex intervention, potentially associated with feared complications such as coronary artery obstruction or Sinus of Valsalva (SOV)sequestration. Coronary obstruction risk is high when the degenerated bioprosthesis has supra-annular leaflets, the sinus of Valsalva is effaced, and/or sino-tubular Junction (STJ) is narrow. Clinical Case A 91 years old man, underwent TAVI with Acurate NEO M in 2016 with good results: post procedural mean gradient was 8mmHg and PVL was mild. He was admitted in our Institute after six years from index procedure for an episode of acute heart failure with echocardiogram findings of prolapse of one of the prosthetic leaflet causing severe aortic regurgitation without signs of active endocarditis. He was a potential candidate for transfemoral TAVI in TAVI and he had an intermediate risk score. The most important phase of this procedure was a careful planning through the preprocedural CTA. The potential maximal neoskirt of the Acurate M is 30mm. In this case, on one hand, we had wide SOV of 33mm of diameter and wide STJ of 30mm of diameter, on the other hand we had a left main ostia height of 15.5mm, a right coronary artery ostia height of 14mm and a STJ height of 25mm from the basal plane of the transcatheter heart valve (THV), hence we excluded THV with higher frame as Evolut or Acurate to prevent the formation of a long-covered stent of at least 23-24mm and 29-30mm respectively. In the trasversal annular plane obtained by multiplanar CT reconstruction we implanted a “virtual” valve at the geometric center simplified as a cylinder with a diameter of 23 mm to measure the valve to coronary (VTC) and valve to sino-tubular junction (VTSTJ) distance obtaining safe values of 5mm and 8mm respectively, both above the high risk threshold of 4mm for VTC and 2,5-3,5mm for VTSTJ. We chose a SAPIEN ULTRA 23mm for its short frame with a potential maximal neoskirt of 18mm and for its open cell strut to facilitate coronaries reaccess at the cost of a higher degree of first THV leaflets overhang. We decided to perform a low implant with more percentage of overhang THV but a low risk of coronaries flow impairment. Results Excellent result with correct positioning, coronaries patency and absence of leak. The selective cannulation of both coronaries was performed easily and successfully. The patient was discharged the next day with stable haemoglobin and a mean gradient of 8mmHg with no intraprosthetic aortic regurgitation. Conclusion In case of leaflets degeneration with preserved mobility, the low implantation a short frame THV could preserve the formation of the neoskirt above the top of its frame and determining an overhang of first THV leaflets without precluding acute and short-term hemodynamics Discussion In consideration of the expansion of TAVI indication even in younger patients we will encounter an increase of TAVI in TAVI procedures, therefore it is essential to familiarize with CTA reconstructions to assess the risk of direct or indirect coronary occlusion and to do the best THV choice according to the cause of the dysfunction and the anatomical features.

Computed tomography vs. cinefluoroscopy for the assessment of mechanical prosthetic valve leaflet motion.

Evaluation of mechanical prosthetic valve function is based on echocardiography, but adequate assessment of leaflet motion is limited by acoustic shadowing. Cinefluoroscopy is a standard method to assess leaflet motion, while computed tomography (CT) has been suggested as an alternative. We sought to compare the feasibility of leaflet motion assessment by cinefluoroscopy vs. CT. In 35 prospectively enrolled patients, leaflet motion was assessed in 43 bileaflet mechanical prostheses (29 mitral and 14 aortic) by cinefluoroscopy and non-contrast CT. Assessment was considered feasible when the 'in profile' projection (with the radiographic beam parallel to both the valve ring plane and the tilting axis of discs) could be achieved. Overall feasibility of fluoroscopic assessment was 74% (mitral, 66% vs. aortic, 93%; p = 0.071), while feasibility of CT assessment was 100% (p = 0.003). Among prostheses with unfeasible fluoroscopic assessment, CT suggested an extreme C-arm angulation to achieve the "in profile" projection (RAO: 76.0 ± 5.8°, LAO: 122.7 ± 32.5°, CRA: 51.4 ± 16.0°, CAU: 57.0 ± 18.2°). Among prostheses with feasible assessment by both techniques, fluoroscopy and CT yielded similar opening and closing angles (intraclass correlation coefficient, 0.959-0.998) with lower irradiation with CT as compared with fluoroscopy (26.2[21.1-29.3] vs. 289[179-358] mGy, p < 0.001). While CT scan took 8.7 ± 0.5s, fluoroscopy required 2.64 ± 1.56min to achieve and record the "in profile" projection. Non-contrast CT provides a higher feasibility and a quicker evaluation of mechanical prosthetic valve leaflet motion with less irradiation than fluoroscopy, especially in mitral valve position.

Validation of a Fluid Structure Interaction Model for TAVR using Particle Image Velocimetry

Abstract The implantation of a transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis improves pathologic blood flow through the aortic valve, but still alters hemodynamics in comparison to a healthy native aortic valve. The hemodynamic characteristics of TAVR are associated with hypo-attenuating leaflet thickening and prosthetic leaflet thrombosis, which may reduce the durability of TAVR. For this reason we developed a numerical model to identify pro-thrombotic regions of TAVR based on the velocity field. In silico models have already been proven to be an effective tool for device optimization in other medical device applications. However, when using an in silico model, it is important to validate the model assumptions with experimental data or analytical solutions to confirm the accuracy of the model. In this study, we present an approach to validate a complex numerical Fluid Structure Interaction (FSI) model used to simulate leaflet kinematics and flow in the vicinity of a TAVR. Based on the recommendation of ISO 5840 (2021), a combined validation of the kinematic and fluid dynamic parameters was performed for this purpose. The leaflet kinematic was investigated via high-speed recordings and evaluated based on the Geometric Orifice Area (GOA). The velocity field of the TAVR was determined experimentally using Particle Image Velocimetry (PIV). The evaluation of the GOA showed a good agreement of the in silico model with the in vitro data for the systolic duration. The occurring velocities were qualitatively compared during peak systole for three planes and showed similar flow characteristics. The maximum velocity was 1.1 m/s in the in vitro and in silico model. Based on the results, it can be assumed that the numerical FSI model of the TAVR can be used for thrombosis risk assessment.

Apixaban and Valve Thrombosis After Transcatheter Aortic Valve Replacement: The ATLANTIS-4D-CT Randomized Clinical Trial Substudy.

Subclinical obstructive valve thrombosis after transcatheter aortic valve replacement (TAVR) is of uncertain frequency and clinical impact. The aim of this study was to determine the effects of apixaban vs standard of care on post-TAVR valve thrombosis detected by 4-dimensional (4D) computed tomography. The randomized ATLANTIS (Anti-Thrombotic Strategy to Lower All Cardiovascular and Neurologic Ischemic and Hemorrhagic Events After Trans-Aortic Valve Implantation for Aortic Stenosis) trial demonstrated that apixaban 5mg twice daily was not superior to standard of care (vitamin K antagonists or antiplatelet therapy) after successful TAVR and was associated with similar safety but with more noncardiovascular deaths. Three months after randomization, 4D computed tomography was proposed to all patients to determine the percentage of patients with≥1 prosthetic valve leaflet with grade 3 or 4 reduced leaflet motion or grade 3 or 4 hypoattenuated leaflet thickening (the primary endpoint) in the intention-to-treat population. Seven hundred sixty-two participants had complete multiphase datasets and were included in the 4D computed tomographic analysis. The primary endpoint occurred in 33 (8.9%) and 51 (13.0%) patients in the apixaban and standard-of-care groups, respectively. It was reduced with apixaban vs antiplatelet therapy (OR: 0.51; 95%CI: 0.30-0.86) but not vs vitamin K antagonists (OR: 1.80; 95%CI: 0.62-5.25) (Pinteraction=0.037). The composite of death, myocardial infarction, any stroke, or systemic embolism at 1 year occurred in 10.7% (n=9 of 84) and 7.1% (n=48 of 178) of patients with and without subclinical valve thrombosis at 90days, respectively (HR: 1.68; 95%CI: 0.82-3.44). Apixaban reduced subclinical obstructive valve thrombosis in the majority of patients who underwent TAVR without having an established indication for anticoagulation. This study was not powered for clinical outcomes. (Anti-Thrombotic Strategy After Trans-Aortic Valve Implantation for Aortic Stenosis [ATLANTIS]; NCT02664649).

Non-contrast computed tomography versus cinefluoroscopy for the assessment of mechanical prosthetic valve leaflet motion

Introduction: valve replacement remains the definitive treatment of most cases with severe valvular heart disease. Mechanical prosthetic valves remain the main option in younger patients. Objective: evaluation of mechanical prosthetic valve function by comparing the feasibility of leaflet motion assessment by cinefluoroscopy vs. CT. Materials and methods: Leaflet motion was assessed in 30 bileaflet mechanical prostheses (21 mitral and 9 aortic) by cinefluoroscopy and non-contrast CT. Assessment was considered feasible when the ‘in profile’ projection (with the radiographic beam parallel to both the valve ring plane and the tilting axis of discs) could be achieved. Results: Overall feasibility of fluoroscopic assessment was 74% (mitral, 66% vs. aortic, 93%; p=0.071), while feasibility of CT assessment was 100% (p=0.003). Among prostheses with unfeasible fluoroscopic assessment, CT suggested an extreme C-arm angulation to achieve the “in profile” projection (RAO: 76.0±5.8°, LAO: 122.7±32.5°, CRA: 51.4±16.0°, CAU: 57.0±18.2°). Among prostheses with feasible assessment by both techniques, fluoroscopy and CT yielded similar opening and closing angles (intraclass correlation coefficient, 0.959 - 0.998) with lower irradiation with CT as compared with fluoroscopy (26.2[21.1-29.3] vs. 289[179-358] mGy, p&lt;0.001). While CT scan took 8.7±0.5 seconds, fluoroscopy required 2.64±1.56 minutes to achieve and record the “in profile” projection.

Efficacy and Safety of Postdilation for a Self-Expanding Transcatheter Heart Valve.

Data are lacking regarding the outcomes of balloon postdilation (BPD) for the Acurate neo and neo2 devices. The aim of this study was to assess the impact of BPD in a large, single-center cohort of patients treated with the Acurate platform. For this retrospective analysis, we included all patients with severe aortic stenosis who underwent transfemoral transcatheter aortic valve replacement (TAVR) with the Acurate neo or neo2 prosthesis at our institution. Among 1417 Acurate recipients, BPD was required in 521 cases (36.8%) for relevant paravalvular regurgitation (PVR) (n = 418) and incomplete prosthesis expansion or increased transprosthetic gradients (n = 103). Overall, BPD was successful in 87.9% and led to a significant reduction of more-than-mild PVR from 32.0% to 7.5% (P<.001). In the BPD group, prosthesis-patient mismatch (PPM) was less common. Prosthetic leaflet damage or valve dislodgment due to BPD occurred in 6 cases (1.2%). All other outcomes were similar between groups with and without BPD, including rates of aortic root injury, stroke, acute kidney injury, permanent pacemaker implantation, and all-cause 30-day mortality. Independent predictors of the need for BPD were higher mean transaortic gradients, severe aortic valve calcification, less prosthesis oversizing, and the use of larger prosthesis sizes. For transfemoral TAVR using the Acurate neo/neo2, BPD effectively reduces relevant PVR and decreases the risk of PPM without increasing adverse events. Transcatheter heart valve damage associated with BPD is rare, commonly avoidable, and does not jeopardize the net benefit of BPD.

P52 “BIOPROSTHETIC AORTIC VALVE REPLACEMENT IN PATIENTS YOUNGER THAN 49”

Abstract Background Biological prosthesis are increasingly been used in young patients to avoid anticoagulation. The Edwards Inspiris aortic bioprosthesis is extremely promising in this population, since it has shown reduced calcification of the prosthetic leaflets in preclinical and early clinical studies. Little data are available, however, in patients younger than 65. This study investigates the haemodynamic performance and clinical outcome of the Inspiris bioprosthesis in patients aged &amp;lt; 50 years. Methods and Results Between may 2018 and December 2021, 58 patients aged 41 +/– 7,85 years underwent AVR with the Edwards Inspiris bioprosthesis at our institution. 23 of them (39.65%) were younger than 40, and 7 (12.06%) had a BMI &amp;gt;30 kgm2. A minimally invasive approach was used in all isolated AVR patients. Associated procedures were performed in 25 (43.10%) patients. There were 10 redo patients (17,24%). Two patients died (3.45%). Major complications included bleeding (4), respiratory failure (1) and BAV requiring PMK (1). The mean follow up was 26,60 +/– 11,29 months (range 2–43). Late valve–related events included endocarditis (2) requiring reoperation. There were no thromboembolic events, valve thrombosis or SVD cases. At follow up, all except one patients reported a significant improvement of their symptomatic status (96.29% were in NYHA≤II) and quality of life. The mean interval to return to the normal activity was of 5.37±3.3 months. Conclusion Our study demonstrates excellent early haemodynamics and promising results at up to 3 years in a cohort of very young patients. Further studies with longer follow–up are needed

Valve-in-Valve Transcatheter Aortic Valve Replacement in a High-Risk Patient with a Biocor Bioprosthesis and a Flail Prosthetic Valve Leaflet

An 80-year-old woman with a history of surgical aortic valve replacement with a 21 mm St. Jude Medical Biocor porcine aortic valve 14 years prior presented with New York Heart Association (NYHA) class III symptoms, severe aortic insufficiency from a degenerated prosthesis, and a large echocardiographic mobile mass representing a highly mobile prosthetic leaflet. The patient worsened to NYHA class IV symptoms despite medical management. The Society of Thoracic Surgery mortality risk score was extremely high. However, a valve-in-valve transcatheter aortic valve replacement (TAVR) was found to be a reasonable option. We used a 20 mm SAPIEN 3 Ultra valve (Edwards Lifesciences Inc., Irvine, CA, USA) with a SENTINEL embolic protection device (Boston Scientific, Marlborough, MA, USA). During valve deployment, the echocardiographic mobile mass was visually pinned between the new TAVR valve and the surgical bioprosthetic valve. No large embolic debris was noted within the embolic protection device, and the patient remained without any new focal neurologic deficits in the perioperative period and at the 30-day follow-up. The severe aortic insufficiency resolved, and the patient clinically improved to NYHA class II symptoms.