Aortic Valve Engineering Advancements: Precision Tuning with Laser Sintering Additive Manufacturing of TPU/TPE Submillimeter Membranes.

Synthetic biomaterials play a crucial role in developing tissue-engineered heart valves (TEHVs) due to their versatile mechanical properties. Achieving the right balance between mechanical strength and manufacturability is essential. Thermoplastic polyurethanes (TPUs) and elastomers (TPEs) garner significant attention for TEHV applications due to their notable stability, fatigue resistance, and customizable properties such as shear strength and elasticity. This study explores the additive manufacturing technique of selective laser sintering (SLS) for TPUs and TPEs to optimize process parameters to balance flexibility and strength, mimicking aortic valve tissue properties. Additionally, it aims to assess the feasibility of printing aortic valve models with submillimeter membranes. The results demonstrate that the SLS-TPU/TPE technique can produce micrometric valve structures with soft shape memory properties, resembling aortic tissue in strength, flexibility, and fineness. These models show promise for surgical training and manipulation, display intriguing echogenicity properties, and can potentially be personalized to shape biocompatible valve substitutes.

Transcatheter correction of sinus venosus defect in a patient with a challenging anatomical configuration: From bench testing to clinical success.

We report successful transcatheter correction of a sinus venosus defect in a 72-year-old woman with anomalous pulmonary venous return in a challenging anatomical configuration. The procedure was facilitated by hands-on simulation training on a newly developed, perfused, 3D-printed model.

Transcatheter Closure of Superior Sinus Venosus Defects.

Superior sinus venosus defect is a communication between the right and left atrium located above the upper margin of the oval fossa, immediately inferior to the junction of the superior vena cava and the right atrium. It is systematically associated with partial anomalous pulmonary venous drainage, especially of the right upper pulmonary vein. Surgical repair has been the gold standard approach to close that defect. Introduced in 2014, percutaneous closure has gradually become a safe and effective alternative to surgery in carefully selected patients, although worldwide experience remains limited. This article provides an appraisal of the patients' selection process and a step-by-step description of the procedure as well as a comprehensive review of its outcomes.

Predictors of Clinical Success After Transcatheter Paravalvular Leak Closure: An International Prospective Multicenter Registry.

BACKGROUND: Transcatheter closure of a symptomatic prosthetic paravalvular leak (PVL) is feasible, but there is presently no conclusive evidence to show consistent efficacy. We aimed to identify predictors of clinical success after transcatheter PVL closure. METHODS: Consecutive patients referred to 24 European centers for transcatheter PVL closure in 2017 to 2019 were included in a prospective registry (Fermeture de Fuite ParaProthétique, FFPP). Clinical success was absence of any of the following within 1 month: re-admission for heart failure, blood transfusion, open-heart valvular surgery, and death. RESULTS: We included 216 symptomatic patients, who underwent 238 percutaneous PVL closure procedures on the mitral (64.3%), aortic (34.0%), or tricuspid (1.7%) valve. Symptoms were heart failure, hemolytic anemia, or both in 48.9%, 7.8%, and 43.3% of patients, respectively. One, 2, and 3 leaks were treated during the same procedure in 69.6%, 26.6%, and 3.8% of patients, respectively. The PVL was pinpoint or involved 1/8 or 1/4 of the valve circumference in 18.6%, 52.4%, and 28.1% of cases, respectively. The most frequently used devices were the Vascular Plug 3, Ventricular Septal Defect Occluder, Vascular Plug 2, and Paravalvular Leak Device (45.0%, 16.6%, 14.2%, and 13.6% of cases, respectively). Successful device(s) implantation with leak reduction to ≤grade 2 was obtained in 85.0% of mitral and 91.4% of aortic procedures, respectively (P=0.164); with major periprocedural adverse event rates of 3.3% and 1.2%, respectively (P=0.371); and clinical success rates of 70.3% and 88.0%, respectively (P=0.004). By multivariate analysis, technical failure, mechanical valve, and hemolytic anemia were independently associated with absence of clinical success (odds ratios [95% CIs], 7.7 [2.0-25.0]; P=0.002; 3.6 [1.1-11.1]; P=0.036; and 3.7 [1.2-11.9]; P=0.025; respectively). CONCLUSIONS: Transcatheter PVL closure is efficient and safe in symptomatic patients but is associated with a lower clinical success rate in patients with hemolysis and/or a mechanical valve. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifiers: NCT05089136.

3D-Printing to Plan Complex Transcatheter Paravalvular Leaks Closure.

BACKGROUND: Percutaneous closure of paravalvular leak (PVL) has emerged as an alternative to surgical management in selected cases. Achieving complete PVL occlusion, while respecting prosthesis function remains challenging. A multimodal imaging analysis of PVL morphology before and during the procedure is mandatory to select an appropriate device. We aim to explore the additional value of 3D printing in predicting device related adverse events including mechanical valve leaflet blockade, risk of device embolization and residual shunting. METHODS: From the FFPP registries (NCT05089136 and NCT05117359), we included 11 transcatheter PVL closure procedures from three centers for which 3D printed models were produced. Cardiac CT was used for segmentation for 3D printed models (3D-heartmodeling, Caissargues, France). Technology used a laser to fuse very fine powders (TPU Thermoplastic polyurethane) into a final part-laser sintering technology (SLS) with an adapted elasticity. A simulation on 3D printed model was performed using a set of occluders. RESULTS: PVLs were located around aortic prostheses in six cases, mitral prostheses in four cases and tricuspid ring in one case. The device chosen during the simulation on the 3D printed model matched the one implanted in eight cases. In the three other cases, a similar device type was chosen during the procedures but with a different size. A risk of prosthesis leaflet blockade was identified on 3D printed models in four cases. During the procedure, the occluder was removed before release in one case. In another case the device was successfully repositioned and released. In two patients, leaflet impingement was observed post-operatively and surgical device removal had to be performed. CONCLUSION: In a case-series of complex transcatheter PVL closure procedures, hands-on simulation testing on 3D printed models proved its usefulness to plan and facilitate these challenging procedures.

Complex transcatheter left atrial appendage closure using a tailored trans-jugular approach simulated by 3D printing: a case report.

Background: Transcatheter left atrial appendage (LAA) closure (LAAc) is less feasible in patients with unusual LAA anatomy. Case summary: A 65-year-old woman with persistent atrial fibrillation was referred for LAAc. Transesophageal echocardiography (TEE) revealed spontaneous contrast in the LAA without formation of a thrombus; the LAA shape was tortuous and difficult to assess. A first LAAc procedure was unsuccessful given the unsuitable sheath position. Therefore, a soft three-dimensional (3D) model printing was performed by laser sintering and revealed excessive sheath kinking with an inferior approach, but successful deployment would be feasible using a superior approach. Successful trans-jugular implantation of a Watchman FLX 31 device in stable position without residual leakage was achieved during the subsequent procedure. At 3-month follow-up, and after cessation of oral anticoagulation, the patient's symptoms improved. Imaging demonstrated complete LAA occlusion and correct placement of the device along the LAA superior axis. Discussion: This is the first-reported clinical case of a complex transcatheter LAAc through a trans-jugular approach. Simulating the patient's anatomy with a laser sintering 3D-printed model showed why the transfemoral approach failed, validated the trans-jugular procedure, enabled selection of the simple curve access sheath that had the most direct trajectory towards the LAA, confirmed that transseptal puncture was possible, allowed determination of the angle of puncture, enabled selection of the most appropriate LAA device and had a very low cost compared with planning software or other printing methods.

Prescription, Compliance, and Burden Associated with Salt-Restricted Diets in Heart Failure Patients: Results from the French National OFICSel Observatory.

(1) Background: There is much debate about the use of salt-restricted diet for managing heart failure (HF). Dietary guidelines are inconsistent and lack evidence. (2) Method: The OFICSel observatory collected data about adults hospitalised for HF. The data, collected using study-specific surveys, were used to describe HF management, including diets, from the cardiologists' and patients' perspectives. Cardiologists provided the patients' clinical, biological, echocardiography, and treatment data, while the patients provided dietary, medical history, sociodemographic, morphometric, quality of life, and burden data (burden scale in restricted diets (BIRD) questionnaire). The differences between the diet recommended by the cardiologist, understood by the patient, and the estimated salt intake (by the patient) and diet burden were assessed. (3) Results: Between March and June 2017, 300 cardiologists enrolled 2822 patients. Most patients (90%) were recommended diets with <6 g of salt/day. Mean daily salt consumption was 4.7 g (standard deviation (SD): 2.4). Only 33% of patients complied with their recommended diet, 34% over-complied, and 19% under-complied (14% unknown). Dietary restrictions in HF patients were associated with increased burden (mean BIRD score of 8.1/48 [SD: 8.8]). (4) Conclusion: Healthcare professionals do not always follow dietary recommendations, and their patients do not always understand and comply with diets recommended. Restrictive diets in HF patients are associated with increased burden. An evidence-based approach to developing and recommending HF-specific diets is required.

Role of cardiac imaging and three-dimensional printing in percutaneous appendage closure.

Atrial fibrillation is the most frequent cardiac arrhythmia, affecting up to 13% of people aged>80 years, and is responsible for 15-20% of all ischaemic strokes. Left atrial appendage occlusion devices have been developed as an alternative approach to reduce the risk of stroke in patients for whom oral anticoagulation is contraindicated. The procedure can be technically demanding, and obtaining a complete left atrial appendage occlusion can be challenging. These observations have emphasized the importance of preprocedural planning, to optimize the accuracy and safety of the procedure. In this setting, a multimodality imaging approach, including three-dimensional imaging, is often used for preoperative assessment and procedural guidance. These imaging modalities, including transoesophageal echocardiography and multislice computed tomography, allow acquisition of a three-dimensional dataset that improves understanding of the cardiac anatomy; dedicated postprocessing software integrated into the clinical workflow can be used to generate a stereolithography file, which can be printed in a rubber-like material, seeking to replicate the myocardial tissue characteristics and mechanical properties of the left atrial appendage wall. The role of multimodality imaging and 3D printing technology offers a new field for implantation simulation, which may have a major impact on physician training and technique optimization.

Multimodality imaging guidance for percutaneous paravalvular leak closure: Insights from the multi-centre FFPP register.

BACKGROUND: Percutaneous paravalvular leak (PVL) closure has emerged as a palliative alternative to surgical management in selected high-risk patients. Percutaneous procedures are challenging, especially for mitral PVL. Accurate imaging of the morphologies of the defects is mandatory, together with precise guidance in the catheterization laboratory to enhance success rates. AIMS: To describe imaging modalities used in clinical practice to guide percutaneous PVL closure and assess the potential of new imaging tools. METHODS: Data from the 'Fermeture de Fuite paraprothétique' (FFPP) register were used. The FFPP register is an international multi-institutional collaborative register started in 2017 with a retrospective and a prospective part. A descriptive analysis of multimodality imaging used to guide PVL closure in clinical practice was performed. RESULTS: Data from 173 procedures performed in 19 centres from three countries (France, Belgium and Poland) were collected, which included eight cases of PVL following transcatheter valve replacement. Transoesophageal echocardiography was used in 167 cases (96.5%) and 3D echocardiography in 87.4% of cases. In one case, 3D-echocardiography was fused with fluoroscopy images in real time using echonavigator software. Details about multimodality imaging were available from a sample of 31 patients. Cardiac computed tomography (CT) was performed before 10 of the procedures. In one case, fusion between preprocedural cardiac CT angiography data and fluoroscopy data was used. In two cases, a 3D model of the valve with PVL was printed. CONCLUSION: Echocardiography, particularly the 3D mode, is the cornerstone of PVL imaging. Other imaging modalities, such as cardiac CT and cardiac magnetic resonance imaging, may be of complementary interest. New techniques such as imaging fusion and printing may further facilitate the percutaneous approach of PVLs.

Left atrial appendage occlusion simulation based on three-dimensional printing: new insights into outcome and technique.

AIMS: The aim of this study was to assess the predictive value of simulation based on 3D-printed models before left atrial appendage occlusion (LAAO) for peri-device leaks (PDL) and the impact on procedural outcomes compared to conventional imaging. METHODS AND RESULTS: Seventy-six patients referred for LAAO with double disc device underwent construction of a 3D-printed LA model using flexible photopolymer resin. An implant simulation was performed retrospectively in Group 1 (55 patients), blinded to implanted device size, and prospectively in Group 2 (21 patients). In Group 1, an off-axis device position occurred in 14 patients (25%) and the incidence of PDL was 27% (15 patients); mismatch between model and device size was the best predictor (area under the curve 0.88, CI: 0.77-0.99). When using 3D simulation prospectively, mean prosthesis number per patient (1.05±0.21 vs. 1.20±0.52, p=0.04) and incidence of leaks (5% vs. 27%, p<0.01) were reduced compared to conventional imaging alone, as well as fluoroscopy time (19 mins [13.4-23] vs. 13.5 mins [11.1-15], p=0.012) and total fluoroscopy dose (7,291 [1,811-12,734] vs. 1,978 (1,548-4,800) mGy·cm2, p=0.029). CONCLUSIONS: 3D-printed patient-specific adaptive and flexible LA models improve LAAO double disc device sizing. This can potentially reduce procedure time and the number of prostheses employed per patient.

Predictive value for paravalvular regurgitation of 3-dimensional anatomic aortic annulus shape assessed by multidetector computed tomography post-transcatheter aortic valve replacement.

AIMS: Paravalvular regurgitation (PAR) remains a serious complication after trans-catheter aortic valve replacement (TAVR). Multidetector computed tomography (MDCT)-based measurements of the aortic basal virtual ring (BVR) are considered the gold standard for trans-catheter heart valve (THV) sizing. However, the real anatomic aortic annulus is a 3-dimensional structure. To compare measurement of 3D-anatomic annulus with BVR and secondly to assess independent predictive parameters that may impact on PAR > mild post-TAVR (PAR+). METHODS AND RESULTS: MDCT was performed in 92 patients before and after balloon or self-expandable TAVR. 3D-AA shape was obtained point by point following the semilunar attachment of aortic cusps (Osirix-MD 2.8.2). 3D-oversizing index (nominal THV area/3D-AA area - 1) × 100 was calculated as well as 2D-oversizing index using BVR area instead of 3D-AA area. PAR was quantified by planimetry of vena-contracta in transthoracic echocardiography short-axis view. Valvular calcium volume and annulus calcium area were measured using Hounsfield-intensity detection. ROC curves and logistic regression for PAR(+) were performed. BVR area overall underestimated 3D-AA area by 19 ± 9% (P< 0.001), significantly more in PAR(+) (26 ± 7%) vs. PAR(-) (17 ± 9%, P< 0.001). 3D-oversizing index had greater predictive value for PAR > mild (area under the curve, AUC = 0.88) with 88% sensibility (Se) and 82% specificity (Sp) than 2D-oversizing index (AUC = 0.68) with 84% Se, but only 41% Sp (P< 0.0001). Also, valvular calcium volume and annulus calcium area were less predictors for PAR > mild (AUC = 0.68, respectively, AUC = 0.75, P = 0.002). In a multivariate analysis, only 3D-oversizing index showed an independent value for PAR > mild (OR = 18.6, P< 0.001). CONCLUSION: Basal ring CT measurement significantly underestimated the real 3D-anatomic aortic annulus area. This may impact on THV sizing and PAR incidence. 3D-oversizing index is the most predictive factor for PAR > mild.

Modification of the Unipolar Atrial Electrogram as a Local Endpoint During Common Atrial Flutter Ablation.

INTRODUCTION: Complete elimination of the negative component of the unipolar atrial electrogram recently proved predictive of lesions transmurality. We prospectively assessed its relevance as a real-time local ablative endpoint for each individual lesion created across the cavotricuspid isthmus (CTI) in order to constitute a line of bidirectionnal block during common atrial flutter (AFL) ablation. METHODS AND RESULTS: Sixty-two consecutive patients underwent common AFL ablation following an electrophysiological approach guided by real-time electrogram modification analysis. In 31 patients (unipolar group), the local ablative endpoint was complete elimination of the negative component of the unipolar atrial electrogram, while the other 31 patients (control group) were treated following our standard approach based on the currently used local ablative endpoint defined by a ≥50% amplitude decrease of the bipolar atrial electrogram. Bidirectional block was achieved in all patients (mean age 67.9 ± 11.5 with 80.6% of men). Mean ablation time (164.3 ± 88.3 seconds vs 332.8 ± 151.5 seconds; P < 0.001) and mean energy delivery (7.5 ± 4.1 kJ vs 14.2 ± 6 kJ; P < 0.001) were significantly shorter in the unipolar group compared to the control group. No statistical differences were seen in procedure time (68.5 ± 22.6 min vs 77.5 ± 20.2 min; P = 0.10). CONCLUSION: Real-time unipolar electrogram modification is a relevant local endpoint during common AFL ablation and leads to a substantial reduction of ablation time and energy delivery compared to a standard ablative approach while displaying a similar short- and long-term success rate.

Unipolar signal modification as a guide for lesion creation during radiofrequency application in the left atrium: prospective study in humans in the setting of paroxysmal atrial fibrillation catheter ablation.

BACKGROUND: In patients treated for paroxysmal atrial fibrillation, the pulmonary vein (PV) reconnection rate is substantial and may be related to the lack of transmurality achievement while performing PV isolation (PVI). It has been experimentally demonstrated that positive unipolar atrial electrogram completion, when applying radiofrequency energy, was associated with transmural lesions. In this regard, we seek to determine whether the unipolar signal modification may be an appropriate end point for point-by-point radiofrequency application and find out whether it could improve the paroxysmal atrial fibrillation ablation results in humans. METHODS AND RESULTS: Fifty consecutive patients (61±8 years old, 41 men) with paroxysmal atrial fibrillation underwent PVI using Carto and Lasso. Each radiofrequency application lasted until development of a completely positive unipolar electrogram. Fifty patients (63±9 years old, 40 men), who previously underwent PVI following the standard approach of our institution, corresponded to the control group. All PVs were isolated in all patients of both groups. However, the procedural and ablation times were significantly lower in the unipolar group compared with those of the control group, whereas the PV reconnection rate, after 30 minutes of waiting time, was not significantly different. Overall, 21±4 months after 1 PVI session, the sinus rhythm maintenance rate without antiarrhythmic drugs was significantly higher (P=0.027) in the unipolar group (88%) compared with that of the control group (70%). CONCLUSIONS: Unipolar signal modification is a useful end point for radiofrequency energy delivery in patients with paroxysmal atrial fibrillation who undergo PVI and leads to a substantial midterm sinus rhythm maintenance rate.

Catheter ablation in selected patients with depressed left ventricular ejection fraction and persistent atrial fibrillation unresponsive to current cardioversion.

AIMS: In congestive heart failure (CHF) patients with persistent atrial fibrillation (AF), direct current cardioversion (DCC) may reveal participation of tachycardiamediated process to left ventricular (LV) dysfunction by restoring sinus rhythm (SR). However, if DCC fails to restore SR, patients' management remains challenging. The aim of the study was to assess the AF catheter ablation benefit in a selected group of CHF patients with LV ejection fraction (LVEF) <40% and persistent AF unresponsive to DCC, in whom a tachycardia-mediated process is thought to be predominant. METHODS AND RESULTS: Between January 2008 and September 2011, among 129 CHF patients with persistent AF referred to our institution, 34 (63.8 ± 9-year old, 24 men) presented AF refractory to DCC with an estimated high likelihood of tachycardia-mediated LV dysfunction according to a specific set of criteria. These 34 patients underwent stepwise AF ablation and were closely followed up. After a mean 1.9 AF ablation procedures per patient and 17.6 ± 7 months after the last procedure, all patients were in SR. The New York Heart Association class improved from 2.8 ± 0.3 to 1 ± 0.2 (P< 0.001) and the LVEF increased from 30.4 ± 6 to 54.6 ± 6% (P< 0.0001) after 3-6 months of SR, with a persistent benefit as long as the SR was maintained. CONCLUSION: Atrial fibrillation catheter ablation in selected CHF patients with persistent AF refractory to DCC and without any other evidence for secondary LV dysfunction leads to a substantial LVEF improvement in the majority of them. However, redo procedures are frequent in order to achieve mid-term SR maintenance.

Detecting aortic valve bicuspidy in patients with severe aortic valve stenosis: high diagnostic accuracy of colour Doppler transoesophageal echocardiography.

OBJECTIVES: The diagnostic accuracy of multiplane bi-dimensional transoesophageal echocardiography (TEE) in detecting aortic valve bicuspidy is good, but is less reliable when the leaflets are moderately or severely calcified. We hypothesized that systolic colour Doppler analysis might improve the accuracy of diagnosing aortic bicuspidy by TEE in patients with severe symptomatic aortic stenosis (AS). METHODS: Two colour Doppler images of a stenotic aortic valve were defined in a preliminary study using multiplane TEE. In type I, the valve opening had a linear, angular or 'hanger-like' configuration and in type II it was more star-like or 'stellar'. The accuracy of this classification in detecting bicuspidy was evaluated. Fifty-one patients (mean age 71 years (range 40-90 years); 52% male) with severe symptomatic AS (defined as aortic valve area ≤1 cm(2)), requiring surgical aortic valve replacement, were included in this prospective study. The surgical findings were compared with the echocardiographic data. RESULTS: The incidence of aortic bicuspidy was 43%. The presence of type I colour Doppler configuration was significantly higher for bicuspid than for tricuspid aortic valves (95.5 vs 3.5%, respectively; P < 0.001). Diagnostic accuracy in detecting bicuspidy was high (sensitivity 95.5%; specificity 96.5%; positive predictive value 95.5%). Intra- and inter-observer agreements were excellent (Kappa coefficient = 0.88 and 0.92, respectively). CONCLUSIONS: Aortic valve bicuspidy may be accurately diagnosed by colour Doppler valve analysis during TEE in patients with severe AS. Larger prospective studies are required to confirm our results.

Is it reasonable to treat all calcified stenotic aortic valves with a valved stent? Results from a human anatomic study in adults.

OBJECTIVES: This study was designed to study the behavior of a stent deployed inside human stenotic aortic valves. BACKGROUND: Endovascular valved stent (VS) implantation is a promising new therapy for patients with severe calcific aortic stenosis (AS). The precise characteristics of stent deployment in humans have been poorly studied so far. METHODS: Thirty-five patients with severe AS were included in the study. Sixteen patients (46%) had bicuspid aortic valves. A self-expandable stent specifically designed for VS implantation was deployed intraoperatively inside the aortic valve before surgical aortic valve replacement. RESULTS: In tricuspid aortic valves, the shape of stent deployment was circular, triangular, or elliptic in 68%, 21%, or 11%, respectively. Noncircular stent deployment was frequent in bicuspid aortic valves (the elliptic deployment being the rule [79%]), and stent underdeployment was constant. The incidence of gaps between the stent external surface and the aortic valve did not differ between tricuspid and bicuspid valves (58% vs. 43%; p = 0.49). Sharp calcific excrescences protruding inside the stent lumen were present in 3 cases (9%). Ex vivo study of a homemade VS confirmed that the regularity of the coaptation line of the leaflets was critically dependent on the presence or the absence of stent misdeployment. CONCLUSIONS: Stent misdeployment was constant in bicuspid valves and occurred in one-third of cases of tricuspid valves. Premature failure of implanted VS (secondary to valve distortion or traumatic injury to the leaflets by calcific excrescences) might be an important concern in the future.