Stented Valve Research Articles

Prosthesis-patient mismatch is associated with long-term mortality following surgical aortic valve replacement

Abstract Background Prosthesis-patient mismatch (PPM) refers to a situation where the indexed effective orifice area (iEOA) of an implanted prosthetic valve is too small relative to the patient's body size, resulting in hemodynamic compromise. Studies examining the long-term consequences of PPM after surgical aortic valve replacement (SAVR) have yielded conflicting results. Purpose To evaluate the impact of PPM on long-term outcomes in patients undergoing primary isolated SAVR. Methods All patients who underwent isolated first-time SAVR from 1990-2014 were included in this observational, single-center study. PPM was defined as a predicted iEOA <0.85 cm2/m2 and severe PPM was defined as an iEOA <0.65 cm2/m2. Patient demographics, surgical details, and in-hospital outcomes were prospectively collected in our institutional database. Cases were linked to provincial administrative databases at an independent, non-profit research institute whose legal status allows it to collect and analyze health care and demographic data. The primary outcome of interest was all-cause mortality. Secondary outcomes were aortic valve reoperation (surgical or transcatheter) and post-operative hospitalization for heart failure. Multivariable Cox regression analysis identified risk factors for long-term mortality. Kaplan-Meier curves were generated for long-term survival and cumulative incidence functions for aortic valve reoperation and heart failure hospitalization. Results A total of 1,798 patients were included (no PPM: 770 [43%]; moderate PPM: 943 [52%]; and severe PPM: 85 [5%]). Mean age was 64±13 years, and 750 (42%) were female. 451 (25%) patients received a mechanical valve, and 1347 (75%) received a stented bioprosthetic valve. Concomitant aortic root enlargement was performed in 492 (27%) patients. At 20 years, survival was 47.8% (95% CI: 43.2%–52.2%) in the "no PPM group" compared with 29.5% (95% CI: 25.6%–33.5%) and 24.7% (95% CI: 12.7%–38.8%) in the moderate and severe PPM groups, respectively (p<0.001) (Figure 1). On multivariable analysis, iEOA was independently associated with long-term mortality (HR 0.95 per 0.10 increase in iEOA, 95% CI [0.91–0.98]; p=0.007). In a pre-specified subgroup analysis, iEOA was found to be associated with late mortality in patients younger than 65 years (p<0.001) but not in patients 65 years and older (p=0.23). Readmission for heart failure was more frequent among patients who had PPM than those who did not (Figure 2). There was no difference in aortic valve reintervention in patients with or without PPM (p=0.654). Conclusions Prosthesis-patient mismatch is common after SAVR and is associated with late mortality and hospitalization for heart failure. The deleterious impact of PPM on survival appears more pronounced in young patients. These findings may have important implications for the lifetime management of patients with aortic valve disease.Survival post SAVRHeart failure hospitalization post SAVR

Investigation of mechanical performance for tricuspid valve stent in different compression modes

Abstract The tricuspid acting as a one-way valve between the right atrium and the right ventricle of the human heart, is very important for the blood circulation system. The regurgitation will be induced if the tricuspid cannot close normally, leading to symptoms such as arrhythmia and right heart failure. In the case of severe regurgitation, replacement with an artificial tricuspid valve instead of the natural tricuspid is the promising solution. For the typical artificial tricuspid valve, the bioprosthesis valve is fixed on a tricuspid valve stent which is usually compressed before being implanted into the heart. In this study, numerical simulation with an ABAQUS standard approach is carried out with a focus on the compression process of the tricuspid valve stent to evaluate the mechanical performances of two compression methods: one is the traditional radial compression method (RCM), and another is the axial compression method (ACM) that gradually compresses through a conical channel. The results indicate that the environment temperature is closely related to the stress distribution for both the RCM and ACM, in particular, a lower temperature can result in lower stress. The maximum strain is located at the inner corner of the joint of the stent ribs and the connection between the top arm and the stent, with a value over 12% at the temperature of 0°C, indicating the possible position for failure. The average diameter-stress curves of the RCM and ACM are respectively obtained for the compression process. To achieve long operation time, the RCM is recommended from the perspective of reducing compressive stress. The present study can provide the experience for the production and clinical application of tricuspid valve stents.

Mechanics guided design of programmable bilayer for aortic valve stent

Transcatheter aortic valve replacement (TAVR) has emerged as a promising treatment option for aortic stenosis. However, the prevalent stent used for valve placement restricts the post-release adjustment or movement of the artificial valve, increasing the potential risk to patients once accidental mispositioning occurs. Herein, we propose a 4D printing strategy to realize a proof-of-concept thermal-activated transcatheter aortic valve (TAV) stent that allows for programmable manipulation. Polylactic acid/polyurethane composites are directly printed to perform as the active units that tailor the configuration of the programmable TAV stent, accommodating to different tasks such as blood vessel navigation and topological fixation with cardiac cavity. A theoretical model is developed to explore the curvature evolutions of the active composite, realizing good agreement with experimental observations. Guided by the model, we seek out the optimized programming and activation conditions that allow for desired transformations to realize permanent fixation under intra-annular release and thermal-activated retraction under infra-annular release, inspiring the future development of TAV stents with shape memory principle.

Rupture of a calcified right ventricle to pulmonary artery homograft by balloon dilation– emergency rescue by venus P-Valve

BackgroundPercutaneous pulmonary valve implantation (PPVI) is a recognized alternative treatment to surgery for patients with dysfunctional right ventricular outflow tracts. Patient selection is essential to avoid serious complications from attempted treatment, such as rupture or dissection, especially of the calcified outflow tracts. We describe a case with an unexpected rupture of a calcified homograft valve and main pulmonary artery, which was treated successfully by emergency implantation of a self-expanding Venus P-Valve (Venus MedTech, Hangzhou, China) without the need for pre-stenting with a covered stent.Case detailsA 13-year-old boy had two previous operations of tetralogy of Fallot, one a total repair and the other a homograft valved conduit for pulmonary regurgitation. He presented with dyspnea and severe right ventricular outflow tract obstruction (RVOTO) and had a calcified outflow tract and main pulmonary artery. In the catheter laboratory, a non-compliant balloon dilation resulted in a contained rupture of the conduit. The patient remained hemodynamically stable, and the rupture was treated with a self-expandable Venus P-Valve without the need for a covered stent combined with a balloon-expandable valve or a further surgical procedure.DiscussionPreprocedural evaluation with an inflating balloon is necessary to examine tissue compliance and determine suitability for PPVI. However, this condition is accompanied by a risk of conduit rupture. Risk factors of this complication are calcification and homograft use. These ruptures are mostly controlled with a prophylactic or therapeutic covered stent, with a low rate of requiring surgery. However, there are severe ruptures which lead to hemothorax and death. In the available literature, there was no similar reported case of conduit rupture, which a self-expandable Pulmonary valve stent has managed. It seems that fibrosis and collagen tissue around the heart, formed after open surgeries, can contribute to the control of bleeding in these cases.Conclusion (clinical Learning Point)The suitability of patients for the PPVI procedure should be examined more carefully, specifically patients with homograft and calcification in their conduit. Furthermore, conduit rupture might be manageable with self-expandable artificial pulmonary valves, specifically in previously operated patients, and the applicability of this hypothesis is worth examining in future research.

Multicenter, propensity-weighted comparison of stented, rapid-deployment and new-generation aortic valves

BackgroundConventional stented, rapid deployment and new-generation stented valves are now available for surgical aortic valve replacement (SAVR). New-generation devices feature advanced tissue treatment for theoretical prolonged durability and a new stent design able to expand in case of future transcatheter Valve-in-Valve. Aim of this retrospective, multicenter, propensity-weighted study was to compare early clinical and hemodynamic outcomes of these three different bioprostheses. MethodsWe analyzed data of 2589 patients from two national multicenter registries and one Institutional database. Study devices were Magna Ease, Intuity/Intuity Elite and Inspiris Resilia (Edwards Lifesciences, Irvine, CA, USA) and were implanted in 296 (11.4 %), 1688 (65.2 %) and 605 (23.4 %) patients, respectively. A propensity score weighting approach was employed. ResultsIn isolated SAVR, aortic cross clamp (ACC) time was shorter for Intuity (Magna Ease: 87, Intuity: 55, Inspiris: 70 min; Magna Ease vs. Intuity: p < 0.001; Inspiris vs. Intuity: p < 0.001). Overall mortality was 2 %, 1.7 % and 0.5 % in Magna Ease, Intuity and Inspiris groups, respectively (Magna Ease vs. Intuity: p = 0.476; Inspiris vs. Intuity: p = 0.395); permanent pace-maker implantation rate was lower for Inspiris (Magna Ease: 6 %, Intuity: 6 %, Inspiris: 2 %; Magna Ease vs. Intuity: p = 0.679; Inspiris vs. Intuity: p < 0.001). Median mean gradients were 13, 10 and 10 mmHg for Magna Ease, Intuity and Inspiris, respectively (Magna Ease vs. Intuity: p < 0.001; Inspiris vs. Intuity: p = 0.13). ConclusionsAll study devices provide excellent early clinical and hemodynamic outcomes. Inspiris shows low rates of permanent pace-maker implantation and its transaortic gradients are similar to rapid-deployment valves and lower than Magna Ease.

Force Analysis Using Self-Expandable Valve Fluoroscopic Imaging: a way Through Artificial Intelligence.

This study aimed to develop a force analysis model correlating fluoroscopic images of self-expandable valves with stress distribution. For this purpose, a nonmetallic measuring device designed to apply diverse forces at specific positions on a valve stent while simultaneously measuring force magnitude was manufactured, obtaining 465 sets of fluorescent films under different force conditions, resulting in 5580 images and their corresponding force tables. Using the XrayGLM, a mechanical analysis model based on valve fluorescence images was trained. The accuracy of the image force analysis using this model was approximately 70% (50-88.3%), with a relative accuracy of 93.3% (75-100%). This confirms that fluoroscopic images of transcatheter aortic valve replacement (TAVR) valve stents contain a wealth of mechanical information, and machine learning can be used to train models to recognize the relationship between stent images and force distribution, enhancing the understanding of TAVR complications.

Multidetector computed tomography imaging planning for bronchoscopy stent and valve placement in the treatment of COPD, air leaks, and airway stenosis

Bronchoscopy using a flexible bronchoscope is considered a safe procedure and has been used for diagnosing and treating airway and parenchymal lung diseases. Bronchoscopic interventions in selected patients with emphysema, airway stenosis, and air leaks provide new treatment options. The application of multidetector computed tomography (MDCT) planning prior to bronchoscopy is comprehensively addressed. Using MDCT scan for pre-procedural planning, ensures precise navigation and device placement during bronchoscopy, ultimately improving patient outcomes. Radiological features can be correlated with bronchoscopy findings, linking MDCT images with direct bronchoscopy observations.This educational statement provides a comprehensive overview of the integration of computed tomography and bronchoscopy in managing different pulmonary conditions treated with endobronchial valve and airway stent placement, focusing on key aspects to enhance understanding and application in clinical practice. Emphasis is placed on their role in treating airway stenosis (AS), air leaks, and chronic obstructive pulmonary disease (COPD), highlighting the conditions under which these procedures are most beneficial. It explores how MDCT imaging contributes to the diagnosis and treatment planning of these conditions and the correct interpretation of MDCT image findings during follow-up after the procedure.

Melody transcatheter pulmonary valve replacement: a single-center case series in Southeast Asia

BackgroundStudies of transcatheter pulmonary valve replacement (TPVR) with the Melody valve have demonstrated good clinical and hemodynamic outcomes. Our study analyzes the midterm clinical and hemodynamic outcomes for patients who underwent Melody valve implantation in Southeast Asia.MethodsPatients with circumferential conduits or bioprosthetic valves and experiencing post-operative right ventricular outflow tract (RVOT) dysfunction were recruited for Melody TPVR.ResultsOur cohort (n = 14) was evenly divided between pediatric and adult patients. The median age was 19 years (8–38 years), a male-to-female ratio of 6:1 with a median follow-up period of 48 months (16–79 months), and the smallest patient was an 8-year-old boy weighing 18 kg. All TPVR procedures were uneventful and successful with no immediate mortality or conduit rupture. The primary implant indication was combined stenosis and regurgitation. The average conduit diameter was 21 ± 2.3 mm. Concomitant pre-stenting was done in 71.4% of the patients without Melody valve stent fractures (MSFs). Implanted valve size included 22-mm (64.3%), 20-mm (14.3%), and 18-mm (21.4%). After TPVR, the mean gradient across the RVOT was significantly reduced from 41 mmHg (10–48 mmHg) to 16 mmHg (6–35 mmHg) at discharge, p < 0.01. Late follow-up infective endocarditis (IE) was diagnosed in 2 patients (14.3%). Overall freedom from IE was 86% at 79 months follow-up. Three patients (21.4%) developed progressive RVOT gradients.ConclusionFor patients in Southeast Asia with RVOT dysfunction, Melody TPVR outcomes are similar to those reported for patients in the US in terms of hemodynamic and clinical improvements. A pre-stenting strategy was adopted and no MSFs were observed. Post-implantation residual stenosis and progressive stenosis of the RVOT require long term monitoring and reintervention. Lastly, IE remained a concern despite vigorous prevention and peri-procedural bacterial endocarditis prophylaxis.

Modeling of valve-in-valve transcatheter aortic valve implantation after aortic root replacement using a 3-dimensional artificial intelligence algorithm

ObjectiveAortic root replacement requires construction of a composite valve-graft and reimplantation of coronary arteries. This study assessed the feasibility of valve-in-valve transcatheter aortic valve implantation after aortic root replacement. MethodsA retrospective review was conducted on 74 consecutive patients who received a composite valve-graft at a single institution from 2019 to 2021. Forty patients had bioprosthetic valves with adequate postoperative gated computed tomographic angiography scans. Computational simulations of balloon and self-expanding transcatheter valve deployments were performed. The modeled coronary distances were compared with traditional, manually measured valve-to-coronary distances. ResultsThere was a statistically significant difference in the modeled versus manual measurements of valve to coronary distances for all patients regardless of valve type or coronary artery analyzed (P < .05). Most patients are low risk for coronary obstruction per 3-dimensional modeling, including those with a valve-to-coronary distance <4 mm. Only 1 patient (2.5%) was at risk for coronary obstruction for the left coronary artery using a balloon valve. No other valve combination was considered high risk of coronary obstruction. Five patients (12.5%) were at risk for possible valve stent deformation at the outflow, due to angulation at the graft anastomosis. ConclusionsFollowing aortic root replacement, all patients were candidates for valve-in-valve procedure using 1 or both types of transcatheter heart valves. Self-expanding valves may be at higher risk for stent frame deformation at graft anastomotic lines and balloon-expandable valves may be at higher risk of coronary obstruction.

Mechanical Analysis of the Connection Structure of a Double-Layered Valve Stent within an Annuloplasty Ring

Background: In this study, to address the failure of mitral valve repair surgery, a novel valve-in-ring model for an artificial mitral valve annuloplasty ring and a new double-layer mitral valve were established. A suitable number and length of ventricular fixation struts within the annuloplasty ring, as well as the implantation depth, result in variations in stress and strain for the inner and outer stent layers. Methods: The compression and self-expansion model of the stent was established via finite element analysis. The changes in stress and strain were analyzed by setting the length and number of the ventricular fixed struts and implantation depth. Results: When only affected by factors such as blood pressure, the maximum stresses of stent structures with three and six ventricular fixed struts are 476 and 222 MPa, respectively, in the right posterior annular region. At implantation depths of 0, 0.5, 1, and 2 mm, the maximum stresses are located in the left posterior annular region of the outer stent and are 740, 697, 709, and 742 MPa, respectively, and the maximum displacements of the inner stent are all in the right posterior ventricular fixed strut region of the posterior annulus and are 3.71, 3.10, 2.48, and 1.87 mm, respectively. In the three and six ventricular fixed strut stents, when the ventricular fixed strut length is 3, 4, and 5 mm, the maximum stresses are 570, 557, and 621 MPa and 674, 666, 644 MPa, respectively. Conclusions: Appropriately increasing the number of ventricular fixed struts can effectively reduce damage to the stent inside the body, and the damage to the stent is relatively consistent across different implantation depths; however, the right side of the stent's posterior annulus is particularly susceptible to damage. However, if the implantation depth is lower, the impact on the inner stent will be more significant. As the number of ventricular fixed struts increases, the strut length variation has a relatively stable impact on stent damage.

Research Progress of Transcatheter Aortic Valve Replacement in Aortic Valve Stenosis due to Bicuspid Aortic Valve

Patients with bicuspid stenosis often have anatomical characteristics such as elliptical valve rings, high and asymmetric valve calcification, unequal valve leaflets, and concomitant widening of the ascending aorta and/or transverse heart. These unfavorable factors are more likely to cause poor placement of transcatheter aortic valve replacement (TAVR) valves, poor expansion of valve stents, which can lead to reduced valve durability, residual perivalve leakage, rupture of valve rings and surrounding structures, and serious surgical related complications such as ascending aortic dissection. In summary, TAVR treatment for mitral stenosis is receiving increasing attention. In this manuscript, we reviewed the research progress of transcatheter aortic valve replacement in aortic valve stenosis due to bicuspid aortic valve.

Thrombocytopenia after sutureless and standard stented aortic valve replacement: a retrospective analysis of risk factors, clinical course, and early outcome

ObjectivesThrombocytopenia following Perceval aortic valve replacement has been described previously with variable outcome. Studies have lacked a robust analysis of platelet fluctuation and factors affecting it. We aimed to statistically describe the trend in thrombocyte variability as compared with conventional aortic valve replacement, and to assess predictors as well as impact on associated outcomes.MethodsOne hundred consecutive patients with first-time Perceval were retrospectively compared to 219 patients after Perimount Magna Ease valve replacement. The primary outcome was the serial thrombocyte count on day 0–6. Generalized estimating equations were used to analyse the data using fixed-effect models: for the effect of the post-operative day on platelet count, and random-effect models estimating both time-variant (platelets) and time in-variant variables (valve type, age, LV function, pre-op platelet level).ResultsPerceval patients were older (72 ± 1 vs 68 ± 1 years, p < 0.01) with higher NYHA status (3(2–3) vs 2(1–2), p < 0.001). Mean platelet count in the sutureless group was lowest on day 2 (91.9 ± 31.6 vs 121.7 ± 53.8 × 103 µl−1), and lower on day 4 (97.9 ± 44) and 6 (110.6 ± 61) compared to the conventional group (157.2 ± 60 and 181.7 ± 79) but did not result in a higher number of transfusions, bleeding or longer hospital stay (p > 0.05). Reduced platelet count was a strong predictor of red cell transfusion in the conventional (p = 0.016), but not in the sutureless group (p = 0.457). Age (Coef -1.025, 95%CI-1.649—-0.401, p < 0.001) and CPB-time (Coef 0.186, 95%CI-0.371—-0.001, p = 0.048) were predictors for lower platelet levels.ConclusionConsidering the older patient profile treated with Perceval, postoperative thrombocytopenia does not impact on outcome in terms of transfusions, complications or hospital stay.

Mechanical behaviors of a new elliptical valve stent in bicuspid aortic valve

Background and ObjectiveThe conventional valve stents that are cylindrical in shape will become elliptical when implanted in bicuspid aortic valve, thereby reducing the durability of the artificial valve. In this study, a new design of valve stent is presented where valve stents have elliptical cross-section at the annulus and it is expected to have better expandability and circle shape during the interaction between the stent and bicuspid aortic valve, thereby extending the durability of artificial valve. MethodsFinite element method (FEM) is used to study the mechanical behavior of the novel valve stent in the bicuspid aortic valve. The effects of three matching relationship between the ellipticity of the stents and the ellipticity of the annulus (i.e., the ellipticity of the stent is greater than, equal to and less than the annulus ellipticity, respectively) on the mechanical behavior of stent expansion are studied. In addition, the expansion mechanical behavior of the novel valve stent at different implantation depths is also compared. ResultsResults indicate that novel valve stent implantation with elliptical features is superior to conventional circular valve stent. When the novel valve stent ellipticity is less than the annulus ellipticity, the ellipticity of the novel valve stent after implantation is smaller than that of the conventional circular valve stent. This indicated that the novel valve stent has better expandability and post-expansion shape, making artificial valve to have better durability. The risk of paravalvular leak after implantation is lowest when the novel valve stent ellipticity is less than annulus ellipticity. When the novel valve stent ellipticity coincides with annulus ellipticity, the aortic wall is subjected to greatest stress. With the increase of implantation depth, the stress on the novel valve stent decrease. ConclusionsThis study might provide insights for improving stent design for bicuspid aortic valve.

Finite element modeling with patient-specific geometry to assess clinical risks of percutaneous pulmonary valve implantation.

Percutaneous pulmonary valve implantation (PPVI) is a non-surgical treatment for right ventricular outflow tract (RVOT) dysfunction. During PPVI, a stented valve, delivered via catheter, replaces the dysfunctional pulmonary valve. Stent oversizing allows valve anchoring within the RVOT, but overexpansion can intrude on the surrounding structures. Potentially dangerous outcomes include aortic valve insufficiency (AVI) from aortic root (AR) distortion and myocardial ischemia from coronary artery (CA) compression. Currently, risks are evaluated via balloon angioplasty/sizing before stent deployment. Patient-specific finite element (FE) analysis frameworks can improve pre-procedural risk assessment, but current methods require hundreds of hours of high-performance computation. We created a simplified method to simulate the procedure using patient-specific FE models for accurate, efficient pre-procedural PPVI (using balloon expandable valves) risk assessment. The methodology was tested by retrospectively evaluating the clinical outcome of 12 PPVI candidates. Of 12 patients (median age 14.5 years) with dysfunctional RVOT, 7 had native RVOT and 5 had RV-PA conduits. Seven patients had undergone successful RVOT stent/valve placement, three had significant AVI on balloon testing, one had left CA compression, and one had both AVI and left CA compression. A model-calculated change of more than 20% in lumen diameter of the AR or coronary arteries correctly predicted aortic valve sufficiency and/or CA compression in all the patients. Agreement between FE results and clinical outcomes is excellent. Additionally, these models run in 2-6 min on a desktop computer, demonstrating potential use of FE analysis for pre-procedural risk assessment of PPVI in a clinically relevant timeframe.

Continuous or interrupted pledgeted suture technique in stented bioprosthetic aortic valve replacement: a comparison of in-hospital outcomes

BackgroundThere is ambiguity in the literature regarding the continuous suture technique (CST) for aortic valve replacement (AVR). At our center, there has been a gradual shift towards CST over the interrupted pledgeted technique (IPT). This study aims at comparing outcomes for both techniques.MethodsWe performed a retrospective analysis of a single-center study of patients undergoing AVR between January 2011 and July 2020. Patients were divided into two groups: Continuous suture technique and interrupted pledget-reinforced sutures. The pre-operative and In-hospital clinical characteristics and echocardiographic hemodynamics (i.e. transvalvular gradients and paravalvular leakage) were compared between CST and IPT.ResultsWe compared 791 patients with CST to 568 patients with IPT (median age: 73 and 74 years, respectively, p = 0.02). In CST there were 35% concomitant procedure vs. 31% in IPT (p = 0.16). Early mortality was 3.2% in CST versus 4.8% in IPT (p = 0.15), and a second cross-clamp due to a paravalvular-leak in 0.5% vs. 1.2%, respectively (p = 0.22). The CST was not associated with new-onset conduction-blocks mandating pacemaker implants(OR 1.07, 95% CI 0.54–2.14; P = 0.85). The postoperative gradients on echocardiography were lower in CST compared to IPT, especially in smaller annuli (peak gradients: 15.7mmHg vs. 20.5mmHg, in valve size < 23 mm, p < 0.001).ConclusionsThe continuous suture technique was associated with lower postoperative gradients and shorter cross-clamp time compared to interrupted pledgeted technique. Differences in paravalvular leaks were non-significant, although slightly less in the continuous suture technique. There were no further differences in valve-related complications. Hence, continues suture technique is safe, with better hemodynamics compared to the interrupted pledgeted technique. This may be of clinical importance, especially in smaller size annular size.

The Northern New England Rapid Deployment Valve Experience: Survival and Procedural Outcomes From 2015 to 2021.

The optimal approach and choice of initial aortic valve replacement (AVR) is evolving in the growing era of transcatheter AVR. Further survival and hemodynamic data are needed to compare the emerging role of rapid deployment (rdAVR) versus stented (sAVR) valve options for AVR. The Northern New England Cardiovascular Database was queried for patients undergoing either isolated AVR or AVR + coronary artery bypass grafting (CABG) with rdAVR or sAVR aortic valves between 2015 and 2021. Exclusion criteria included endocarditis, mechanical valves, dissection, emergency case status, and prior sternotomy. This resulted in a cohort including 1,616 sAVR and 538 rdAVR cases. After propensity weighting, procedural characteristics, hemodynamic variables, and survival outcomes were examined. The breakdown of the overall cohort (2,154) included 1,164 isolated AVR (222 rdAVR, 942 sAVR) and 990 AVR + CABG (316 rdAVR, 674 sAVR). After inverse propensity weighting, cohorts were well matched, notable only for more patients <50 years in the sAVR group (4.0% vs 1.9%, standardized mean difference [SMD] = -0.12). Cross-clamp (89 vs 64 min, SMD = -0.71) and cardiopulmonary bypass (121 vs 91 min, SMD = -0.68) times were considerably longer for sAVR versus rdAVR. Immediate postreplacement aortic gradient decreased with larger valve size but did not differ significantly between comparable sAVR and rdAVR valve sizes or overall (6.5 vs 6.7 mm Hg, SMD = 0.09). Implanted rdAVR tended to be larger with 51% either size L or XL versus 37.4% of sAVR ≥25 mm. Despite a temporal decrease in pacemaker rate within the rdAVR cohort, the overall pacemaker frequency was less in sAVR versus rdAVR (4.4% vs 7.4%, SMD = 0.12), and significantly higher rates were seen in size L (10.3% vs 3.7%, P < 0.002) and XL (15% vs 5.6%, P < 0.004) rdAVR versus sAVR. No significant difference in major adverse cardiac events (4.6% vs 4.6%, SMD = 0.01), 30-day survival (1.5% vs 2.6%, SMD = 0.08), or long-term survival out to 4 years were seen between sAVR and rdAVR. Rapid deployment valves offer a safe alternative to sAVR with significantly decreased cross-clamp and cardiopulmonary bypass times. Despite larger implantation sizes, we did not appreciate a comparative difference in immediate postoperative gradients, and although pacemaker rates are improving, they remain higher in rdAVR compared with sAVR. Longer-term hemodynamic and survival follow-up are needed.

Long-Term Results After Aortic Valve Replacement with Last-Generation Stentless Prostheses.

The purpose of this study was to evaluate the long-term clinical and hemodynamic results in patients affected by severe aortic valve disease after aortic valve replacement with third-generation stentless aortic prostheses (3F® stentless equine pericardial [Medtronic plc, Minneapolis Minnesota] and Pericarbon Freedom™ stentless bovine pericardial [LivaNova plc, London, United Kingdom]) and to analyze the benefits and the drawbacks associated to their use. Between June, 2003 and Sept, 2015 a cohort of 548 consecutive patients affected by aortic valve disease received an aortic valve replacement using a last-generation stentless pericardial aortic prosthesis at our unit. Respectively, 322 patients received a Pericarbon Freedom™ and 226 received a 3F® aortic valve. Size ranged between 19 and 29, with prevalence of 23 and 25 devices. Mean age at operation was 71± 11 years, 57% of patients were males, the mean logistic EuroScore was 8.9 ± 7.2 and 44.2% received concomitant procedures. The mean extracorporeal circulation (ECC) time was 119.2 ± 40.6. The mean cross clamp time was 90.5' ± 21.4'. In 30 patients, the aortic prosthesis was included in a Dacron tube straight graft for a Bentall operation. Early/in-hospital mortality was 2.55% (14 cases) for the entire cohort. In patients receiving isolated aortic valve replacement (AVR), it was 0.91% (5 cases). Follow up ranged between six months and 12 years (median follow-up time: 6.77 years). During follow up, 137 patients died of all causes (25%), of whom 32 patients died of cardiac causes (5.8%). Cardiac survival probability was 91% at 12 years. All surviving patients were in NYHA class I at last follow up. Actuarial freedom from structural valve deterioration was 86% at 12 years. Freedom from endocarditis was 95% at 12 years. Freedom from a valve-related reoperation at 12 years follow up was 95%. Mean residual transprosthetic gradient at 12 years was 10.3 ± 4.8MmHg. Last-generation stentless pericardial valves offer excellent hemodynamics and adequate durability and freedom from structural deterioration at 12 years follow up. The implantation technique of a stentless valve is a little more demanding when compared to a stented valve, but it can be easily reproduced after minimal training. Incidence of endocarditis and thromboembolic events is low and comparable to stented pericardial valves. Young and active patients, and patients with large BSA where a patient-prosthesis mismatch may be anticipated are, in our opinion, ideal candidates to receive these kinds of valves.

Feasibility study of using low-kilovoltage, prospective gating, high-pitch, dual-source computed tomography prior to transcatheter aortic valve replacement: analysis of image quality and radiation dose.

Computed tomography (CT) scans before transcatheter aortic valve replacement (TAVR) are used to evaluate the aortic valve and guide the selection of appropriate valve stents. Accurate imaging evaluation can ensure the success rate of surgery while reducing the incidence of complications. Multiple studies have adopted a protocol of coronary artery, aortic valve, and total aortic scan, with the patients receiving higher radiation doses. The aim of this study was to evaluate the image quality, radiation dose, and diagnostic performance of dual-source computed tomography (DSCT) with high-pitch spiral scanning for TAVR. A total of 240 patients being evaluated for TAVR were continuously enrolled. Based on the differences in electrocardiography (ECG) gating and tube voltage, the patients were divided into 4 groups: group A, 70-kV prospective ECG gating, high-pitch helical; group B, 70-kV retrospective ECG gating; group C, 100-kV prospective ECG gating, high-pitch helical; and group D, 120-kV prospective ECG gating, high-pitch helical. Image quality was evaluated on a 4-point scale. The image signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated for objective evaluation. The radiation doses of all patients were recorded. The image quality and radiation dose of each group were compared. There were no differences in age, body mass index (BMI), subjective image quality scores, CT values between the aorta and the coronary artery, or image CNR between the 4 groups. The mean radiation doses of groups A-D were 4.13±0.69, 4.79±0.58, 12.00±1.62, and 15.01±1.90 mSv, respectively. The mean radiation dose in group A (70-kV prospective ECG gating) decreased significantly (P<0.05). Using low-kilovoltage, high-pitch DSCT can provide comparable image quality for TAVR evaluation and significantly reduce the radiation dose.

Platelet Reduction after Aortic Bioprosthesis Implantation: Results from the PORTRAIT Study

Background: Platelet count reduction (PR) is a common but unclear phenomenon that occurs after aortic bioprosthesis valve implantation (bio-AVR). This study aimed to investigate the occurrence and clinical impact of PR in patients receiving stented, rapid deployment (RDV), or stentless bioprostheses. Methods: 1233 adult bio-AVR patients were enrolled. Platelet count variation, early post-operative adverse events, and in-hospital mortality were analysed. Results: 944 patients received a stented valve, an RDV was implanted in 218 patients, and 71 patients had a stentless bioprosthesis. In all groups, the platelet count at discharge was lower than the baseline values (p &lt; 0.001). The percentage of PR was 27% in the stented group, 56% in the RDV group, and 55% in the stentless group. A higher platelet reduction, reaching the minimum platelet value, was observed in the RDV (mean: −30.84, standard error (SE): 5.91, p &lt; 0.001) and stentless (mean: 22.54, SE: 9.10, p = 0.03) groups compared to the stented group. A greater PR occurred as the size of the bioprosthesis increased in RDV (p = 0.01), while platelet count variation was not directly proportional to the stented bioprosthesis size (p &lt; 0.001). PR was not affected by cardiopulmonary bypass (mean: −0.00, SE: 0.001, p = 0.635) or cross-clamp (mean: −0.00, SE: 0.002, p = 0.051) times in any of the groups. RDV subjects experienced more in-hospital adverse events. PR was found to be associated with ischemic strokes in the overall population. Conclusions: Bio-AVR is associated with significant but transient PR. RDV patients more likely experience significant PR and related adverse clinical events. PR is associated with ischemic strokes, regardless of the bioprosthesis type.

Midterm outcomes of aortic valve replacement using a rapid-deployment valve for aortic stenosis: TRANSFORM trial

BackgroundThe use of rapid-deployment valves (RDVs) has been shown to reduce the operative time for surgical aortic valve replacement (AVR). Long-term core laboratory–adjudicated data are scarce, however. Here we report final 7-year data on RDV use. MethodsTRANSFORM was a prospective, nonrandomized, multicenter, single-arm trial implanting a stented bovine pericardial valve with an incorporated balloon-expandable sealing frame. A prior published 1-year analysis included 839 patients from 29 centers. An additional 46 patients were enrolled and implanted, for a total of 885 patients. Annual clinical and core laboratory–adjudicated echocardiographic outcomes were collected through 8 years. Primary endpoints were structural valve deterioration (SVD), all-cause reintervention, all-cause valve explantation, and all-cause mortality. Secondary endpoints included hemodynamic performance assessed by echocardiography. The mean duration of follow-up was 5.0 ± 2.0 years. ResultsThe mean patient age was 73.3 ± 8.2 years. Isolated AVR was performed in 62.1% of the patients, and AVR with concomitant procedures was performed in 37.9%. Freedom from all-cause mortality at 7 years was 76.0% for isolated AVR and 68.2% for concomitant AVR. Freedom from SVD, all-cause reintervention, and valve explantation at 7 years was 97.5%, 95.7%, and 97.8%, respectively. The mean gradient and effective orifice area at 7 years were 11.1 ± 5.3 mm Hg and 1.6 ± 0.3 cm2, respectively. Paravalvular leak at 7 years was none/trace in 88.6% and mild in 11.4%. In patients undergoing isolated AVR, the cumulative probability of pacemaker implantation was 13.9% at 30 days, 15.5% at 1 year, and 21.8% at 7 years. ConclusionsAVR for aortic stenosis using an RDV is associated with low rates of late adverse events. This surgical pericardial tissue platform provides excellent and stable hemodynamic performance through 7 years.