Excellent Hemodynamics Research Articles

Evaluation of an engineered vascular graft exhibiting somatic growth in lambs to model repair of absent pulmonary artery branch

BackgroundGrowth is the holy grail of tissue implants in pediatrics. No vascular graft currently in use for surgical repairs of congenital heart defects has somatic growth capacity.MethodsBiologically-engineered grafts (6 mm) grown from donor ovine fibroblasts in a sacrificial fibrin gel were implanted into the left pulmonary branch of 3-month old lambs for 3, 6, and 18 months. A control group of Propaten® PTFE grafts was implanted for 6 months.ResultsThe engineered grafts exhibit extensive site-appropriate recellularization after only 3 months and near-normal increase of diameter from the preimplant value of 6 mm to 12.9 mm and also a doubling of length from 6.0 mm to 13.0 mm at 6 months (n = 3) associated with apparent somatic graft growth (collagen content increase of 265% over 18-month, n = 2), along with excellent hemodynamics and no calcification, in contrast to the Propaten® grafts. The left-right flow distribution is nearly 50–50 for the engineered grafts at 6 months (n = 3) compared to about 20–80 for the Propaten® grafts (n = 3), which have less than one-half the diameter, a 6-fold higher pressure gradient, and stunted vascular development downstream of the graft. The engineered grafts exhibit a stable diameter over months 12–18 when the lambs become adult sheep (n = 2).ConclusionsThis study supports the use of these regenerative grafts with somatic growth capacity for clinical trial in patients born with a unilateral absent pulmonary artery branch, and it shows their potential for improving development of the downstream pulmonary vasculature.

Short-Term Results With Ozaki Valved Conduit-A Simple Solution for Patients Needing Right Ventricle to Pulmonary Artery Conduit in a Low-Resource Setting.

The repair of certain types of complex congenital cardiac defects may require a right ventricle-pulmonary artery (RV-PA) conduit. Using the Ozaki Aortic valve neocuspidization (AVNeo)technique, a valved RV-PA conduit was constructed with an Ozaki valve inside a Dacron graft. This study aims to evaluate the short-term outcome of the Ozaki valved RV-PA conduit. A total of 22 patients received the Ozaki valved RV-PA conduit from November 2019 until December 2023. The median age was 12 years (interquartile range [IQR], 5.5-21), median body weight was 35 kg (IQR, 15.8-48.5). The conduit was used in 16 patients (72.7%) under 18 years of age. Indications for conduit placement included: anatomic repair of corrected transposition of the great arteries, ventricular septal defect/pulmonary stenosis, conduit replacement, pulmonary atresia with associated anomalies, pulmonary artery aneurysm with dysplastic pulmonary valve, tetralogy of Fallot with coronary artery crossing the right ventricular outflow tract, bioprosthetic pulmonary valve regurgitation, and rheumatic heart disease. Native pericardium was used for the Ozaki valve in 12 patients and bovine pericardium for 10 patients. Conduit sizes ranged from 18 mm to 30 mm. The median intensive care unit stay was 4 (IQR, 2-6) days and the median hospital stay was 9 (IQR, 5.5-13.5) days. There were two perioperative mortalities (9.1%) both unrelated to the conduit. The median follow-up was 12.3 (IQR, 4.43-21.2) months. There was no infective endocarditis of the conduit. The median peak gradient across the conduit was 22 mm Hg (range 0-44 mm), and all were competent with trivial regurgitation on follow up. Creation of an Ozaki valved conduit is an attractive option due to low cost, reproducibility, and excellent hemodynamics. Longer-term studies are needed to confirm the durability.

Quadratus Lumborum Block versus Transversus Abdominis Plane Block for Postoperative Pain Management after Total Abdominal Hysterectomy

Background: Post-operative analgesia is of vital importance to prevent various undesirable side effects such as respiratory complications, venous thromboembolism, and increased hospital stay. The transversus abdominis plane (TAP) block and Quadratus lumborum (QL) block has been used for post-operative pain relief in various abdominal surgeries as part of the multimodal analgesic approach. Therefore, this randomized, prospective study was conducted to compare the post-operative analgesic efficacy of QL block and TAP block in patients undergoing abdominal hysterectomy.Methods: This study was carried out in the Department of Anaesthesia, Analgesia, Palliative & Intensive Care Medicine, Dhaka Medical College Hospital, Dhaka. Patients of ASA status I and II, planned for total abdominal hysterectomy under spinal anaesthesia were selected and randomly allocated into two groups (Group A – TAP Block and Group B – QL Block). Hemodynamic status, time of onset of sensory block, mean duration of postoperative analgesia, the amount of rescue analgesic requirements as well as intensity of post-operative pain were assessed at different point of time. Visual analog scale (VAS) was used to assess the postoperative pain. Total morphine consumption in 24 hours and time required for 1st postoperative analgesic were recorded.Results: A total of 60 patients were included in this study. The onset of sensory block was faster in Group B than A (22.6±6.5 min & 16.3±5.2 min). VAS score was higher among group A at 10th hours and 18th hours. In case of group B, VAS score was more at 14th hour. Post operatively 1st demand of analgesia was earlier in Group-A (10.4±1.5 vs 14.1±1.7) (p< 0.001). Total analgesic requirement was higher in Group- A than Group B (18.7±4.6 vs11.2±3.8) (p< 0.001).Conclusion: Quadratus Lumborum Block produces longer duration of analgesia, provides optimum post-operative pain control and maintain an excellent hemodynamics than TAP block in patients undergoing abdominal hysterectomy.

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.

A Modified Technique for Transcatheter Pulmonary Valve Implantation of SAPIEN 3 Valves in Large Right Ventricular Outflow Tract: A Matched Comparison Study.

Percutaneous pulmonary valve implantation (PPVI) with a SAPIEN 3 valve is effective for treating treat right ventricle outflow (RVOT) dysfunction. A modified technique was developed without prestenting using a protective valve delivery method. We aimed to compare the procedural results of the modified technique group (MTG) to those of patients in a conventional technique group (CTG). We designed a matched before-after study. All consecutive PPVI with SAPIEN 3 performed in the MTG over 9 months were matched, based on the RVOT type and size, to consecutive procedures performed previously with SAPIEN 3. A total of 54 patients were included, equally distributed in the two groups. The sizes of the SAPIEN 3 valves were 23 mm (n = 9), 26 mm (n = 9), 29 mm (n = 36). The two groups were similar regarding demographic data, RVOT type, and pre-procedure hemodynamics. PPVI was performed in a single procedure in all patients of the MTG, whereas six (22.2%) patients of the CTG group underwent prestenting as a first step and valve implantation later (p = 0.02). The procedures were successful in all cases. Stent embolization was reported in two patients (7.4%) in the CTG, which were impacted in pulmonary arteries. In one case (3.7%), in the MTG, an unstable 29 mm SAPIEN 3 valve was stabilized with two stents and additional valve-in-valve implantation. The hemodynamics results were good in all cases, without significant differences between the two groups. The procedures' durations and fluoroscopy times were significantly reduced in the MTG (48.1 versus 82.6 min, p < 0.0001; 15.2 versus 29.8 min, p = 0.0002). During follow-up, neither stent fracture nor valve dysfunction was noticed in either group. PPVI without prestenting and with a protective delivery method of the SAPIEN 3 valve significantly reduces the procedure's complexity, the duration, and the irradiation while maintaining excellent hemodynamics results in selected cases.

In vivo performance of a tri-leaflet mechanical heart valve prosthesis in an ovine model.

We present the long-term results of a trileaflet (Triflo) versus bileaflet (On-X) mechanical valve in both aortic and pulmonary positions in a sheep model. The Triflo valve was implanted in 21 female sheep in aortic (n = 8) and pulmonary position (n = 13). The On-X valve was implanted in 7 female sheep in aortic (n = 1) and pulmonary (n = 6) positions. No antithrombotic medication of any kind was given postoperatively. In the aortic group, survival cohorts were 3 and 5 months. In the pulmonary group, survival cohorts were 10 and 20 weeks. Valve performance was assessed using haematology, echocardiography and acoustic measurements combined with post-mortem pathology analysis of the downstream organs. The mean gradients were lower for the Triflo valve in both pulmonary [4.30 mmHg (3.70-5.73) vs 6.80 mmHg (4.63-7.96), P = 0.012] and aortic [5.1 mmHg (4.2-7.7) vs 10.7 mmHg (8.7-12.9), P = 0.007] positions. Peak gradients were lower for the Triflo valve in both pulmonary [8.05 mmHg (6.75-10.23) vs 13.15 mmHg (9.20-14.76), P = 0.005] and aortic [8.7 mmHg (7.5-12.5) vs 16.5 mmHg (14.2-19.6), P = 0.009] positions. In both positions, leaflets and housing surface were free from any deposits macro- and microscopically and comparable to nonimplanted control valves. Peripheral organs showed no signs of thrombo-embolic damage. Biochemical and haematological were comparable to preoperative. The closing click sound pressure level of the Triflo was significantly lower in both aortic [108.4 sound pressure level (102.0-115.7) vs 111.7 sound pressure level (105.5-117.0), P < 0.001] and pulmonary [103.6 sound pressure level (99.1-108.9) vs 118.5 sound pressure level (116.7-120.2), P < 0.001] position. Preliminary in vivo results of the Triflo valve are promising in both aortic and pulmonary positions in an ovine model. Excellent haemodynamics, stable long-term function, low valve noise and no thrombo-embolic events in the absence of antithrombotic medication lay the foundation to a future clinical first-in-man trial.

Fate of transposition of the great arteries with pulmonary stenosis after double-root translocation, Rastelli, and Réparation à l’Etage Ventriculaire

ObjectivesFor transposition of the great arteries with unrestricted ventricular septal defect and pulmonary stenosis, double-root translocation is reported to reconstruct ideal double artery roots with growth potential. However, prospective long-term studies describing the long-term outcomes are still scarce. Therefore, the aim was to assess development of double artery roots, hemodynamics, and freedom from death and heart failure 17 years after double-root translocation, Rastelli, and Réparation à l’Etage Ventriculaire procedures. MethodsIn this prospective population-based study, 266 patients with transposition of the great arteries/ventricular septal defect/pulmonary stenosis (from July 2004 to August 2021) were consecutively included before surgery. All patients were divided into 3 groups based on the type of operation: double-root translocation (174), Rastelli (68), and Réparation à l’Etage Ventriculaire (24), who accepted postoperative evaluations annually. Generalized linear mixed model analysis was performed to determine growth potential of artery roots. ResultsLongitudinal repeated computed tomography measurements show the pulmonary root has significantly increased diameter (0.62 [0.03] mm/y, P < .001) over time and an adequate Z-score (−0.18) at the last follow-up only in the double-root translocation group. The pressure gradients of double outflow tracts in the double-root translocation group were the least among 3 groups. The probabilities of freedom from death/heart failure at the 15th year were 73.1%, 59.3%, and 60.9% in the double-root translocation, Rastelli, and Réparation à l’Etage Ventriculaire groups, respectively (double-root translocation vs Rastelli, P = .026; double-root translocation vs Réparation à l’Etage Ventriculaire, P = .009; Rastelli vs Réparation à l’Etage Ventriculaire, P = .449). ConclusionsBy reconstructing ideal double artery roots, double-root translocation can provide postoperative long-term excellent hemodynamics and minimal death and heart failure for patients with transposition of the great arteries/ventricular septal defect/pulmonary stenosis.

Structural Valve Deterioration of Trifecta Valve: Mechanism and Management at a New Zealand Tertiary Centre

The increasing use of bioprosthetic aortic valves remains limited by structural valve deterioration (SVD), with both patient and valve-related factors contributing to early failure. The Trifecta valve (Abbott, St Paul, MN, USA) has excellent haemodynamics due to its external mounting; however, it has been identified as having higher rates of early failure. This study examined the overall safety of the Trifecta valve, the rates of failure, and management options of early Trifecta failure at a New Zealand tertiary hospital.

Bioinspired NiTi-reinforced polymeric heart valve exhibiting excellent hemodynamics and reduced stress

The durability of the current polymeric heart valves remains to be improved, which has proven to be highly dynamics and species dependent. Herein, inspired by the fiber-reinforced structure of native valve leaflets, we developed a valve prototype with the polymer matrix reinforced by NiTi wires in the radial direction, to achieve both desirable dynamics control and stress reduction. Textile technology and computer modeling were primarily utilized for integrated construction and biomimetic geometry. The NiTi-reinforced textile composites had suitable properties with valve leaflets. The pulsating flow tests confirmed that the systolic hemodynamics and leaflet kinetics were significantly optimized through the stiffness-domination of NiTi wires. Particle imaging velocimetry measurements revealed the satisfactory flow field characteristic for VP40-RA6 when compared with other reinforced valves. Furthermore, the finite element analysis indicated that the maximum principal stress and the area percentage of that were significantly reduced. As a preliminary proof-of-concept, this novel valve prototype exhibited excellent comprehensive performance which would be beneficial for the further improvement of long-term durability and provide new insight into the design modification of heart valve prosthesis.

Case Series of Early Structural Valve Deterioration of Trifecta Bioprosthesis - New Zealand Experience.

Structural valve deterioration (SVD) remains a limitation on the use of bioprosthetic valves, with patient and valve-related factors contributing to early SVD. The Trifecta valve has been reported to have excellent hemodynamics but studies have highlighted early failure. We present a review and case series at a New Zealand tertiary hospital defining early SVD as failure within 3 years of implant. A retrospective review from January 2015 to July 2019 included 525 patients undergoing surgical aortic valve replacement with 263 patients receiving an Abbott Trifecta or Trifecta Glide Technology (GT) valve. Our review found an acceptable safety profile for the valve with excellent hemodynamics, with a low mortality, stroke, and permanent pacemaker rate. Three patients out of 263 were identified from the study period as having early SVD requiring reintervention within 3 years of valve implantation leading to a 1.14% failure rate. One of the valves that had early SVD was a new generation Trifecta GT. An additional four patients were identified to have valves implanted prior to the study period and had valve failure at greater than 3 years post implantation. Five cases had cusp tears as their mechanism of failure, raising concerns about durability. The Trifecta valve has an acceptable safety profile and offers good hemodynamics due to the externally mounted leaflets. However, our experience of early SVD and failure is concerning for valve durability. Further comparison to other bioprosthetic valves and longer term follow-up are required to characterize the mechanism of failures.

Sutureless aortic valve replacement in pure aortic regurgitation: expanding the indications

BackgroundIn the era of transcatheter methods, patients presenting with a pure aortic regurgitation (AR) are not considered eligible for transcatheter treatment and therefore require another less invasive surgical option. We sought to review our experience with sutureless aortic valve replacement (SU-AVR) in patients presenting with symptomatic pure AR, which until now is a contraindication for implementation of sutureless valve prostheses in Europe.MethodsBetween April 2018 and June 2021, 80 consecutive patients underwent a SU-AVR for various indications at our institution. We analyzed the outcomes and postoperative complications of 12 patients presenting with a pure severe AR undergoing SU-AVR using Perceval (Corcym).ResultsThe mean age of the patients was 67 ± 9.1 years old. All patients presented with symptomatic pure AR. Patients presented with multiple comorbidities as reflected by the mean EuroSCORE-II of 3.6 ± 2.6%. Six patients (50%) underwent a concomitant CABG procedure. The mean operating- and cross clamp time was 127.25 ± 45.9 and 40.33 ± 17.3 min respectively. All isolated SU-AVR were performed via J-sternotomy or right anterolateral thoracotomy. There were no cases of device dislocation. No patients presented with a paravalvular leakage. We observed excellent mean postoperative pressure gradient at follow-up 5.7 ± 1.5 mmHg.ConclusionsOur experience with SU-AVR shows the feasibility of sutureless technologies in the aortic valve surgery due to pure AR. Besides the great technical success and excellent hemodynamics, SU-AVR in severe AR offers a great opportunity of reducing the invasivity of the surgical procedure and potentially reducing hospital cost without compromising the postoperative outcomes and in-hospital length of stay.

Transcatheter Aortic Valve Implantation with ACURATE neo: Results from the PROGRESS PVL Registry.

Objectives The PROGRESS PVL registry evaluated transcatheter aortic valve implantation (TAVI) in patients treated with ACURATE neo, a supra-annular self-expanding bioprosthetic aortic valve. Background While clinical outcomes with TAVI are comparable with those achieved with surgery, residual aortic regurgitation (AR) and paravalvular leak (PVL) are common complications. The ACURATE neo valve has a pericardial sealing skirt designed to minimize PVL. Methods The primary endpoint was the rate of total AR over time, as assessed by a core echocardiographic laboratory. The study enrolled 500 patients (mean age: 81.8 ± 5.1 years; 61% female; mean baseline STS score: 6.0 ± 4.5%) from 22 centers in Europe and Canada; 498 patients were treated with ACURATE neo. Results The rate of ≥ moderate AR was 4.6% at discharge and 3.1% at 12 months; the rate of ≥ moderate PVL was 4.6% at discharge and 2.6% at 12 months. Paired analyses showed significant improvement in overall PVL between discharge and 12 months (P < 0.001); 64.6% of patients had no change in PVL grade, 24.9% improved, and 10.5% worsened. Patients also exhibited significant improvement in transvalvular gradient (P < 0.001) and effective orifice area (P=0.01). The mortality rate was 2.2% at 30 days and 11.3% at 12 months. The permanent pacemaker implantation (PPI) rate was 10.2% at 30 days and 12.2% at 12 months. Conclusions Results from PROGRESS PVL support the sustained safety and performance of TAVI with the ACURATE neo valve, showing excellent valve hemodynamics, good clinical outcomes, and significant interindividual improvement in PVL from discharge to 12-month follow-up.

A word of caution: Spontaneous rupture of the noncoronary sinus of the Freestyle xenograft: Two cases and review of the literature

The porcine stentless Freestyle xenograft (Medtronic Inc) has proved to be an ideal substitute for aortic root replacement (ARR) as it provides excellent hemodynamics and durability.1,2 Nonetheless, like other bioprostheses, structural valve deterioration is observed in the long term, mostly due to aortic cusp tears. However, spontaneous rupture of the Freestyle xenograft aortic wall has also been reported.3,4 We present 2 patients who developed pseudoaneurysm after ARR using a Freestyle xenograft, related to spontaneous rupture of the noncoronary sinus (NCS) of Valsalva.

Sutureless Valve in Bicuspid Aortic Stenosis: Modified Technique and Midterm Outcome.

The sutureless valve has gained popularity for degenerative aortic valve stenosis but not congenital bicuspid aortic valve (BAV) due to anatomical challenges. We reviewed our modified implant techniques for patients with BAV. From June 2015 to June 2019, 66 patients with aortic valve stenosis were treated with the Perceval sutureless valve, 20 of whom had BAV. The demographics, type of BAV (the Sievers classification), and associated pathologies, surgical outcomes, and midterm hemodynamics were recorded. The median age was 64 (range: 49-81) years and the Society of Thoracic Surgeons score was 2.186 (range: 0.407-6.384). Annular plication was performed in 9 (75%) of 12 type 0 and 3 (37.5%) of 8 type I, with implanted valve sizes of M, L, and XL in 6, 10, 4 cases, respectively. Three patients, all type 0 in the initial learning periods, required intraoperative redeployment due to malposition of the valve. The final implant was successful in all without conversion to traditional prosthesis. The median extubation time was 4 hours and the durations of intensive care unit and hospital stay were 1 and 6 days. At a median follow-up of 46 (23-72) months, there was one late mortality due to hemorrhagic stroke sequel. The last echo revealed none had more than mild paravalvular leakage and the mean transvalvular pressure gradient remained stable at 9.70 (range: 6.94-15.0) mm Hg. The sutureless valve can achieve satisfactory outcomes in BAV without paravalvular leakage and excellent hemodynamics. It may serve as the benchmark for transcatheter aortic valve implantation in this unique population.

Modified technique of percutaneous pulmonary valve implantation with the Sapien 3: Impact on procedure and early outcome

Percutaneous pulmonary valve implantation (PPVI) with Sapien 3 valve is effective to treat right ventricle outflow (RVOT) dysfunction. Issues related to presenting and tricuspid valve injuries were reported with the initial implantation method. A modified technique was developed without pre-stenting and with a protective delivery method for valve implantation. We aimed to compare procedural results in the modified technique group (MTG) to matched patients in a conventional technique group (CTG). All consecutive procedures performed in the MTG over 9 months were matched based on RVOT type and size to consecutive procedures performed before. 27 patients were included in each group. Size of the Sapien 3 valves were 23 mm (n = 9), 26 mm (n = 9), 29 mm (n = 36). The two groups were similar regarding demographic data, RVOT type, pre-procedure hemodynamics. PPVI was performed in a single procedure in all patients of the MTG, whereas six (22.2%) patients of the CTG group had pre-stenting as a first step and valve implantation later (P = 0.02). Procedures were successful in all cases. Stent embolization was reported in two patients (7.4%) in the CTG, which were impacted in pulmonary arteries. Instability of a valve was observed in one case (3.7%) in the MTG, stabilized with two stents and an additional valve-in-valve implantation. Hemodynamics results were good in all cases without significant difference among the two groups (Table 1). Procedure duration and fluoroscopy times were significantly reduced in the MTG (48.1 versus 82.6 minutes, P < 0.0001; 15.2 versus 29.8 minutes, P = 0.0002). During follow-up, no stent fracture or valve dysfunction was noticed in both groups. PPVI without pre-stenting and with a protective delivery method of the Sapien 3 valve reduces significantly the procedure complexity, procedure duration and irradiation, while maintaining excellent hemodynamics results.

Modified technique of percutaneous pulmonary valve implantation with the Sapien 3: Impact on procedure and early outcome

Percutaneous pulmonary valve implantation (PPVI) with Sapien 3 valve is effective to treat right ventricle outflow (RVOT) dysfunction. Issues related to presenting and tricuspid valve injuries were reported with the initial implantation method. A modified technique was developed without pre-stenting and with a protective delivery method for valve implantation. We aimed to compare procedural results in the modified technique group (MTG) to matched patients in a conventional technique group (CTG). All consecutive procedures performed in the MTG over 9 months were matched based on RVOT type and size to consecutive procedures performed before. Twenty-seven patients were included in each group. Size of the Sapien 3 valves were 23 mm ( n = 9), 26 mm ( n = 9), 29 mm ( n = 36). The two groups were similar regarding demographic data, RVOT type, pre-procedure hemodynamics ( Table 1 ). PPVI was performed in a single procedure in all patients of the MTG, whereas six (22.2%) patients of the CTG group had pre-stenting as a first step and valve implantation later ( P = 0.02). Procedures were successful in all cases. Stent embolization was reported in two patients (7.4%) in the CTG, which were impacted in pulmonary arteries. Instability of a valve was observed in one case (3.7%) in the MTG, stabilized with two stents and an additional valve-in-valve implantation. Hemodynamics results were good in all cases without significant difference among the two groups ( Table 2 ). Procedure duration and fluoroscopy times were significantly reduced in the MTG (48.1 versus 82.6 minutes, P < 0.0001; 15.2 versus 29.8 minutes, P = 0.0002). During follow-up, no stent fracture or valve dysfunction was noticed in both groups. PPVI without pre-stenting and with a protective delivery method of the Sapien 3 valve reduces significantly the procedure complexity, procedure duration and irradiation, while maintaining excellent hemodynamics results.

Preclinical Testing of Living Tissue-Engineered Heart Valves for Pediatric Patients, Challenges and Opportunities.

Introduction: Pediatric patients with cardiac congenital diseases require heart valve implants that can grow with their natural somatic increase in size. Current artificial valves perform poorly in children and cannot grow; thus, living-tissue-engineered valves capable of sustaining matrix homeostasis could overcome the current drawbacks of artificial prostheses and minimize the need for repeat surgeries.Materials and Methods: To prepare living-tissue-engineered valves, we produced completely acellular ovine pulmonary valves by perfusion. We then collected autologous adipose tissue, isolated stem cells, and differentiated them into fibroblasts and separately into endothelial cells. We seeded the fibroblasts in the cusp interstitium and onto the root adventitia and the endothelial cells inside the lumen, conditioned the living valves in dedicated pulmonary heart valve bioreactors, and pursued orthotopic implantation of autologous cell-seeded valves with 6 months follow-up. Unseeded valves served as controls.Results: Perfusion decellularization yielded acellular pulmonary valves that were stable, no degradable in vivo, cell friendly and biocompatible, had excellent hemodynamics, were not immunogenic or inflammatory, non thrombogenic, did not calcify in juvenile sheep, and served as substrates for cell repopulation. Autologous adipose-derived stem cells were easy to isolate and differentiate into fibroblasts and endothelial-like cells. Cell-seeded valves exhibited preserved viability after progressive bioreactor conditioning and functioned well in vivo for 6 months. At explantation, the implants and anastomoses were intact, and the valve root was well integrated into host tissues; valve leaflets were unchanged in size, non fibrotic, supple, and functional. Numerous cells positive for a-smooth muscle cell actin were found mostly in the sinus, base, and the fibrosa of the leaflets, and most surfaces were covered by endothelial cells, indicating a strong potential for repopulation of the scaffold.Conclusions: Tissue-engineered living valves can be generated in vitro using the approach described here. The technology is not trivial and can provide numerous challenges and opportunities, which are discussed in detail in this paper. Overall, we concluded that cell seeding did not negatively affect tissue-engineered heart valve (TEHV) performance as they exhibited as good hemodynamic performance as acellular valves in this model. Further understanding of cell fate after implantation and the timeline of repopulation of acellular scaffolds will help us evaluate the translational potential of this technology.

A novel alternative: transapical transcatheter mitral valve-in-valve implantation using J-Valve for failed bioprosthesis.

BackgroundFailed mitral bioprosthesis has conventionally been treated with redo surgical mitral valve replacement (SMVR). Transcatheter mitral valve-in-valve implantation (TM-VIVI) is emerging as an alternative to SMVR in high-risk patients. We report our experience with transapical TM-VIVI using the J-Valve system.MethodsFrom May 2020 to January 2021, 21 patients with a failed mitral bioprosthesis underwent transapical TM-VIVI without concomitant procedures at Guangdong Provincial People’s hospital. The mean age was 74.62 years. All patients were heavily symptomatic with severe mitral regurgitation and increased trans-prosthetic gradient. The Society of Thoracic Surgeons predicted risk of mortality (STS PROM) and European System for Cardiac Operative Risk Evaluation II (EuroScore II) scores were used and predicted high mortality (STS PROM, 12.91%±9.94%; EuroScore II, 12.04%±10.5%). All the procedures were performed in a hybrid room.ResultsThe success rate was 100% with no conversion to median sternotomy and no intraprocedural death. The mean ventilation time and intensive care unit (ICU) stay were 25±21.44 minutes and 4.14±7.08 days, respectively. No major postoperative complications were observed, except 1 patient suffered pneumonia and required tracheostomy. All patients recovered well. Postoperative echocardiography revealed excellent hemodynamics with no residual mitral regurgitation in 19 patients and mild regurgitation in 2 patients. In a subgroup analysis, no significant differences among procedural and postoperative outcomes were detected in patients with previous aortic-mitral double valve replacement (DVR) compared to other patients.ConclusionsOur results demonstrate the safety and feasibility of transapical TM-VIVI using the J-Valve system, even in patients following DVR.

The Ross procedure in children: a systematic review.

The Ross procedure involves autograft transplantation of the native pulmonary valve into the aortic position and reconstruction of the right ventricular outflow tract (RVOT) with a homograft. The operation offers the advantages of a native valve with excellent hemodynamic performance, the avoidance of anticoagulation, and growth potential. Conversely, the operation is technically demanding and imposes the risk of turning single-valve disease into double-valve disease. This systematic review reports outcomes of pediatric patients undergoing the Ross procedure. An electronic search identified studies reporting outcomes on pediatric patients (mean age <18 years, max age <21 years) undergoing the Ross procedure. Long-term outcomes, including early mortality, late mortality, sudden unexpected unexplained death, reoperation due to failure of the pulmonary autograft or RVOT reconstruction, thromboembolic events, bleeding events, and endocarditis-related complications, were evaluated. Upon review of 2,035 publications, 30 studies and 3,156 pediatric patients were included. Patients had a median age of 9.5 years and median follow-up period of 5.7 years. Early mortality rates varied from 0.0 to 17.0% and were increased in the neonatal population. Late mortality rates were much lower (0.04-1.83%/year). Reoperation due to pulmonary autograft failure occurred at rates of 0.37-2.81%/year and reoperation due to RVOT reconstruction failure was required at rates of 0.34-4.76%/year. Thromboembolic, bleeding, and endocarditis events were reported to occur at rates of 0.00-0.58, 0.00-0.39, and 0.00-1.68%/year, respectively. The Ross operation offers a durable aortic valve replacement (AVR) option in the pediatric population that offers favorable survival, excellent hemodynamics, growth potential, decreased risk of complications, and avoidance of anticoagulation. Larger multi-institutional registries focusing on pediatric patients are necessary to provide more robust evidence to further support use of the Ross procedure in this population.

Aortic valve replacement in sheep with a novel trileaflet mechanical heart valve prosthesis without anticoagulation

BackgroundEven after decades of intensive research, an ideal heart valve prosthesis remains elusive. Shortcomings of conventional devices include reduced durability of bioprostheses and the thrombogenicity of mechanical substitutes, necessitating anticoagulation and resulting in imperfect hemodynamics. Here we present in vivo results of a novel mechanical heart valve prosthesis aiming for freedom from anticoagulation. MethodsFour female sheep had their aortic valves replaced using the novel mechanical heart valve (size 21 mm), with no postoperative anticoagulation treatment. This trileaflet heart valve was designed with the pivots in the systolic central flow. Hemodynamics, biochemistry, hematology, and macroscopy and microscopy were studied at 90 days in 2 sheep and at 1 year in the other 2 sheep. ResultsMean (<6 mm Hg) and peak (<10 mm Hg) aortic transvalvular gradients remained low during the study period. Aortic regurgitation was trivial, and central traces were only rarely observed. The rate of thrombotic events was very low, with none macroscopically and microscopically visible thrombotic material on the device. Biochemistry and hemotology were unchanged without hemolysis. In 3 sheep, the fibrous pannus and mitral leaflet were partially folded over the edge of the annular body. Apart from organic/inorganic deposits on the leaflets after 1 year, the ultrastructurally evaluated leaflets were similar to those of nonimplanted controls. ConclusionsThe preliminary in vivo results of this novel anticoagulation-free aortic mechanical heart valve are promising with excellent hemodynamics and a very low risk of thrombotic events.