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Objectives: The aim was to evaluate the impact of a bicuspid aortic valve (BAV) on local shear stress and on the pressure profile on the elements of the aortic root (AoR)., Methods: The experiment setup included a BAV with aortic valve stenosis (n = 5 pigs, 67 ± 3.5 kg) and insufficiency (n = 5 pigs, 66.7 ± 4.4 kg). By implanting 6 high-fidelity microsonometric crystals in each AoR, we determined the 3-dimensional (3D) geometry of the AoR. Experimental and geometric data were used to create a 3D time- and pressure-dependent computed fluid dynamic model of the AoR with the BAV., Results: 3D AoR geometry was determined by AoR tilt (α) and rotation angle (β). Both values were maximal at the end of diastole: 24.41 ± 1.70° (α) and 20.90 ± 2.11° (β) for BAV with stenosis and 31.92 ± 11.51° (α) and 20.84 ± 9.80° (β) for BAV with insufficiency and minimal at peak ejection 23.42 ± 1.65° (α), 20.38 ± 1.61° (β) for stenosis and 26.62 ± 7.86° (α), 19.79 ± 8.45° (β) for insufficiency. In insufficiency, low shear stress of 0-0.08 Pa and moderate pressure (60-80 mmHg) were present. In BAV with stenosis, low shear stress of 0-0.5 Pa and moderate pressure (0-20 mmHg) were present at diastole; at peak ejection high shear stress >2 Pa and elevated pressure of >80 mmHg were present., Conclusions: In a BAV with aortic valve stenosis, the haemodynamics are less favourable. The elevated pressure with elevated shear stress may over the long term promote degenerative processes in the leaflets and consequently valve function failure.

Objectives: To treat aortic valve disease and concomitant root disease with transcatheter techniques, 'composite graft' implants are required. Our goal was to assess the suitability of the porcine aortic root for transcatheter root repair tests., Methods: Eight pig hearts explanted from domestic pigs used in experimental surgery were compared to data from the literature on human hearts. The measured diameters included those of the annulus, sinuses of Valsalva, coronary ostia, sinotubular junction, ascending aorta, innominate artery and aortic arch. The measured distances were from the coronary ostia to the nadir of the corresponding annulus; from the innominate artery to the nadir of the corresponding annulus; from the small curvature of the arch to the nadir of the corresponding annulus., Results: The mean weight of the pigs was 89 ± 5.4 kg. The mean aortic annulus diameter was 20 ± 1.2 mm (human: 23.0 ± 2.5 mm), the sinus of Valsalva diameter was 20.5 ± 0.5 mm (human: 31.4 ± 3.4 mm) and the sinotubular junction diameter was 20 ± 0.9 mm (human: 27.2 ± 3.0 mm). The diameter of the mean ascending aorta was 19 ± 0.7 mm (human: 29.3 ± 4 mm); the diameter of the innominate artery was 8.5 ± 0.7 mm, that of the aortic arch was 15 ± 0.7 mm and that of the coronary ostia was 5 ± 0.5 mm (left) and 4.7 ± 0.5 mm (right) (human: 4.8 ± 0.5 mm and 3.7 ± 0.9 mm). The distances from the left and right coronary orifices to the corresponding annuli were 8 ± 1.5 mm and 14 ± 2.4 mm, respectively (human: 14.7 ± 1.3 mm; 15.4 ± 1.7 mm). The distances from the innominate artery to the nadirs of the left and right coronary annuli were 44 ± 4.3 mm and 41 ± 4 mm (human: 80 ± 17 mm). The distance from the curvature of the small arch to the annulus was 35 ± 4.9 mm., Conclusions: The porcine heart can be used as an experimental model to design and test new devices for catheter-based composite repair of the aortic root. Nevertheless, caution is required in using devices with tailored dimensions that must be adapted to the smaller pig's root.

Background: In this study, the effect of aortic valve (AV) pathology on local hemodynamic conditions was evaluated as a potential trigger for the onset of acute type A and B aortic dissection., Methods: A time- and pressure-related four-dimensional (4-D) computed fluid dynamic model of the aorta was established. In an experimental setup, AV stenosis and AV insufficiency were created. 4-D pressure-related geometry of the aortic root (AR) with valve insufficiency and valve stenosis were determined by high-fidelity (200 Hz) microsonometric crystals. Flow and pressure were obtained at the left ventricle, ascending aorta, and aortic arch., Results: Expansion of the AR in AV insufficiency was higher with expansion in AV stenosis, at peak ejection, and at the end of systole. In AV insufficiency, there was low shear stress (0 to 0.6 Pa), turbulent flow, and high pressure (80 to 95 mm Hg) at the anterior wall of the ascending aorta, at the proximal aortic arch, and at the aortic isthmus. In stenosis, high shear stress (>2 Pa) and high pressure (>95 mm Hg) were found at the ascending aorta and at the bifurcation of the brachiocephalic trunk., Conclusions: In AV insufficiency, low shear stresses and turbulent flow regions were documented at the traditional levels of entry tears for acute type A and B dissection. In AV stenosis, high shear stress with elevated pressure at the ascending aorta may be a trigger element for vessel dilatation, aneurysm formation, and intimal tear, which is typical for type A aortic dissection., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Transcatheter aortic valve implantation is indicated in high-risk patients with aortic stenosis. We compared the clinical outcome of 180 consecutive patients who underwent transapical (TA) and transfemoral (TF) procedures in a single centre., Methods: Ninety consecutive TA (TA-group) and 90 consecutive TF (TF-group) were performed from 2009 to 2014. Clinical variables were prospectively collected and retrospectively analysed for hospital outcomes and to identify risk factors for hospital mortality, vascular complications and stroke., Results: Mean age was 80 ± 8.5 and 83 ± 8.4 years, in the TA and TF-group, respectively. TA-group presented higher prevalence of comorbidities: more vascular disease (79% vs 22%, p < 0.001), chronic pulmonary disease (32% vs 10%, p < 0.001), previous vascular surgery (14% vs 4%, p = 0.039), coronary disease (60% vs 40%, p = 0.007), and previous cardiac surgery (28% vs 17%, p = 0.073). Logistic Euroscore was 36 ± 15% in the TA-group and 25 ± 14% in the TF-group (p < 0.001), but hospital mortality was similar (TA:9%, TF:10%, p = 0.799). Access-related vascular complications occurred more often in transfemoral patients (TA:3%, TF:11%, p = 0.081) while major bleeding (TA:3%, TF:4%, p = 1) and stroke (TA:2%, TF:3%, p = 1) were equally distributed. Postoperative renal failure and dialysis were associated with impaired neurological outcome (p = 0.035 and p = 0.020, respectively). Mild to severe paravalvular leak was more prevalent in transfemoral patients (TA:5%, TF:25%, p < 0.001)., Conclusions: In our experience, the TA and TF-group presented different risk profiles but mortality rate and adverse neurological outcome had a similar incidence. The transfemoral approach carried more vascular complications and paravalvular leaks but last-generation devices will improve this outcome.

Objectives: Transapical transcatheter valve procedures are performed through a left minithoracotomy and require apical sutures to seal the apical access site. The use of large-calibre devices compromises any attempt to fully perform the procedure with a thoracoscopic approach or percutaneously. We report our preliminary experience in animals with a new sutureless self-expandable apical occluder, engineered to perform transapical access site closure in a minimally invasive setting with large-size introducer sheaths., Methods: The apical occluder with extendable waist was implanted in six young pigs during an acute animal study. Under general anaesthesia, animals (mean weight: 62 ± 8 kg) received full heparinization (heparin: 100 UI/kg; activated clotting time above 250 s). Through a median sternotomy, a 21-Fr Certitude™ introducer sheath (outer diameter: 25 Fr) was placed over the wire into the cardiac apex. The delivery catheter carrying the constrained apical plug was inserted into the sheath and deployed under fluoroscopic control, whereas the Certitude™ was retrieved. After protamine infusion, we observed and recorded the 1-h bleeding with standard haemodynamic parameters. Animals were sacrificed, and hearts analysed., Results: Six apical closure devices were successfully introduced and deployed in six pig hearts through large-size apical sheaths at first attempt. In all animals, the plugs guaranteed immediate apical sealing and traces of blood were collected in the pericardium during the 1-h observational period (mean of 16 ± 3.4 ml of blood loss per animal). Haemodynamic parameters remained stable during the entire study period and no plug dislodgement was detected with normal systemic blood pressure (mean arterial mean blood pressure: 65 ± 7 mmHg). Post-mortem analysis confirmed the full deployment and good fixation of all plugs, without macroscopic damages to the surrounding myocardium., Conclusions: This sutureless self-expandable apical occluder is a simple device capable of sealing large-size apical access sites (20-35 Fr) in an acute animal study. This approach is a step further towards less invasive transapical valve procedures in the clinical setting, and further animal tests will be performed to confirm the long-term efficacy and safety of this device., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objectives: To evaluate long-term outcome of initial aortic valve intervention in a paediatric population with congenital aortic stenosis, and to determine risk factors associated with reintervention., Patients and Methods: From 1985 to 2009, 77 patients with congenital aortic stenosis and a mean age of 5.8±5.6 years at diagnosis were followed up in our institution for 14.8±9.1 years., Results: First intervention was successful with 86% of patients having a residual peak aortic gradient 1 regurgitation increased by 7%. Long-term survival after the first procedure was excellent, with 91% survival at 25 years. At a mean interval of 7.6±5.3 years, 30 patients required a reintervention (39%), mainly because of a recurrent aortic stenosis. Freedom from reintervention was 97, 89, 75, 53, and 42% at 1, 10, 15, 20, and 25 years, respectively. Predictors of reintervention were residual peak aortic gradient (p=0.0001), aortic regurgitation post-intervention >1 (p=0.02), prior balloon aortic valvuloplasty (p=0.04), and increased left ventricular posterior wall thickness (p=0.1)., Conclusions: Aortic valve intervention is a safe and effective procedure for congenital aortic stenosis with excellent survival results. However, rate of reintervention is high and influenced by increased left ventricular posterior wall thickness pre-intervention, prior balloon valvuloplasty, higher residual peak systolic valve gradient, and more than mild regurgitation post-intervention. The study highlights that long-term follow-up is recommended for these patients.

Objectives: Transcatheter aortic valve replacement (TAVR) provides good results in selected high-risk patients. However, it is unclear whether this procedure carries advantages in extreme-risk profile patients with logistic EuroSCORE above 35%., Methods: From January 2009 to July 2011, of a total number of 92 transcatheter aortic valve procedures performed, 40 'extreme-risk' patients underwent transapical TAVR (TA-TAVR) (EuroSCORE above 35%). Variables were analysed as risk factors for hospital and mid-term mortality, and a 2-year follow-up (FU) was obtained., Results: The mean age was: 81 ± 10 years. Twelve patients (30%) had chronic pulmonary disease, 32 (80%) severe peripheral vascular disease, 14 (35%) previous cardiac surgery, 19 (48%) chronic renal failure (2 in dialysis), 7 (17%) previous stroke (1 with disabilities), 3 (7%) a porcelain aorta and 12 (30%) were urgent cases. Mean left ventricle ejection fraction (LVEF) was 49 ± 13%, and mean logistic EuroSCORE was 48 ± 11%. Forty stent-valves were successfully implanted with six Grade-1 and one Grade-2 paravalvular leakages (success rate: 100%). Hospital mortality was 20% (8 patients). Causes of death following the valve academic research consortium (VARC) definitions were: life-threatening haemorrhage (1), myocardial infarction (1), sudden death (1), multiorgan failure (2), stroke (1) and severe respiratory dysfunction (2). Major complications (VARC definitions) were: myocardial infarction for left coronary ostium occlusion (1), life-threatening bleeding (2), stroke (2) and acute kidney injury with dialysis (2). Predictors for hospital mortality were: conversion to sternotomy, life-threatening haemorrhage, postoperative dialysis and long intensive care unit (ICU) stay. Variables associated with hospital mortality were: conversion to sternotomy (P = 0.03), life-threatening bleeding (P = 0.02), acute kidney injury with dialysis (P = 0.03) and prolonged ICU stay (P = 0.02). Mean FU time was 24 months: actuarial survival estimates for all-cause mortality at 6 months, 1 year, 18 months and 2 years were 68, 57, 54 and 54%, respectively. Patients still alive at FU were in good clinical condition, New York Heart Association (NYHA) class 1-2 and were never rehospitalized for cardiac decompensation., Conclusions: TA-TAVR in extreme-risk patients carries a moderate risk of hospital mortality. Severe comorbidities and presence of residual paravalvular leakages affect the mid-term survival, whereas surviving patients have an acceptable quality of life without rehospitalizations for cardiac decompensation.

Background and Aim of the Study: Transapical transcatheter aortic valve replacement (TAVR) is a new minimally invasive technique with a known risk of unexpected intra-procedural complications. Nevertheless, the clinical results are good and the limited amount of procedural adverse events confirms the usefulness of a synergistic surgical/anesthesiological management in case of unexpected emergencies., Methods: A review was made of the authors' four-year database and other available literature to identify major and minor intra-procedural complications occurring during transapical TAVR procedures. All implants were performed under general anesthesia with a balloon-expandable Edwards Sapien stent-valve, and followed international guidelines on indications and techniques., Results: Procedural success rates ranged between 94% and 100%. Life-threatening apical bleeding occurred very rarely (0-5%), and its incidence decreased after the first series of implants. Stent-valve embolization was also rare, with a global incidence ranging from 0-2%, with evidence of improvement after the learning curve. Rates of valve malpositioning ranged from 0% to < 3%, whereas the risk of coronary obstruction ranged from 0% to 3.5%. Aortic root rupture and dissection were dramatic events reported in 0-2% of transapical cases. Stent-valve malfunction was rarely reported (1-2%), whereas the valve-in-valve bailout procedure for malpositioning, malfunctioning or severe paravalvular leak was reported in about 1.0-3.5% of cases. Sudden hemodynamic management and bailout procedures such as valve-in-valve rescue or cannulation for cardiopulmonary bypass were more effective when planned during the preoperative phase., Conclusion: Despite attempts to avoid pitfalls, complications during transapical aortic valve procedures still occur. Preoperative strategic planning, including hemodynamic status management, alternative cannulation sites and bailout procedures, are highly recommended, particularly during the learning curve of this technique.

Intraoperative cardiac imaging plays a key role during transcatheter aortic valve replacement. In recent years, new techniques and new tools for improved image quality and virtual navigation have been proposed, in order to simplify and standardize stent valve positioning and implantation. But routine performance of the new techniques may require major economic investments or specific knowledge and skills and, for this reason, they may not be accessible to the majority of cardiac centres involved in transcatheter valve replacement projects. Additionally, they still require injections of contrast medium to obtain computed images. Therefore, we have developed and describe here a very simple and intuitive method of positioning balloon-expandable stent valves, which represents the evolution of the 'dumbbell' technique for echocardiography-guided transcatheter valve replacement without angiography. This method, based on the partial inflation of the balloon catheter during positioning, traps the crimped valve in the aortic valve orifice and, consequently, very near to the ideal landing zone. It does not require specific echocardiographic knowledge; it does not require angiographies that increase the risk of postoperative kidney failure in elderly patients, and it can be also performed in centres not equipped with a hybrid operating room.

Transapical aortic valve replacement through an apical aneurysm is traditionally contraindicated because of the risk of severe systemic embolization when thrombi are present. However, a chronic fibrotic aneurysm without apical thrombi carries a low risk of distal embolization and can be safely employed for a transapical transcatheter aortic valve replacement in case of absence of an alternative access site (severe vascular disease, small vascular sizes and diseased calcified aorta). We illustrate our experience with a 73-year-old patient suffering from symptomatic aortic valve stenosis, coronary artery disease with occluded left anterior descending artery, left ventricular apical aneurysm and severe peripheral vascular disease, who successfully underwent a transapical 26 mm Sapien™ XT stent-valve implantation through the fibrotic thin akinetic apical wall.

Transapical transcatheter aortic valve implantation is an emerging technique for high-risk patients with symptomatic aortic valve stenosis, peripheral vascular disease, and severe concomitant comorbidities. However, a previous major surgical intervention involving the left hemithorax and the lung has always been considered a technical surgical challenge or even a potential contraindication for this minimally invasive procedure. With this report, we demonstrate, for the first time, that a previous left pneumonectomy followed by mediastinal radiotherapy does not affect the feasibility of transapical transcatheter aortic valve implantation, and we discuss the preoperative workup and the peculiar intraoperative cardiac imaging and surgical assessment., (© 2010 Wiley Periodicals, Inc.)

Background: Cardiac computed tomographic scans, coronary angiograms, and aortographies are routinely performed in transcatheter heart valve therapies. Consequently, all patients are exposed to multiple contrast injections with a following risk of nephrotoxicity and postoperative renal failure. The transapical aortic valve implantation without angiography can prevent contrast-related complications., Methods: Between November 2008 and November 2009, 30 consecutive high-risk patients (16 female, 53.3%) underwent transapical aortic valve implantation without angiography. The landmarks identification, the stent-valve positioning, and the postoperative control were routinely performed under transesophageal echocardiogram and fluoroscopic visualization without contrast injections., Results: Mean age was 80.1 +/- 8.7 years. Mean valve gradient, aortic orifice area, and ejection fraction were 60.3 +/- 20.9 mm Hg, 0.7 +/- 0.16 cm(2), and 0.526 +/- 0.128, respectively. Risk factors were pulmonary hypertension (60%), peripheral vascular disease (70%), chronic pulmonary disease (50%), previous cardiac surgery (13.3%), and chronic renal insufficiency (40%) (mean blood creatinine and urea levels: 96.8 +/- 54 microg/dL and 8.45 +/- 5.15 mmol/L). Average European System for Cardiac Operative Risk Evaluation was 32.2 +/- 13.3%. Valve deployment in the ideal landing zone was 96.7% successful and valve embolization occurred once. Thirty-day mortality was 10% (3 patients). Causes of death were the following: intraoperative ventricular rupture (conversion to sternotomy), right ventricular failure, and bilateral pneumonia. Stroke occurred in one patient at postoperative day 9. Renal failure (postoperative mean blood creatinine and urea levels: 91.1 +/- 66.8 microg/dL and 7.27 +/- 3.45 mmol/L), myocardial infarction, and atrioventricular block were not detected., Conclusions: Transapical aortic valve implantation without angiography requires a short learning curve and can be performed routinely by experienced teams. Our report confirms that this procedure is feasible and safe, and provides good results with low incidence of postoperative renal disorders., (2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Our experience with the Sapien trans-apical aortic valve (Edwards Lifesciences Inc., Irvine, CA, USA) has been straightforward without per-procedural mortality except in 1/16 consecutive cases who developed non-apical haemorrhage early after valve implantation. We describe the case of an 84-year-old female carrying a very high operative risk (logistic EuroScore of 44%), who underwent a trans-apical stent-valve implantation for severe and symptomatic aortic valve stenosis (23 mm). Due to massive blood loss, an emergency sternotomy and cannulation for cardiopulmonary bypass resuscitation were necessary to treat (without success) an unusual and unexpected subaortic left ventricular free-wall rupture that occurred few minutes after the stent-valve positioning and implantation. To the best of our knowledge, this is the first described case of a left ventricular free-wall rupture occurring after an otherwise non-complicated standard catheter-based aortic valve replacement., (Copyright 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)

The trans-apical aortic valve implantation (TA-AVI) is an established technique for high-risk patients requiring aortic valve replacement. Traditionally, preoperative (computed tomography (CT) scan, coronary angiogram) and intra-operative imaging (fluoroscopy) for stent-valve positioning and implantation require contrast medium injections. To preserve the renal function in elderly patients suffering from chronic renal insufficiency, a fully echo-guided trans-catheter valve implantation seems to be a reasonable alternative. We report the first successful TA-AVI procedure performed solely under trans-oesophageal echocardiogram control, in the absence of contrast medium injections.

Aims: To critically review the available transcatheter aortic valve implantation techniques and their results, as well as propose recommendations for their use and development., Methods and Results: A committee of experts including European Association of Cardio-Thoracic Surgery and European Society of Cardiology representatives met to reach a consensus based on the analysis of the available data obtained with transcatheter aortic valve implantation and their own experience. The evidence suggests that this technique is feasible and provides haemodynamic and clinical improvement for up to 2 years in patients with severe symptomatic aortic stenosis at high risk or with contraindications for surgery. Questions remain mainly concerning safety and long-term durability, which have to be assessed. Surgeons and cardiologists working as a team should select candidates, perform the procedure, and assess the results. Today, the use of this technique should be restricted to high-risk patients or those with contraindications for surgery. However, this may be extended to lower risk patients if the initial promise holds to be true after careful evaluation., Conclusion: Transcatheter aortic valve implantation is a promising technique, which may offer an alternative to conventional surgery for high-risk patients with aortic stenosis. Today, careful evaluation is needed to avoid the risk of uncontrolled diffusion.

Objective: To compare the outcome and the 1-year hemodynamic results of the rapid-deployment Intuity valve versus the Perimount Magna bioprosthesis in matched populations.Methods: Between March 2014 and May 2015, 32 patients underwent aortic valve replacement with the Intuity valve (Intuity-group). These patients were compared to a matched population of Perimount valves implanted during the same period of time (Perimount-group). Clinical data were compared and echocardiographic 1-year follow-up was performed.Results: There were more female patients in the Intuity-group (47% vs 22%, p = 0.035); mean age was 78 ± 5.6 and 72.5 ± 6 years in the Intuity-group and Perimount-group (p < 0.001); coronary disease was more common in the Intuity-group (65% vs 25%, p = 0.005). Other characteristics were similar. Implants were 100% successful. Mean cross-clamp (50.3 ± 25 vs 53 ± 22 min, p = 0.004), cardiopulmonary bypass (68 ± 27 vs 72 ± 31.8 min; p = 0.006), and surgical times (156.8 ± 54 vs 165 ± 40 min; p = 0.018) were shorter with the Intuity despite more concomitant procedures. Mean valve size was 23.7 mm (Intuity-group) and 24.1 mm (Perimount-group); hospital mortality was zero (Intuity-group) and 3% (Perimount-group); new pacemaker implants were 6% (Intuity) and 3% (Perimount) (p = 0.55) and hospital stay was equivalent. Mean gradients were: 9.9 ± 3.4 (Intuity) versus 12.5 ± 3.8 mmHg (Perimount) (p = 0.022) at discharge and 9 ± 4 mmHg (Intuity) versus 14 ± 4 mmHg (Perimount) (p = 0.02) at follow-up. At discharge, one Intuity valve had 3+ aortic insufficiency (AI) which was unchanged at 1 year and will require an intervention. Another patient had 1 + AI which progressed to 2+ at 1 year. There were no paravalvular leaks in the Perimount valves at discharge and follow-up.Conclusion: Intuity valves showed lower gradients compared to Perimount valves with the same mean size. Paravalvular leaks identified at the time of implantation in Intuity valves need to be addressed at the time of surgery. [ABSTRACT FROM AUTHOR]