nitinol and Aortic-Valve-Stenosis

The degenerative, calcified aortic stenosis is the most common form of adult valvular heart disease. Surgical aortic valve replacement is the method of choice and can be performed at low risk in suitable candidates. However, a fair amount of patients is rejected from surgery due to old age and preexisting comorbidities increasing operative mortality. For this reason frequently operation is not accomplished. Today, with the development of percutaneous aortic valve replacement, the treatment of aortic stenosis has entered a new era providing a new durable treatment option.

Topics: Aged; Aged, 80 and over; Alloys; Angiography; Angioplasty; Aortic Valve Stenosis; Bioprosthesis; Clinical Trials as Topic; Female; Follow-Up Studies; Heart Valve Prosthesis; Humans; Male; Prosthesis Design

The CENTERA transcatheter heart valve (THV) is a low-profile, self-expanding nitinol valve made from bovine pericardial tissue that is 14-F compatible with a motorized delivery system allowing for repositionability.. The pivotal study evaluated safety and efficacy of this THV in high-surgical-risk study patients with severe symptomatic aortic stenosis.. Implantations were completed in 23 centers. Clinical and echocardiographic outcomes were assessed at baseline, discharge, and 30 days. Major events were adjudicated by an independent clinical events committee. Echocardiograms and computed tomography scans were reviewed by core laboratories. The primary endpoint was all-cause mortality at 30 days.. Between March 25, 2015 and July 5, 2016, 203 patients with severe symptomatic aortic stenosis and increased surgical risk, as determined by the heart team, were treated by transfemoral THV implantation (age 82.7 ± 5.5 years, 67.5% female, 68.0% New York Heart Association functional class III/IV). At 30 days, mortality was 1%, disabling stroke occurred in 2.5% of patients, and New York Heart Association functional class I/II was observed in 93.0% of patients. Effective orifice area increased from 0.71 ± 0.20 cm. The herein described THV is safe and effective at 30 days with low mortality, significant improvements in hemodynamic outcomes, and low incidence of adverse events. Of particular interest is the low incidence of permanent pacemaker implantations. (Safety and Performance Study of the Edwards CENTERA-EU Self-Expanding Transcatheter Heart Valve [CENTERA-2]; NCT02458560).

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Stenosis; Cause of Death; Echocardiography; Equipment Design; Europe; Female; Follow-Up Studies; Humans; Male; Prospective Studies; Prosthesis Design; Severity of Illness Index; Time Factors; Tomography, X-Ray Computed; Transcatheter Aortic Valve Replacement; Treatment Outcome

This study aimed to evaluate the safety and performance of the TriGuard™ Embolic Deflection Device (EDD), a nitinol mesh filter positioned in the aortic arch across all three major cerebral artery take-offs to deflect emboli away from the cerebral circulation, in patients undergoing transcatheter aortic valve replacement (TAVR).. The prospective, multicentre DEFLECT I study (NCT01448421) enrolled 37 consecutive subjects undergoing TAVR with the TriGuard EDD. Subjects underwent clinical and cognitive follow-up to 30 days; cerebral diffusion-weighted magnetic resonance imaging (DW-MRI) was performed pre-procedure and at 4±2 days post procedure. The device performed as intended with successful cerebral coverage in 80% (28/35) of cases. The primary safety endpoint (in-hospital EDD device- or EDD procedure-related cardiovascular mortality, major stroke disability, life-threatening bleeding, distal embolisation, major vascular complications, or need for acute cardiac surgery) occurred in 8.1% of subjects (VARC-defined two life-threatening bleeds and one vascular complication). The presence of new cerebral ischaemic lesions on post-procedure DW-MRI (n=28) was similar to historical controls (82% vs. 76%, p=NS). However, an exploratory analysis found that per-patient total lesion volume was 34% lower than reported historical data (0.2 vs. 0.3 cm3), and 89% lower in patients with complete (n=17) versus incomplete (n=10) cerebral vessel coverage (0.05 vs. 0.45 cm3, p=0.016).. Use of the first-generation TriGuard EDD during TAVR is safe, and device performance was successful in 80% of cases during the highest embolic-risk portions of the TAVR procedure. The potential of the TriGuard EDD to reduce total cerebral ischaemic burden merits further randomised investigation.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Stenosis; Brain Ischemia; Brazil; Cardiac Catheterization; Cognition; Cognition Disorders; Diffusion Magnetic Resonance Imaging; Embolic Protection Devices; Europe; Female; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Intracranial Embolism; Male; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Risk Factors; Severity of Illness Index; Stroke; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Transcranial

The acute adaptation of the nitinol-based stent frame self expandable valve to the aortic root after deployment is poorly understood. Accordingly, this study aimed to assess the occurrence, degree and determinants of acute adaptation of the nitinol-based stent frame self-expandable valves after implantation.. This is a single-site prospective registry including patients undergoing transcatheter aortic valve replacement (TAVR) with a widely used second-generation nitinol-based self-expandable device (Evolut R, Medtronic, Minneapolis, Minnesota, USA). We measured valve diameters at three different sections: distal (aortic) level, central (annulus) level and proximal (ventricular) level. Valve expansion was estimated by the difference between the diameters calculated immediately after valve deployment (A) and at the end of the procedure (B). The absolute and relative stent changes were defined as B-A and (B-A)/B∗100, respectively. A linear regression model was performed to test the association between the degree of valve extension at each segment with baseline and procedural characteristics.. A total of 58 consecutive TAVR patients were included in this analysis, with a mean age of 82.12 ± 5.28 years. Out of the total, 46% of the patients had chronic kidney disease, 32% had diabetes and 76% had dyslipidaemia. The mean procedural time was 28.11 ± 11.6 min, with 53.45% of predilation. Postdilation was performed only in 3.5% of patients. Final stent diameters were significantly higher than those achieved immediately after valve implantation - an observation that was consistent for all the segments: 0.50 ± 0.51 mm and 2.48 ± 2.57% ( P  < 0.01) in the proximal, 0.46 ± 0.57 mm and 2.39 ± 2.96% ( P  < 0.01) in the central, as well as 0.58 ± 0.59 mm and 2.14 ± 2.14% ( P  < 0.01) at the distal segments. Postdilation significantly affected the expansion of the central segment, and, albeit not significantly, the proximal one, while no changes were observed for the distal portion of the platform.. This is the first study to have documented a significant degree of the Evolut R self-expandable valve expansion after deployment. However, further studies are required to assess the short- and long-term time course of self-expandable valve enlargement and the clinical relevance of this finding.

Topics: Aged; Aged, 80 and over; Aortic Valve; Aortic Valve Stenosis; Heart Valve Prosthesis; Humans; Prosthesis Design; Transcatheter Aortic Valve Replacement; Treatment Outcome

We report 8-year experience with vascular access complications (VACs) after percutaneous transfemoral transcatheter aortic valve implantation (TAVI). From January 2010 to January 2018, patients with iliofemoral VAC treated by an intervention following percutaneous transfemoral TAVI were included. Major VAC was defined according to the Valve Academic Research Consortium 2 classification. As first-line strategy, VACs were treated using covered nitinol stents (CS). Among 795 percutaneous transfemoral TAVI, 74 (9.3%) patients (female, 57%; 82 ± 8 years) with VAC treated by CS and/or open repair were included in this study: 59 CS cases and 15 open repair cases. Two CS patients were converted to open repair. Technical success for stent implantation was 97%. The main VAC was a persistent bleeding related to percutaneous closure device failure (72%). Thirty-day mortality in the study cohort was 5.4% (4/74), including 1 VAC-related death. One patient had postoperative lower limb ischemia successfully treated by open repair. No amputation, new-onset claudication or in-stent occlusion was recorded. Endovascular intervention using self-expandable nitinol covered stent is safe and effective as a first-line strategy for the treatment of VAC in percutaneous transfemoral TAVI. However, open repair is needed in case of unfeasibility or failure of endovascular therapy.

Topics: Aged, 80 and over; Alloys; Aortic Valve Stenosis; Coated Materials, Biocompatible; Female; Humans; Male; Postoperative Complications; Retrospective Studies; Self Expandable Metallic Stents; Transcatheter Aortic Valve Replacement

Topics: Alloys; Aortic Valve; Aortic Valve Stenosis; Bioprosthesis; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Prosthesis Design; Prosthesis Failure; Transcatheter Aortic Valve Replacement; Treatment Outcome

The use of pericardial tissue has been widely adopted in a range of cardiac surgery procedures involving the reconstruction of heart valves. Its use in aortic valve construction has been discussed in recent years by Ozaki et al. A key parameter in the optimal functioning of a fabricated valve is the sizing of the new cusps. This video tutorial demonstrates aortic valve construction using newly designed templates and forceps to facilitate sizing and enhance the symmetrical coaptation of the new cusps.

Topics: Aged; Alloys; Aortic Valve; Aortic Valve Stenosis; Female; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Pericardium; Plastic Surgery Procedures; Prosthesis Design; Prosthesis Fitting; Stents; Surgically-Created Structures; Treatment Outcome

Transcatheter aortic valve replacement has become a mainstay alternative to surgical aortic valve replacement in patients with severe aortic stenosis at high and intermediate surgical risk. Two commercially approved valves are available in the United States: balloon-expandable and self-expanding. We report here a rare complication of a self-expanding Evolut PRO (Medtronic, Minneapolis, Minnesota) valve failing to expand due to nitinol frame infolding. This results in a malopposed valve with a severe paravalvular leak, even though treated successfully with balloon valvuloplasty. It is important to recognize the characteristic angiographic signature of this complication-the "straight line" sign-and how to avoid this potentially serious complication by balloon valvuloplasty or by recapture and deployment of a new valve.

Topics: Aged; Alloys; Aortic Valve; Aortic Valve Insufficiency; Aortic Valve Stenosis; Balloon Valvuloplasty; Female; Heart Valve Prosthesis; Hemodynamics; Humans; Prosthesis Design; Prosthesis Failure; Recovery of Function; Severity of Illness Index; Transcatheter Aortic Valve Replacement; Treatment Outcome

Coronary obstruction is a rare but potentially fatal complication of transcatheter aortic valve replacement (TAVR). It can result from native leaflet or stent frame obstruction of the coronary ostia. There are reports detailing the difficulty of percutaneous coronary intervention following TAVR, but none that describe a periscope approach to access the left main ostia in the presence of a braided nitinol frame. This report describes an alternative approach to access a coronary artery when the valve stent struts are prohibitive to equipment delivery.

Topics: Aged, 80 and over; Alloys; Angioplasty, Balloon, Coronary; Aortic Valve Stenosis; Coronary Stenosis; Female; Heart Valve Prosthesis; Humans; Prosthesis Design; Severity of Illness Index; Stents; Transcatheter Aortic Valve Replacement; Treatment Outcome

Topics: Alloys; Animals; Aortic Valve Stenosis; Balloon Valvuloplasty; Bioprosthesis; Heart Valve Prosthesis; Humans; Pericardium; Prosthesis Design; Swine; Transcatheter Aortic Valve Replacement

Transcatheter aortic valve implantation (TAVI) has become a therapeutic alternative for patients presenting with severe symptomatic aortic stenosis and considered at high-surgical risk. Paravalvular leak (PVL), conduction disorders, and coronary obstruction remain unresolved procedure-related complications. The aim of this manuscript was to report the first North American experience with the ACURATE-neo. Transfemoral ACURATE-neo. The mean age was 82.7 ± 7.0 years with a mean logistic-EuroSCORE-II of 5.0 ± 2.9% and Society of Thoracic Surgeons score of 4.7 ± 2.3%. Device success was achieved in all patients. The mean distance between the aortic-annulus and the left main coronary artery ostium was 14.3 ± 3.2 mm, and eight (40%) patients had <12 mm. At 30 days, there were no deaths, conversions to surgery, or major procedure-related complications. New-pacemaker implantation was required in one (5.3%) patient. ACURATE-neo. The present initial North American experience shows that the ACURATE-neo

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Stenosis; Bioprosthesis; Female; Heart Valve Prosthesis; Hemodynamics; Humans; Male; Ontario; Prosthesis Design; Recovery of Function; Self Expandable Metallic Stents; Severity of Illness Index; Time Factors; Transcatheter Aortic Valve Replacement; Treatment Outcome

Our aim was to describe our experience with the use of an ePTFE-covered nitinol self-expanding stent graft (GORE® VIABAHN® Endoprosthesis, Gore Medical, USA) placed in the common femoral artery for the treatment of suture-mediated pre-closure device failure following transcatheter aortic valve replacement (TAVR).. Access site-related vascular complications (VC) following sheath removal related to pre-closure device failure during TAVR are common and treatment options may vary.. We performed an observational study on a series of consecutive patients who underwent TAVR between 2013 and 2015.. Included were 25 patients at a mean (±SD) age of 82±9. Failure of the closure device resulted in overt bleeding in 19 patients, dissection or no flow in 5 patients, and angiographic pseudoaneurysm in 1. Overall 29 stents were deployed with diameters ranging from 8 to 11mm and a length of 50mm (26, 90%). All stent-graft deployments achieved complete hemostasis of the arteriotomy site and resulted in normal flow to the distal vessels. None of the patients required open surgical repair. The mean hemoglobin drop was 2.6±1.3g/dl. Blood transfusions were used in 15 (60%) patients. Acute kidney injury occurred in 4 (16%) patients, none of whom was treated with dialysis. Length of hospital stay was 9±5days. All patients survived during a 30-day follow-up period, and none had VC related to the stented site.. The use of an ePTFE-covered Nitinol self-expanding stent graft is a feasible, safe, and effective treatment modality for access site-related VC following TAVR.. The use of an ePTFE-covered nitinol self-expanding stent graft placed in the common femoral artery for the treatment of suture-mediated pre-closure device failure following transcatheter aortic valve replacement (TAVR) is described in 25 patients. Its use was found to be feasible, safe, and an effective treatment modality for access site-related vascular complications following TAVR.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Stenosis; Cardiac Catheterization; Female; Femoral Artery; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Male; Stents; Transcatheter Aortic Valve Replacement; Treatment Outcome

Surgical sutureless aortic valves have the potential for shorter procedural times and could benefit patients with increased risk. The Enable (Medtronic Inc, Minneapolis, Minn) valve is a bioprosthesis housed in a Nitinol cage allowing folding and deployment once implanted. We aimed to evaluate the early clinical and echocardiographic results with the Enable valve.. Patients with aortic stenosis, Society of Thoracic Surgeons score greater than 5.0%, the need for combined procedures, and frailty were considered for Enable implantation.. Between August 2012 and October 2014, 63 patients underwent implantation of the Enable valve (Medtronic Inc, Minneapolis, Minn). Thirty patients underwent isolated aortic valve replacement. Combined procedures were aortic valve replacement/coronary artery bypass grafting (26), aortic valve replacement/mitral valve repair (2), aortic valve replacement/mitral valve repair/coronary artery bypass grafting (2), and aortic valve replacement/ascending aortic graft (3). Predicted Society of Thoracic Surgeons score was 8.06 ± 7.73 (0.94-41.30). Implant success was 100%. Mean crossclamp time for isolated aortic valve replacement was 44 ± 14 minutes (30-91). Thirty-day mortality was 1.6% (1/63), and late mortality was 3.2% (2/62). No mortality was valve related. Intraoperative need for revision was 6.3% (4/63). Early migration requiring reoperation occurred in 1.6% of patients (1/63). Postoperative indexed aortic valve area was 1.08 ± 0.22 cm(2)/m(2), and peak and mean gradients were 17 ± 7 mm Hg and 9 ± 4 mm Hg, respectively. The rate of complications was as follows: pacemaker 3.1% (2/63), transient ischemic attack 1.6% (1/63), other thromboembolic events 0%, bleeding 0%, and endocarditis 0%. Mean follow-up was 10 ± 8 months. At latest follow-up, 61 patients were in New York Heart Association class I. Moderate or severe aortic regurgitation did not develop in any patients in the follow-up period.. The Enable bioprosthesis is an acceptable alternative to conventional aortic valve replacement in higher-risk patients. The early hemodynamic performance seems favorable.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Stenosis; Bioprosthesis; Cardiac Catheterization; Echocardiography, Doppler, Color; Female; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Hemodynamics; Humans; Male; Middle Aged; Prosthesis Design; Quebec; Retrospective Studies; Risk Assessment; Risk Factors; Suture Techniques; Time Factors; Treatment Outcome

Transapical transcatheter aortic valve implantation (TA-TAVI) is the recognized first choice surgical TAVI access. Expansion of this well-established treatment modality with subsequent broader patient inclusion has accelerated development of second-generation TA-TAVI devices. The Swiss ACURATE TA Symetis valve allows for excellent anatomical positioning, resulting in a very low incidence of paravalvular leaks. The self-expanding stent features an hourglass shape to wedge the native aortic valve annulus. A specially designed delivery system facilitates controlled release aided by tactile operator feedback. The ACURATE TA valve made of three native porcine non-coronary leaflets has received CE approval in September 2011. Since then, this valve is the third most frequently implanted TAVI device with over 1200 implants in Europe and South America. Results from the Symetis ACURATE TA™ Valve Implantation ('SAVI') Registry showed a procedural success rate of 98.0% and a survival rate of 93.2% at 30 days. This presentation provides technical considerations and detailed procedural aspects of device implantation.

Topics: Aged; Aged, 80 and over; Alloys; Angiography; Aortic Valve; Aortic Valve Stenosis; Bioprosthesis; Cardiac Catheterization; Clinical Trials as Topic; Female; Heart Valve Prosthesis; Humans; Intraoperative Care; Male; Prosthesis Design; Prosthesis Fitting; Severity of Illness Index; Stents; Switzerland; Transcatheter Aortic Valve Replacement; Treatment Outcome

Topics: Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Insufficiency; Aortic Valve Stenosis; Bioprosthesis; Cardiac Catheterization; Femoral Artery; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Incidence; Prosthesis Design; Treatment Outcome

Transcatheter aortic valve implantation is a widely performed procedure for treatment of symptomatic severe aortic stenosis. According to the current literature, major stroke has been reported as occurring in 3-6% of patients during the first 30 days following valve implantation. Several pathological mechanisms may be involved in the development of periprocedural ischaemic stroke with the majority being due to thromboembolism and atheroembolism. One approach to reduce the incidence of procedural cerebral thromboembolic events is the use of cerebral protection devices, either deflecting (Embrella, TriGuard) or capturing (Claret, Embol-X) embolic material. We decided to review the current evidence on this important issue focusing on the four cerebral protection devices currently available.

Topics: Alloys; Aortic Valve; Aortic Valve Stenosis; Cardiac Catheterization; Contraindications; Equipment and Supplies; Equipment Design; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Incidence; Risk Factors; Stroke; Thromboembolism; Treatment Outcome

Topics: Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Insufficiency; Aortic Valve Stenosis; Balloon Valvuloplasty; Bioprosthesis; Feasibility Studies; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Incidence; Prosthesis Design; Stents; Treatment Outcome

Transcatheter aortic valve implantation for patients with severe aortic stenosis at a high-operative risk has been demonstrated to improve mortality compared to standard medical therapy. Registry data and the PARTNER trial have shown a significant risk of stroke (3-5%) following the procedure. Studies using cerebral diffusion-weighted magnetic resonance imaging have suggested the mechanism of stroke to be multiple small embolic infarcts, possibly from aortic atheroma dislodged during the movement of the valve and its apparatus around the thoracic aorta. The incidence of these infarcts is higher than clinically apparent. The Medtronic CoreValve (Medtronic, Minneapolis, Minnesota) prosthesis is a self-expanding nitinol frame with porcine valve, whose deployment is achieved by the retraction of the delivery catheter. Potential complications of this method include valve mal-positioning and dislocation. The partially deployed valve may then be resheathed following retraction back into the descending aorta and subsequently redeployed. We present two such cases with evidence of both "silent" and clinically evident cerebral infarction.

Topics: Aged, 80 and over; Alloys; Aortic Valve Stenosis; Bioprosthesis; Cardiac Catheterization; Cardiac Catheters; Cerebral Infarction; Diffusion Magnetic Resonance Imaging; Female; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Intracranial Embolism; Prosthesis Design; Severity of Illness Index

To ascertain incidence and predictors of new permanent pacemaker (PPM) following transcatheter aortic valve implantation (TAVI) with the self-expanding aortic bioprosthesis.. TAVI with the Medtronic Corevalve (MCV) Revalving System (Medtronic, Minneapolis, MN) has been associated with important post-procedural conduction abnormalities and frequent need for PPM.. Overall, 73 consecutive patients with severe symptomatic AS underwent TAVI with the MCV at two institutions; 10 patients with previous pacemaker and 3 patients with previous aortic valve replacement were excluded for this analysis. Clinical, echocardiographic, and procedural data were collected prospectively in a dedicated database. A standard 12-lead ECG was recorded in all patients at baseline, after the procedure and predischarge. Decision to implant PPM was taken according to current guidelines. Logistic multivariable modeling was applied to identify independent predictors of PPM at discharge.. Patients exhibited high-risk features as evidenced by advanced age (mean = 82.1 ± 6.2 years) and high surgical scores (logistic EuroSCORE 23.0 ± 12.8%, STS score 9.4 ± 6.9%). The incidence of new PPM was 28.3%. Interventricular septum thickness and logistic Euroscore were the baseline independent predictors of PPM. When procedural variables were included, the independent predictors of PPM were interventricular septum thickness (OR 0.52; 95% CI 0.32-0.85) and the distance between noncoronary cusp and the distal edge of the prosthesis (OR 1.37; 95% CI 1.03-1.83).. Conduction abnormalities are frequently observed after TAVI with self-expandable bioprosthesis and definitive pacing is required in about a third of the patients, with a clear association with depth of implant and small interventricular septum thickness.

Topics: Aged; Aged, 80 and over; Alloys; Analysis of Variance; Aortic Valve Stenosis; Bioprosthesis; Cardiac Catheterization; Cardiac Pacing, Artificial; Cohort Studies; Echocardiography, Doppler; Electrocardiography; Female; Follow-Up Studies; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Italy; Logistic Models; Male; Minimally Invasive Surgical Procedures; Multivariate Analysis; Postoperative Complications; Predictive Value of Tests; Preoperative Care; Prospective Studies; Prosthesis Design; Risk Assessment; Severity of Illness Index; Survival Rate; Time Factors; Treatment Outcome

Both retrograde femoral and subclavian artery catheterization techniques have been described as the most common methods for the implantation of the Medtronic CoreValve percutaneous aortic valve (Medtronic Inc, Minneapolis, Minn). The subclavian artery has been shown to be a safe and effective alternative access route in patients with unfavorable femoral access. Of the patients who are identified as candidates for subclavian artery access, a subset possess a patent left internal thoracic artery to left anterior descending artery. This patent left internal thoracic artery presents an additional anatomic and clinical variable that must be taken into consideration to ensure procedural safety and efficacy. We describe the Medtronic CoreValve percutaneous aortic valve implantation using the subclavian arterial approach in patients with a patent left internal thoracic artery and report our study's findings.. The CoreValve percutaneous aortic valve is a self-expandable nitinol-based frame with a porcine pericardial valve. The subclavian access was created by a small infraclavicular surgical incision to expose the artery. Rapid ventricular pacing was used to reduce cardiac output to perform the balloon aortic valvuloplasty via a 12F sheath inserted into the subclavian artery. An 18F sheath was then inserted into the artery down into the ascending aorta and used for introduction of the delivery catheter and implantation of the percutaneous aortic valve.. With the use of this method, 19 patients (76 ± 13 years) whose surgical risk was deemed excessive because of severe comorbidity and in whom transfemoral catheterization was considered unfeasible or at risk of severe complications have received implants. Subclavian artery or left internal thoracic artery injury did not occur in any patient. Two deaths occurred. One patient died of right coronary artery occlusion during the procedure, and one patient died 48 hours after the procedure as the result of a tamponade after the temporary pacemaker wire ablation.. This initial experience suggests that subclavian transarterial aortic valve implantation in patients with a patent left internal thoracic artery to left anterior descending artery is feasible and safe with satisfactory short-term outcomes.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve Stenosis; Axillary Artery; Balloon Valvuloplasty; Bioprosthesis; Cardiac Catheterization; Feasibility Studies; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Internal Mammary-Coronary Artery Anastomosis; Middle Aged; Prospective Studies; Prosthesis Design; Severity of Illness Index; Subclavian Artery; Time Factors; Treatment Outcome; Vascular Patency

The optimal clinical protocol to detect fractures of transcatheter aortic valves is unknown. To the best of our knowledge, there are no published reports describing stent or frame fractures following transcatheter aortic valve implantation. The purpose of this study is two-fold: (1) to determine the optimal fluoroscopic protocol to identify potential fractures of the Medtronic CoreValve frame; and (2) to implement this protocol in the analysis of the fluoroscopic films of patients implanted with the CoreValve device with 1-year minimum follow-up.. Considering the resolution of fluoroscopy (approximately 0.2 mm), we used a 0.2 mm diamond-cutter to create a single fracture in a single strut of two CoreValve frames. An intact CoreValve prosthesis was used as control. These prostheses were subsequently implanted in post-mortem heart specimens. A protocol involving still frames and rotational (left-right and cranial-caudal) fluoroscopic imaging was then applied to the heart specimens. The experimentally induced fractures were detectable on the rotational cine runs (left-right and cranial-caudal); in some of the fixed acquisition sequences, however, the fractures were undetectable. The fluoroscopic protocol was retrospectively applied to the films of 58 patients who underwent implantation with the CoreValve System between October 2005 and August 2008 and had at least 1-year follow-up. The mean and median follow-up times were 22 months and 24 months, respectively (range 12 to 36 months). Rotational cine films (only left-right lateral) were available in 39 patients (60%). No frame fractures of the CoreValve frame were identified.. Rotational cine runs in the left-right and cranial-caudal directions should be mandatory in the clinical assessment of the structural integrity of the CoreValve frame. No frame fractures were identified in 58 patients implanted with the Medtronic CoreValve device with 2-year mean follow-up.

Topics: Alloys; Aortic Valve Stenosis; Clinical Protocols; Equipment Failure Analysis; Fluoroscopy; Follow-Up Studies; Heart Valve Prosthesis; Humans; Materials Testing; Prosthesis Failure; Retrospective Studies; Time Factors; Tomography, X-Ray Computed

The use of minimally invasive techniques for aortic valve replacement (AVR) may be limited for severely calcified and degenerated stenotic aortic valves. A quick resection leaving a defined geometry would be advantageous. Therefore, a new minimally invasive resection tool was developed, using rotating foldable cutting edges. This report describes the first experimental in-vitro results of measuring turning moment and forces during cutting of test specimens. Nitinol cutting edges were mounted on a simplified version of the resection instrument. The instrument shaft was combined with an exchangeable gear (1:3.71 vs. 1:5.0), and an exchangeable screw thread for accurate feed motion (0.35 mm or 0.5 mm) was implemented. Furthermore, the option of an added stabilisation body (SB) to prevent strut-torsion during cutting was tested. Tests were performed upon specially designed test specimens, imitating native calcified aortic valves. Resection was successful in all 60 samples (12 samples for each of the five configurations). Mean resection time ranged from 18.7+/-1.0 s (gear 1:3.71, screw thread 0.5, with SB) to 29.3+/-4.6 s (gear 1:5, screw thread 0.35, with SB), mean maximum turning moment ranged from 2.1+/-0.2 Nm (gear 1:3.71, screw thread 0.35, with SB) to 2.8+/-0.4 (gear 1:5, screw thread 0.35, with SB), mean maximum force from 36.0+/-11.3 N (gear 1:3.71, screw thread 0.35, with SB) to 56.3+/-10.5 N (gear 1:3.71, screw thread 0.5, without SB) and mean number of required rotations from 41.3+/-2.9 (gear 1:3.71, screw thread 0.5, with SB) to 59.1+/-3.7 (gear 1:3.71, screw thread 0.35, without SB). In summary, the positive influence of the stabilisation body could be shown. Combining the right parameters, it is possible to limit maximum cutting forces to F(max)<50 N and maximum turning moments to M(max)< 3.0 N.

Topics: Alloys; Aortic Valve; Aortic Valve Stenosis; Equipment Design; Heart Valve Prosthesis Implantation; Humans; Materials Testing; Minimally Invasive Surgical Procedures; Time Factors

Percutaneous aortic valve replacement is a new less-invasive alternative for high-risk surgical candidates with aortic stenosis. However, the clinical experience is still limited, and the currently available 'first-generation devices' revealed technical shortcomings, such as lack of repositionability and presence of paravalvular leakages. We report the first-in-man experience with the new self-expanding Lotus Valve prosthesis composed of a nitinol frame with implemented bovine pericardial leaflets which is designed to address these issues, being repositionable and covered by a flexible membrane to seal paravalvular gaps. We implanted this prosthesis in a 93-year old patient presenting with severe symptomatic aortic stenosis (valve area: 0.6 cm(2)). Surgical valve replacement had been declined due to comorbidities.. We used a retrograde approach for insertion of the 21-French Lotus catheter loaded with the valve prosthesis via surgical cut-down to the external iliac artery. Positioning of the valve was guided by transesophageal echo and supra-aortic angiograms. The prosthesis was successfully inserted and deployed within the calcified native valve. Echocardiography immediately after device deployment showed a significant reduction of the transaortic mean pressure gradient (32 to 9 mmHg; final valve area 1.7 cm(2)) without evidence of residual aortic regurgitation. The postprocedural clinical status improved from NYHA-IV to NYHA-II. These results remained unchanged up to the 3 month follow-up.. Successful percutaneous aortic valve replacement can be performed using the new self-expanding and repositionable Lotus valve for treatment of high-risk patients with aortic valve stenosis. Further studies are mandatory to assess device safety and efficacy in larger patient populations.

Topics: Aged, 80 and over; Alloys; Animals; Aortic Valve Stenosis; Aortography; Bioprosthesis; Cattle; Echocardiography, Transesophageal; Feasibility Studies; Female; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Minimally Invasive Surgical Procedures; Pericardium; Pilot Projects; Prosthesis Design; Radiography, Interventional; Severity of Illness Index; Tomography, X-Ray Computed; Treatment Outcome

Topics: Alloys; Animals; Aortic Valve Stenosis; Bioprosthesis; Cattle; Diffusion of Innovation; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Minimally Invasive Surgical Procedures; Pericardium; Prosthesis Design; Radiography, Interventional; Severity of Illness Index; Treatment Outcome

To study the effects of nitinol alloy stent in the treatment of atherosclerotic arterial stenosis, eight miniature pigs were subject to abdominal aortic balloon denudation and high-fatty food. Then 8 nitinol alloy stents were implanted into each abdominal aortas of pigs. The pigs were equally divided into two groups. One group was given captopril (3 mg/kg/d). All animals were sacrified for pathological examination 6 to 10 months after stent implantation. The degree of arterial intima proliferation in the areas of stent implantation not significantly different from that of areas of balloon denudation alone; the atherosclerotic lesions were found at the arterial surface of stent implantation sites. The intima layer was rich in smooth muscle cells, with atherosclerotic plaque formed around the stent wire. On the other hand, significant decrease in arterial intima proliferation was found in group II with no atherosclerotic plaque. The arterial stenosis resulting from atherosclerotic lesion could not be prevented by implantation of intravascular stent, and on the contrary, the mechanical stress of stent wire might worsen the atherosclerosis. Captopril might impede the development of atherosclerotic stenosis after stent implantation.

Topics: Alloys; Angiotensin-Converting Enzyme Inhibitors; Animals; Aorta, Abdominal; Aortic Valve Stenosis; Arteriosclerosis; Captopril; Stents; Swine; Swine, Miniature