Prosthesis Size Research Articles

Impact of type and size of annuloplasty prosthesis on hemodynamic status after mitral valve repair for degenerative disease

ObjectiveThe aim of this study is to evaluate mitral valve hemodynamics after mitral valve repair for degenerative disease, and seek the impact of type/size of annuloplasty prosthesis on resting cardiac hemodynamics. MethodsBetween October 2012 and June 2019, 301 patients underwent isolated mitral valve repair for degenerative disease were enrolled. Correlation between postoperative mitral hemodynamics and type/size of annuloplasty prosthesis was evaluated. ResultsThere were significant correlations between annuloplasty size and peak velocity (r = −0.41, p < 0.001), peak transmitral pressure gradient (TMPG) (r = −0.40, p < 0.001), mean TMPG (r = −0.41, p < 0.001), effective orifice area (EOA) (r = 0.26, p < 0.001), and pulmonary artery systolic pressure (r = −0.15, p = 0.010). In patients with larger annuloplasty prostheses (≥30 mm), the type of annuloplasty prosthesis (band or ring) did not influence the mitral hemodynamics, however, mean TMPG was significantly greater in patients with a full ring (2.9 mmHg [2.1–3.7] vs. 4.0 mmHg [2.8–5.0], p < 0.001) in patients with smaller annuloplasty (<30 mm). Left ventricular ejection fraction and stroke volume were significantly associated with an increase of TMPG (r = 0.14, p = 0.016 and r = 0.24, p < 0.001). ConclusionsA larger partial band had the potential to improve mitral hemodynamics after mitral repair for degenerative disease. However, echocardiographic mitral hemodynamics was influenced by LV function. Therefore, a more accurate method is required to elucidate the true impact of mitral repair on hemodynamics.

Non-contrast MRI protocol for TAVI guidance: quiescent-interval single-shot angiography in comparison with contrast-enhanced CT

ObjectivesTo prospectively compare unenhanced quiescent-interval single-shot MR angiography (QISS-MRA) with contrast-enhanced computed tomography angiography (CTA) for contrast-free guidance in transcatheter aortic valve intervention (TAVI).MethodsTwenty-six patients (mean age 83 ± 5 years, 15 female [58%]) referred for TAVI evaluation underwent QISS-MRA for aortoiliofemoral access guidance and non-contrast three-dimensional (3D) “whole heart” MRI for prosthesis sizing on a 1.5-T system. Contrast-enhanced CTA was performed as imaging gold standard for TAVI planning. Image quality was assessed by a 4-point Likert scale; continuous MRA and CTA measurements were compared with regression and Bland-Altman analyses.ResultsQISS-MRA and CTA-based measurements of aortoiliofemoral vessel diameters correlated moderately to very strong (r = 0.572 to 0.851, all p ≤ 0.002) with good to excellent inter-observer reliability (intra-class correlation coefficient (ICC) = 0.862 to 0.999, all p < 0.0001) regarding QISS assessment. Mean diameters of the infrarenal aorta and iliofemoral vessels differed significantly (bias 0.37 to 0.98 mm, p = 0.041 to < 0.0001) between the two modalities. However, inter-method decision for transfemoral access route was comparable (κ = 0.866, p < 0.0001). Aortic root parameters assessed by 3D whole heart MRI strongly correlated (r = 0.679 to 0.887, all p ≤ 0.0001) to CTA measurements.ConclusionQISS-MRA provides contrast-free access route evaluation in TAVI patients with moderate to strong correlations compared with CTA and substantial inter-observer agreement. Despite some significant differences in minimal vessel diameters, inter-method agreement for transfemoral accessibility is strong. Combination with 3D whole heart MRI facilitates unenhanced TAVI guidance.Key Points• QISS-MRA and CTA inter-method agreement for transfemoral approach is strong.• QISS-MRA is a very good alternative to CTA and MRA especially in patients with Kidney Disease Outcomes Quality Initiativestages 4 and 5.• Combination of QISS-MRA and 3D “whole heart” MRI facilitates fully unenhanced TAVI guidance.

One-year outcome with a bovine pericardial valve.

ObjectivesTo evaluate the safety and effectiveness of a novel surgical bovine pericardial valve for aortic and mitral valve replacements.MethodsBetween March 2016 and October 2017, 197 patients (mean age, 66.9 ± 4.9 years; 40.6% were women) underwent aortic valve replacement and mitral valve replacement and were implanted with the Cingular bovine pericardial valve (Shanghai Cingular Biotech Corporation, Shanghai, China) in a prospective, multicenter, single-arm trial in China. A total of 161 aortic and 49 mitral prostheses were implanted. Patients were followed up to 1 year. The primary end point was the 1-year overall rate of valve-related complications, including thromboembolic event, valve thrombosis, major hemorrhage event, major perivalvular leak, and prosthetic valve endocarditis.ResultsThe 1-year overall rate of valve-related complications was 0.5% (95% confidence interval, 0.1%-3.7%). The 1-year survival was 96.4%. The mean gradient and effective orifice area for aortic prostheses at 1 year postoperatively were 12.8 ± 4.4 mm Hg and 1.9 ± 0.3 cm2, respectively. Particularly, the mean gradients and effective orifice area for 19 mm and 21 mm sizes of aortic prostheses at 1 year were 17.0 ± 3.8 mm Hg and 1.6 ± 0.2 cm2, 13.1 ± 4.0 mm Hg and 1.8 ± 0.1 cm2, respectively. Patient–prosthesis mismatch occurred in only 1.3% patients for aortic valve implantation at 1 month. No structural valve deterioration and no endocarditis occurred.ConclusionsThe Cingular bovine pericardial valve was safe and effective for surgical aortic and mitral valve replacement. The 1-year rate of valve-related complications was very low. Early hemodynamic performance was excellent even for the small aortic root.

DYNAMIC CONFORMATIONAL CHANGES OF THE LEFT VENTRICULAR OUTFLOW TRACT COMPARED TO THE AORTIC ANNULUS AND IMPLICATIONS ON TRANSCATHETER AORTIC VALVE SELECTION AND SIZING

ECG-gated computed tomography angiography (CTA) has become the standard for assessing the aortic root prior to transcatheter aortic valve replacement (TAVR). Current techniques rely primarily on systolic annular sizing for the selection and sizing of valve prostheses. We sought to evaluate the

Role of computed tomography in transcatheter aortic valve implantation and valve-in-valve implantation: complete review of preprocedural and postprocedural imaging.

: Since 2002, transcatheter aortic valve implantation (TAVI) has revolutionized the treatment and prognosis of patients with aortic stenosis. A preprocedural assessment of the patient is vital for achieving optimal outcomes from the procedure. Retrospective ECG-gated cardiac computed tomography (CT) today it is the gold-standard imaging technique that provides three-dimensional images of the heart, thus allowing a rapid and complete evaluation of the morphology of the valve, ascending aorta, coronary arteries, peripheral access vessels, and prognostic factors, and also provides preprocedural coplanar fluoroscopic angle prediction to obtain complete assessment of the patient. The most relevant dimension in preprocedural planning of TAVI is the aortic annulus, which can determine the choice of prosthesis size. CT is also essential to identify patients with increased anatomical risk for coronary artery occlusion in Valve in Valve (ViV) procedures.Moreover, CT is very useful in the evaluation of late complications, such as leakage, thrombosis and displacements. At present, CT is the cornerstone imaging modality for the extensive and thorough work-up required for planning and performing each TAVI procedure, to achieve optimal outcomes. Both the CT procedure and analysis should be performed by trained and experienced personnel, with a radiological background and a deep understanding of the TAVI procedure, in close collaboration with the implantation team. An accurate pre-TAVI CT and post-processing for the evaluation of all the points recommended in this review allow a complete planning for the choice of the valve dimensions and type (balloon or self-expandable) and of the best percutaneous access.

Effects of hemodynamic conditions and valve sizing on leaflet bending stress in self-expanding transcatheter aortic valve: An in vitro study.

Transcatheter aortic valve (TAV) replacement has become a viable alternative to surgery for high and intermediate risk patients with severe aortic stenosis. This technology may extend to the younger and lower risk patients. In this population, long-term durability of the TAV is key. Increased leaflet mechanical stress is one of the main determinants of valve structural deterioration. This in vitro study aims at evaluating leaflet bending stress (LBS) in the self-expanding TAV for different valve sizes, stroke volumes (SV), and degrees of valve oversizing (OS). Three different sizes (23, 26, and 29 mm) of CoreValve (CV) were tested on a pulse duplicator in annulus size ranging from 17 to 26 mm. Leaflet bending stress and bending of the leaflet coaptation line in diastole pinwheeling index (PI) were measured using high-speed camera imaging (1000 images/s). For each given CV and annulus size, geometric orifice area (GOA) increased significantly with OS (P<.001) and SV (P=.001). LBS decreased with increasing prosthesis size and aortic annulus (AA) size while increasing with SV (P<.03). The largest value of peak LBS (3.79 MPa) was obtained with the CV 23 mm in AA of 17 mm (%OS=35%), SV 90 mL and the smallest value (0.99 MPa) for the CV 29 mm in AA of 26 mm (%OS=12%), SV 30 mL. On multivariable analysis, LBS increased independently with larger OS, smaller AA size and higher SV. The PI increased with decreasing AA size and increasing OS. Moderate valve OS, such as generally used for transcatheter aortic valve implantation, is associated with increased LBS during valve opening and closing, especially in small annuli. Hence, TAV OS may negatively impact long-term valve durability.

A study of morphometric analysis of distal end of femur and its clinical importance

Introduction: Femur is an important component of the lower kinetic series and functions as a weightbearing bone. The distal end of femur’s morphometry is vital in the designing the implants for total joint arthroplasty. The design of prosthesis is based on morphometry of the distal end of the femur. To ensure the early mobility as well as fewer complications after total knee arthroplasty, the designing of prosthesis based on morphometric values of distal end of femur plays a key role. Objectives: To study the morphometric data of the distal end of femur. To compare the morphometric data between right and left femur. Materials and Methods: One hundred and eighty femurs of unidentified sex were measured for the width of Bicondylar, the maximum medial and lateral condyle anteroposterior length, the total transverse distance of the medial and lateral condyle, and the width of intercondylar notch. Results: The average bicondylar width of entire femur sample was 71.32 5.91 mm, mean anteroposterior diameter of medial and lateral condyle were 56.12 4.51 mm and 56.85 4.31 mm respectively. The medial and lateral condyle mean transverse distance of was 28.33 3.49 mm and 30.7 3 3.21 mm respectively. It was found that the mean intercondylar notch width was 21.62 2.92 mm. In this study, there were no statistically significant parameters between right and left femur. Conclusion: The data obtained from this study will help the biomedical engineers to design the knee replacement prosthesis of suitable size for Indian patients undergoing knee replacement operations. Keywords: Morphometry, Distal end of Femur, Knee prosthesis, Intercondylar notch, Bicondylar width.

Effect of low contrast medium-dose CTA on device sizing and access vessel assessment for TAVR

PurposeChronic kidney disease (CKD) is prevalent in transcatheter aortic valve replacement (TAVR) candidates, leading to concerns regarding contrast medium (CM) safety. We evaluated (a) the impact of low-CM imaging on pre-TAVR measurements and (b) postcontrast acute kidney injury (PC-AKI) prevalence after dual-source computed tomography (DSCT) in TAVR candidates. MethodsAll TAVR candidates with CKD (SCr≥1.5 mg/dL) who underwent weight-based low-CM, low-pitch helical 3rd-generation DSCT in a one-year period were included, and matched to standard-CM, non-CKD controls (N = 50). Image quality (IQ) and pre-TAVR measurement interobserver variability were evaluated. Renal function change and PC-AKI were studied in the entire TAVR cohort, irrespective of scan mode (N = 153). ResultsLow-CM in CKD (N = 25) was performed with median 68 mL CM [52–87], 90 kV [80–90] and SCr 1.6 mg/dL [1.5–1.9], and standard-CM without CKD with median 116 mL CM [96–134], 100 kV [90–110] and SCr 1.0 mg/dL [0.9–1.1](P < 0.00). Low-CM IQ was good, though lower compared with standard-CM (P < 0.02). Interobserver measurement reliability was excellent (ICCs>0.85). Interobserver-agreement was lower in low-CM, causing prosthesis size disagreement in 5/25 (kappa-0.73) versus 0/25 with standard-CM (kappa-1.00), and transfemoral eligibility disagreement in 4/25 (kappa-0.68) versus 2/25 (kappa-0.84), respectively. Mean 1-month SCr-change in the low-CM TAVR cohort (N = 35) was −1 % [−12 to +7 %] and in standard-CM (N = 118) 0 % [−8 to +10 %](P > 0.3). PC-AKI occurred in none. ConclusionLow-CM third-generation-DSCT achieves good IQ in TAVR candidates with CKD, and seems safe, with no apparent renal function deterioration or prevalence of PC-AKI. However, standard-CM protocols in non-CKD patients provide higher measurement reproducibility. Low-CM protocols should therefore be reserved for patients at high risk for PC-AKI.

Malleostapedotomy: Recent Innovations and Surgical Outcomes

Malleostapedotomy (MS) is a challenging otologic surgical technique involving complex anatomic relationships and nuanced technical considerations. Over the past few decades, MS has been refined by development of customized prostheses and enhanced understanding of relevant ossicular anatomic dimensions. This article presents outcomes with a self-crimping angulated malleostapedotomy piston and reviews recent published advancements relevant to MS surgery. Excellent results are reported with a self-crimping angulated nitinol piston including AB gap closure < 20 dB in the majority of cases and < 10 dB in many cases. Innovations in surgical technique include consideration for shifting the crimp site to the malleus neck, possible repositioning of the malleus, and use of an endoscope. Prosthesis sizing may be optimized by specialized instruments or preoperative 3D radiologic imaging. Malleostapedotomy remains a viable option for management of stapes fixation when traditional incus-grip techniques are not possible. Ongoing innovation in technique and prosthesis may further advance hearing outcomes in to the future.

Radiologic Results of Three-Dimensional Templating for Total Shoulder Arthroplasty.

BackgroundThe purpose of this study was to evaluate the radiologic results of total shoulder arthroplasty using computerized three-dimensional (3D) templating in preoperative planning.MethodsTen patients who underwent total shoulder arthroplasty using 3D templating preoperatively were enrolled in this study. A specialized computer program was used to reconstruct the 3D images of the shoulder from the computed tomographic images. The 3D images of various sizes of prostheses were used as the template in surgical planning of the shoulder arthroplasty. The size of the glenoid, humeral head, and stem measured in 3D templating were compared with those used in actual operation. Anatomical parameters, such as humeral head size, radius of curvature, and greater tuberosity to humeral head distance of the replaced shoulder, were measured and compared with those of the contralateral normal shoulder.ResultsThe agreement rates between the glenoid size, head size, head thickness, and stem size estimated preoperatively by 3D templating and those measured in operation were 100%, 100%, 100%, and 80%, respectively. The difference in humeral head size, radius of curvature, and greater tuberosity to humeral head distance between the replaced shoulder and contralateral shoulder was 1.31 mm, 0.87 mm, and 1.17 mm, respectively.ConclusionsIn total shoulder arthroplasty, 3D templating seems to enable accurate prediction of sizes of the prostheses to be inserted and thus replication of normal anatomy.

Evolution of concomitant moderate and moderate to severe functional mitral regurgitation, following aortic valve surgery for severe aortic stenosis

Background/Aim. Functional mitral regurgitation (FMR) is a common entity in patients with aortic stenosis (AS) undergoing aortic valve replacement (AVR). The aim of this study was to examine evolution of moderate and moderate to severe FMR after an isolated AVR, to identify prognostic indicators for persistent MR postoperatively, and to offer the recommendation regarding surgical intervention for moderate and moderate to severe FMR at the time of AVR for AS. Methods. We retrospectively reviewed 39 consecutive patients with moderate and moderate to severe FMR at the time of isolated AVR from January 2007 to December 2013. We collected preoperative and postoperative echocardiographic data to determine the evolution of FMR after AVR. Patients were divided into the persistent (n = 14) and improved FMR group (n = 25). Secondary division was into the prosthesis-patient mismatch (PPM, n = 7) and non prosthesis-patient mismatch group (non PPM, n = 32 patients). Late follow-up echocardiography was completed in 100% (39/39) of patients. Results. FMR improved postoperatively (MR ? 2+) in 64% (25/39) of patients, while 36% (14/39) of patients had persistent MR ? 2). In comparison to the persistent group, the patient with improved FMR had significant decrease in the left ventricular enddiastolic diameter, left ventricular end-systolic diameter, posterior wall and septum thickness postoperatively. The same indicators of reverse remodeling were found in the non PPM group in comparison to the PPM group. The incidence of postoperative FMR improvement was higher in the non PPM group (65.6%, p = 0.001) in comparison to the PPM group (42.9%, p = 0.125). The mean follow-up duration was 39.5 ? 23.5 months. Conclusion. In accordance with previous studies, this study also showed improvement in FMR following AVR surgery. Improvement in MR degree was associated with echocardiographic parameters of reverse left ventricular remodeling. Conservative approach is advisable in patients with moderate and moderate to severe FMR, believing that repair or replacement is unnecessary at the time of AVR for severe AS. PPM could prevent downgrading of FMR, stressing out the importance of choosing the prosthesis of adequate size.

The accuracy of pre-operative digital templating in total hip arthroplasty performed in a low-volume, resource-constrained orthopaedic unit

Aims: Total hip arthroplasty (THA) is considered one of the most successful surgical procedures in modern medicine. The success of THA is well documented, and includes high patient satisfaction rates, low morbidity rates and cost-effective surgery. Most publications come from THA performed in high-volume arthroplasty units, done in high-income countries. Limited data is available on THA performed in low-volume, low-income countries. The aim of this study was to evaluate the accuracy of digital templating in a low-volume, resource constrained orthopaedic unit from 2016 to 2017. We introduced a standardised hip radiography programme, followed by a stepwise pre-operative templating method. We compared the implant sizes inserted during THA with the templated sizes determined pre-operatively. This was to deduct whether digital templating in a low volume arthroplasty unit is accurate and of the same value as digital templating done in a high-volume unit. Methods: A descriptive retrospective study was conducted on all patients who received elective primary uncemented THA in a low-volume, resource-constrained orthopaedic unit. Pre-operative radiographs were done according to guidelines published by Scheerlinck followed by pre-operative templating using the Impax Orthopaedic tools® software and a stepwise technique described by Bono. Implanted prosthesis sizes, as recorded in operation notes, were retrospectively compared to pre-operative templating. Results: A total of 56 participants were included (30 females, 26 males), with a mean age of 55.5 (32–78) years. On the acetabular side, in 71% (n=40; p<0.001) there was a cumulative difference of one implant size between the templated cup size and the actual cup size used. On the femoral side, in 79% (n=44; p<0.001) there was a cumulative difference of one implant size between the templated stem size and the actual stem size used. Oversizing of the implants was more prevalent, with 20% (n=11) of the acetabular components oversized by two or more sizes and 13% (n=7) of the femoral components oversized by two or more sizes. Conclusion: With the introduction of a standardised radiology programme and a stepwise templating technique, the benefits and accuracy of pre-operative templating done in a low-volume, resource-constrained orthopaedic unit is comparable to published data done in high-volume arthroplasty units. Level of evidence: Level 4

1643 A challenging diagnosis in prosthetic mitral valve obstruction

Abstract A 53-year-old man was referred to our center for a prosthesic mitral valve obstruction. In December 2017 the patient had a myocardial infarction complicated by papillary muscle rupture and anterior leaflet flail; therefore he underwent a mechanical mitral valve replacement (size 29). A first echocardiographic control in August 2018 was reported as normal. In February 2019 a further echocardiography showed an increase of the trans-prosthetic pressure gradients and a suspected restricted motion of the anterior tilting disk; a cinefluoroscopy view confirmed the tilting disk blockade in the closing position. The patient was referred to our center for further investigations. We performed a 3D TOE that confirmed the prosthesis dysfunction: the anterior tilting disk was blocked (mean gradient 14 mmHg, 3D residual anatomical area 1.4 cm2); the mechanical cause of the obstruction was not identified. A cardiac CT was performed: a clear thrombus or pannus was not visualized, even if a linear hypodensity could be seen along the inner circumferential edge of the blocked disk. Finally the patient underwent the surgical intervention for prosthesis replacement. The visual analysis of the valve revealed a stratified thrombosis in both the atrial and ventricular side of the blocked disk, extending to the prosthetic ring and to the hinges. The patient developed a prosthetic valve dysfunction 9 to 13 months after valve replacement. Thrombus is the most common cause of obstruction of mechanical prostheses (0.3 to 8% per patient-year) while pannus formation usually occur over 5 years after surgery (minimum 12 months later). On the one hand, the patient assured a good anticoagulation regimen in the previous months, thrombosis in mitral valve position usually present with a large formation involving the disk projecting into left atrium, and large prosthesis size is associated with a lower risk of thrombosis. Our TOE confirmed the hemodynamic dysfunction but was not able to detect any cause of the leafleat bloackade. Cardiac CT has a better spatial resolution but only a focused MPR view allowed to identify a linear hypodense formation along the ring surrounding the blocked disk. This thin structure only involved the prostethic ring, apparently not projecting over the disk. These morphologic features are considered more in keeping with pannus, and only the low attenuation values (below the suggested threshold of 200 HU) helped to suspect a thrombotic stratification over the prosthetic ring. The surgical intervention revealed the real nature of the obstruction. In conclusion, thrombus may present with an unconventional appearance as a cause of prosthetic obstruction and, especially when stratified can mimick a pannus. Multimodality imaging is not always able to identify the cause of mechanical valve dysfunction; consequently, when the prosthesis obstruction is evident but imaging is inconclusive cardiac surgery is the only diagnostic and therapeutic resource. Abstract 1643 Figure. Prosthesis valve disfunction

The Beneficial Effect of Anticoagulation in Aortic Bioprosthesis is Associated with its Size.

ObjectiveTo evaluate the clinical and echocardiographic outcomes in aortic valve replacement (AVR) patients with aortic bioprosthesis under oral anticoagulation (OA).MethodsPatients who underwent AVR with bioprosthesiswere prospectively enrolled. They were classified based on postoperative use of OA. Clinical and operative variables were collected. Echocardiographic and clinical follow-ups were performed two years after surgery. The primary outcome evaluated was change in transprosthetic gradient. Secondary outcomes analyzed were change in New York Heart Association (NYHA) class, major bleeding episodes, hospitalization, stroke, and transient ischemic attack.ResultsWe included 103 patients (61 without OA and 42 with OA). Clinical characteristics were similar among groups, except for younger age (76±6.3 vs. 72.4±8.1 years, P=0.016) and higher prevalence of atrial fibrillation (0% vs. 23.8%, P<0.001) in the OA group. Mean (21.4±10 mmHg vs. 16.8±7.7 mmHg, P=0.037) and maximum (33.4±13.7 mmHg vs. 28.4±10.2 mmHg, P=0.05) transprosthetic gradients were higher in patients without OA. Improvement in NYHA class was more frequent in patients with OA (73% vs. 45.3%, P=0.032). Major bleeding, stroke, and hospitalization were similar among groups. OA was the only independent predictor for improvement of NYHA class after multivariate logistic regression analysis (odds ratio [OR]: 5.9, 95% confidence interval [CI]: 1.2-29.4; P=0.028). Stratification by prosthesis size showed that patients with ≤ 21 mm prosthesis benefited from OA.ConclusionEarly anticoagulation after AVR with bioprosthesis was associated with significant decrease of transprosthesis gradient and improvement in NYHA class. These associations were seen mainly in patients with ≤ 21 mm prosthesis.

P218 Accuracy and reproducibility of aortic root assessment by eSie Valves in patients candidate to transcatheter aortic valve implantation: a comparative study with computed tomography

Abstract Background Accurate imaging assessment of the aortic root (AR) is critical for prosthesis sizing in transcatheter aortic valve implantation. Multislice computed tomography (MSCT) is the gold standard for this purpose. 3D transesophageal (3D-TOE) reconstruction tools have recently been introduced, which automatically configures a geometric model of AR from 3D-TOE dataset and perform quantitative analyses of the AR. Purpose The aim of the study was to compare semi-automated measurements of AR obtained by eSie Valves (EV) (Siemens Medical Solution, California, USA) tool with MSCT. Methods We prospectively enrolled 26 consecutive patients (mean age 79.5 ± 7.5 years; 38% men) with severe symptomatic aortic stenosis (mean gradient 48.8± 13.6 mmHg) who underwent both 3D-TOE and MSCT as part of TAVI evaluation protocol. Volumetric datasets of the AR, acquired with 3D-TOE in mid-esophageal view, were analyzed with EV tool. EV tool automatically detected AR landmarks and, after user validation, created 3D model of AR providing values of area, perimeter, diameters of aortic annulus (AA) and coronary ostia heights (Fig 1). Results EV tool analysis on 3D-TOE volumetric data sets was feasible in all patients. Strong correlation between EV tool and MSCT assessment for AA major diameter (r = 0.79), AA minor diameter (r = 0.81), AA perimeter (r = 0.89) and AA area (r = 0.89) (all p&amp;lt; 0.0001) was found. On average EV tool underestimated MSCT measurements of AA major diameter (1.2 mm, 4.5%), AA minor diameter (2.6 mm, 11.3%), AA perimeter (4 mm, 5.2%) and AA area (65.3 mmq, 13.6%). Moderate correlation between the two methods, already in this initial sample, for right coronary artery ostium height (r = 0.53, p = 0.007) was discovered. Finally, weak correlation for left coronary artery ostium height (r = 0.33, p = 0.1) was revealed. EV tool measurements from two different volumetric datasets of the same patient showed an excellent reproducibility intraclass correlation coefficient (ICC) for AA area 0.94 and ICC for right coronary height 0.98. Conclusion With these initial results EV tool could be used in clinical practice for quick and reliable assessment of AA area, perimeter and diameters. A larger group of patients will be needed to assess the consistency of coronary ostia height evaluation by EV tool. Abstract P218 Figure. eSie Valve landmarks and 3D model of AR

Animal Origin Bioactive Hydroxyapatite Thin Films Synthesized by RF-Magnetron Sputtering on 3D Printed Cranial Implants

Ti6Al4V cranial prostheses in the form of patterned meshes were 3D printed by selective laser melting in an argon environment; using a CO2 laser source and micron-sized Ti6Al4V powder as the starting material. The size and shape of prostheses were chosen based on actual computer tomography images of patient skull fractures supplied in the framework of a collaboration with a neurosurgery clinic. After optimizations of scanning speed and laser parameters, the printed material was defect-free (as shown by metallographic analyses) and chemically homogeneous, without elemental segregation or depletion. The prostheses were coated by radio-frequency magnetron sputtering (RF-MS) with a bioactive thin layer of hydroxyapatite using a bioceramic powder derived from biogenic resources (Bio-HA). Initially amorphous, the films were converted to fully-crystalline form by applying a post-deposition thermal-treatment at 500 °C/1 h in air. The X-ray diffraction structural investigations indicated the phase purity of the deposited films composed solely of a hexagonal hydroxyapatite-like compound. On the other hand, the Fourier transform infrared spectroscopic investigations revealed that the biological carbonatation of the bone mineral phase was well-replicated in the case of crystallized Bio-HA RF-MS implant coatings. The in vitro acellular assays, performed in both the fully inorganic Kokubo’s simulated body fluid and the biomimetic organic–inorganic McCoy’s 5A cell culture medium up to 21 days, emphasized both the good resistance to degradation and the biomineralization capacity of the films. Further in vitro tests conducted in SaOs-2 osteoblast-like cells showed a positive proliferation rate on the Bio-HA RF-MS coating along with a good adhesion developed on the biomaterial surface by elongated membrane protrusions.

Utility of conventional aortic root shot angiography for SAPIEN 3 prosthesis sizing in TAVI: feasibility and inter-reader variability

BackgroundThe gold-standard approach to prosthesis sizing before transcatheter aortic valve implantation (TAVI) is multislice computed tomography (MSCT). We aimed to investigate whether conventional aortic root angiography (CA) alone can reliably...

Application of preoperative digital-template planning in total hip arthroplasty via direct anterior approach

To investigate the accuracy of preoperative digital-template planning in total hip arthroplasty (THA) via direct anterior approach (DAA) and its effect on the short-term effectiveness. The clinical data of 77 patients (109 hips) with osteonecrosis of femoral head who underwent THA via DAA between January 2016 and May 2018 was retrospectively analyzed. According to the type of template, patients were divided into digital-template group (group A, 40 patients, 56 hips) and conventional-template group (group B, 37 patients, 53 hips). There was no significant difference in age, gender, body mass index, the stages of osteonecrosis of femoral head, and preoperative Harris hip score (HHS) ( P>0.05). The operation time, intraoperative blood loss, frequencies of intraoperative fluoroscopy, and complications were recorded. Otherwise, the consistency rate of preoperative planning and practical prosthesis size was analyzed. Position of acetabular prosthesis and femoral prosthesis alignment were measured on anteroposterior X-ray film of the pelvis at 3 months after operation. HHS was used to evaluate clinical function. The consistency rate of preoperative planning and practical acetabular prosthesis size was significantly higher in group A (80.4%, 45/56) than that in group B (62.3%, 33/53), showing significant difference ( χ 2=4.38, P=0.04). But there was no significant difference in the consistency rate of preoperative planning and practical femoral prosthesis size between group A (83.9%, 47/56) and group B (79.2%, 42/53）( χ 2=0.40, P=0.53). The prosthesis abductions were (40.7±6.4)° in group A and (38.8±7.3)° in group B; the femoral prosthesis alignment deviations were (0.1±1.8)° in group A and (0.3±1.7)° in group B. There was no significant difference in the prosthesis abduction and femoral prosthesis alignment deviation between 2 groups ( P>0.05). No prosthesis sinking or loosening occurred during follow-up. The operation time and frequencies of intraoperative fluoroscopy were less in group A than those in group B ( P<0.05). But there was no significant difference in intraoperative blood loss between 2 groups ( t=1.92, P=0.06). The complication occurred in 1 hip of group A and 6 hips of group B, with no significant difference ( P=0.06). All patients were followed up 6-22 months (mean 13.8 months) in group A and 6-24 months (mean, 14.6 months) in group B. At last follow-up, the HHS scores were 91.8±3.1 in group A and 92.6±4.2 in group B, and the difference was not significant ( t=1.14, P=0.26). Preoperative digital-template planning in THA via DAA is accurate, which can reduce the operation time and frequencies of intraoperative fluoroscopy without enhancing the risk of complication.

Third generation dual source CT with ultra-high pitch protocol for TAVI planning and coronary tree assessment: feasibility, image quality and diagnostic performance

PurposeTo evaluate the feasibility, image quality (IQ) and diagnostic performance of third generation 192 × 2 dual source computer tomography (DSCT) with ultra-high pitch acquisition for trans-catheter aortic valve implantation (TAVI) planning and coronary tree assessment. MethodIn this prospective study, 223 patients underwent to DSCT for TAVI. Coronary calcium scoring (CCS) was calculated. Attenuation values were measured at aortic levels, femoral and coronary arteries. IQ was evaluate with a 4-point scale. The CT performance, in the assessment of coronary stenosis ≥50 % and ≥70 %, was compared with invasive coronary angiography (ICA), served as reference standard. Aortic annulus (AoA) CT derived area and implanted prosthesis size were correlate with Spearman’s test. ResultsAttenuation values >400HU were obtain in all segments. IQ median value was ≥ 3. In the assessment of stenosis ≥50 %, on a segment-based analysis, CT sensitivity, specificity, positive and negative predictive values and diagnostic accuracy were 97.6 %, 87.6 %, 64.2 %, 99.0 % and 89.6 %, on patient-based analysis were 97.8 %, 88.8 %, 68.8 %, 99.4 % and 90.6 %, respectively. In the assessment of stenosis ≥70 %, on segment-based analysis, were 88.5 %, 83.8 %, 54.7 %, 96.8 % and 84.8 %, and on patient-based analysis were 92.5 %, 85.8 %, 58.7 %, 98.1 % and 87.0 %, respectively. The CT performed better in the group with lower CCS. A direct correlation was found between AoA CT derived area and prosthesis size. ConclusionDSCT, using a single prospective ECG-triggered ultra-high pitch acquisition, is feasible for TAVI planning and in the assessment of coronary stenosis. CT performed worse in patients with severe coronary calcifications.

Enabling Automated Device Size Selection for Transcatheter Aortic Valve Implantation.

The number of transcatheter aortic valve implantation (TAVI) procedures is expected to increase significantly in the coming years. Improving efficiency will become essential for experienced operators performing large TAVI volumes, while new operators will require training and may benefit from accurate support. In this work, we present a fast deep learning method that can predict aortic annulus perimeter and area automatically from aortic annular plane images. We propose a method combining two deep convolutional neural networks followed by a postprocessing step. The models were trained with 355 patients using modern deep learning techniques, and the method was evaluated on another 118 patients. The method was validated against an interoperator variability study of the same 118 patients. The differences between the manually obtained aortic annulus measurements and the automatic predictions were similar to the differences between two independent observers (paired diff. of 3.3 ± 16.8 mm2 vs. 1.3 ± 21.1 mm2 for the area and a paired diff. of 0.6 ± 1.7 mm vs. 0.2 ± 2.5 mm for the perimeter). The area and perimeter were used to retrieve the suggested prosthesis sizes for the Edwards Sapien 3 and the Medtronic Evolut device retrospectively. The automatically obtained device size selections accorded well with the device sizes selected by operator 1. The total analysis time from aortic annular plane to prosthesis size was below one second. This study showed that automated TAVI device size selection using the proposed method is fast, accurate, and reproducible. Comparison with the interobserver variability has shown the reliability of the strategy, and embedding this tool based on deep learning in the preoperative planning routine has the potential to increase the efficiency while ensuring accuracy.