Andreas Holzamer

Background: The primary objective of this study was to evaluate the initial experience in Germany with the Meril Myval™ (MM) transcatheter heart valve (THV) system for the treatment of severe symptomatic aortic valve stenosis. The MM THV is a novel balloon-expandable valve with an expanded sizing matrix. Contemporary patients undergoing TAVI with the established Edwards Sapien™ (ES) THV served as the comparator group. Methods: Between 1st March and 31 August 2020 a total of 134 patients (33% female, 80.1 ± 6.7 years; EuroScore II 4.7 ± 4.8) underwent TAVI with an MM (95% transfemoral) for severe aortic stenosis at six German tertiary care centers. Results: Correct positioning of the THV was achieved in 98.5% (n = 132). Mean aortic gradients (MPG) were reduced from 42 ± 14 mmHg to 11 ± 5 mmHg. Mild postprocedural paravalvular leak (PVL) was observed in 62% (n = 82) patients, whereas only one patient had more than mild PVL. New permanent pacemaker implantation (PPI) was indicated in 15 patients (11%). Major vascular complications occurred in 6.7% (n = 9) patients. The in-hospital combined incidence of all-cause death and stroke was 4.5% (n = 6). In the comparator group that included 268 patients, the 30-day incidences of PPI, major vascular complications, and the composite of all-cause death and stroke were 16%, 1.9%, and 7.1%, respectively; MPGs were reduced from 44 ± 15 mmHg to 12.8 ± 4.6 mmHg and the more than mild PVL occurred in 0.7%. Conclusions: The MM is a promising novel THV system, with performance comparable to the established ES THVs. These findings await confirmation by ongoing randomized trials.

Background: Extremely large aortic valve anatomy is one of the remaining limitations leading to exclusion of patients for transcatheter aortic valve replacement (TAVR).Aims: The newly approved Myval 32 mm device is designed for use in aortic annulus areas up to 840 mm². Here we want to share the initial worldwide experience with the device.Methods and Results: Retrospective data were collected from 10 patients with aortic stenosis and very large annular anatomy (mean area 765.5 mm²), who underwent implantation with 32 mm Myval transcatheter heart valve at eight centers. Valve Academic Research Consortium‐2 device success was achieved in all cases. Mild paravalvular leak was observed in three patients and two patients required new pacemaker implantation. One patient experienced retroperitoneal hemorrhage caused by the contralateral 6 F sheath and required surgical revision. No device‐related complications, stroke, or death from any cause occurred within the 30‐day follow‐up period. In a studied cohort of 2219 consecutive TAVR‐screened patients from a central European site, only 0.27% of patients showed larger anatomy than covered by the 32 mm Myval device by instructions for use without off‐label use of overexpansion. This rate was significantly higher for the 34 mm Evolut Pro (1.8%) and 29 mm Sapien 3 (2.1%) devices.Conclusions: The Myval 32 mm prosthesis showed promising initial results in a cohort of patients who previously had to be excluded from TAVR. It is desirable that all future TAVR systems accommodate larger anatomy to allow optimal treatment of all patients.

Registry of 113 patients undergoing TAVI for pure AR demonstrates 97.3% success rate with high valve oversizing and introduces LVOT shape classification system to predict embolization risk.

Background: Patients with depressed left ventricular ejection fraction (dLVEF) constitute a particularly high-risk subset in TAVI. Use of prophylactic veno-arterial extracorporeal membrane oxygenation (pECMO) has been previously described in patients with high operative risk to guarantee full hemodynamic capability and support during TAVI.

Objectives: Treatment of bicuspid aortic valve stenosis (BAV) by transcatheter aortic valve implantation (TAVI) is increasingly performed and shows promising results. Nevertheless, TAVI in BAV is generally considered as more challenging than in regular tricuspid anatomy. One of the underlying reasons can be the difficulty to determine suitable fluoroscopic implantation planes, especially as the regular TAVI approach based on the three cusps' nadirs is not feasible in BAV by definition. We present a method to predict implantation planes by assessment of the preoperative CT scan, and describe its impact on our center's implantations. Methods: In our approach, the positioning of the TAVI prosthesis in the patient's anatomy is approximated by a vector in the preoperative CT scan. This vector is constructed by the centroid of a polygon that outlines the aorta in the region of the sinotubular junction and, respectively, of the subvalvular LVOT. The 3D coordinates of the two centroids are used to calculate the line of perpendicularity that represents all orthogonal perspectives to the aortic valve's annulus. Verification of the vector can be undertaken by systematic analysis of the resulting orthogonal sectional plane's area that defines the aortic annulus. 58 patients with stenotic BAV (Sievers 0 and I) that were suitable to analyze the method's efficacy underwent TAVI in our institution. Two subgroups were formed according to the technique used for the implantation plane prediction. In group A (n = 26), the plane was determined by experienced operators using different CT-based presumptions and fluoroscopic methods like angiograms or alignment of the crimped valve. In group B, the new approach was used to predict the final implantation plane. After implantation, the solid angle that represents the tilt of the implanted prostheses to the predicted projection was calculated using fluoroscopy. Homoscedasticity of the measurements was confirmed by Levine-test, and Student's t-test was used to determine significance of differences between the means. Results: The mean solid angle between the fluoroscopic implantation plane and the prosthesis was significantly lower in group B (5.2°, SD = 2.9° versus group A: 11.0°, SD = 5.3°; p < 0.01). Conclusion: The new method led to a significant reduction of the misalignment between the chosen fluoroscopic projection and the final position of the prosthesis. This might allow more precise valve deployment and improve the procedural outcomes.

Objectives: Extracorporeal life support systems (ECLS) are designed for whole body perfusion. We report on a case with selective perfusion of an amputated leg to enable autologous tissue donation for reconstructive surgery. Methods: A 23-year-old patient suffered complete amputation of the right leg at the level of the pelvic ring along with multiple bone fractures, intestinal prolapse, and burn injuries during a car accident. After hemodynamic stabilization it was decided to selectively perfuse the amputated right leg with an ECLS system to maintain viability of the tissue, which can then later be used for reconstructive surgery for the pelvic ring. The femoral artery and vein were cannulated (14/18 Fr) and limb perfusion established with 1 L/min for 12 hours under massive volume substitution. Thereafter, the pelvic ring was reconstructed utilizing tissue from the amputated leg. Results: After 5 months, the patient could be discharged to a rehabilitation center, and a prosthetic leg was customized. Meanwhile, the patient is back to work. Conclusion: Selective perfusion of amputated body parts with ECLS can be performed for maintain tissue viability for later reconstructive surgery. ECMO centers should be aware of this possibility.

Objectives: TAVI is an alternative treatment option for high-risk patients with aortic valve disease who are ineligible for conventional surgical valve replacement. Almost all patients undergo both multi slice computed tomography scan (CT) and coronary angiogram (CA) prior to TAVI. Postoperative renal failure is a known significant risk factor for prolonged hospital stay and is associated with a two- to sixfold higher mortality in the TAVI collective. Aim of our study was to examine whether the timespan between the last preoperative application of contrast agent (CT or CA) and the procedure influences renal failure defined by VARC-2 criteria. Results may influence the preoperative strategy regarding the timing of the diagnostics. Methods: A total of 656 consecutive patients were screened from December 2013 to August 2016. Exclusion criteria were chronic dialysis and critical preoperative state as defined by the EuroScore study group. Based on these criteria, 603 patients were included in the study. According to the last diagnostic contrast application, one group with near-term contrast exposure (NT, 1–3 days) and one group with long-term contrast exposure (LT, ≥4 days) prior to TAVI were formed. Postoperative renal failure was defined using the AKIN 2 criteria according to VARC-2 (increase of GRF >200% of baseline value or renal replacement therapy). Bias by comorbidities and impact of renal outcome by different amounts of intraoperatively used contrast agent could be excluded. Statistical analysis was performed using Student t-test and Pearson chi-square test. SPSS version 23 was used for statistical calculations. Results: There was no significant difference in GFR impairment (NT: −9.8 ± 17.5 mL/min vs. LT: −7.9 ± 15.6 mL/min; p = 0.21), VARC-2 relevant acute kidney injury (NT: n = 18 (9.9%) vs. LT: n = 27 (6.4%); p = 0.13), need for postoperative renal replacement therapy (NT: n = 9 (5.0%) vs. LT n = 13 (3.1%); p = 0.26) or 30-day mortality (NT: n = 9 (5.2%) vs. LT: n = 15 (3.8%); p = 0.43). Conclusion: The timing of the last diagnostic examination that requires contrast agent prior to TAVI did not show significant impact in our study. Therefore, a fast track approach to minimize preoperative hospital stay seems to be secure in general. However, especially in patients with preoperatively impaired renal function, further data about the best strategy is missing.

Objectives: Preoperative CT-based sizing has proven to be crucial for safe TAVI procedures and is performed in almost all cases nowadays. Nevertheless, many implanting physicians are not able to perform the sizing as dedicated TAVI software is not available in their center. The OsiriX software is one of the most spread open source DICOM viewers and frequently used for TAVI sizing. We developed a free available OsiriX software plugin that guides the user through the sizing process, automates routine steps and creates interactive reports including the valve sizing and suggestion of suitable implantation planes. In this study, we want so present the data of the clinical software validation process. Methods: CT scans of 50 concomitant patients who underwent TAVI were anonymized and randomly sorted. Two experienced observers from different German TAVI centers examined all scans with both the new Osirix plugin (OP) and the commercial 3Mensio Structural Heart software (3M). Measurements included annulus perimeter, area, min/max diameters, coronary distance and implantation plane. Inter- and intraobserver variability were compared using Bland-Altman plots for determination of accuracy, and a linear regression model for detection of constant and proportional bias (Passing-Bablok, CUSUM linearity test). Results: Interobserver analysis shows the reproducibility of measurements by different observers for both applications. Intraobserver analysis shows the impact of different software on the measurements for the same observers. Conclusion: Both applications showed basically equal performance. No clinically relevant difference of limits of agreement could be detected. Furthermore, constant and proportional bias caused by the choice of software or observer could also be rejected for all examined measurements. The Limits of agreement of annulus measurements are within clinical needs. The variability of measurements of coronary distances in both applications makes further considerations like width of the sinus important for safe implantations.

Objectives: In some patients who undergo transcatheter aortic valve implantation (TAVI), the aortic annulus is more vertically or horizontally orientated than in standard cases. We demonstrate a method to calculate the solid angle between the patient's longitudinal axis and the aortic annulus plane that represents this anatomical aspect. Furthermore, we investigated its impact on residual aortic regurgitation after TAVI. Methods: For TAVI purposes, the aortic annulus plane is defined by the three lowest points of the valve's cusps (“hinge points”). In 588 patients, we measured the coordinates of the hinge points by 3D CT analysis prior to TAVI. The solid angle between the annulus plane given by the coordinates and the patient's longitudinal axis was calculated using vector mathematics. Post-procedural aortic valve regurgitation (AR) was examined by TEE and fluoroscopy in all cases. For TA versus TF approach and each type of prostheses with at least 50 performed implantations in the cohort, the correlation between AR and the solid angle was examined using Spearman's correlation. Results: The mean solid angle was 49,5° ( ± 8,7°). Extreme values were 79,7° and 27,9°, respectively. There was no significant correlation between the angle and patient's gender or preoperative LVEF. In the TF collective (n = 358), significant positive correlation between AR and the solid angle was given (p = .025). The examined TF valves (Corevalve [n = 63], Sapien 3/XT [n = 140/87], Symetis neo [n = 65]) showed positive correlation coefficients, but only in the Corevalve cohort significance of the correlation (p< 0.001) was observed. The TA cohort (n = 230) showed negative but non-significant correlation. This finding was equal in both relevant subgroups (Symetis TA [n = 151], Medtronic Engager [n = 53]). Conclusion: The strongly varying angle between the patient's longitudinal axis and the aortic annulus plane should be considered in TAVI planning. It might influence the choice of type of prostheses as well as delivery approach. The presented method allows a standardized and fast quantification of this angle.