Early Results after Aortic Valve Replacement Using Last Generation Bioprosthetic Aortic Valve

Introduction: Few data are available about the newest generation surgical bioprosthesis. We aimed to evaluate early clinical and hemodynamic outcomes after using the INSPIRIS RESILIA aortic valve (Edwards Lifesciences, Irvine, California, USA). Methods: Between July 2018 and April 2021, 80 patients underwent aortic valve replacement receiving the INSPIRIS RESILIA aortic valve at our institution. Primary outcomes were the composite of early mortality, stroke, and myocardial infarction. Secondary outcomes were hemodynamic performances of the valve, paravalvular leakage, and new pacemaker implantation. Results: The mean age of the study population was 60.6 ± 8.3 years. The mean Society of Thoracic Surgery-Predicted Risk of Mortality score was 2.9 ± 1.7%. In 43.7% of the patients, concomitant surgery was performed. The in-hospital mortality, all-stroke, and myocardial infarction rates were 2.5%, 1.2%, and 1.2%, respectively. No valve was explanted and no redo was performed. The mean postoperative trans-prosthetic gradient at discharge was 10.2 ± 4.1 mm Hg. There was no need for new pacemaker implantation. We registered only two cases with minimal (trace) paravalvular leakage. Conclusion: The use of the INSPIRIS RESILIA aortic valve in a young, low-risk population is safe and associated with very good early clinical and hemodynamic outcomes.

Quantification of noncircular stent expansion after TAVR into a pathological annulus and its impact on paravalvular leakage

Patients undergoing transcatheter aortic valve replacement (TAVR) may suffer severe clinical complications, caused by paravalvular leakage (PVL) which is defined as leakage between TAVR and aortic annulus. PVL is often facilitated by a severely calcified annulus. This limits the expansion of a self-expandable TAVR stent. To assess TAVR performance in terms of leakage, measurement of regurgitation fraction in a pathophysiological annulus is recommended according to ISO 5840. For this purpose, a configuration of a circular annulus with a calcification nodule has been proposed in the recently published ISO 5840. The impact of the proposed pathophysiological annulus model on the expansion of self-expandable TAVR stents and on the regurgitation fraction was investigated in this study. For this purpose, two commercially available selfexpandable TAVRs (Evolut R and Portico) were implanted in a calcified annulus model. Circular expansion of the TAVR stents was investigated based on μCT scans of the implanted TAVR. The calcification-induced area in which retrograde flow can occur during diastole was detected. These results were then compared with the experimentally determined regurgitation fraction obtained from pulse duplicator tests. The results of the μCT scans showed a continuous leakage area in the region of the annulus for the Evolut R compared to a locally larger leakage area of the Portico, which, however, reattaches to the annulus in the distal inflow region. The hydrodynamic measurements confirmed a smaller leakage in the pathological annulus for the Portico. In summary, it can be assumed that a continuous leakage area in the TAVR stent inflow region encourages the PVL of TAVR.

Particle Image Velocimetry for in vitro characterization of Paravalvular Leakage of TAVR-sealing concepts

Paravalvular leakage (PVL), defined as the leakage between the aortic annulus and a transcatheter aortic valve replacement (TAVR), is verifiably associated with short- and long-term clinical outcome, especially with increased mortality. Therefore, with the ambition to reduce or even prevent PVL of next generation TAVR, it is necessary to extend the hemodynamic understanding of PVL. This study presents an in vitro flow measurement method to localize PVL during hydrodynamic characterization of TAVR and furthermore presents different design features, socalled outer skirt, to reduce PVL. Particle image velocimetry (PIV) measurements were performed for flow field assessment during hydrodynamic characterization of TAVR. Additionally, two different sealing concepts were developed to reduce PVL. The skirts were manufactured from polymeric-nonwoven and sued to pericardium-based TAVR-prototype. The prepared TAVR-prototypes were then deployed in a pathophysiological model of the aortic root with a calcification nodule of 2 mm according to ISO 5840:2021. To assess PVL, the flow field and the regurgitation volume was measured. The PIV measurements showed a clearly visible leakage jet between the TAVR-prototypes without skirt and the pathophysiological aortic annulus model. Jet velocities of up to 0.5 m/s were measured depending on presence or configuration of a PVL-preventing skirt. When implanted in the physiological annulus model without calcification nodule, PVL was hardly recognizable. The regurgitation volume of a TAVR-prototype without skirt at 5 l/min was 36.26±1.89 ml (n = 10). The developed and manufactured polymeric-nonwoven skirts reduced PVL from 37.67±1.17 ml to 18.36±1.8 ml (n = 10, TAVR-skirt-design1) and from 46.97±1.07 ml to 17.85±1.29 ml (n = 10, TAVR-skirt-design2) at 5 l/min. The localization of PVL during hydrodynamic characterization by means of PIV was successful. The sealing concepts developed in this work were very effective and led to a PVL-reduction of the tested TAVR prototypes of about 50% to 70%.

Paravalvular leakage of transcatheter aortic valve replacements depending on aortic annulus calcification

Paravalvular leakage (PVL) has a crucial impact on clinical outcomes of transcateheter aortic valve replacements (TAVR), especially the mortality increases dramatically with high-grade PVL. Furthermore, the calcification of the aortic annulus has a decisive influence on the PVL of TAVR. Therefore, we developed a technical model of a calcified aortic annulus and used it for the investigation of PVL in steady-state back-flow conditions. We investigated an Evolut PRO (Medtronic, Minneapolis, MN, USA), implanted the TAVR at different depths in the aortic annulus model ranging between 0 mm and -6 mm and characterized PVL in steady-state retrograde flow from 0 mmHg up to a maximum achievable pressure. The used test bench and detailed test method was described in previous studies. The aortic annulus model exhibits three elevations symmetrically distributed around the circumference. Depending on the degree of calcification the elevations reached 1 mm to 3 mm into the lumen. For the Evolut PRO bioprosthesis, a decreasing PVL was measured with increasing implantation depth. At an implantation depth of 0 mm (inflow of TAVR and annulus model at same height) maximum PVL was measured. Minimum PVL was measured at a height of -6 mm. Furthermore, even a small calcification of 1 mm led to a large increase in PVL. This trend continued with increasing height of the calcification. The maximum regurgitation of (2,025.21 ± 12.47) ml (n = 3 measurements) was measured at a pressure of 6 mmHg in the annulus model with 3 mm calcification. A test method to quantify PVL depending on annular calcification was successfully developed. Additionally, the influence of implantation depth on PVL was characterized. Due to the technical operating principle of the test bench, only a limited increase in pressure was possible when large PVL occurred. In this respect, the test bench must be optimized in the future.

Contemporary short-term outcomes of surgery for aortic stenosis: transcatheter vs. surgical aortic valve replacement

Objectives This study aimed to compare the short-term outcomes of transcatheter and surgical aortic valve replacements (TAVR and SAVR) in high-, intermediate-, and low-preoperative risk patients. Methods A total of 454 patients who underwent TAVR or SAVR were included. Patients were categorized into high-, intermediate-, and low-risk according to the Society of Thoracic Surgery-Predicted Risk of Mortality score and clinical outcomes were compared between TAVR and SAVR groups. Results TAVR was less invasive, with less bleeding and transfusion (p < 0.001), less frequent new-onset atrial fibrillation (p < 0.001), and shorter intensive care unit stay (p < 0.001). Furthermore, transcatheter valves performed better than surgical valves, with lower peak velocity (p = 0.003) and pressure gradient (p < 0.001) and higher effective orifice area index (p < 0.001). The clinical outcomes of TAVR were comparable to or even superior to those of SAVR in high- and intermediate-risk patients. In low-risk patients, the 1- and 2-year mortality rates were 6.3% and 12.1%, respectively, in the TAVR group and 0% and 0.9%, respectively, in the SAVR group (p < 0.001). Mild or greater paravalvular leakage was a risk factor for mortality (hazard ratio 35.78; p < 0.001). Conclusions TAVR was superior to SAVR in the sense of less invasiveness and valvular function. However, the indication of TAVR in low-risk patients should be carefully discussed, because paravalvular leakage was a risk factor for short-term mortality.

AB0363 PERIOPERATIVE MANAGEMENT WITH BIOLOGICS ON SEVERE AORTIC VALVE REGURGITATION CAUSED BY BEHÇET’S SYNDROME: THE EXPERIENCE FROM A SINGLE CENTER

Background:Cardiovascular involvement in Behçet’s syndrome (BS) is associated with poor prognosis and accounts for the leading cause of mortality and morbidity in BS1, 2. Perioperative management of severe aortic valve regurgitation (AR) caused by BS is critical while challenging. AR caused by BS is associated with a high incidence of severe postoperative complications, especially paravalvular leakage (PVL) due to the fragilities of aortic lesions and tissue inflammation, leading to a significantly increased risk of re-operation and life-threatening conditions3-5. For the perioperative management of patients with AR caused by BS, many patients respond inadequately to the combination therapies of glucocorticoids (GCs) and immunosuppressants. Meanwhile, rapid and efficient control of inflammation is critical in preserving cardiac function and surgical management. However, the application of biologics in the perioperative treatment of AR attributable to BS has not yet been evaluated.Objectives:To investigate the efficacy and safety of biologics in the perioperative management of severe AR caused by BS.Methods:We retrospectively analyzed twenty patients with severe AR caused by BS and were treated with biologics during the perioperative cardiac surgeries in our center between February 2016 and October 2020.Results:Twenty patients with severe AR were enrolled, including 19 males and 1 female, with a mean age of 39.1±8.8 years and median course 8 (IQR, 5.25-10) years. Before biologics administration, 92.9% of the patients who underwent aortic valve replacement surgeries had failed conventional therapy and developed postoperative paravalvular leakage (PVL) at a median interval of 4 months. Biologics was administered during the perioperative period of 22 aortic valve surgeries, including preoperatively with a median interval of 3.5 (IQR, 2.75-4.25) months in 13 cases, or within three-month postoperatively in 9 cases, with background glucocorticoids (GCs) and immunosuppressants. After a median follow-up of 21 (IQR, 15-32) months, 11 out of 13 cases (84.6%) preoperatively and 8 out of 9 cases (88.9%) postoperatively treated with biologics were event-free. The BDCAF score improved significantly (7 vs. 0, median, p<0.0001). Significant decrease of ESR (25.0 (IQR, 11-36.25) mm/h vs. 6.5 (IQR, 4-8.8) mm/h, p<0.001), and CRP (20.77 (IQR, 7.19-29.58) mg/L vs. 1.53 (IQR, 0.94-2.92) mg/L, p=0.001) were achieved rapidly and effectively. The dosage of GCs tapered from 40 (IQR, 30-60) mg/d to 10 (IQR, 5-11.25) mg/d, p<0.0001. Immunosuppressants were tapered in number and dosage in 6 (30%) and 20 patients (100%), respectively. No serious adverse event was observed.Conclusion:Our study suggests that biologics was effective and well-tolerated for the perioperative management of severe and refractory AR caused by BS, which significantly reduced the occurrence of postoperative PVL and had a favorable GCs- and immunosuppressants- sparing effect.References:[1]Saadoun D, Wechsler B, Desseaux K, et al. Mortality in Behcet’s disease. Arthritis Rheum 2010; 62: 2806-2812.[2]Thomas T, Chandan JS, Subramanian A, et al. Epidemiology, morbidity and mortality in Behcet’s disease: a cohort study using The Health Improvement Network (THIN). Rheumatology (Oxford) 2020; 59: 2785-2795.[3]Ando M, Kosakai Y, Okita Y, et al. Surgical treatment of Behcet’s disease involving aortic regurgitation. Ann Thorac Surg 1999; 68: 2136-2140.[4]Han JK, Kim HK, Kim YJ, et al. Behcet’s disease as a frequently unrecognized cause of aortic regurgitation: suggestive and misleading echocardiography findings. J Am Soc Echocardiogr 2009; 22: 1269-1274.[5]Guo X, Tian Z, Liu Y, et al. Preoperative immunosuppressive therapy reduces paravalvular leakage after aortic valve surgery in patients with aortic regurgitation attributable to Behcet’s disease. Clin Exp Rheumatol 2016; 34: S26-S33.Disclosure of Interests:None declared

Implantation depth and its influence on complications after TAVI with self-expanding valves

Prior studies in patients with transcatheter aortic valve implantation (TAVI) demonstrated an influence of transcatheter heart valve (THV) position on the occurrence of new conductions disturbances (CD) and paravalvular leakage (PVL) post TAVI in balloon-expandable valves (BEV). Purpose of this study was to investigate the THV implantation depth and its influence on the occurrence of CD and PVL in self-expanding valves (SEV). We performed fusion imaging of pre- and post-procedural computed tomography angiography in 104 TAVI-patients (all with Evolut R) to receive a 3-D reconstruction of the THV within the native annulus region. The THV length below the native annulus was measured for assessment of implantation depth. Electrocardiograms pre-discharge were assessed for conduction disturbances (CD), PVL was determined in transthoracic echocardiography. The mean implantation depth of the THV in the whole cohort was 4.3 ± 3.0 mm. Using the best cut-off of ≥ 4 mm in receiver operating characteristic curve analysis (sensitivity 83.3%, specificity 60.0%) patients with lower THV position developed more new CD after TAVI (68.2 vs. 23.7%, P < 0.001). A deep THV position was identified as the only predictor for new CD after TAVI (odds ratio [CI] 1.312[1.119–1.539], P = 0.001). The implantation depth showed no influence on the grade of PVL (r = 0.052, P = 0.598). In patients with TAVI using the Evolut R SEV, a lower THV positioning (≥ 4 mm length below annulus) was a predictor for new conduction disturbances. In contrast, implantation depth was not associated with the extent of PVL. Graphic abstract Prostheses positions of self-expanding valves and their influence on the occurrence of new conduction disturbances and the grade of paravalvular leakage after TAVI.

Determinants of paravalvular leakage following transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis

Aims Paravalvular leakage (PVL) after transcatheter aortic valve replacement (TAVR) is a common complication in patients with bicuspid aortic valve (BAV). However, predictors and mechanisms of PVL are not well understood in this subset. The aim of this study was to analyse determinants and mechanisms of PVL in BAV and tricuspid aortic valve (TAV). Methods and results Of the 2394 consecutive patients undergoing transfemoral TAVR using new-generation valves at our centre, we identified 242 cases with BAV. To adjust for baseline differences, we performed 3 : 1 propensity score matching (TAVPS n = 726). We analysed the aortic root anatomy and calcification as well as the number, circumferential distribution, and predilection sites of PVL using pre-procedural multidetector computed tomography and post-TAVR echocardiography. In the matched cohort, the incidence of PVL ≥mild (BAV 51.9% vs. TAVPS 51.7%; P = 0.955) and PVL ≥moderate (BAV 5.0% vs. TAVPS 3.7%; P = 0.393), the circumferential distribution, and independent predictors were similar between BAV and TAVPS. Both the presence of peri-annular calcium chunks or LVOT calcification were highly associated with PVL in BAV and TAVPS patients, whereas in BAV patients neither the presence of a calcium bridge nor the volume of its calcification was related to PVL. Notably, the spatial localization of these lesions did not necessarily match the circumferential leak position. Conclusion The incidence, circumferential distribution, predilection sites, and predictors of PVL were similar in matched population of BAV and TAVPS patients undergoing transfemoral TAVR using new-generation devices. These novel findings suggest a common underlying mechanism of PVL in both entities.