Twenty-year experience following aortic valve replacement in patients younger than 60 years of age.

OBJECTIVE: Reports on long-term outcomes of surgical aortic valve replacement (AVR) for patients aged < 60 years are scarce in Japan. Hence, we aimed to evaluate these outcomes in patients aged < 60 years. METHODS: Between March 2000 and December 2020, 1477 patients underwent aortic valve replacement. In total, 170 patients aged < 60 years who underwent aortic valve replacement were recruited. Patients aged < 18 years were excluded. Patient data collected from the operative records and follow-up assessments were reviewed. RESULTS: The mean age was 49 ± 9 years, and 64.1% of patients were male. One-hundred-and-fifty-two patients (89.4%) underwent aortic valve replacement with a mechanical valve and 18 (10.6%) with a bioprosthetic valve. The mean follow-up period was 8.1 ± 5.5 years. No operative mortality occurred, and in-hospital mortality occurred in one patient (0.6%). Ten late deaths occurred, with seven cardiac-related deaths. The overall survival rate was 95.4 ± 1.7%, 93.9 ± 2.3%, 90.6 ± 3.9%, and 73.2 ± 11.8% at 5, 10, 15, and 20 years, respectively. Freedom from major bleeding was 96.4 ± 1.6% at 5, 10, and 15 years, and 89.0 ± 7.3% at 20 years. Freedom from thromboembolic events was 98.7 ± 1.3%, 97.3 ± 1.9%, 90.5 ± 4.5%, and 79.0 ± 11.3% at 5, 10, 15, and 20 years, respectively. Freedom from valve-related reoperation was 99.4 ± 0.6% at 5 years, 97.8 ± 1.7% at 10 and 15 years, and 63.9 ± 14.5% at 20 years. CONCLUSIONS: Patients aged < 60 years undergoing aortic valve replacement with a high mechanical valve implantation rate had favorable long-term outcomes.

Anomalous circumflex artery encircling the aortic annulus: implications for mitral valve repair.

Injury to coronary arteries during mitral surgery is a rare but life-threatening procedural complication, an anomalous origin and course of the left circumflex artery (LCx) increase this risk. Recognizing the anomaly by the characteristic angiographic pattern and identifying its relationship with the surrounding anatomical structure using imaging techniques, mainly transesophageal echocardiography (TOE) or coronary computed tomography angiography (CCTA), is of crucial importance in setting up the best surgical strategy. We report a case of anomalous origin of a circumflex artery (LCx) from the proximal portion of the right coronary artery (RCA) with a pathway running retroaortically through the mitro-aortic space. An integrated diagnostic approach using a multidisciplinary team with a cardiologist and an imaging radiologist allowed us to decide the surgical strategy. We successfully performed a mitral valvular repair using a minimally invasive minithoracotomic approach and implanting a complete semirigid ring.

Quadricuspid Aortic Valve: Interesting Images.

ABSTRACT: The quadricuspid aortic valve is a rare congenital anomaly, usually associated with aortic regurgitation requiring surgical intervention. It may be associated with other congenital anomalies such as coronary anomalies, patent ductus arteriosus, ventricular septal defect, pulmonary stenosis, and subaortic stenosis. The diagnosis is generally established by either transthoracic or transesophageal echocardiography. Herein, we report a case of a 52-year-old woman who was diagnosed to have quadricuspid aortic valve by intraoperative transesophageal echocardiography.

Examining the typical hemodynamic performance of nearly 3000 modern surgical aortic bioprostheses.

OBJECTIVES: The objective of this analysis was to assess the normal haemodynamic performance of contemporary surgical aortic valves at 1 year postimplant in patients undergoing surgical aortic valve replacement for significant valvular dysfunction. By pooling data from 4 multicentre studies, this study will contribute to a better understanding of the effectiveness of surgical aortic valve replacement procedures, aiding clinicians and researchers in making informed decisions regarding valve selection and patient management. METHODS: Echocardiograms were assessed by a single core laboratory. Effective orifice area, dimensionless velocity index, mean aortic gradient, peak aortic velocity and stroke volume were evaluated. RESULTS: The cohort included 2958 patients. Baseline age in the studies ranged from 70.1 ± 9.0 to 83.3 ± 6.4 years, and Society of Thoracic Surgeons risk of mortality was 1.9 ± 0.7 to 7.5 ± 3.4%. Twenty patients who had received a valve model implanted in fewer than 10 cases were excluded. Ten valve models (all tissue valves; n = 2938 patients) were analysed. At 1 year, population mean effective orifice area ranged from 1.46 ± 0.34 to 2.12 ± 0.59 cm2, and dimensionless velocity index, from 0.39 ± 0.07 to 0.56 ± 0.15. The mean gradient ranged from 8.6 ± 3.4 to 16.1 ± 6.2 mmHg with peak aortic velocity of 1.96 ± 0.39 to 2.65 ± 0.47 m/s. Stroke volume was 75.3 ± 19.6 to 89.8 ± 24.3 ml. CONCLUSIONS: This pooled cohort is the largest to date of contemporary surgical aortic valves with echocardiograms analysed by a single core lab. Overall haemodynamic performance at 1 year ranged from good to excellent. These data can serve as a benchmark for other studies and may be useful to evaluate the performance of bioprosthetic surgical valves over time. CLINICAL TRIAL REGISTRATION NUMBER: NCT02088554, NCT02701283, NCT01586910 and NCT01531374.

Intraoperative Transesophageal Echocardiographic Assessment of Aortic Valve Repair in a Child - What to Look for?

ABSTRACT: Aortic valve (AV) repair is the desired surgical treatment option for young patients with aortic regurgitation (AR). It is considered as a class I indication for the surgical treatment of severeAR. The success of an AV repair depends on the detailed intraoperative transesophageal echocardiographic (TEE) examination which should fulfil the information required by the surgeon. The objective of this echo round is to describe the role of intraoperative TEE in systematic evaluation of the AV, before and after repair.

Performance and outcomes of the SAPIEN 3 Ultra RESILIA transcatheter heart valve in the OCEAN-TAVI registry.

BACKGROUND: Data on the performance of the latest-generation SAPIEN 3 Ultra RESILIA (S3UR) valve in patients who undergo transcatheter aortic valve replacement (TAVR) are scarce. AIMS: We aimed to assess the clinical outcomes, including valve performance, of the S3UR. METHODS: Registry data of 618 consecutive patients with S3UR and of a historical pooled cohort of 8,750 patients who had a SAPIEN 3 (S3) valve and underwent TAVR were collected. The clinical outcomes and haemodynamics, including patient-prosthesis mismatch (PPM), were compared between the 2 groups and in a propensity-matched cohort. RESULTS: The incidence of in-hospital death, vascular complications, and new pacemaker implantation was similar between the S3UR and the S3 groups (allp>0.05). However, both groups showed significant differences in the degrees of paravalvular leakage (PVL) (none-trivial: 87.0% vs 78.5%, mild: 12.5% vs 20.5%, ≥moderate: 0.5% vs 1.1%; p<0.001) and the incidence of PPM (none: 94.3% vs 85.1%, moderate: 5.2% vs 12.8%, severe: 0.5% vs 2.0%; p<0.001). The prevalence of a mean pressure gradient ≥20 mmHg was significantly lower in the S3UR group (1.6% vs 6.2%; p<0.001). Better haemodynamics were observed with the smaller 20 mm and 23 mm S3UR valves. The results were consistent in a matched cohort of patients with S3UR and with S3 (n=618 patients/group). CONCLUSIONS: The S3UR has equivalent procedural complications to the S3 but with lower rates of PVL and significantly better valve performance. The better valve performance of the S3UR, particularly in smaller valve sizes, overcomes the remaining issue of balloon-expandable valves after TAVR.

Defining high bleeding risk in patients undergoing transcatheter aortic valve implantation: a VARC-HBR consensus document.

The identification and management of patients at high bleeding risk (HBR) undergoing transcatheter aortic valve implantation (TAVI) are of major importance, but the lack of standardised definitions is challenging for trial design, data interpretation, and clinical decision-making. The Valve Academic Research Consortium for High Bleeding Risk (VARC-HBR) is a collaboration among leading research organisations, regulatory authorities, and physician-scientists from Europe, the USA, and Asia, with a major focus on TAVI-related bleeding. VARC-HBR is an initiative of the CERC (Cardiovascular European Research Center), aiming to develop a consensus definition of TAVI patients at HBR, based on a systematic review of the available evidence, to provide consistency for future clinical trials, clinical decision-making, and regulatory review. This document represents the first pragmatic approach to a consistent definition of HBR evaluating the safety and effectiveness of procedures, devices and drug regimens for patients undergoing TAVI..

Role of aortic valve replacement in moderate aortic stenosis: a 10-year outcomes study.

OBJECTIVE: Patients with moderate aortic stenosis (AS) exhibit high morbidity and mortality. Limited evidence exists on the role of aortic valve replacement (AVR) in this patient population. To investigate the benefit of AVR in moderate AS on survival and left ventricular function. METHODS: In a retrospective cohort study, patients with moderate AS between 2008 and 2016 were selected from the Cleveland Clinic echocardiography database and followed until 2018. Patients were classified as receiving AVR or managed medically (clinical surveillance). All-cause and cardiovascular mortality were assessed by survival analyses. Temporal haemodynamic and structural changes were assessed with longitudinal analyses using linear mixed effects models. RESULTS: We included 1421 patients (mean age, 75.3±5.4 years and 39.9% women) followed over a median duration of 6 years. Patients in the AVR group had lower risk of all-cause (adjusted HR (aHR)=0.51, 95% CI: 0.34 to 0.77; p=0.001) and cardiovascular mortality (aHR=0.50, 95% CI: 0.31 to 0.80; p=0.004) compared with those in the clinical surveillance group irrespective of sex, receipt of other open-heart surgeries and underlying malignancy. These findings were seen only in those with preserved left ventricular ejection fraction (LVEF) ≥50%. Further, patients in the AVR group had a significant trend towards an increase in LVEF and a decrease in right ventricular systolic pressure compared with those in the clinical surveillance group. CONCLUSIONS: In patients with moderate AS, AVR was associated with favourable clinical outcomes and left ventricular remodelling.

Hyperglycemia-simulating environment attenuated experimentally induced calcification in cultured human aortic valve interstitial cells.

Objectives: The role of diabetes mellitus as a risk factor for the development of calcific aortic valve disease has not been fully clarified. Aortic valve interstitial cells (VICs) have been suggested to be crucial for calcification of the valve. Induced calcification in cultured VICs is a good in vitro model for aortic valve calcification. The purpose of this study was to investigate whether increased glucose levels increase experimentally induced calcification in cultured human VICs. Design: VICs were isolated from explanted calcified aortic valves after valve replacement. Osteogenic medium induced calcification of cultured VICs at different glucose levels (5, 15, and 25 mM). Calcium deposits were visualized using Alizarin Red staining and measured spectrophotometrically. Results: The higher the glucose concentration, the lower the level of calcification. High glucose (25 mM) reduced calcification by 52% compared with calcification at a physiological (5 mM) glucose concentration (correlation and regression analysis: r = -0.55, p = .025 with increased concentration of glucose). Conclusions: In vitro hyperglycemia-like conditions attenuated calcification in VICs. High glucose levels may trigger a series of events that secondarily stimulate calcification of VICs in vivo.

First-time surgical aortic valve replacement: nationwide trends and outcomes from The Netherlands Heart Registration.

OBJECTIVES: The aim of this study was to describe trends and outcomes for patients undergoing surgical aortic valve replacement (SAVR) in the Netherlands. METHODS: The Netherlands Heart Registration database was used to report the number and outcomes of isolated, primary SAVR procedures performed from 2007 to 2018 in adult patients. RESULTS: A total of 17 142 procedures were included, of which 77.9% were performed using a biological prosthesis and 21.0% with a mechanical prosthesis. Median logistic EuroSCORE I decreased from 4.6 [interquartile range (IQR) 2.4-7.7] to 4.0 (IQR 2.6-6.0). The 120-day mortality decreased from 3.3% in 2007 to 0.7% in 2018. The median duration of follow-up was 76 months (IQR 53-111). Ten-year survival, when adjusted for age, EuroSCORE I and body surface area, was 72.4%, and adjusted 10-year freedom from reinvervention was 98.1%. Additional analysis for patients under the age of 60 showed no difference between patients treated with a biological or mechanical prosthesis in adjusted 10-year survival, 89.7% vs 91.9±%, respectively (P = 0.25), but a significant difference in adjusted 10-year freedom from reintervention, 90.0±% vs 95.9%, respectively (P < 0.01). CONCLUSIONS: Between 2007 and 2018, age and risk profile of patients undergoing SAVR decreased, especially for patients treated with a biological prosthesis. The 120-day mortality decreased over time. Patients undergoing SAVR nowadays have a risk of 120-day mortality of <1% and 10-year freedom from valve-related reintervention of >95%.

Surgical Technique And Clinical Implications Of Transcatheter Aortic Valve Bioprosthesis Explantation.

There has been a worldwide rapid adoption of transcatheter aortic valve replacement (TAVR) as an alternative to surgical aortic valve replacement (SAVR) for patients with severe aortic stenosis. Currently, more TAVR explants with SAVRs are performed than TAVR-in TAV. TAVR explantation is a technically hazardous procedure mainly due to significant aortic neo-endothelialization which incorporates the TAVR valve. Surgical techniques for TAVR explantation are not well established and surgeon experience at present is limited. In this manuscript, we describe our technique for surgical explantation of transcatheter aortic bioprosthesis. Familiarity with the procedure and its clinical implications is essential for all cardiac surgeons.

Epicardial fat volume is associated with primary coronary slow-flow phenomenon in patients with severe aortic stenosis undergoing transcatheter valve implantation.

BACKGROUND: Primary coronary slow flow (CSF) is defined as delayed opacification of the distal epicardial vasculature during coronary angiography in the absence of relevant coronary artery stenoses. Microvascular disease is thought to be the underlying cause of this pathology. Epicardial fat tissue (EFT) is an active endocrine organ directly surrounding the coronary arteries that provides pro-inflammatory factors to the adjacent tissue by paracrine and vasocrine mechanisms. The aim of the present study was to investigate a potential association between EFT and primary CSF and whether EFT can predict the presence of primary CSF. METHODS: Between 2016 and 2017, n = 88 patients with high-grade aortic stenosis who were planned for transcatheter aortic valve implantation (TAVI) were included in this retrospective study. EFT volume was measured by pre-TAVI computed tomography (CT) using dedicated software. The presence of primary CSF was defined based on the TIMI frame count from the pre-TAVI coronary angiograms. RESULTS: Thirty-nine of 88 TAVI patients had CSF (44.3%). EFT volume was markedly higher in patients with CSF (142 ml [IQR 107-180] vs. 113 ml [IQR 89-147]; p = 0.009) and was strongly associated with the presence of CSF (OR 1.012 [95%CI 1.002-1.021]; p = 0.014). After adjustment, EFT volume was still an independent predictor of CSF (OR 1.016 [95%CI 1.004-1.026]; p = 0.009). CONCLUSION: Primary CSF was independently associated with increased EFT volume. Further studies are needed to validate this finding and elucidate whether a causal relationship exists.

Interventricular septal thickness on cardiac computed tomography as a novel risk factor for conduction disturbances in patients undergoing transcatheter aortic valve replacement.

AIMS: We examined whether thickness of the basal muscular interventricular septum (IVS), as measured by pre-procedural computed tomography (CT), could be used to identify the risk of conduction disturbances following transcatheter aortic valve replacement (TAVR). The IVS is a pivotal region of the electrical conduction system of the heart where the atrioventricular conduction axis is located. METHODS AND RESULTS: Included were 78 patients with severe aortic stenosis who underwent CT imaging prior to TAVR. The thickness of muscular IVS was measured in the coronal view, in systolic phases, at 1, 2, 5, and 10 mm below the membranous septum (MS). The primary endpoint was a composite of conduction disturbance following TAVR. Conduction disturbances occurred in 24 out of 78 patients (30.8%). Those with conduction disturbances were significantly more likely to have a thinner IVS than those without conduction disturbances at every measured IVS level (2.98 ± 0.52 mm vs. 3.38 ± 0.52 mm, 4.10 ± 1.02 mm vs. 4.65 ± 0.78 mm, 6.11 ± 1.12 mm vs. 6.88 ± 1.03 mm, and 9.72 ± 1.95 mm vs. 10.70 ± 1.55 mm for 1, 2, 5 and 10 mm below MS, respectively, P < 0.05 for all). Multivariable logistic regression analysis showed that pre-procedural IVS thickness (<4 mm at 2 mm below the MS) was a significant independent predictor of post-procedural conduction disturbance (adjOR 7.387, 95% CI: 2.003-27.244, P = 0.003). CONCLUSION: Pre-procedural CT assessment of basal IVS thickness is a novel predictive marker for the risk of conduction disturbances following TAVR. The IVS thickness potentially acts as an anatomical barrier protecting the underlying conduction system from mechanical compression during TAVR.

Differential Effect of Aortic Valve Replacement for Severe Aortic Stenosis on Hyperemic and Resting Epicardial Coronary Pressure Indices.

BACKGROUND: Coronary pressure indices to assess coronary artery disease are currently underused in patients with aortic stenosis due to many potential physiological effects that might hinder their interpretation. Studies with varying sample sizes have provided us with conflicting results on the effect of transcatheter aortic valve replacement (TAVR) on these indices. The aim of this meta-analysis was to study immediate and long-term effects of TAVR on fractional flow reserve (FFR) and nonhyperemic pressure ratios (NHPRs). METHODS AND RESULTS: Lesion-specific coronary pressure data were extracted from 6 studies, resulting in 147 lesions for immediate change in FFR analysis and 105 for NHPR analysis. To investigate the long-term changes, 93 lesions for FFR analysis and 68 for NHPR analysis were found. Lesion data were pooled and compared with paired t tests. Immediately after TAVR, FFR decreased significantly (-0.0130±0.0406 SD, P: 0.0002) while NHPR remained stable (0.0003±0.0675, P: 0.9675). Long-term after TAVR, FFR decreased significantly (-0.0230±0.0747, P: 0.0038) while NHPR increased nonsignificantly (0.0166±0.0699, P: 0.0543). When only borderline NHPR lesions were considered, this increase became significant (0.0249±0.0441, P: 0.0015). Sensitivity analysis confirmed our results in borderline lesions. CONCLUSIONS: TAVR resulted in small significant, but opposite, changes in FFR and NHPR. Using the standard cut-offs in patients with severe aortic stenosis, FFR might underestimate the physiological significance of a coronary lesion while NHPRs might overestimate its significance. The described changes only play a clinically relevant role in borderline lesions. Therefore, even in patients with aortic stenosis, an overtly positive or negative physiological assessment can be trusted.

Assess the Outcomes of Transcatheter Aortic Valve Replacement in Bicuspid Valve with Mixed Disease versus Predominant Aortic Stenosis.

Purpose: In mixed aortic valve disease (MAVD), the results of transcatheter aortic valve replacement (TAVR) are conflicting. There is limited data on the outcomes of TAVR in patients with bicuspid aortic valve (BAV) and MAVD. The objective of this study is to compare outcomes after TAVR in BAV patients with MAVD and predominant aortic stenosis (PAS). Patients and Methods: Patients with BAV who underwent TAVR between January 2016 and April 2023 were included. The primary outcome was device success. The secondary endpoints were periprocedural mortality and other complications as defined by the Valve Academic Research Consortium-3 (VARC-3). Propensity score matching was used to minimize potential confounding. Results: A total of 262 patients were included in this study, 83 of whom had MAVD. The median age was 72 years, and 55.7% were male. The baseline comorbidity risk files were comparable between the two groups. Patients with MAVD had more mitral regurgitation, tricuspid regurgitation and pulmonary hypertension, larger annular and left ventricular outflow tract dimensions, and more severe calcification than PAS. In the unmatched population, MAVD patients had similar device success rate (69.9% vs 79.9%, P=0.075) and 30-day mortality (3.6% vs 3.4%, P=1) compared to PAS. Propensity score matching resulted in 66 patient pairs. Device success rate were still comparable in the matched population. Other clinical outcomes, including stroke, bleeding (type 2-4), major vascular complications, acute kidney injury (stage 2-4) and permanent pacemaker implantation, were comparable between the two groups. Multivariable logistic regression analysis did not show MAVD to be an independent negative predictor of device success. At one year, survival was similar between patients with MAVD and those with PAS. Conclusion: For the bicuspid valve, patients with MAVD had a more challenging anatomy. MAVD patients associated with comparable 30-day clinical outcomes after TAVR compared to PAS patients in patients with BAV.

[Perioperative stroke after aortic valve replacement for aortic stenosis - incidence, risk factors and short-term outcome].

INTRODUCTION: One of the most serious complications of surgical aortic valve replacement (SAVR) is stroke that can result in increased rates of complications, morbidity and mortality postoperatively. The aim of this study was to investigate incidence, risk factors and short-term outcome in a well defined cohort of SAVR-patients. MATERIALS AND METHOD: A retrospective study on 740 consecutive aortic stenosis patients who underwent SAVR in Iceland 2002-2019. Patients with stroke were compared with non-stroke patients; including preoperative risk factors of cardiovascular disease, echocardiogram-results, rate of early postoperative complications other than stroke and 30 day mortality. RESULTS: Mean age was 71 yrs (34% females) with 57% of the patients receiving stented bioprosthesis, 31% a stentless Freestyle®-valve and 12% a mechanical valve. Mean EuroSCORE-II was 3.6, with a maximum preop-gradient of 70 mmHg and an estimated valvular area of 0.73 cm2. Thirteen (1.8%) patients were diagnosed with stroke where hemiplegia (n=9), loss of consciousness (n=3) and/or aphasia (n=4) were the most common presenting symptoms. In 70% of cases the neurological symptoms resolved or disappeared in the first weeks and months after surgery. Only one patient out of 13 died within 30-days (7.7%). Stroke-patients had significantly lower BMI than non-stroke patients, but other risk factors of cardiovascular diseases, intraoperative factors or the rate of other severe postoperative complications than stroke were similar between groups. Total length of stay was 14 days vs. 10 days median, including 2 vs. 1 days in the ICU, in the stroke and non-stroke-groups, respectively. CONCLUSIONS: The rate of stroke after SAVR was low (1.8%) and in line with other similar studies. Although a severe complication, most patients with perioperative stroke survived 30 days postoperatively and in majority of cases neurological symptoms recovered.

Angulation and curvature of aortic landing zone affect implantation depth in transcatheter aortic valve implantation.

In transcatheter aortic valve implantation (TAVI), final device position may be affected by device interaction with the whole aortic landing zone (LZ) extending to ascending aorta. We investigated the impact of aortic LZ curvature and angulation on TAVI implantation depth, comparing short-frame balloon-expanding (BE) and long-frame self-expanding (SE) devices. Patients (n = 202) treated with BE or SE devices were matched based on one-to-one propensity score. Primary endpoint was the mismatch between the intended (HPre) and the final (HPost) implantation depth. LZ curvature and angulation were calculated based on the aortic centerline trajectory available from pre-TAVI computed tomography. Total LZ curvature ( k L Z , t o t ) and LZ angulation distal to aortic annulus ( α L Z , D i s t a l ) were greater in the SE compared to the BE group (P < 0.001 for both). In the BE group, HPost was significantly higher than HPre at both cusps (P < 0.001). In the SE group, HPost was significantly deeper than HPre only at the left coronary cusp (P = 0.013). At multivariate analysis, α L Z , D i s t a l was the only independent predictor (OR = 1.11, P = 0.002) of deeper final implantation depth with a cut-off value of 17.8°. Aortic LZ curvature and angulation significantly affected final TAVI implantation depth, especially in high stent-frame SE devices reporting, upon complete release, deeper implantation depth with respect to the intended one.

Comparison of apixaban versus aspirin for the prevention of latent bioprosthetic aortic valve thrombosis: study protocol for a prospective randomized trial.

BACKGROUND: The optimal antithrombotic strategy early after aortic valve replacement surgery with a biological valve remains controversial due to lack of high-quality evidence. Either oral anticoagulants or acetylsalicylic acid should be considered for the first 3 months. Hypo-attenuated leaflet thickening on cardiac computed tomography has been associated with latent bioprosthetic valve thrombosis and may be prevented with anticoagulation. We hypothesize that anticoagulation with apixaban is superior to single antiplatelet therapy with acetylsalicylic acid in reducing hypo-attenuated leaflet thickening of bioprosthetic aortic valve prostheses. METHODS: In this prospective, open-label, randomized trial, patients undergoing isolated aortic valve replacement surgery with rapid deployment bioprosthetic valves will be randomized. The treatment group will receive 5 mg of apixaban twice a day for the first 3 months and 100 mg of acetylsalicylic acid thereafter. The control group will be administered 100 mg of acetylsalicylic acid once a day, indefinitely. After the 3-month treatment period, a contrast-enhanced electrocardiogram-gated cardiac computed tomography will be performed to identify hypo-attenuated leaflet thickening of the bioprosthetic valve. The primary objective of the study is to assess the impact of apixaban on the prevention of hypo-attenuated leaflet thickening at 3 months. The secondary and exploratory endpoints will be clinical outcomes and safety profiles of the two strategies. DISCUSSION: Antithrombotic therapy after aortic valve replacement is used to prevent valve thrombosis and systemic thromboembolism. Latent bioprosthetic valve thrombosis is a precursor of clinically significant prosthetic valve dysfunction or thromboembolic events. The hallmark feature of latent bioprosthetic valve thrombosis is hypo-attenuated leaflet thickening on cardiac computed tomography. Subclinical leaflet thrombosis occurs frequently in bioprosthetic aortic valves, more commonly in transcatheter than in surgical valves. There is no evidence on the effect of direct oral anticoagulants on the incidence of hypo-attenuated leaflet thickening after surgical aortic valve replacement with rapid deployment bioprostheses. TRIAL REGISTRATION: ClinicalTrials.gov NCT06184113. Registered on December 28, 2023.