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OBJECTIVES Available apical occluders do not fulfil requirements for full-percutaneous transapical valve procedures with large-sized introducer sheaths. A self-expanding closure device designed for closed-chest transapical valve procedures was tested in an animal model to verify safety, efficacy and thrombogenicity. METHODS Large-sized 21-Fr introducer sheaths (Certitude™ system for Sapien™ valves) were percutaneously placed in the ventricles of nine 3-month old minipigs. To seal the apical access, delivery catheters carrying folded self-expanding plugs were inserted. Then, the plugs were deployed while sheaths were removed. Echocardiograms verified tamponade and cardiac function, drains were not placed and a 3-month long aspirin therapy was administered. After 6 and 9 months, animals were euthanized and organs were analysed for macroembolic lesions search. Histological analysis was also performed. RESULTS Nine minipigs (weight: 28±3 kg) were used for this study. Eight plugs were successfully deployed in 8 ventricles without cardiac tamponade or ventricular dysfunction (success rate: 88.9%). In a failed procedure (the animal died after 1 month of cardiac tamponade), the outer disc of the apical plug got stuck in the intercostal space and did not correctly deploy. Post-mortem analysis in 8 minipigs at 6 (n = 4) and 9 months (n = 4) confirmed full deployment and good fixation of all plugs with internal surfaces covered by new endocardium. Macroscopic analysis of myocardium and vital organs showed absence of embolic lesions. Histological analysis showed absence of significant inflammatory infiltration and thrombosis. CONCLUSIONS In this animal model, self-expanding closure devices sealed 21-Fr large percutaneous apical accesses without acute tamponade, thrombosis or embolization. Further tests to evaluate full-percutaneous closed-chest apical procedures are required.

OBJECTIVES Transcatheter aortic root repair (TARR) consists of the simultaneous endovascular replacement of the aortic valve, the root and the proximal ascending aorta. The aim of the study is to set-up a computational model of TARR to explore the impact of the endovascular procedure on the coronary circulation supported by chimney grafts. METHODS Computed tomography of a patient with dilated ascending aorta was segmented to obtain a 3-dimensional representation of the proximal thoracic aorta, including aortic root and supra-aortic branches. Computed assisted design tools were used to modify the geometry to create the post-procedural TARR configuration featuring the main aortic endograft integrated with 2 chimney grafts for coronary circulation. Computational Fluid Dynamics simulations were run in both pre- and post-procedural configurations using a pulsatile inflow and lumped parameter models at the outflows to simulate peripheral aortic and coronary circulation. Differences in coronary flow and pressure along the cardiac cycle were evaluated. RESULTS After the virtual implant of the TARR device with coronary grafts, the flow became more organized and less recirculation was seen in the ascending aorta. Coronary perfusion was guaranteed with negligible flow differences between pre- and post-procedural configurations. However, despite being well perfused by chimney grafts, the procedure induces an increase of the pressure drop between the coronary ostia and the ascending aorta of 8 mmHg. CONCLUSIONS The proposed numerical simulations, in the specific case under investigation, suggest that the TARR technique maintains coronary perfusion through the chimney grafts. This study calls for experimental validation and further analyses of the impact of TARR on cardiac afterload, decrease of aortic compliance and local pressure drop induced by the coronary chimney grafts.

OBJECTIVES Transfemoral approach is the standard access-route for transcatheter aortic valve replacement (TAVR). However, alternative approaches are needed in a number of patients and accesses such as transapical (TA) TAVR or transcervical (TC) are used. We aimed to compare clinical and echocardiographic outcomes after TA-TAVR or TC-TAVR. METHODS All patients who underwent TA- and TC-TAVR for severe aortic stenosis in our institution between 2008 and 2020 were retrospectively included. End points included 30-day all-cause mortality, procedural complications (according to the Valve Academic Research Consortium-2 criteria), procedure duration, intensive care unit (ICU) length of stay (LOS) and overall hospital LOS. For 30-day all-cause mortality, we furthermore used a Cox proportional-hazards model to adjust for significant between-group differences in baseline characteristics as well as difference in year of intervention. RESULTS TAVR was performed in 176 patients, using a TA approach (n = 127) or a TC approach (n = 49). Baseline clinical and echocardiographic characteristics were comparable between the 2 groups, except age and peripheral artery disease. All-cause 30-day mortality rates were not significantly different (8.5% in the TA group vs 2.3% in the TC group, P = 0.124). TC approach was associated with significantly shorter procedure duration {71.0 [interquartile range (IQR) 52.5–101.0] vs 93 [IQR 80.0–120.0] min, P CONCLUSIONS The TC approach may be a good first-choice alternative in case of contraindications to transfemoral-TAVR.

OBJECTIVES Transcatheter aortic root repair is still not available because of the technical challenge of coronary perfusion. The use of chimney grafts for coronary ostia can be an option and we tested the flow-through coronary chimney grafts deployed in a 3-dimensional-printed root model as part of a transcatheter aortic root repair system. METHODS A 3-dimensional-printed root was used to test the coronary flow after the deployment of 1 root endograft (28 mm diameter) and two 6-mm diameter 10-cm long coronary chimney grafts. Continuous coronary flows were measured in a bench test at different pressure levels (60, 80 and 100 mmHg) and compared to target coronary flows (250 ml/min at rest for the left and 150 ml/min at rest for the right coronary artery). RESULTS The computed tomography scan-based root was modified with two 5-mm diameter coronary conduits to overcome the limits of the original 3-dimensional-printed coronary ostia. The root was placed in the hydrodynamic system: adjusted coronary free flow at 60, 80 and 100 mmHg of pressure was 1913, 2200 and 2480 ml/min for left coronary and 1633, 2026 and 2366 ml/min for right coronary, respectively. After endografts deployment, mean chimney graft flow at 60, 80 and 100 mmHg of pressure was 1053 ml/min (−45%), 1306 ml/min (−41%) and 1502 ml/min (−40%) for the left coronary and 1100 ml/min (−33%), 1460 ml/min (−28%) and 1626 ml/min (−31%) for the right coronary, respectively. CONCLUSIONS In this preliminary study, chimney grafts for transcatheter aortic root repair provided 830% of target flow in the right coronary (−31% of free flow) and 414% of target flow in the left coronary (−42% of free flow) which is more than sufficient for both coronaries in real-life conditions. The potential of this approach should be further explored with specifically designed endografts.

Delayed aortic regurgitation following Valsalva sinus re-dissection is a well-known complication that can occur at any time after surgery for type-A aortic dissection without root replacement. We describe a case of acute type-A dissection in an 81-year-old lady successfully treated with aortic valve resuspension and ascending aorta replacement with a 28-mm vascular graft. A month later, the patient was readmitted for worsening heart failure and a transthoracic echocardiogram showed severe aortic regurgitation secondary to non-coronary Valsalva sinus re-dissection and non-coronary aortic valve leaflet prolapse also confirmed at computed tomography scan. The patient successfully underwent a transfemoral transcatheter aortic valve implantation with a 29-mm CoreValve Evolut R and concomitant planned extracorporeal membrane oxygenation support.

Objectives The goal was to show the technical details, feasibility and clinical results of balloon-expandable stent valve implantation in the aortic position during conventional redo open-heart surgery in selected obese patients with a small aortic prosthesis and severe patient-prosthesis mismatch. Methods Two symptomatic overweight patients (body mass index of 31 and 38), each with a small aortic prosthesis (a 4-year-old, 21-mm Hancock II biological valve and a 29-year-old, 23-mm Duromedic mechanical valve), increased transvalvular gradients (59/31 and 74/44 mmHg) and a reduced indexed effective orifice area (0.50 and 0.43 cm 2 /m 2 ) underwent implantation of two 26-mm balloon-expandable Sapien 3 valves during standard on-pump redo valve surgery. Results Using full re-sternotomy, cardiopulmonary bypass and cardioplegic arrest, the two balloon-expandable stent valves were implanted under direct view using a standard aortotomy, after prosthesis removal and without annulus enlargement. Aortic cross-clamp times were 162 and 126 min; cardiopulmonary bypass times were 178 and 180 min; total surgical times were 360 and 318 min. At discharge, echocardiograms showed transvalvular peak and mean gradients of 13/9 and 23/13 mmHg and indexed effective orifice areas of 0.64 and 1.08 cm 2 /m 2 . The 3-month echocardiographic follow-up showed transvalvular peak and mean gradients of 18/9 and 19/11 mmHg and indexed effective orifice areas of 0.78 cm 2 /m 2 and 0.84 cm 2 /m 2 , with improved symptoms (New York Heart Association class 1). Conclusions Implantation of a balloon-expandable stent valve during redo aortic valve surgery is feasible in selected cases and prevents patient-prosthesis mismatch in obese patients without need for aortic annulus enlargement. Moreover, in the case of stent valve degeneration, this approach permits additional valve-in-valve procedures with large stent valves and prevents re-redo surgery.