Comparison of 4 mortality scores for surgical repair of type A aortic dissection: a multicentre external validation.

OBJECTIVES: In the last decades, 4 different scores for the prediction of mortality following surgery for type A acute aortic dissection (TAAD) were proposed. We aimed to validate these scores in a large external multicentre cohort. METHODS: We retrospectively analysed patients who underwent surgery for TAAD between 2000 and 2020. Patients were enrolled from 10 centres from 2 European countries. Outcomes were the early (30-day and/or in-hospital) and 1-year mortality. Discrimination, calibration and observed/expected (O/E) ratio were evaluated. RESULTS: A total of 1895 patients (31.7% females, mean age 63.72 ± 12.8 years) were included in the study. Thirty-day mortality and in-hospital mortality were 21.7% (n = 412) and 22.5% (n = 427) respectively. The German Registry of Acute Aortic Dissection Type A (GERAADA) score shows to have the best discrimination [area under the curve (AUC) 0.671 and 0.672] in predicting as well the early and the 1-year mortality, followed by the International Registry of Acute Aortic Dissection (IRAD) model 1 (AUC 0.658 and 0.672), the Centofanti (AUC 0.645 and 0.66) and the UK aortic score (AUC 0.549 and 0.563). According to Hosmer-Lemeshow and Brier tests, the IRAD model I and GERAADA, respectively, were well calibrated for the early mortality, while the GERAADA and Centofanti for the 1-year mortality. The O/E analysis showed a marked underestimation for patients labelled as low-risk for UK aortic score and IRAD model I for both outcomes. CONCLUSIONS: The GERAADA score showed the best performance in comparison with other scores. However, none of them achieved together a fair discrimination and a good calibration for predicting either the early or the 1-year mortality.

Coronary Perfusion After Valve-in-Valve Transcatheter Aortic Valve Implantation in Small Aortic Root: In Vitro Experimental Assessment.

Coronary flow obstruction following transcatheter aortic valve-in-valve implantation (VIV-TAVI) is associated with a high mortality risk. The aim of this work was to quantify the coronary perfusion after VIV-TAVI in a high-risk aortic root anatomy. 3D printed models of small aortic root were used to simulate the implantation of a TAVI prosthesis (Portico 23) into surgical prostheses (Trifecta 19 and 21). The aortic root models were tested in a pulsatile in vitro bench setup with a coronary perfusion simulator. The tests were performed at baseline and post-VIV-TAVI procedure in aligned and misaligned commissural configurations under simulated hemodynamic rest and exercise conditions. The experimental design provided highly controllable and repeatable flow and pressure conditions. The left and right coronary mean flow did not differ significantly at pre- and post-VIV-TAVI procedure in any tested configurations. The commissural misalignment did not induce any significant alterations to the coronary flow. High-risk aortic root anatomy did not trigger coronary ostia obstruction or coronary flow alteration after transcatheter aortic valve implantation in a surgical bioprosthesis as shown from in-vitro flow loop tests.

Morphometric Characterization of an Ex Vivo Porcine Model of Functional Tricuspid Regurgitation.

Emerging treatments for tricuspid valve (TV) regurgitation require realistic TV pathological models for preclinical testing. The aim of this work was to investigate structural features of fresh and defrosted porcine right-heart samples as models of mild and severe functional tricuspid regurgitation (FTR) condition in ex-vivo pulsatile flow platform. Ten fresh hearts were tested ex-vivo under steady and pulsatile flow in typical right-heart loading conditions. Hemodynamics and 3D echocardiographic imaging of TV and right ventricle (RV) were acquired. Hearts were then kept frozen for 14 days, defrosted, and tested again with the same protocol. Morphometric parameters of TV and RV were derived from 3D reconstructions based on echo data. Fresh samples showed a slightly dilated TV morphology, with coaptation gaps among the leaflets. Sample freezing induced worsening of TV insufficiency, with significant (p < 0.05) increases in annulus size (annulus area and perimeter 7.7-3.1% respectively) and dilation of RV (9.5%), which led to an increase in tenting volume (123.7%). These morphologic alterations reflected into a significant increment of regurgitation fraction (27%). Together, such results suggest that fresh porcine heart samples may be a reliable ex-vivo model of mild FTR condition, which can be enhanced through freezing/thawing treatment to model a severe pathological condition.

Lithotripsy of Calcified Aortic Valve Leaflets by a Novel Ultrasound Transcatheter-Based Device.

The increasing incidence of calcific aortic valve disease necessitates the elaboration of new strategies to retard the progression of the pathology with an innovative solution. While the increasing diffusion of the transcatheter aortic valve replacements (TAVRs) allows a mini-invasive approach to aortic valve substitution as an alternative to conventional surgical replacement (SAVR) in an always larger patient population, TAVR implantation still has contraindications for young patients. In addition, it is liable to undergo calcification with the consequent necessity of re-intervention with conventional valve surgery or repeated implantation in the so-called TAVR-in-TAVR procedure. Inspired by applications for non-cardiac pathologies or for vascular decalcification before stenting (i.e., coronary lithotripsy), in the present study, we show the feasibility of human valve treatment with a mini-invasive device tailored to deliver shockwaves to the calcific leaflets. We provide evidence of efficient calcium deposit ruptures in human calcified leaflets treated ex vivo and the safety of the treatment in pigs. The use of this device could be helpful to perform shockwaves valvuloplasty as an option to retard TAVR/SAVR, or as a pretreatment to facilitate prosthesis implantation and minimize the occurrence of paravalvular leak.

Commissural repositioning in bicuspid aortic valve repair: an in vitro acute model to explore and explain different results.

OBJECTIVES: Commissural orientation <160° is a recognized risk factor for bicuspid aortic valve repair failure. Based on this observation, repairing this subtype of aortic valve by reorienting the 2 commissures at 180° has recently been proposed. METHODS: Nine porcine hearts with aortic annulus diameters of 25 mm were selected. A pathological model of a Sievers 1 bicuspid aortic valve was obtained by suturing the coaptation line between the left and right leaflets. Each heart underwent reimplantation procedures both in the native (120°) and the reoriented (180°) configuration. After the operation, each sample was tested on a pulse duplicator at rest (heart rate 60 beats per min) and with mild exercise (heart rate 90 beats per min) conditions. RESULTS: No statistically significant difference was noted in mean and peak transvalvular aortic gradients between the 2 configurations at rest (18.6 ± 5 vs 17.5 ± 4 for the mean aortic gradient; 42.8 ± 12.7 vs 36.3 ± 5.8 for the peak aortic gradient) but the group with the 120°-oriented commissures had significantly higher mean transaortic gradients compared to the group with the 180°-oriented commissures at initial exercise stress conditions (30.1 ± 9.1 vs 24.9 ± 3.8; p value 0.002). CONCLUSIONS: The 180° commissural reorientation of the asymmetrical bicuspid aortic valve does not improve the transvalvular aortic gradient in an acute model at rest conditions, but it could do so under stress situations. Even if it is surgically more complex and time-consuming, this approach could be a good strategy to improve long-term results, particularly in young patients.

Hybrid Surgery to Manage Aortic Arch Pathology.

Background and Objectives: Aortic arch disease is still a high-risk surgical challenge despite major advances both in surgical and anesthesiological management. A combined surgical and endovascular approach has been proposed for aortic arch disease treatment to avoid hypothermia and circulatory arrest in high-risk patients. Materials and Methods: Between June 2004 and June 2021, 112 patients were referred to our department for aortic arch surgery; 38 (33.9%) patients underwent supra-aortic debranching and endovascular treatment. Of these, 21 (55%) patients underwent type I aortic arch hybrid debranching procedure and in 17 (45%) patients a type II aortic arch hybrid debranching procedure was performed. None of the patients were emergent. Results: No intra-operative deaths were recorded. In the type I aortic arch hybrid debranching patients' group, one patient died at home waiting the endovascular step, one developed ascending aortic dissection and another one developed a pseudoaneurysm at the site of the debranching at follow-up. In the type II aortic arch hybrid debranching patients' group, left carotid artery branch closure was detected at follow-up in one patient. Thirty day/in-hospital rates of adverse neurological events for both the surgical and endovascular procedures were 3% for minor stroke, with no permanent neurological deficit and 0% for permanent paraplegia/paraparesis. In 100% of the cases, the endovascular step succeeded and the type Ia endoleak rate was 0%. Conclusions: Hybrid arch surgery is a valuable option for aortic arch aneurysm treatment in patients with high surgical risk. The choice of aortic arch debranching between type I or type II is crucial and depends on anatomic and clinical patient characteristics. Further larger scale studies are needed to better define the advantages of these techniques.

Open supra-aortic revascularization and arch reconstruction after previous TEVAR in a complex arch anatomy.

We propose a technique to minimize the neurological and systemic risks involved in rerouting the blood flow toward the brain in a "single remaining vessel" configuration with a 90% stenosis by means of complete hypothermic cerebral protection associated with normothermic systemic blood flow with a "restitutio ad integrum" of the supra-aortic trunks flow. The perfusion of the brain and the arms was almost completely separated from the systemic perfusion by the deployment 1 year before of a thoracic endoprosthesis in association with complete chronic occlusion of the brachiocephalic trunk and a functioning carotid-subclavian bypass. The Free Flow of the prosthesis, which acted as a hook, moved the calcium toward the left carotid ostium, creating a 90% stenosis with intermittent acute cerebral hypoperfusion and amaurosis. We achieved an optimal result: The patient was discharged on postoperative day 7 with no neurological problems and with patency and direct blood flow in all the supra-aortic trunks.

How to recycle a misused left internal thoracic artery: Tips and tricks.

In this case report, we describe how to recycle the left internal thoracic artery (LITA) when misused but not damaged. Eight years after a left anterior small thoracotomy followed by left anterior descending (LAD) stenting for STEMI in first postoperative day, a 67-years-old woman had an NSTEMI with angiographic evidence of intrastent re-stenosis with a perfectly patent LITA, harvested only from the fourth to the sixth intercostal space. During redo surgery, LITA was harvested as a pedicle from the anastomosis to the fourth intercostal space and primarily from the first to the fourth intercostal space. Special attention was paid at the level of the fourth intercostal space where the vessel was stuck to the sternum: a 15-blade was used being scissors or cautery too dangerous. At the end of harvesting, the LITA was full-length available for a new coronary anastomosis on LAD, distal to the previous one.

Hybrid endovascular/surgical Kommerrell's diverticulum treatment.

Kommerrell's diverticulum of the right aberrant subclavian artery is a rare disease, its treatment is still controversial. We report the case of a patient with a six cm aneurysmal dilation successfully treated in a hybrid surgical/endovascular way.

Hybrid repair of extensive thoracic aortic aneurysms.

OBJECTIVES: Our goal was to report the midterm results of hybrid treatment of extensive thoracic aortic aneurysm (ETAA) with the completion of thoracic endovascular aortic repair after proximal ascending-arch graft replacement. METHODS: This was a multicentre, observational study. Data were collected prospectively between January 2002 and March 2019 and analysed retrospectively. Inclusion criteria for the final analysis were the treatment of elective or urgent ETAA performed in a single-stage or a planned two-stage approach. Early and late survival rates were the primary outcomes. RESULTS: Indications for repair were degenerative ETAA in 27 (64.3%) patients and dissection-related ETAA in 15 (35.7%). The mean aortic diameter was 68 ± 16 mm (interquartile range 60-75). Five (11.9%) patients had a single-stage repair; and 37 underwent a two-stage approach. Three (7.1%) patients died in-hospital. The median follow-up was 49 months (range 0-204). During the follow-up period, 4 (9.5%) patients underwent aortic reintervention after a median of 32 months; however, no aortic rupture of the treated segment occurred. Overall, the estimated survival rate was 85% ± 6% [95% confidence interval (CI) 70.8-93] at 12 and 36 months and 69.5% ± 9% (95% CI 49.7-84) at 60 months. CONCLUSIONS: Hybrid repair of ETAA had satisfactory early results in this cohort of patients. At the midterm follow-up, the aneurysm-related mortality rate was acceptable with the reconstruction proving to be durable and safe with few distal aortic events.

Effect of the valve design on pressure drop, pressure recovery, and spatial positioning of vena contracta.

BACKGROUND: Bioprostheses are complex structures and yield a very complex fluid dynamics. Hence, it can be hypothesized that prosthesis structural characteristics affect the position of the vena contracta and, consequently, influences the pattern and the extent of pressure recovery downstream from the vena contracta. MATERIALS AND METHODS: The study was performed on pericardial aortic prostheses, specifically Crown 21 and 23 (LivaNova PLC, UK), Trifecta 19 and 21 (Edwards Lifescience, USA), and Magna 19 and 21(Abbott, USA), tested in an "ad hoc" devised steady flow loop circuit at four flow rates (10, 15, 20, and 25 L/min). Fluid dynamic quantities were obtained by direct pressure measurement and Doppler interrogation. RESULTS: Pressure drop at 25 L/min flow rate was 26.5 ± 0.3 mm Hg and 14.9 ± 0.1 mm Hg for the Trifecta 19 and 21, 37.1 ± 1.0 mm Hg and 27.3 ± 0.4 mm Hg for the Magna 19 and 21, and 36.6 ± 1.0 mm Hg and 22.7 ± 0.1 mm Hg for Crown 21 and 23, respectively. The vena contracta was shorter for Trifecta compared with the Magna and the Crown in which it developed further downstream and as far as 1 cm from the valve leaflets fringes. The pressure recovery was 54% ± 1% for Trifecta 21, 39% ± 1% for Magna 21, and 41% ± 2% for Crown 23 with different patterns. CONCLUSION: The design of bioprosthesis affects pressure recovery and the position of the vena contracta. The different patterns of pressure recovery might have clinical impact.

Optilene, a new non-absorbable monofilament is safe and effective for CABG anastomosis. OPTICABG - A prospective international, multi-centric, cohort study.

INTRODUCTION: Coronary artery bypass grafting (CABG) is performed to improve quality of life and to reduce cardiac-related mortality and morbidity in patients with coronary artery disease (CAD). The aim of the present observational study was to assess the performance of a new suture material (Optilene) for anastomosis construction in CABG surgery using a routine clinical procedure. Performance was assessed using the incidence of major adverse cardiac and cerebrovascular events (MACCE). METHODS: The study was designed as an international, multi-centre, prospective cohort study to evaluate the safety and efficacy of a new non-absorbable monofilament for CABG surgery compared to data published in a previous meta-analysis. Optilene suture was used to create the distal and proximal coronary artery anastomoses. The primary endpoint was the cumulative MACCE rate up to discharge. Secondary parameters were intraoperative handling of the suture material and QoL up to 3 months after surgery. Patients were examined 30 days and 3 months postoperatively. RESULTS: In total, 199 patients were enrolled in 3 centres in Europe. The cumulative CABG adverse event rate up to the day of discharge was 3%, in contrast to the 8.46% given by the data generated by Nalysnyk et al. A t-test showed that our CABG rate was significantly lower. QoL significantly increased from preoperatively until 3 months after surgery. Ease of handling the suture material was rated as very good. CONCLUSION: Optilene suture material represents a safe and effective alternative to existing sutures used in CABG surgery for anastomosis construction.

Surgical Treatment of Synchronous Type B Acute Aortic Dissection and Abdominal Aortic Aneurysm.

BACKGROUND: We report the results of the operative treatment of synchronous type B acute aortic dissection (TBAAD) and infrarenal abdominal aortic aneurysm (AAA). METHODS: It is an observational, descriptive multicenter case series. Inclusion criterion was patients with diagnosis of TBAAD and AAA detected synchronously for the first time at clinical onset of dissection. Follow-up imaging protocol included triple-phase spiral/computed tomography angiography performed at 1, 6, and 12 months after thoracic endovascular aortic repair (TEVAR), and annually thereafter. Major end points were perioperative mortality and long-term survival, freedom from aortic events, and freedom from reintervention. RESULTS: We identified and treated 15 cases. All TBAADs were treated by TEVAR in the acute phase: infrarenal aortic repair was performed with stent graft (SG) in 10 (66.7%) patients, with open repair in 5 (33.3%). Overall, staged repair was used in 11 (73.3%) patients. Mean descending aortic endovascular length coverage was 21 cm ± 7 (range, 10-35; interquartile range [IQR], 150-265). Overall, early perioperative mortality occurred in 1 (6.7%) patient. Median radiologic follow-up was 48 months (range, 6-120; IQR, 36-67). During the follow-up, TEVAR-related mortality was not observed. Aortic remodeling after TEVAR was obtained in 12 (85.7%) patients; abdominal sac shrinkage after SG was obtained in 8 (80.0%) patients. Freedom from aortic event rate was 79% ± 10 (95% confidence interval [CI]: 53.1-92.6) at 1 year and 64% ± 13 (95% CI: 38.1-83.5) at 5 year. Freedom from reintervention rate at 1 and 5 year was 85% ± 10 (95% CI: 57.8-95.7). CONCLUSIONS: In our experience, the association of TBAAD and AAA was a rare finding. Because of the lack of available evidence to opt for a single intervention or a staged approach, selective approach with TEVAR and endovascular/open conventional treatment of the abdominal aorta yielded satisfactory results at midterm follow-up.

Hydrodynamic and Geometric Behavior of Two Pericardial Prostheses Implanted in Small Aortic Roots.

Hydrodynamic performance of stented bioprostheses is far below that of the native valve. One of the reasons is that the internal diameter of the prosthesis is usually smaller than that of the native valve. However, other valve characteristics are also important in generating the pressure drop. We aimed to assess, in an ex vivo pulsatile mock loop, the hydrodynamic behavior of two bioprostheses, Trifecta and Mitroflow, to ascertain which geometric terms are limiting factors in hydrodynamic performance. At stroke volumes between 30 and 60 ml, Trifecta showed lower pressure drop, energy dissipation and valve resistance, and greater effective orifice area. This trend was overturned at higher stroke volumes, with Mitroflow slightly outperforming Trifecta. The geometric determinants were consistent with these results. Trifecta achieved its maximum opening area already at the lowest stroke volumes, featuring a divergent shape at the systolic peak. Mitroflow showed a complex opening pattern, featuring a convergent shape at the systolic peak for lower stroke volumes, while reaching its maximum opening area at higher stroke volumes, with a divergent shape. The two bioprostheses, although similar in design, displayed different biomechanical behaviors. The internal diameter of each bioprosthesis did not show to be strictly correlated with its hydrodynamic characteristics.

MitraClip removal: surgical techniques to preserve native mitral valve leaflets.

Transcatheter valve procedures are wide-spreading techniques for the treatment of heart valves pathologies. In case of implantation failure, the transcatheter device often needs to be removed. This procedure, which can alter the biological structure integrity, can limit the option available for the subsequent traditional surgery. One of the most popular devices for transcatheter mitral valve repair is the MitraClip system. In this work, we describe 2 different techniques for the surgical removal of MitraClip. These techniques aim to preserve the valve leaflets integrity, to allow for subsequent mitral valve surgical repair.

Modelling of Lesions Associated with Functional Mitral Regurgitation in an Ex Vivo Platform.

Functional mitral regurgitation (FMR) is a complex pathology involving valvular and subvalvular structures reconfiguration, and its treatment is considered challenging. There is a lack of experimental models allowing for reliable preclinical FMR treatments' evaluation in a realistic setting. A novel approach to simulate FMR was developed and incorporated into an ex vivo passive beating heart platform. FMR was obtained by dilating the mitral annulus (MA) mainly in the antero-posterior direction and displacing the papillary muscles (PMs) apically and laterally by ad hoc designed and 3D printed dilation and displacing devices. It caused hemodynamic and valve morphology alterations. Isolated MA dilation (MAD) led to significantly increased antero-posterior distance (A-P) and decreased coaptation height (CH), tenting area (TA) and systolic leaflets angulation, resembling clinically recognized type I of mitral regurgitation with normal leaflet motion. Whereas concomitant MAD with PM displacement caused an increase in A-P, TA, CH. This geometrical configuration replicated typical determinants of type IIIb lesion with restricted leaflet motion. The proposed methods provided a realistic and repeatable ex vivo FMR model featuring two lesions clinically associated with the pathology. It bears a promise to be successfully utilized in preclinical studies, clinical training and medical education.

A novel system for the treatment of aortic annular dilation: an ex vivo investigation.

OBJECTIVES: The main reason for aortic repair failures is recurrent annular dilatation. The fibrous portion of left ventricular outflow tract dilates. A novel device was designed to tackle this problem. METHODS: The device consists of an internal ring applied at the aortic annulus plus an external flexible band at the level of the aortic root. The internal ring has a semi-rigid portion (40%, placed at ventriculo-arterial junction) and a flexible portion to allow it to conform along the curves of the non-coronary/right coronary leaflet and right coronary/left coronary leaflet commissures. The external band acts as a reinforcement to the internal ring. A pulsatile mock loop capable of housing porcine aortic valve was used. Working conditions were 60 bpm of heart rate, 75 of stroke volumes and 120-80 mmHg of simulated pressure. Mean gradient, effective orifice area, annular diameter, coaptation height and length were recorded on 11 aortic root units (ARUs). High-speed video and standard echocardiographic images were also recorded. All data were acquired in the following conditions: (i) basal (untreated ARU); (ii) pathological condition (left coronary/non-coronary triangle was dilated by suturing an aortic patch); and (iii) ARU treated with the device. RESULTS: Gradients and effective orifice area were respectively 0.9 ± 0.64 mmHg and 3.1 ± 0.7cm2 (pathological) and 3.7 ± 1.1 mmHg and 1.5 ± 0.2cm2 (treated, P < 0.05). Left coronary/non-coronary diameter decreased from 2.4 ± 0.2 cm (pathological) to 2.0 ± 0.2 (treated, P < 0.05). Coaptation length and height were fully restored to basal values following treatment. Visual inspection showed proper dynamics of the leaflet, confirmed by high-speed video and echocardiography. CONCLUSIONS: The device allowed for restoring physiologic-like coaptation in the experimental model, without inducing clinically relevant worsening of the haemodynamics of the treated ARU.