Systematic adjustment of root dimensions to cusp size in aortic valve repair: a computer simulation

OBJECTIVES

Aortic valve repair requires the creation of a normal geometry of cusps and aortic root. Of the different dimensions, geometric cusp height is the most difficult to change while annular and sinotubular dimensions can be easily modified. The objective of this study was to investigate, by computer simulation, ideal combinations of annular and sinotubular junction size for a given geometric height.

METHODS

Based on a literature review of anatomical data, a computational biomechanics model was generated for a tricuspid aortic valve. We aimed to determine the ideal relationships for the root dimensions, keeping geometric height constant and creating different combinations of the annular and sinotubular junction dimensions. Using this model, 125 virtual anatomies were created, with 25 different combinations of annulus and sinotubular junction. Effective height, coaptation height and mechanical cusp stress were calculated with the valves in closed configuration.

RESULTS

Generally, within the analysed range of geometric heights, changes to the annular diameter yielded a stronger impact than sinotubular junction diameter changes for optimal valve configuration. The best results were obtained with the sinotubular junction being 2-4 mm larger than the annulus, leading to higher effective height, normal coaptation height and lower stress. Within the range tested, stenosis did not occur due to annular reduction.

CONCLUSIONS

In tricuspid aortic valves, the geometric height can be used to predict ideal post-repair annular and sinotubular junction dimensions for optimal valve configuration. Such an ideal configuration is associated with reduced cusp stress.

Aortic Valve Replacement: Understanding Predictors for the Optimal Ministernotomy Approach

INTRODUCTION

The most common minimally invasive approach for aortic valve replacement (AVR) is the partial upper mini-sternotomy. The aim of this study is to understand which preoperative computed tomography (CT) features are predictive of longer operations in terms of cardio-pulmonary bypass timesand cross-clamp times.

METHODS

From 2011 to 2022, we retrospectively selected 246 patients which underwent isolated AVR and had a preoperative ECG-gated CT scan. On these patients, we analysed the baseline anthropometric characteristics and the following CT scan parameters: aortic annular dimensions, valve calcium score, ascending aorta length, ascending aorta inclination and aorta-sternum distance.

RESULTS

We identified augmented body surface area (>1.9 m2), augmented annular diameter (>23 mm), high calcium score (>2500 Agatson score) and increased aorta-sternum distance (>30 mm) as independent predictors of elongated operation times (more than two-fold).

CONCLUSIONS

Identifying the preoperative predictive factors of longer operations can help surgeons select cases suitable for minimally invasive approaches, especially in a teaching context.

Twenty-year experience of aortic valve reimplantation using the Valsalva graft

OBJECTIVES

Over the past 20 years, valve-sparing aortic root replacement has aroused increasing interest because of a progressive attitude towards the preservation of natural tissue. Aortic reimplantation is the most used technique to spare the valve, allowing simultaneously aortic root replacement and aortic annular stabilization. The reimplantation into a graft with sinuses guarantees an optimal anatomic and functional reconstruction with established good results at 15 years. The aim of this study is to report the world longest follow-up (up to 20 years) of aortic valve reimplantation using the Valsalva graft.

METHODS

From February 2000 to December 2021, 265 consecutive patients with aortic root aneurysm received aortic valve reimplantation using the Valsalva graft. From 2018, leaflet plication with the routine use of calliper was performed. For each patient, we performed both intraoperative and post-procedural transoesophageal echocardiography. All patients were followed with clinical assessment and echocardiography. The mean duration of follow-up was 85 ± 63 months.

RESULTS

The study cohort had a median age of 55 ± 18 and 87.2% were male. The aortic root aneurysm was associated to bicuspid aortic valve in 18.9% of patients and to Marfan syndrome in 10.6% of cases. 55.9% had an aortic regurgitation ≥ 2+. Overall survival at 15 was 87.6 ± 3.4. Freedom from cardiac death was stable at 99.6 ± 0.4 at 5, 10 and 15 years. Freedom from recurrent AR ≥3+ and freedom from reoperation remained stable at 10 and 15 years at 92.2 ± 2.1 and 95.9 ± 1.6, respectively. There was a minimal incidence of infective endocarditis (0.8%), thromboembolism (2.2%) and haemorrhage (2.0%). Six out of 7 patients requiring reoperation had surgery in the first period of our experience (last in 2004). Early suboptimal results had a negative effect on residual aortic regurgitation. Moreover, we hypothesized that the routine use of calliper may have contributed to a further improvement of the outcome, even if these data need to be confirmed by a longer follow-up.

CONCLUSIONS

The first long-term follow-up after aortic valve reimplantation using the Valsalva graft demonstrated excellent results. These long-term results gradually improved with learning curve, remaining stable during the second decade of observation. The systematic use of calliper may have contributed to a further improvement of the outcome.

Mitral repair of myxomatous valves with simple annuloplasty: a follow-up up to 12 years

OBJECTIVES

Diffuse myxomatous mitral valve degeneration (DMD) represents a challenge in the reparative mitral valve surgery. A subgroup of patients with symmetrical DMD can be effectively treated with a simple band-annuloplasty with good early and mid-term results. Here, we evaluate the long-term outcomes in terms of freedom from reoperation, recurrence of moderate or severe mitral regurgitation (MR) and overall survival.

METHODS

Between April 2006 and December 2020, patients with DMD causing severe MR and the echocardiographic features of symmetrical bileaflet prolapse, central regurgitant jet(s), annular dilation and no chordal ruptures were treated using a simple annuloplasty with a semi-rigid band. These patients were prospectively collected and retrospectively analysed.

RESULTS

Seventy-five patients were enrolled. The mean clinical follow-up time was 104 [standard deviation (SD): 43] months, and echocardiographic follow-up time was 95 (SD: 43) months. The mean age was 54 (SD: 15) years, and 56% were females. Long-term overall survival was 98.2% [standard error (SE): 1.8], 93.7% (SE: 4.7) and 93.7% (SE: 4.7) at 4, 8 and 12 years, respectively. The freedom from reoperation was 100% at 4 and 8 years and 94.1% (SE: 5.7) at 12 years. The freedom from recurrent moderate or severe MR was 98.3% (SE: 1.7), 98.3% (SE: 1.7) and 92.8% (SE: 5.5) at 4, 8 and 12 years, respectively.

CONCLUSIONS

Mitral repair with the simple band-annuloplasty for the treatment of MR due to symmetrical DMD seems to be stable and effective in the long term.

Reimplantation versus aortic ring annuloplasty in bicuspid valve with borderline aortic root ectasia

Objective

Methods

Results

Conclusions

Root Reimplantation and Aortic Annuloplasty With External Ring in Bicuspid Aortic Valve: An Anatomical Comparison

Aortic annuloplasty has demonstrated to be a protective factor in valve-sparing root replacement and aortic valve repair. Both reimplantation for aortic root aneurysms and external ring annuloplasty for isolated aortic regurgitation have demonstrated good long-term results. The aim of this anatomical study is to compare aortic reimplantation with Valsalva graft with aortic external ring annuloplasty in bicuspid aortic valves, analyzing their morphological features with CT scan. We selected 56 patients with bicuspid aortic valve who underwent reimplantation procedure with Valsalva graft or external ring annuloplasty; after propensity-matching, 2 homogeneous groups of 10 patients each were obtained. Through multiplanar ECG-gated CT-Scan reconstructions, pre- and postoperative, aortic annular, and valve geometrical characteristics were compared (diameters, perimeter, area and ellipticity index for the annulus; effective height, coaptation length and commissural height for the valve). Aortic root volume was also analyzed. Postoperative comparison of the two groups showed similar geometric features of the aortic annulus in terms of major and minor diameters, perimeter, area and ellipticity index. Analysis of valve's parameters showed similar results in terms of effective height and coaptation length (respectively 10.9 ± 2.1 mm and 7.5 ± 1.9 mm in External Ring group and 10.1 ± 2.0 mm and 7.6 ± 1.6 mm in the Reimplantation group). Both techniques achieve an efficient annuloplasty with similar anatomical results on bicuspid the aortic valves. The stability of these results needs to be confirmed by long-term clinical and echocardiographic follow-up.

Optimized use of the "skirt" of the Valsalva graft for the completion Bentall

We report the case of a patient with an aortic root aneurysm who had previously undergone aortic valve replacement with a large mechanical prosthesis which proved to be normally functioning at the time of reoperation. We describe a new technique of replacing the aortic root while retaining the existing aortic valve similar to the "completion Bentall" procedure using a 32 mm Valsalva graft by suturing the skirted portion of the graft to the sewing ring of the mechanical valve. The ability of the skirt to increase its diameter was the key of this approach.

External Stents for Vein Grafts in Coronary Artery Bypass Grafting: Targeting Intimal Hyperplasia

INTRODUCTION

Progressive saphenous vein graft (SVG) failure remains a key limitation to the long-term success of coronary artery bypass grafting (CABG). SVG disease after the first year is dominated by intimal hyperplasia, which predisposes the SVG to thrombosis and accelerated atherosclerosis. The objective of this study was to review and summarize the latest experimental and clinical data on the use of mechanical external stents for vein grafts.

METHODS

In January 2020, the PubMed database was searched using the terms "external stent", "CABG", "saphenous vein graft" and "intimal hyperplasia". The results were reviewed and only randomized experimental and clinical studies that analyzed the effect of external stenting on venous intimal hyperplasia were included in the analysis, together with studies that investigated the clinical benefit of external stenting.

RESULTS

Eight experimental and four clinical trials met the search criteria. Controlled trials in different large animal models concluded that external stenting significantly reduced intimal hyperplasia 3-6 months post implantation, and reduced both thrombosis rates and the development of lumen irregularities. Data from randomized controlled trials with a follow-up period of 1-4.5 years supported the pre-clinical findings and demonstrated that external stents significantly reduced vein graft disease.

CONCLUSION

Strong evidence indicates that supporting the vein with external stents is safe and leads to clear advantages at both the anatomical and cellular levels. With the further accumulation of consistent positive results, external stenting of SVG may become the standard of care in future CABG.

Long-term follow-up of Bentall procedure using the Perimount bioprosthesis and the Valsalva graft

OBJECTIVES

Bentall procedure is the gold standard for aortic root pathologies when valve repair is not feasible. The development of durable bioprosthetic valves and improved vascular conduits allowed the implementation of bioprosthetic composite grafts; hereby, we performed a retrospective analysis of long-term follow-up of Bentall procedure using the Valsalva graft and the Perimount Magna Ease prosthesis.

METHODS

From June 2000 to March 2019, 309 patients received an aortic root and valve replacement with a bioprosthetic composite graft. The mean age was 69 ± 6.9 years, and the majority were men (88%); most of them were affected by aortic stenosis (86%) and the mean aortic root diameter was 48.6 ± 5.5 mm.

RESULTS

Freedom from cardiac death was 76.8% [confidence interval (CI) 32.5-94.0] at 16 years. Freedom from thromboembolism, haemorrhage, structural valve deterioration and infective endocarditis was 98.2% (CI 96.0-98.9), 95.2% (CI 87.1-98.2), 87.5% (CI 63.2-97.1) and 79.6% (CI 45.3-95.6) at 16 years, respectively. Freedom from reoperation was 74.7% (CI 41.9-90.6).

CONCLUSIONS

These data indicate that, in experienced centres, the Bentall procedure is a safe and effective intervention. This is the first long-term follow-up that analyses the results after implantation of a composite graft made with the Perimount Magna Ease aortic valve and the Valsalva graft.

Ascending aorta disruption after thoracic blunt trauma

Blunt traumatic aortic injury is the second leading cause of death after motor vehicle accidents. The most frequent localisation of aortic lesion is the isthmus, especially in those who survived the accident. Here we report a case of blunt traumatic aortic injury with unusual localisation and modality. A 31 years old man sustained a motorcycle accident, being run over by a car. Computed tomography scan showed an atypical ascending aorta lesion, confirmed by intraoperative finding. The patient underwent emergency ascending aorta replacement with Dacron tubular graft. The patient was discharged uneventfully on 35th postoperative day, after multiple maxillofacial surgeries for concomitant injuries.

Open and endovascular treatment by covered and multilayer stents in the therapy of renal artery aneurysms: mid and long term outcomes in a single center experience

AIM

The purpose of this paper is to evaluate the mid and long terms outcomes of open and endovascular surgical treatment, as well as multilayer stent, in patients affected by Renal Artery Aneurysm (RAA).

PATIENTS AND METHODS

Twenty five patients with RAA (24 monolateral and 1 bilateral aneurysm, 26 aneurysms) were observed between 2000 and 2015: 4 were not treated due to the small size of the aneurysm (< 2.5 cm); out of the remaining, 16 underwent endovascular treatment, 2 were treated by open surgery consisting in aneurysmectomy and graft reconstruction and 5 (in 1 patient bilateral) were treated by ex vivo repair and autotransplantation.

RESULTS

Out of the 22 patients treated for RAA, one patient operated upon open surgery presented an early thrombosis of a PTFE graft, followed by nephrectomy (4.7%); one patient underwent autotransplantation showed an ureteral kinking without functional consequences. In a follow-up ranging from 1 and 11 years (mean 5 years), no deaths were observed; all the renal arteries repaired were patents and 16 out of 21 patients had a significative reduction of systemic blood pressure.

DISCUSSION

The choice of the best treatment is based on aneurysm's morphology according to Rundback's classification. The type I, involving the main renal artery, is always treated by endovascular approach; type II, involving renal artery bifurcations may be treated by open surgery or multilayer stents; type III (hilar or intraparenchymal aneurysms) needs only an open surgical treatment as autotransplantation.

CONCLUSION

Based on our experience it seems that most of RAAs may be treated by endovascular technique. The ex vivo autotransplantation represents the first-line treatment in hilar and intraparenchymal aneurysms. Multilayer stents seem to have good outcome in the treatment of aneurysms involving arterial bifurcations. Mid and long term results, related to kidney preservation and to normalization of blood pressure, seems satisfying.

Mid- and long-term results of endovascular treatment in thoracic aorta blunt trauma

Study Aim. Evaluation of results in blunt injury of the thoracic aorta (BAI) endovascular treatment. Materials and Methods. Sixteen patients were treated for BAI. Thirteen patients had associated polytrauma, 4 of these had a serious hypotensive status and 4 had an hemothorax. In the remaining 3, two had a post-traumatic false aneurysm of the isthmus and 1 had a segmental dissection. In those 13 patients a periaortic hematoma was associated to hemothorax in 4. All patients were submitted to an endovascular treatment, in two cases the subclavian artery ostium was intentionally covered. Results. One patient died for disseminated intravascular coagulation. No paraplegia was recorded. No ischemic complications were observed. A type I endoleak was treated by an adjunctive cuff. During the followup (1–9 years) 3 patients were lost. A good patency and no endoleaks were observed in all cases. One infolding and 1 migration of the endografts were corrected by an adjunctive cuff. Conclusion. The medium and long term results of the endovascular treatment of BAI are encouraging with a low incidence rate of mortality and complications. More suitable endo-suite and endografts could be a crucial point for the further improvement of these results.