The in vitro hydrodynamic characteristics of the porcine pulmonary valve and root with regard to the Ross procedure

Эндотелиальные клетки, выстилающие стенки сосудов, преобразовывают деформацию собственных структур, вызванную током крови, в химические сигналы, одним из которых является важный регулятор просвета сосуда - оксид азота (NO). К настоящему моменту накоплен большой объём данных о клеточных механизмах активации продукции NO, однако сведений о динамике генерации оксида азота эндотелиальными клетками в зависимости от гидродинамических условий недостаточно. В этой связи разработка микрофлюидных систем in vitro, имитирующих кровеносное русло, и изучение в них эндотелия в сложных гидродинамических условиях является актуальной задачей. В данной работе для создания контролируемых гидродинамических условий для монослоя эндотелиоцитоподобных клеток EA.hy926 была спроектирована и разработана микрофлюидная система, имитирующая линейные участки микрососудистого русла. Методом непрямого определения содержания оксида азота (II) NO с использованием флуоресцентного зонда 4,5-диаминофлуоресцеина DAF-2 впервые получены данные об увеличении продукции NO клетками EA.hy926 при механическом стрессе, создаваемом потоком ростовой среды. Представлены расчетные гидродинамические характеристики микрофлюидной системы, а также методика измерения продукции NO. Возможность исследования функциональной активности эндотелия позволяет использовать разработанную микрофлюидную модельную систему как для изучения клеточно-автономных регуляторных свойств эндотелия при действии ряда вазоактивных фармакологических препаратов и других методов воздействия на эндотелий, так и при моделируемой дисфункции эндотелия. Endothelial cells lining vascular walls transform the flow-induced deformation of their own structures into chemical signals, one of which, nitric oxide (NO), is an important regulator of the vascular lumen diameter. By present, a large amount of data on cellular mechanisms for activation of NO production has been accumulated. However, there is insufficient information on changes in endothelial NO generation under different hydrodynamic conditions. Therefore, development of microfluidic systems that model blood vessels in vitro and using them to study the endothelium under complex hydrodynamic conditions are relevant tasks. In this study, a microfluidic system was developed to create controlled hydrodynamic conditions for a monolayer of endotheliocyte-like cells EAhy.926. This system simulates linear sections of the microvasculature. By indirect measurement of NO (II) content with a fluorescent 4,5-diaminofluorescein (DAF-2) probe, we showed an increase in the NO production by EAhy.926 cells under mechanical stress generated by the medium flow. The article presents the method for measuring NO production and the calculated hydrodynamic characteristics of the microfluidic system. The results showed that the developed microfluidic model system is promising for studying cell-autonomous regulatory properties of the endothelium both under the action of vasoactive agents and in simulated endothelial dysfunction.

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Does intraoperative transesophageal echocardiography predict pulmonary valve dysfunction during the Ross procedure?

Journal of Cardiothoracic and Vascular Anesthesia ◽

10.1053/jcan.2002.125147 ◽

2002 ◽

Vol 16 (4) ◽

pp. 437-440 ◽

Cited By ~ 3

Author(s):

Carmen B. Gomez ◽

Pablo G. Stutzbach ◽

Eduardo Guevara ◽

Roberto R. Favaloro

Keyword(s):

Transesophageal Echocardiography ◽

Pulmonary Valve ◽

Ross Procedure ◽

Valve Dysfunction ◽

Intraoperative Transesophageal Echocardiography

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Abstract 2866: The Ross-Yacoub Operation For Aneurismal Autograft Roots: A Strategy To Preserve Autologous Pulmonary Valves And Normal Quality Of Life

Circulation ◽

10.1161/circ.118.suppl_18.s_788-b ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Giovanni Battista Luciani ◽

Francesca Viscardi ◽

Mara Pilati ◽

Maria Antonia Prioli ◽

Giuseppe Faggian ◽

...

Keyword(s):

Quality Of Life ◽

Pulmonary Valve ◽

Nyha Class ◽

Root Diameter ◽

Ross Procedure ◽

Cross Sectional ◽

Uncomplicated Pregnancy ◽

Valve Insufficiency ◽

Valve Sparing

Background: Prevalence of autograft dilatation late after the Ross procedure is increasing. To define feasibility and outcome of autograft valve-sparing root reoperation, a 14-year clinical experience was reviewed. Methods: One-hundred-twenty-five late survivors after the Ross procedure (7.0±1.9, 0.5–14 years) had cross-sectional clinical and echocardiographic examination. End-points were freedom from autograft dilatation (Ø>4 cm), from root reoperation, from root replacement and functional outcome after valve-sparing reoperation. Results: Autograft dilatation was found in 33 (26%) patients (freedom of 46±12% at 14 years):12 (10%) patients had aortic aneurysm (>5.0 cm). Age at Ross was 22.6±8.8 years, diagnosis was AI in 9, AS in 1, mixed in 2; 10 had bicuspid aortic valve and 3 prior cardiac operations. All, but one (cylinder inclusion), had undergone root technique. Risk factors for root reoperation were younger age (p=0.04), prior operation (p=0.01), root technique (p=0.001). Nine of 12 had reoperation for aneurysm at 7.8±1.8 years after the Ross procedure, 3 are scheduled. During this study, 2 additional patients underwent root reoperation 12.6 years after Ross procedure done abroad. Two patients had root replacement and 9 (82%) remodelling with autograft-valve preservation (7 Yacoub, 2 sinotubular junction/ascending aorta): all survived. Severe AI, but not root diameter, was associated with failure to preserve the valve (p=0.015). Fourteen-year freedom from root reoperation was 80±8% and from full root replacement 96±3%. Up to 6 years (mean 3.1±1.5) after reoperation, all pts are in NYHA class I and medication-free: 8/9 patients have mild AI or less, while 1 required valve replacement 51 months after remodeling. One patient carried out an uncomplicated pregnancy 3 years after Ross-Yacoub operation. Conclusions: Root reoperation with pulmonary valve preservation is feasible in most patients with autograft aneurysm, allowing for maintenance of normal quality of life. Referral of patients with dilated root for surgery prior to onset of severe valve insufficiency increases likelihood of pulmonary valve-sparing. Mid-term functional behaviour of remodelled autograft roots is rewarding, however continued observation is warranted.

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Preclinical study of a self-expanding pulmonary valve for the treatment of pulmonary valve disease

Regenerative Biomaterials ◽

10.1093/rb/rbaa035 ◽

2020 ◽

Vol 7 (6) ◽

pp. 609-618

Author(s):

Dajun Kuang ◽

Yang Lei ◽

Li Yang ◽

Yunbing Wang

Keyword(s):

Pulmonary Artery ◽

Pulmonary Valve ◽

Control Valve ◽

Calcium Content ◽

Structure Design ◽

In Vitro Tests ◽

Valvular Regurgitation ◽

Application Range ◽

Support Frame

Abstract In the past decade, balloon-expandable percutaneous pulmonary valves have been developed and applied in clinical practice. However, all the existing products of pulmonary artery interventional valves in the market have a straight structure design, and they require a preset support frame and balloon expansion. This shape design of the valve limits the application range. In addition, the age of the population with pulmonary artery disease is generally low, and the existing products cannot meet the needs of anti-calcification properties and valve material durability. In this study, through optimization of the support frame and leaflet design, a self-expanding pulmonary valve product with a double bell-shaped frame was designed to improve the match of the valve and the implantation site. A loading and deployment study showed that the biomaterial of the valve was not damaged after being compressed. Pulsatile flow and fatigue in vitro tests showed that the fabricated pulmonary valve met the hydrodynamic requirements after 2 × 108 accelerated fatigue cycles. The safety and efficacy of the pulmonary valve product were demonstrated in studies of pulmonary valve implantation in 11 pigs. Angiography and echocardiography showed that the pulmonary valves were implanted in a good position, and they had normal closure and acceptable valvular regurgitation. The 180 days’ implantation results showed that the calcium content was 0.31–1.39 mg/g in the anti-calcification treatment group, which was significantly lower than that in the control valve without anti-calcification treatment (16.69 mg/g). Our new interventional pulmonary valve product was ready for clinical trials and product registration.

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Infective Endocarditis 2 Decades After Pulmonary Autograft Ross Procedure

Journal of Investigative Medicine High Impact Case Reports ◽

10.1177/2324709620940490 ◽

2020 ◽

Vol 8 ◽

pp. 232470962094049

Author(s):

Robin Boyer ◽

Charnpreet Upple ◽

Fowrooz Joolhar ◽

Greti Petersen ◽

Arash Heidari

Keyword(s):

Infective Endocarditis ◽

Pulmonary Valve ◽

Right Ventricular Outflow Tract ◽

Ventricular Outflow Tract ◽

Ross Procedure ◽

Pulmonary Autograft ◽

Echocardiographic Examination ◽

Valve Reconstruction ◽

The Right ◽

Pulmonary Homograft

Pulmonary autograft, or Ross procedure, is performed by supplanting a diseased aortic valve with the patient’s own pulmonary valve. Reconstruction of the right ventricular outflow tract is then completed using a pulmonary homograft. To our knowledge, infective endocarditis occurring decades after the Ross procedure has not been reported. Diligent echocardiographic examination can be crucial to ensure prompt treatment and avoid the 25% mortality rate associated with infective endocarditis. Clinical suspicion should remain high in those with a pulmonary autograft history. In this article, we report the case of a 39-year-old patient with infective endocarditis presenting 22 years after Ross procedure.

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In-vitro and in-vivo evaluation of a novel bioprosthetic pulmonary valve for use in congenital heart surgery

Journal of Cardiothoracic Surgery ◽

10.1186/s13019-019-0830-1 ◽

2019 ◽

Vol 14 (1) ◽

Author(s):

Jonas Rasmussen ◽

Søren Nielsen Skov ◽

Ditte Bruus Nielsen ◽

Ida Lindhardt Jensen ◽

Marcell Juan Tjørnild ◽

...

Keyword(s):

Congenital Heart ◽

Heart Surgery ◽

Pulmonary Valve ◽

Congenital Heart Surgery ◽

In Vivo Evaluation

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Ross Procedure: How to Do It and How to Teach It

World Journal for Pediatric and Congenital Heart Surgery ◽

10.1177/2150135119852324 ◽

2019 ◽

Vol 10 (5) ◽

pp. 624-627

Author(s):

Jeremy L. Herrmann ◽

Amanda R. Stram ◽

John W. Brown

Keyword(s):

Aortic Valve ◽

Aortic Stenosis ◽

Aortic Valve Replacement ◽

Valve Replacement ◽

Prosthetic Valve ◽

Pulmonary Valve ◽

Prosthetic Graft ◽

Ascending Aorta ◽

Ross Procedure

Prosthesis choice for aortic valve replacement (AVR) in children is frequently compromised by unavailability of prostheses in very small sizes, the lack of prosthetic valve growth, and risks associated with long-term anticoagulation. The Ross procedure with pulmonary valve autograft offers several advantages for pediatric and adult patients. We describe our current Ross AVR technique including replacement of the ascending aorta with a prosthetic graft. The procedure shown in the video involves an adult-sized male with a bicuspid aortic valve, mixed aortic stenosis and insufficiency, and a dilated ascending aorta.

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