Name: a rabbit aortic valve stenosis model induced by direct balloon injury
Uploaded: 2023-03-31T14:40:00
Description: Watch this Scientific Journal Video about A Rabbit Aortic Valve Stenosis Model Induced by Direct Balloon Injury at JoVE.com

This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. 2020R1A4A3079570), the Ministry of Education (No. 2021R1I1A1A01051425), and the Industrial Strategic Technology Development Program (No. 20014873) funded by the Ministry of Trade, Industry &#38; Energy, Republic of Korea.

All animal research procedures were approved and performed in accordance with the Laboratory Animals Welfare Act, the Guide for the Care and Use of Laboratory Animals, and the Guidelines and Policies for Animal Experiments provided by the Institutional Animal Care and Use Committee (IACUC) at the College of Medicine of The Catholic University of Korea (approval number: CUMC-2021-0176-05). The present study utilized 3 month old male New Zealand white (NZW) rabbits weighing 3.5-4.0 kg, which were maintained under standard ...

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Animal AVS models are commonly used to study the pathological aspects of AVS, including the initiation and progression of AVS. This protocol introduces a new rabbit AVS model induced by a direct balloon injury to the aortic valve. In this study, the aortic valve injury model showed significant leaflet thickening and calcification. Compared to the mild AVS model induced by dietary supplementation, the aortic valve in the direct balloon injury model was selectively injured, leading to thickened cusps and restricted motion,...

It is increasingly recognized that the use of appropriate animal models can contribute to a better understanding of the pathological mechanisms underlying aortic valve stenosis (AVS) due to the lack of access to reliable sources of diseased human aortic valves associated with the progression of aortic stenosis (AS). Among the various animal models for studying AVS, rabbits are one of the most commonly used large-animal AVS models, and the AVS rabbit model is induced either through cholesterol/vitamin D2 supplementation or genetic manipulation1,2,3,4.
Although rabbit AVS models have provided significant insight into the development and progression of AVS, it still remains challenging to induce AVS consistently and reproducibly, as seen in our preliminary experiments.
In addition to diet-induced and genetically susceptible animal models, a new model of AVS has been established through direct mechanical injury in mice5,6. The mechanical injury model successfully induces aortic stenosis and represents a simple and reproducible AVS model in wild-type mice. To the best of our knowledge, there have been no prior studies examining the effects of a mechanical injury on the aortic valve in rabbit models. Thus, this study provides a new procedure for inducing AVS in male New Zealand white rabbits through a direct balloon injury to the aortic valve, which can accurately mimic the condition of valvular aortic stenosis. This protocol includes step-by-step descriptions of the preparation, the surgical procedure, and the post-operative care, which are useful for inducing reproducible AVS rabbit models.

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			<td>3-0 Silk suture</td>
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			<td>4% paraformaldehyde(PFA)</td>
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			<td>Bionet Veterinary monitor</td>
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			<td>C-Arm</td>
			<td>SIEMENS Healthcare GmbH</td>
			<td>Cios alpha</td>
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			<td>Certified Rabbit Diet</td>
			<td>Purina</td>
			<td>5322</td>
			<td>4.7% Hydrogenated Coconut Oil, 0.5% Cholesterol, &#38; 1% Molasse</td>
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			<td>Curadle Smart Incubator</td>
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			<td>CS-CV206</td>
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			<td>Ergocalciferol</td>
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			<td>Fechtner conjunctiva forceps titanium</td>
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			<td>WP1820</td>
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			<td>Shin Poong</td>
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			<td>Glycopyrrolate&#160;</td>
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			<td>Greenflex NS</td>
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			<td>Hematoxylin solution</td>
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			<td>Heparin</td>
			<td>JW pharmaceutical</td>
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			<td>25,000 U</td>
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			<td>Infusion set for single use</td>
			<td>SWOON MEDICAL</td>
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			<td>Iodine</td>
			<td>Green pharmaceutical</td>
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			<td>Iodixanol</td>
			<td>GE Healthcare</td>
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			<td>IV catheter 22 G</td>
			<td>BD&#160;</td>
			<td>382423</td>
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			<td>IV catheter 24 G</td>
			<td>BD</td>
			<td>382412</td>
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			<td>Ketoprofen</td>
			<td>SamChunDang</td>
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			<td>Luer-Lok syringe 10 mL</td>
			<td>Becton Dickinson Medical</td>
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			<td>Luer-Lok syringe 3 mL</td>
			<td>Becton Dickinson Medical</td>
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			<td>Microscope</td>
			<td>OLYMPUS</td>
			<td>SZ61</td>
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			<td>Microtome</td>
			<td>ThermoFisher Scientific</td>
			<td>HM 325</td>
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			<td>MT stain kit</td>
			<td>Sigma-aldrich</td>
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			<td>Needel holder</td>
			<td>Solco</td>
			<td>009-1304</td>
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			<td>Needle Holder with Lock and Suture</td>
			<td>JEUNGDO BIO &#38; PLANT</td>
			<td>H-1222-18</td>
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			<td>Paraffin</td>
			<td>LK LABKOREA</td>
			<td>H06-660-107</td>
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			<td>PBS</td>
			<td>Gibco</td>
			<td>10010-023</td>
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			<td>Potassium chloride 40</td>
			<td>Daihan Pharm</td>
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			<td>KCl</td>
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			<td>Prelude Ideal Hydrophilic Sheath</td>
			<td>MERIT MEDICAL</td>
			<td>PID4F11018SS</td>
			<td>Sheath 4F</td>
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			<td>PTA Balloon Dilatation catheter</td>
			<td>Boston Scientific</td>
			<td>H749-3903280208-0</td>
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			<td>Rompun</td>
			<td>Elanco</td>
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			<td>sterile Gauze</td>
			<td>DAE HAN Medical</td>
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			<td>10 cm x 20 cm&#160;</td>
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			<td>Ansell</td>
			<td>Ansell</td>
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			<td>Surgical Gown</td>
			<td>Yuhan kimberly</td>
			<td>90002-02</td>
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			<td>Surgical Scissors</td>
			<td>Nopa, Germany</td>
			<td>AC020/16</td>
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			<td>Surgical Tape</td>
			<td>3M micopore</td>
			<td>1530-1</td>
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			<td>Syringe 1 mL</td>
			<td>Shin Chang Medical</td>
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			<td>Syringe 10 mL</td>
			<td>Shin Chang Medical</td>
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			<td>Tissue cassette</td>
			<td>Scilav korea</td>
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			<td>Transducer gel&#160;</td>
			<td>SUNGHEUNG</td>
			<td>SH102</td>
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			<td>Tridol</td>
			<td>Yuhan Corp.</td>
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			<td>Tramadol HCl</td>
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			<td>Ultrasound system</td>
			<td>Philps</td>
			<td>Affiniti 50</td>
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			<td>Von Kossa stain kit</td>
			<td>Abcam</td>
			<td>ab105689</td>
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			<td>Zoletil 50</td>
			<td>Virbac korea</td>
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			<td>Tiletamine &#38; zolazepam</td>
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a rabbit aortic valve stenosis model induced by direct balloon injury

Animal models are emerging as an important tool to understand the pathologic mechanisms underlying aortic valve stenosis (AVS) because of the lack of access to reliable sources of diseased human aortic valves. Among the various animal models, AVS rabbit models are one of the most commonly used in large animal studies. However, traditional AVS rabbit models require a long-term period of dietary supplementation and genetic manipulation to induce significant stenosis in the aortic valve, limiting their use in experimental studies. To address these limitations, a new AVS rabbit model is proposed, in which stenosis is induced by a direct balloon injury to the aortic valve. The present protocol describes a successful technique for inducing AVS in New Zealand white (NZW) rabbits, with step-by-step procedures for the preparation, the surgical procedure, and the post-operative care. This simple and reproducible model offers a promising approach for studying the initiation and progression of AVS and provides a valuable tool for investigating the underlying pathological mechanisms of the disease.

Rabbit AVS model induced by aortic valve injury 
To induce the rabbit AVS model, male NZW rabbits weighing 3.5-4.0 kg were used for this study. According to the surgical procedures described in step 2 (Figure 2), the AVS model was established by aortic valve injury, which resulted in mechanical aortic valve degeneration and calcification. The control group included rabbits fed with a 0.5% cholesterol-enriched diet (high-cholesterol, HC) and 50,000 U of vitamin D2 (VitD2...

Watch this Scientific Journal Video about A Rabbit Aortic Valve Stenosis Model Induced by Direct Balloon Injury at JoVE.com

A Rabbit Aortic Valve Stenosis Model Induced by Direct Balloon Injury

An appropriate animal model is needed to understand the pathologic mechanisms underlying aortic valve stenosis (AVS) and to evaluate the efficacy of therapeutic interventions. The present protocol describes a new procedure for developing the AVS rabbit model via a direct balloon injury in vivo.

Animal models are emerging as an important tool to understand the pathologic mechanisms underlying aortic valve stenosis (AVS) because of the lack of ...

Annual models are emerging as an important tool to understand the pathologic mechanisms underlying aortic valve stenosis because of the lack of access to reliable sources of diseased human aortic valves. Traditional aortic valve stenosis rabbit models require long-term dietary supplementation and genetic manipulation to induce significant stenosis in the aortic valve, limiting their use in experimental studies. This technique describes a new procedure for inducing aortic valve stenosis in rabbits through a direct ballon injury to the aortic valve, which can accurately mimic the condition of a human with aortic stenosis.Demonstrating the procedure will be Eun-Hye Park, Jin-Moo Kim, and Eunmi Lee, research specialists from my regulatory. Begin preparing the dilation balloon catheter set by connecting the in deflation device filled with the one-to-one mixture of saline and commercially available contrast medium to the Luer lock part of the balloon catheter. After filling the balloon with an inflation solution, remove the air from the balloon catheter.Begin the surgery procedure by inserting a 24 gauge intravenous or IV catheter into the marginal auricular vein of the anesthetized rabbit. Connect an infusion set with 100 units per kilogram of heparin heparinized saline. Next, connect the rabbit with a multi-parameter veterinary monitor to continuously monitor the vital signs such as the oxygen saturation signal or SpO2 temperature and blood pressure.After placing the rabbit in a supine position on an operating table equipped with a C-arm fluoroscopy, remove the hair from the ventral neck area using animal hair clippers. Sterilize the incision area with iodine and cover the rabbit with surgical towels. To position the rabbit's heart, turn on the C-arm and select the fluoroscopic mode for cardiac imaging.Adjust the rabbit's position to ensure the heart is at the center of the imaging field. Once the position is adjusted, make a longitudinal incision of approximately three centimeter in the skin of the neck and use surgical scissors to cut the fascia and fat tissue. Then carefully separate the muscles until approximately 3 to 3.5 centimeters of the left common carotid artery, or LCCA, is exposed.Ligate the LCCA with a 3-0 silk suture at the top and end of the exposed LCCA to stop the blood flow. Insert a 22 gauge IV catheter into the LCCA. Then introduce a 0.016 inch guide wire into the left ventricle through the IV catheter, ensuring that the tip of the catheter is properly positioned in the imaging field of the C-arm.Next, withdraw the IV catheter, leaving the guide wire before placing a 4 French sheath over the guide wire into the LCCA to introduce the balloon catheter. Carefully insert the eight millimeter balloon catheter over the guide wire into the aortic valve under C-arm fluoroscopic guidance. Place the balloon catheter tip approximately one to two centimeters distal to the aortic valve and inflate the balloon by purging the inflation solution with a pressure inflator at six atmospheres.Next, advance the balloon into the left ventricle or LV apex and pull it back into the LV outlet. Repeat this procedure five times before deflating the balloon. Withdraw the balloon catheter and guide wire, then slowly remove the sheath from the LCCA and immediately tie the LCCA with the suture on the way down to the aortic valve.Clean the incision area with saline to remove the blood clots. Inspect the punctured site for arterial bleeding before closing the muscle and skin with a 3-0 non-absorbable suture. Once done, sterilize the wound using iodine.After the surgery, remove the monitoring patches and clips and keep the rabbit in an intensive care incubator. After eight weeks of the balloon injury, place the anesthetized rabbit on an echo table in the supine position. Apply ultrasound transducer gel to the chest after shaving the chest area.Adjust the transducer to obtain the peristernal long-axis view and the peristernal short-axis view of the aortic valve. Use mode imaging to record images of the aortic valve and save the images for later analysis. The structural change assessment in the aortic valve revealed that eight weeks after the aortic valve injury, the cusps were thickened and the motion was restricted in the injured rabbits fed with the high cholesterol and vitamin D2 diet compared to the control or wild type rabbits, and the rabbits fed the high cholesterol and vitamin D2 diet without valve injury.The rabbits were sacrificed and the hearts were excised eight weeks after the injury for histological analysis of the aortic valve. The aortic valve stained with Masson's trichrome showed increased thickness of the aortic valve cusps in the injured group compared to the control in high cholesterol and vitamin-D2-diet-induced groups. Alizarin Red staining and Von Kossa staining were performed to compare the degree of valvular calcium deposits indicated negligible calcium deposits in the valvular leaflets in the high cholesterol and vitamin-D2-diet induced group.In contrast, significant calcific deposits were observed in the balloon injured group. Successful technique for inducing arctic valve stenosis, in the rabbit model is demonstrated here with a step-by-step explanation of a direct balloon injury to the aortic valve. This simple and reproducible model offers a promising approach for studying the initiation and progression of aortic valve stenosis, and provides a valuable tool for investigating the underlying pathological mechanisms of aortic valve stenosis.

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A Rat Carotid Balloon Injury Model to Test Anti-vascular Remodeling Therapeutics

The rat carotid balloon injury is a well-established surgical model that has been used to study arterial remodeling and vascular cell proliferation. It is also a valuable model system to test, and to evaluate therapeutics and drugs that negate maladaptive remodeling in the vessel. The injury, or barotrauma, in the vessel lumen caused by an inflated balloon via an inserted catheter induces subsequent neointimal growth, often leading to hyperplasia or thickening of the vessel wall that narrows, or obstructs the lumen. The method described here is sufficiently sensitive, and the results can be obtained in relatively short time (2 weeks after the surgery). The efficacy of the drug or therapeutic against the induced-remodeling can be evaluated either by the post-mortem pathological and histomorphological analysis, or by ultrasound sonography in live animals. In addition, this model system has also been used to determine the therapeutic window or the time course of the administered drug. These studies can leadto the development of a better administrative strategy and a better therapeutic outcome. The procedure described here provides a tool for translational studies that bring drug and therapeutic candidates from bench research to clinical applications.

The rat carotid balloon injury model described below allows researchers to evaluate drugs or therapeutics that negate injury-induced arterial hyperplasia. Detailed pre-surgical preparation, surgical procedure, and post-surgical cares of the animal are described.

The rat carotid balloon injury is a well-established surgical model that has been used to study arterial remodeling and vascular cell proliferation. It is ...

Reproducible Arterial Denudation Injury by Infrarenal Abdominal Aortic Clamping in a Murine Model

Percutaneous vascular interventions uniformly result in arterial denudation injuries that subsequently lead to thrombosis and restenosis. These complications can be attributed to impairments in re-endothelialization within the wound margins. Yet, the cellular and molecular mechanisms of re-endothelialization remain to be defined. While several animal models to study re-endothelialization after arterial denudation are available, few are performed in the mouse because of surgical limitations. This undermines the opportunity to exploit transgenic mouse lines and investigate the contribution of specific genes to the process of re-endothelialization. Here, we present a step-by-step protocol for creating a highly reproducible murine model of arterial denudation injury in the infrarenal abdominal aorta using external vascular clamping. Immunocytochemical staining of injured aortas for fibrinogen and &#946;-catenin demonstrate the exposure of a pro-thrombotic surface and the border of intact endothelium, respectively. The method presented here has the advantages of speed, excellent overall survival rate, and relative technical ease, creating a uniquely practical tool for imposing arterial denudation injury in transgenic mouse models. Using this method, investigators may elucidate the mechanisms of re-endothelialization under normal or pathological conditions.

Understanding the cellular and molecular mechanisms of re-endothelialization following arterial denudation injury is of paramount importance in preventing thrombosis and restenosis of arteries. Here we describe a protocol for reproducible arterial denudation injury of the infrarenal abdominal aorta. The procedure was developed to investigate the underlying mechanisms that regulate endothelial regeneration using mouse models.

Percutaneous vascular interventions uniformly result in arterial denudation injuries that subsequently lead to thrombosis and restenosis. These ...

The Rabbit Model of Accelerated Atherosclerosis: A Methodological Perspective of the Iliac Artery Balloon Injury

Acute coronary syndrome resulting from coronary occlusion following atherosclerotic plaque development and rupture is the leading cause of death in the industrialized world. New Zealand White (NZW) rabbits are widely used as an animal model for the study of atherosclerosis. They develop spontaneous lesions when fed with atherogenic diet; however, this requires long time of 4 - 8 months. To further enhance and accelerate atherogenesis, a combination of atherogenic diet and mechanical endothelial injury is often employed. The presented procedure for inducing atherosclerotic plaques in rabbits uses a balloon catheter to disrupt the endothelium in the left iliac artery of NZW rabbits fed with atherogenic diet. Such mechanical damage caused by the balloon catheter induces a chain of inflammatory reactions initiating neointimal lipid accumulation in a time dependent fashion. Atherosclerotic plaque following balloon injury show neointimal thickening with extensive lipid infiltration, high smooth muscle cell content and presence of macrophage derived foam cells. This technique is simple, reproducible and produces plaque of controlled length within the iliac artery. The whole procedure is completed within 20 - 30 min. The procedure is safe with low mortality and also offers high success in obtaining substantial intimal lesions. The procedure of balloon catheter induced arterial injury results in atherosclerosis within two weeks. This model can be used for investigating the disease pathology, diagnostic imaging and to evaluate new therapeutic strategies.

Animal models of atherosclerosis are essential to understand the mechanism and to investigate newer approaches to prevent plaque development or rupture, a leading cause of death in the industrialized world. This protocol uses a combination of balloon injury and cholesterol rich diet to induce atherosclerotic plaques in rabbit iliac artery.

Acute coronary syndrome resulting from coronary occlusion following atherosclerotic plaque development and rupture is the leading cause of death in the ...

Full-root Aortic Valve Replacement by Stentless Aortic Xenografts in Patients with Small Aortic Roots

In patients with small aortic roots who need an aortic valve replacement with biological valve substitutes, the implantation of the stented pericardial valve might not meet the functional needs. The implantation of a too-small stented pericardial valve, leading to an effective orifice area indexed to a body surface area less than 0.85 cm2/m2, is regarded as prosthesis-patient mismatch (PPM). A PPM negatively affects the regression of left ventricular hypertrophy and thus the normalization of left ventricular function and the alleviation of symptoms. Persistent left ventricular hypertrophy is associated with an increased risk of arrhythmias and sudden cardiac death. In the case of predictable PPM, there are three options: 1) accept the PPM resulting from the implantation of a stented pericardial valve when comorbidities of the patient forbid the more technically demanding operative technique of implanting a larger prosthesis, 2) enlarge the aortic root to accommodate a larger stented valve substitute, or 3) implant a stentless biological valve or a homograft. Compared to classical aortic valve replacement with stented pericardial valves, the full-root implantation of stentless aortic xenografts offers the possibility of implanting a 3-4 mm larger valve in a given patient, thus allowing significant reduction in transvalvular gradients. However, a number of cardiac surgeons are reluctant to transform a classical aortic valve replacement with stented pericardial valves into the more technically challenging full-root implantation of stentless aortic xenografts. Given the potential hemodynamic advantages of stentless aortic xenografts, we have adopted full-root implantation to avoid PPM in patients with small aortic roots necessitating an aortic valve replacement. Here, we describe in detail a technique for the full-root implantation of stentless aortic xenografts, with emphasis on the management of the proximal suture line and coronary anastomoses. Limitations of this technique and alternative options are discussed.

Full-root aortic valve replacement by stentless aortic xenograft is a viable option in patients with small aortic roots. We describe, a technique for the full-root implantation of stentless aortic xenografts, with emphasis on the management of the proximal suture line and coronary anastomoses, and discuss its limitations and alternative options.

In patients with small aortic roots who need an aortic valve replacement with biological valve substitutes, the implantation of the stented pericardial ...

Standardized Technique of Aortic Valve Re-implantation for Valve-sparing Aortic Root Replacement

Despite the obvious advantages of the preservation of a normal aortic valve during aortic root replacement, the complexity of valve sparing procedures prevents a number of cardiac surgeons from incorporating them into their practice. The aim of this protocol is to describe a simplified and user-friendly technique of an aortic valve-sparing root replacement (VSRR) procedure by re-implantation of the aortic valve. Proper selection of patients and limitations of the technique are discussed.
In 54 consecutive patients, normal appearing aortic valves were re-implanted in a commercially available polyester prosthesis with pre-shaped sinuses by a simplified and standardized technique. Placement of the first row of the proximal suture line, choice of the prosthesis size, and adjustment of the height of the commissures of the patient to the fixed height of the sinus portion of the prosthesis were slightly modified from the reference techniques with the aim of increasing its feasibility for use by other cardiac surgeons. Early mortality and morbidity as well as 5-year survival, freedom from aortic valve reoperation, and freedom from recurrent moderate regurgitation were collected in all patients.
Thirty-day mortality, re-sternotomy for bleeding, re-sternotomy for mediastinitis, and the incidence of stroke were very low, 1.8% for each (1 of 54). No patient required permanent pace-maker implantation. At 5 years, survival, freedom from aortic valve reoperation, and freedom from recurrent moderate regurgitation were 97.5%, 95.2%, and 91.6%, respectively.
Mid-term results of our standardized technique of re-implantation of the aortic valve for valve-sparing aortic root replacement are very good and compare with more complex techniques reported by experienced surgeons. By following the present protocol of the standardized re-implantation technique, a greater number of cardiac surgeons can perform this procedure with comparable good results.

Valve-sparing aortic root replacement has the advantage of preserving the patient&#39;s own aortic valve. The complexity of the reported techniques to date restricts their use to a limited number of cardiac surgeons. This protocol describes step-by-step a standardized technique reproducible by a greater number of cardiac surgeons.

Despite the obvious advantages of the preservation of a normal aortic valve during aortic root replacement, the complexity of valve sparing procedures ...

A Rabbit Model of Aqueous-Deficient Dry Eye Disease Induced by Concanavalin A Injection into the Lacrimal Glands: Application to Drug Efficacy Studies

Dry eye disease (DED), a multifactorial inflammatory disease of the ocular surface, affects 1 in 6 humans worldwide with staggering implications for quality of life and health care costs. The lack of informative animal models that recapitulate its key features impedes the search for new therapeutic agents for DED. Available DED animal models have limited reproducibility and efficacy. A model is presented here in which DED is induced by injecting the mitogen concanavalin A (Con A) into the orbital lacrimal glands of rabbits. Innovative aspects of this model are the use of ultrasound (US) guidance to ensure optimal and reproducible injection of Con A into the inferior lacrimal gland; injection of Con A into all orbital lacrimal glands that limits compensatory production of tears; and use of periodic repeat injections of Con A that prolong the state of DED at will. DED and its response to test agents are monitored with a panel of parameters that assess tear production, the stability of the tear film, and the status of the corneal and conjunctival mucosa. They include tear osmolarity, tear break-up time, Schirmer&#39;s tear test, rose bengal staining, and tear lactoferrin levels. The induction of DED and the monitoring of its parameters are described in detail. This model is simple, robust, reproducible, and informative. This animal model is suitable for the study of tear physiology and of the pathophysiology of DED as well as for the assessment of the efficacy and safety of candidate agents for the treatment of DED.

This article describes the development of a method to induce acute or chronic dry eye disease in rabbits by injecting concanavalin A to all portions of the orbital lacrimal gland system. This method, superior to those already reported, generates a reproducible, stable model of dry eye suitable for the study of pharmacological agents.

Dry eye disease (DED), a multifactorial inflammatory disease of the ocular surface, affects 1 in 6 humans worldwide with staggering implications for ...

Acute Kidney Injury Model Induced by Cisplatin in Adult Zebrafish

Cisplatin is commonly used as chemotherapy. Although it has positive effects in cancer-treated individuals, cisplatin can easily accumulate in the kidney due to its low molecular weight. Such accumulation causes the death of tubular cells and can induce the development of Acute Kidney Injury (AKI), which is characterized by a quick decrease in kidney function, tissue damage, and immune cells infiltration. If administered in specific doses cisplatin can be a useful tool as an AKI inducer in animal models. The zebrafish has appeared as an interesting model to study renal function, kidney regeneration, and injury, as renal structures conserve functional similarities with mammals. Adult zebrafish injected with cisplatin shows decreased survival, kidney cell death, and increased inflammation markers after 24 h post-injection (hpi). In this model, immune cells infiltration and cell death can be assessed by flow cytometry and TUNEL assay. This protocol describes the procedures to induce AKI in adult zebrafish by intraperitoneal cisplatin injection and subsequently demonstrates how to collect the renal tissue for flow cytometry processing and cell death TUNEL assay. These techniques will be useful to understand the effects of cisplatin as a nephrotoxic agent and will contribute to the expansion of AKI models in adult zebrafish. This model can also be used to study kidney regeneration, in the search for compounds that treat or prevent kidney damage and to study inflammation in AKI. Moreover, the methods used in this protocol will improve the characterization of tissue damage and inflammation, which are therapeutic targets in kidney-associated comorbidities.

This protocol describes the procedures to induce Acute Kidney Injury (AKI) in adult zebrafish using cisplatin as a nephrotoxic agent. We detailed the steps to evaluate the reproducibility of the technique and two techniques to analyze inflammation and cell death in the renal tissue, flow cytometry and TUNEL, respectively.

Cisplatin is commonly used as chemotherapy. Although it has positive effects in cancer-treated individuals, cisplatin can easily accumulate in the kidney ...

A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion

Diverse vascular diseases such as diabetic retinopathy, occlusion of retinal veins or arteries and ocular ischemic syndrome can lead to retinal ischemia. To investigate pathological mechanisms of retinal ischemia, relevant experimental models need to be developed. Anatomically, a main retinal blood supplying vessel is the ophthalmic artery (OpA) and OpA originates from the internal carotid artery of the common carotid artery (CCA). Thus, disruption of CCA could effectively cause retinal ischemia. Here, we established a mouse model of retinal ischemia by transient bilateral common carotid artery occlusion (tBCCAO) to tie the right CCA with 6-0 silk sutures and to occlude the left CCA transiently for 2 seconds via a clamp, and showed that tBCCAO could induce acute retinal ischemia leading to retinal dysfunction. The current method reduces reliance on surgical instruments by only using surgical needles and a clamp, shortens occlusion time to minimize unexpected animal death, which is often seen in mouse models of middle cerebral artery occlusion, and maintains reproducibility of common retinal ischemic findings. The model can be utilized to investigate the pathophysiology of ischemic retinopathies in mice and further can be used for in vivo drug screening.

Here, we describe a mouse model of retinal ischemia by transient bilateral common carotid artery occlusion using simple sutures and a clamp. This model can be useful for understanding the pathological mechanisms of retinal ischemia caused by cardiovascular abnormalities.

Diverse vascular diseases such as diabetic retinopathy, occlusion of retinal veins or arteries and ocular ischemic syndrome can lead to retinal ischemia. ...

The Intra-Aortic Balloon Pump

Cardiogenic shock remains one of the most challenging clinical syndromes in modern medicine. Mechanical support is being increasingly used in the management of cardiogenic shock. Intra-aortic balloon pump (IABP) is one of the earliest and most widely used types of mechanical circulatory support. The device acts by external counterpulsation and uses systolic unloading and diastolic augmentation of aortic pressure to improve hemodynamics. Although IABP provides less hemodynamic support when compared with newer mechanical circulatory support devices, it can still be the mechanical support device of choice in appropriate situations because of its relative simplicity of insertion and removal, need for smaller size vascular access and better safety profile. In this review, we discuss the equipment, procedural and technical aspects, hemodynamic effects, indications, evidence, current status and recent advances in the use of IABP in cardiogenic shock.

We describe the steps for the percutaneous implantation of the intra-aortic balloon pump (IABP), a mechanical circulatory support device. It acts by counterpulsation, inflating at the onset of diastole, augmenting diastolic aortic pressure and improving coronary blood flow and systemic perfusion, and deflating before systole, reducing left ventricular afterload.

Cardiogenic shock remains one of the most challenging clinical syndromes in modern medicine. Mechanical support is being increasingly used in the ...

Drug Treatment by Central Venous Catheter in a Mouse Model of Angiotensin II Induced Abdominal Aortic Aneurysm and Monitoring by 3D Ultrasound

Since pharmaceutical treatment options are lacking in the clinical management of abdominal aortic aneurysm (AAA), animal models, in particular mouse models, are applied to advance the understanding of the disease pathogenesis and to identify potential therapeutic targets. Testing novel drug candidates to block AAA growth in these models generally requires repeated drug administration during the time course of the experiment. Here, we describe a compiled protocol for AAA induction, insertion of an intravenous catheter to facilitate prolonged therapy, and serial AAA monitoring by 3D ultrasound. Aneurysms are induced in apolipoprotein E (ApoE) deficient mice by angiotensin II release over 28 days from osmotic mini-pumps implanted subcutaneously into the mouse back. Subsequently, the surgical procedure for external jugular vein catheterization is conducted to allow for daily intravenous drug treatment or repeated blood sampling via a subcutaneous vascular access button. Despite the two dorsal implants, the monitoring of AAA development is readily facilitated by sequential semi-automated 3D ultrasound analysis, which yields comprehensive information on the expansion of aortic diameter and volume and on aneurysm morphology, as illustrated by experimental examples.

This protocol describes the consecutive implantation of an osmotic pump to induce abdominal aortic aneurysm by angiotensin II release in apolipoprotein E (ApoE) deficient mice and of a vascular access port with a jugular vein catheter for repeated drug treatment. Monitoring of aneurysm development by 3D ultrasound is effectively conducted despite dorsal implants.

Since pharmaceutical treatment options are lacking in the clinical management of abdominal aortic aneurysm (AAA), animal models, in particular mouse ...