This work was supported in part by: Fundaci&#243;n S&#233;neca, Agencia de Ciencia y Tecnolog&#237;a, Regi&#243;n de Murcia, Spain (JT) (Grant number: 11935/PI/09) and the University of Reading, United Kingdom (AG, GB) (Central Funding). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+Imaging+to+Evaluate+Left+Ventricular+Diastolic+Function.">Cardiac Imaging to Evaluate Left Ventricular Diastolic Function.</a> Journal of the American College of Cardiology Cardiovascular Imaging. 8, 1071-1093 (2015).</li></ol>

The authors have nothing to disclose.

We have described a protocol for the echocardiographic examination of cardiac function parameters in the rabbit, representing a large preclinical model1,2,3. The step by step methodology described herein should be considered guidance, which with a complementary study of the basic principles of echocardiography, and a basic knowledge of ultrasound imaging, will help the researcher to obtain, through practice and complementary and...

Longitudinal evaluation of cardiac function in large animal models is a robust research methodology commonly used for the assessment of the effects of novel therapies for treating ischemic and non-ischemic cardiomyopathy. Amongst the several cardiovascular imaging techniques available for preclinical research, echocardiography has been used extensively because of its non-invasive and portable characteristics. In experienced hands, echocardiography is also a very reproducible imaging technique to study cardiac anatomy as well as systolic and diastolic function of the heart.
Large preclinical animal models such as pigs, dogs and rabbits, are paramount for preclinical translational research1,2,3. Indeed, the potential benefit of novel therapies such as cardiac regenerative medicine in the setting of cardiomyopathy requires extensive hypothesis testing in large preclinical models before they can be considered for human use2,4. Compared to other large preclinical models, the rabbit model offers some advantages, including its low maintenance cost, which is comparable to that of mice and rats. However, in contrast to mice and rats, the Ca+2 transport system and cardiac electrophysiology are similar in rabbits as those of humans, and those of other large animal models such as dogs and pigs, thus increasing the translational potential of the rabbit model1,5. Therefore, the rabbit, as a large experimental preclinical model, has an exceptional balance of cost and reproducibility for preclinical translational research.
The rabbit has the additional benefit of its amenability for echocardiographic imaging using clinical ultrasound units routinely used in human and veterinary patients, thus taking advantage of the superiority of harmonic imaging and state-of-the-art technology. For this, sector transducers (also known as phase array) of relatively high frequency (up to 12 MHz), such as those used in neonatal/pediatric cardiology, are preferred. Echocardiographic examination in the rabbit preclinical model allows the complete evaluation of systolic and diastolic function using multiple views and different modes available in modern echocardiographic units (e.g. continuous wave Doppler (CWD), pulsed-wave Doppler (PWD), and Tissue Doppler imaging (TDI)).
Echocardiography is an operator-dependent technique and therefore requires extensive training and core knowledge of the technique in accord with international guidelines. Part of this training can be facilitated with the visualization of videos explaining in detail how different echocardiographic views can be obtained. The achievement of high competency in echocardiographic imaging, as well as development of a standardized protocol and correct technique, are essential to minimize the influence of the operator and to generate reliable quantitative data, as required in rigorous scientific research.
Some considerations are necessary regarding the system and laboratory setup used for echocardiography in rabbits and other large animal models. For a standard transthoracic echocardiographic evaluation of cardiac function, the ultrasound system must include the following modalities: bi-dimensional mode (B-mode or 2D), motion mode (M-mode), color Doppler, as well as CWD, PWD and TDI. Moreover, the machine should have full cardiac analysis and measurement software installed, as well as sufficient internal hard drive space to store enough high quality digital still images and video loops for offline analysis. Some systems use linear array transducers; however, for the best imaging of the heart, phased array sector transducers with a small scan head diameter are preferred, because these allow an easier passage of the ultrasound waves through the narrow intercostal spaces. For rabbits, we use relatively high frequency transducers (up to 12 MHz). The position of the animal for imaging is of utmost importance to acquire good quality images. Thus, both right and left lateral recumbent positions are recommended to obtain all standard imaging planes during an echocardiographic examination. For this, a table with a notch that coincides with the cardiac area of the chest is advisable (Figure 1A). This notched table facilitates the access with the transducer to the area of the chest that will be scanned, and therefore allows free mobility of the hand of the operator whist maintaining the best scanning position of the animal. Positioning the animal in a lateral recumbent position results in a fall of the heart towards the transducer and elevation of the lungs, as well as widening the access window of the ultrasound beam through the intercostal spaces, thus improving overall imaging quality (Figure 1A). The echocardiographic examination should be performed in a blinded fashion and following the guidelines of the Echocardiography Committee of the American College of Veterinary Internal Medicine and the American Society of Echocardiography/European Association for Cardiovascular Imaging6,7,8.
Part of our scientific team is associated with the Cardiology Service of a Veterinary Teaching Hospital that attends daily to veterinary patients (e.g. dogs and cats), for which it has the relevant training and accreditation in veterinary cardiology and echocardiography, and its different imaging modalities, as well as extensive experience in imaging different sizes of animal patients and thoracic conformations with this technique. In addition, we commonly use echocardiography for longitudinal evaluation of cardiac function in a rabbit model of cardiomyopathy induced by anthracyclines9. Here, we describe a step by step echocardiography protocol for evaluation of cardiac function using a clinical ultrasound unit in a large preclinical model such as the rabbit. This protocol is adapted for current international guidelines8, and includes practical recommendations based on our own experiences in clinical and experimental settings.

<table><tbody><tr><td>Bluesensor</td><td>Medicotest</td><td>13BY1062</td><td>Disposable adhesive ECG lectrodes</td></tr><tr><td>Domtor (Medetomidine)</td><td>Esteve</td><td>CN 570686.3</td><td>Veterinary prescription is necessary</td></tr><tr><td>HD11 XE Ultrasound System</td><td>Philips</td><td>10670267</td><td>Echocardiography system.</td></tr><tr><td>Heating Pad</td><td>Solac</td><td>CT8632</td><td></td></tr><tr><td>Imalgene (Ketamine)</td><td>Merial</td><td>RN 9767</td><td>Veterinary prescription is necessary</td></tr><tr><td>Omnifix-F 1 ml syringe</td><td>Braun</td><td>9161406V</td><td></td></tr><tr><td>S12-4</td><td>Philips</td><td>B01YgG</td><td>4-12 MHz phase array transducer</td></tr><tr><td>Ultrasound Transmision Gel (Aquasone)</td><td>Parker laboratories Inc.</td><td>N 01-08</td><td></td></tr></tbody></table>

transthoracic echocardiographic examination in the rabbit model

Large animal models such as the rabbit are valuable for translational preclinical research. Rabbits have a similar cardiac electrophysiology compared to that of humans and that of other large animal models such as dogs and pigs. However, the rabbit model has the additional advantage of lower maintenance costs compared to other large animal models. The longitudinal evaluation of cardiac function using echocardiography, when appropriately implemented, is a useful methodology for preclinical assessment of novel therapies for heart failure with reduced ejection fraction (e.g. cardiac regeneration). The correct use of this non-invasive tool requires the implementation of a standardized examination protocol following international guidelines. Here we describe, step by step, a detailed protocol supervised by veterinary cardiologists for performing echocardiography in the rabbit model, and demonstrate how to correctly obtain the different echocardiographic views and imaging planes, as well as the different imaging modes available in a clinical echocardiography system routinely used in human and veterinary patients.

Parasternal long axis view of the heart
Figure 5A shows an imaging plane of the right PSLAX view where the 4 chambers of the heart are clearly distinguished. You can identify in this view the right ventricle (RV), tricuspid valve (TV), IVS, LV, FW, as well as the mitral valve (MV). When the apex is clearly visible on the left side of the image in this view and the LV is not foreshor...

Watch this Scientific Journal Video about Transthoracic Echocardiographic Examination in the Rabbit Model at JoVE.com

Transthoracic Echocardiographic Examination in the Rabbit Model

Here we describe, step by step, a detailed protocol for performing echocardiography in the rabbit model. We show how to correctly obtain the different echocardiographic views and imaging planes, as well as the different imaging modes available in a clinical echocardiography system routinely used in human and veterinary patients.

Large animal models such as the rabbit are valuable for translational preclinical research. Rabbits have a similar cardiac electrophysiology compared to ...

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12.3K Views.  University of Reading. Here we describe, step by step, a detailed protocol for performing echocardiography in the rabbit model. We show how to correctly obtain the different echocardiographic views and imaging planes, as well as the different imaging modes available in a clinical echocardiography system routinely used in human and veterinary patients.

Video: Transthoracic Echocardiographic Examination in the Rabbit Model

Transthoracic Echocardiography in Mice

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene expression. Transgenic and gene targeting methods can be used to generate mice with altered cardiac size and function,1-3 and as a result, in vivo techniques are needed to evaluate their cardiac phenotype. Transthoracic echocardiography, pulse wave Doppler (PWD), and tissue Doppler imaging (TDI) can be used to provide dimensional measurements of the mouse heart and to quantify the degree of cardiac systolic and diastolic performance. Two-dimensional imaging is used to detect abnormal anatomy or movements of the left ventricle, whereas M-mode echo is used for quantification of cardiac dimensions and contractility.4,5 In addition, PWD is used to quantify localized velocity of turbulent flow,6 whereas TDI is used to measure the velocity of myocardial motion.7 Thus, transthoracic echocardiography offers a comprehensive method for the noninvasive evaluation of cardiac function in mice.

Transthoracic echocardiography offers a noninvasive method for the evaluation of cardiac function in mice. A combination of ultrasound and Doppler imaging modalities can be used to obtain dimensional measurements of the heart and intracardiac blood flow, which together provide an assessment of cardiac systolic and diastolic performance.

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene ...

Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction

Fetal intrauterine growth restriction (IUGR) results in abnormal cardiac function that is apparent antenatally due to advances in fetoplacental Doppler ultrasound and fetal echocardiography. Increasingly, these imaging modalities are being employed clinically to examine cardiac function and assess wellbeing in utero, thereby guiding timing of birth decisions. Here, we used a rabbit model of IUGR that allows analysis of cardiac function in a clinically relevant way. Using isoflurane induced anesthesia, IUGR is surgically created at gestational age day 25 by performing a laparotomy, exposing the bicornuate uterus and then ligating 40-50% of uteroplacental vessels supplying each gestational sac in a single uterine horn. The other horn in the rabbit bicornuate uterus serves as internal control fetuses. Then, after recovery at gestational age day 30 (full term), the same rabbit undergoes examination of fetal cardiac function. Anesthesia is induced with ketamine and xylazine intramuscularly, then maintained by a continuous intravenous infusion of ketamine and xylazine to minimize iatrogenic effects on fetal cardiac function. A repeat laparotomy is performed to expose each gestational sac and a microultrasound examination (VisualSonics VEVO 2100) of fetal cardiac function is performed. Placental insufficiency is evident by a raised pulsatility index or an absent or reversed end diastolic flow of the umbilical artery Doppler waveform. The ductus venosus and middle cerebral artery Doppler is then examined. Fetal echocardiography is performed by recording B mode, M mode and flow velocity waveforms in lateral and apical views. Offline calculations determine standard M-mode cardiac variables, tricuspid and mitral annular plane systolic excursion, speckle tracking and strain analysis, modified myocardial performance index and vascular flow velocity waveforms of interest. This small animal model of IUGR therefore affords examination of in utero cardiac function that is consistent with current clinical practice and is therefore useful in a translational research setting.

We describe examination of fetal cardiac function with contemporary functional fetal echocardiography and fetoplacental Doppler ultrasound using the VisualSonics VEVO 2100 microultrasound in a surgically induced model of intrauterine fetal growth restriction in a rabbit.

Fetal intrauterine growth restriction (IUGR) results in abnormal cardiac function that is apparent antenatally due to advances in fetoplacental Doppler ...

Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, the RV is significantly affected in pulmonary diseases such as pulmonary artery hypertension (PAH). In addition, the RV is remarkably sensitive to cardiac pathologies, including left ventricular (LV) dysfunction, valvular disease or RV infarction4. To understand the role of RV in the pathogenesis of cardiac diseases, a reliable and noninvasive method to access the RV structurally and functionally is essential.
A noninvasive trans-thoracic echocardiography (TTE) based methodology was established and validated for monitoring dynamic changes in RV structure and function in adult mice. To impose RV stress, we employed a surgical model of pulmonary artery constriction (PAC) and measured the RV response over a 7-day period using a high-frequency ultrasound microimaging system. Sham operated mice were used as controls. Images were acquired in lightly anesthetized mice at baseline (before surgery), day 0 (immediately post-surgery), day 3, and day 7 (post-surgery). Data was analyzed offline using software.
Several acoustic windows (B, M, and Color Doppler modes), which can be consistently obtained in mice, allowed for reliable and reproducible measurement of RV structure (including RV wall thickness, end-diastolic&#160;and end-systolic dimensions), and function (fractional area change, fractional shortening, PA peak velocity, and peak pressure gradient) in normal mice and following PAC.
Using this method, the pressure-gradient resulting from PAC was accurately measured in real-time using Color Doppler mode and was comparable to direct pressure measurements performed with a Millar high-fidelity microtip catheter. Taken together, these data demonstrate that RV measurements obtained from various complimentary views using echocardiography are reliable, reproducible and can provide insights regarding RV structure and function. This method will enable a better understanding of the role of RV cardiac dysfunction.

Right ventricle (RV) dysfunction is critical to the pathogenesis of cardiovascular disease, yet limited methodologies are available for its evaluation. Recent advances in ultrasound imaging provide a noninvasive and accurate option for longitudinal RV study. Herein, we detail a step-by-step echocardiographic method using a murine model of RV pressure overload.

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, ...

Assessment of Cardiac Morphological and Functional Changes in Mouse Model of Transverse Aortic Constriction by Echocardiographic Imaging

Transverse aortic constriction (TAC) in mice has been used as a valuable model to study mechanisms of cardiac hypertrophy and heart failure1. A reliable noninvasive method is essential to assess real-time cardiac morphological and functional changes in animal models of heart disease. Transthoracic echocardiography represents an important tool for noninvasive assessment of cardiac structure and function2. Here we used a high-resolution ultrasound imaging system to monitor myocardial remodeling and heart failure progression over time in a mouse model of TAC. B-mode, M-mode, and Doppler imaging were used to precisely assess cardiac hypertrophy, ventricular dilatation, and functional deterioration in mice following TAC. Color and pulse wave (PW) Doppler imaging was used to noninvasively measure pressure gradient across the aortic constriction created by TAC and to assess transmitral blood flow in mice. Thus transthoracic echocardiographic imaging provides comprehensive noninvasive measurements of cardiac dimensions and function in mouse models of heart disease.

The goal of this protocol is to noninvasively assess cardiac structural and functional changes in a mouse model of heart disease created by transverse aortic constriction, using B- and M-mode echocardiography and color/pulse wave Doppler imaging.

Transverse aortic constriction (TAC) in mice has been used as a valuable model to study mechanisms of cardiac hypertrophy and heart failure1. A reliable ...

Percutaneous Contrast Echocardiography-guided Intramyocardial Injection and Cell Delivery in a Large Preclinical Model

Cell and gene therapy are exciting and promising strategies for the purpose of cardiac regeneration in the setting of heart failure with reduced ejection fraction (HFrEF). Before they can be considered for use, and implemented in humans, extensive preclinical studies are required in large animal models to evaluate the safety, efficacy, and fate of the injectate (e.g., stem cells) once delivered into the myocardium. Small rodent models offer advantages (e.g., cost effectiveness, amenability for genetic manipulation); however, given inherent limitations of these models, the findings in these rarely translate into the clinic. Conversely, large animal models such as rabbits, have advantages (e.g., similar cardiac electrophysiology compared to humans and other large animals), whilst retaining a good cost-effective balance. Here, we demonstrate how to perform a percutaneous contrast echocardiography-guided intramyocardial injection (IMI) technique, which is minimally invasive, safe, well tolerated, and very effective in the targeted delivery of injectates, including cells, into several locations within the myocardium of a rabbit model. For the implementation of this technique, we also have taken advantage of a widely available clinical echocardiography system. After putting in practice the protocol described here, a researcher with basic ultrasound knowledge will become competent in the performance of this versatile and minimally invasive technique for routine use in experiments, aimed at hypothesis testing of the capabilities of cardiac regenerative therapeutics in the rabbit model. Once competency is achieved, the whole procedure can be performed within 25 min after anaesthetizing the rabbit.

Novel therapeutic strategies in cardiac regenerative medicine require extensive and detailed studies in large preclinical animal models before they can be considered for use in humans. Here, we demonstrate a percutaneous contrast echocardiography-guided intramyocardial injection technique in rabbits, which is valuable for hypothesis testing the efficacy of such novel therapies.

Cell and gene therapy are exciting and promising strategies for the purpose of cardiac regeneration in the setting of heart failure with reduced ejection ...

Echocardiographic Measurement of Right Ventricular Diastolic Parameters in Mouse

Diastolic dysfunction is a prominent feature of right ventricular (RV) remodeling associated with conditions of pressure overload. However, the RV diastolic function is rarely quantified in experimental studies. This might be due to technical difficulties in the visualization of the RV in the apical four-chamber view in rodents. Here we describe two positions facilitating the visualization of the apical four-chamber view in mice to assess the RV diastolic function.
The apical four-chamber view is enabled by tilting the mouse fixation platform to the left and caudally (LeCa) or to the right and cranially (RiCr). Both positions provide images of comparable quality. The results of the RV diastolic function obtained from two positions are not significantly different. Both positions are comparably easy to perform. This protocol can be incorporated into published protocols and enables detailed investigations of the RV function.

Here we describe and compare two positions for obtaining the apical four-chamber view in mice. These positions enable the quantification of the right ventricular function, provide comparable results, and can be used interchangeably.

Diastolic dysfunction is a prominent feature of right ventricular (RV) remodeling associated with conditions of pressure overload. However, the RV ...

Echocardiographic Assessment of Cardiac Anatomy and Function in Adult Rats

The use of experimental animal models has become crucial in cardiovascular science. Most studies using rodent models are focused on two-dimensional imaging to study the cardiac anatomy of the left ventricle and M-mode echo to assess its dimensions. However, this could limit a comprehensive study. Herein, we describe a protocol that allows an assessment of the heart chamber size, left ventricular function (systolic and diastolic) and valvular function. A conventional medical ultrasound machine was used in this protocol and different echo views were obtained through left parasternal, apical and suprasternal windows. In the left parasternal window, the long and short axis were acquired to analyze left chamber dimensions, right ventricle and pulmonary artery dimensions, and mitral, pulmonary and aortic valve function. The apical window allows the measurement of heart chamber dimensions and evaluation of systolic and diastolic parameters. It also allows Doppler assessment with detection and quantification of heart valve disturbances (regurgitation or stenosis). Different segments and walls of the left ventricle are visualized throughout all views. Finally, the ascending aorta, aortic arch, and descending aorta can be imaged through the suprasternal window. A combination of ultrasound imaging, Doppler flow and tissue Doppler assessment have been obtained to study cardiac morphology and function. This represents an important contribution to improve the assessment of cardiac function in adult rats with impact for research using these animal models.

A non-invasive protocol for transthoracic echocardiography assessment of cardiac anatomy and function for adult rats is presented in the current study. The heart valves, all four cardiac chambers and the ascending aorta, aortic arch and descending aorta are studied in detail.

The use of experimental animal models has become crucial in cardiovascular science. Most studies using rodent models are focused on two-dimensional ...

Transthoracic Echocardiography to Assess Post-Resuscitation Left Ventricular Dysfunction After Acute Myocardial Infarction and Cardiac Arrest in Pigs

One of the main causes of out-of-hospital cardiac arrest is acute myocardial infarction (AMI). After successful resuscitation from cardiac arrest, approximately 70% of patients die before hospital discharge due to post-resuscitation myocardial and cerebral dysfunction. In experimental models, myocardial dysfunction after cardiac arrest, characterized by an impairment in both left ventricular (LV) systolic and diastolic function, has been described as reversible but very little data are available in cardiac arrest models associated with AMI in pigs. Transthoracic echocardiography is the first-line diagnostic test for the assessment of myocardial dysfunction, structural changes and/or AMI extension. In this pig model of ischemic cardiac arrest, echocardiography was done at baseline and 2-4 and 96 hours after resuscitation. In the acute phase, the examinations are done in anesthetized, mechanically ventilated pigs (weight 39.8 &#177; 0.6 kg) and ECG is recorded continuously. Mono- and bi-dimensional, Doppler and tissue Doppler recordings are acquired. Aortic and left atrium diameter, end-systolic and end-diastolic left ventricular wall thicknesses, end-diastolic and end-systolic diameters and shortening fraction (SF) are measured. Apical 2-, 3-, 4-, and 5-chamber views are acquired, LV volumes and ejection fraction are calculated. Segmental wall motion analysis is done to detect the localization and estimate the extent of myocardial infarction. Pulsed Wave Doppler echocardiography is used to record trans-mitral flow velocities from a 4-apical chamber view and trans-aortic flow from a 5-chamber view to calculate LV cardiac output (CO) and stroke volume (SV). Tissue Doppler Imaging (TDI) of LV lateral and septal mitral anulus is recorded (TDI septal and lateral s&#39;, e&#39;, a&#39; velocities). All the recordings and measurements are done according to the recommendations of the American and European Societies of Echocardiography Guidelines.

Transthoracic echocardiography is the first-line diagnostic test for post-resuscitation left ventricular dysfunction and structural changes in a pig model of cardiac arrest.

One of the main causes of out-of-hospital cardiac arrest is acute myocardial infarction (AMI). After successful resuscitation from cardiac arrest, ...

Model of Ischemia and Reperfusion Injury in Rabbits

The protocol here provides a simple, highly replicable methodology to induce in situ acute regional myocardial ischemia in the rabbit for non-survival and survival experiments. New Zealand White adult rabbit is sedated with atropine, acepromazine, butorphanol, and isoflurane. The animal is intubated and placed on mechanical ventilation. An intravenous catheter is inserted into the marginal ear vein for the infusion of medications. The animal is pre-medicated with heparin, lidocaine, and lactated Ringer&#39;s solution. A carotid cut-down is performed to obtain arterial line access for blood pressure monitoring. Select physiologic and mechanical parameters are monitored and recorded by continuous real-time analysis.
With the animal sedated and fully anesthetized, either a fourth intercostal space small left thoracotomy (survival) or midline sternotomy (non-survival) is performed. The pericardium is opened, and the left anterior descending (LAD) artery is located.
A polypropylene suture is passed around the second or third diagonal branch of the LAD artery, and the polypropylene filament is threaded through a small vinyl tube, forming a snare. The animal is subjected to 30 min of regional ischemia, achieved by occluding the LAD by tightening the snare. Myocardial ischemia is confirmed visually by regional cyanosis of the epicardium. Following regional ischemia, the ligature is loosened, and the heart is allowed to re-perfuse.
For both survival and non-survival experiments, the myocardial function can be assessed via an echocardiography (ECHO) measurement of the fractional shortening. For non-survival studies, data from sonomicrometry collected using three digital piezoelectric ultrasonic probes implanted within the ischemic area and the left ventricle developed pressure (LVDP) using an apically inserted left ventricle (LV) catheter can be continuously acquired for evaluating the regional and global myocardial function, respectively.
For survival studies, the incision is closed, a left needle thoracentesis is performed for pleural air evacuation, and postoperative pain control is achieved.

The present study demonstrates a highly reproducible animal model of acute regional myocardial ischemia and reperfusion injury in rabbits using a left mini-thoracotomy for survival cases or a midline sternotomy for non-survival cases.

The protocol here provides a simple, highly replicable methodology to induce in situ acute regional myocardial ischemia in the rabbit for non-survival and ...

Optimizing Pulmonary Artery Banding for Consistent Right Heart Failure Induction

Rat Model of Right-Sided Cardiac Remodeling and Arrhythmia Using Pulmonary Artery Banding

Clinical conditions, including chronic obstructive pulmonary disease or pulmonary arterial hypertension (PAH), can lead to chronic right ventricle pressure overload and progressive right heart failure (RHF). RHF can be identified by right-sided cardiac hypertrophy and dilation associated with abnormal myocardial function affecting the RV and the right atrium (RA). We recently demonstrated that severe RHF is accompanied by an increased risk of atrial inflammation, atrial fibrosis, and atrial fibrillation (AF), the most common type of cardiac arrhythmia (CA). Recent studies have shown that RV and RA inflammation plays an important role in the arrhythmogenesis of CA, including AF. However, the impact of inflammation in the development of CA and AF in RHF is poorly described.
Experimental models of RHF are required to better understand the association between right-sided myocardial inflammation and CA. The rat model of monocrotaline (MCT)-induced pulmonary hypertension (PH) is well-established to provoke RHF. However, MCT triggers severe pneumo-toxicity and pulmonary inflammation. Hence, MCT-induced RHF does not help to distinguish whether the subsequent myocardial inflammation originates from the RHF per se or circulating inflammatory signals secreted by the injured lung.
In this article, a mechanical method involving pulmonary artery trunk banding (PAB) was used to provoke right-sided cardiac arrhythmogenesis. The PAB consists of performing a permanent suture of the pulmonary artery trunk for 3 weeks. Such an approach generates increased right-sided pressure overload. At D21 post-PAB, the suture results in hypertrophied, dilated, and inflamed RV and RA. The PAB-induced RHF is also accompanied by vulnerability to ventricular and atrial arrhythmias, including AF.

Right heart failure (RHF) is characterized by right-sided cardiac dilation and hypertrophy, leading to ventricular and atrial malfunction. Cardiopulmonary conditions associated with RHF are accompanied by an increased risk for cardiac arrhythmias. This article describes a standardized model of pulmonary artery banding-induced RHF associated with enhanced ventricular and atrial arrhythmogenesis.