Name: Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation (Video) | JoVE Journal
Uploaded: 2021-09-24T15:00:00.000+00:00
Duration: 8 min 56 s
Description: Learn sterile pericarditis techniques in Aachener minipigs to model atrial myopathy and atrial fibrillation. This method enables rapid disease induction and repeated electrophysiology studies for pre-clinical research.

ai_agent_IP

ai_agent

maintenance

instantTrialDurationMinutes

isBiopharma

enableNewMyJoveSectionDesign

educationFeatures

seoMetaApi

ai_copilot_institution_blacklist

ai_chat_institution_blacklist

freeAccessWindow

ssoRoleCapture

scheduledMaintenanceBanner

joveLabsFeatures

disable_autoplay_for_bots

extended_trial_duration

5 minutes

This work was supported by an Industrieel OnderzoeksFonds/Strategisch Basisonderzoek (IOF/SBO) research grant (PID34923) and a Geconcerteerde Onderzoeksactie (GOA) grant (PID36444) of the University of Antwerp; by a Senior Clinical Investigator fellowship (to VFS) and research grants of the Fund for Scientific Research Flanders (Application numbers 1842219N, G021019N, G0D0520N, and G021420N); by a research grant of ERA.Net RUS Plus (2018, Project Consortium 278); by a Vlaamse Interuniversitaire Raad/Interuniversitair Bijzonder OnderzoeksFonds (VLIR/iBOF) grant (20-VLIR-iBOF-027). We thank the firms Abbott and Boston Scientific for sponsoring a large part of the pacemaker leads and the firms, Medtronic and Biotronik, for the loan of a pacemaker programmer. We thank the animal staff of the University of Antwerp animal facility for their excellent care of the animals.

This protocol has been approved by the University of Antwerp Ethical Committee for Animal Testing (case number 2019-29) and follows the animal care guidelines of the University of Antwerp. Seventeen 6-month-old Aachener minipigs (male, castrated) weighing ~20 kg were selected for this study.
1. Medication and anesthesia
<ol>
	<li>Premedication
	<ol>
		<li>Ensure that the pigs are fasted for 12 h, but with unlimited access to water.</li>
		<li>For sedation, administer the following in one intramuscular injection: atropine 0.05 mg/kg, ketamine 10 mg/kg, midazolam 0.5 mg/kg.</li>
		<li>Determine the exact weight of the pig after it has lost consciousness (approximately 10 min post dose). Transport the pig to the operating theater.</li>
		<li>Place the pig on a heating pad.</li>
		<li>Apply ECG monitoring, pulse oximeter, and perform an initial thermometry.</li>
		<li>Insert an over-the-needle catheter (22 G) into the marginal ear vein or the external saphenous vein.</li>
	</ol>
	</li>
	<li>Anesthesia
	<ol>
		<li>For the induction of anesthesia, administer a bolus of propofol (1-4 mg/kg IV) before starting intubation. If superficial anesthesia is noted, administer an extra bolus of midazolam 0.2 mg/kg IV, and proceed to the intubation after ~5 min.</li>
		<li>Intubation
		<ol>
			<li>Place the pig in prone position.</li>
			<li>Ask an assistant to hold the mouth of the animal open using two slings of gauze and/or a mouth spreader. Spray 1 mL (10 mg) of lidocaine in the larynx with a 2 mL needleless syringe, wait for 30-60 s to desensitize the larynx, and then continue.</li>
			<li>Place an endotracheal tube (ETT) with an internal diameter of 6.5 mm using a laryngoscope. Use a laryngoscope to visualize, displace the epiglottis from the soft palate, and place a stylet into the ETT for better manipulation. 
			NOTE: The pig&#39;s mouth cannot be opened widely, and the distance from the nose tip to the larynx is long. Therefore, visualization of the rima glottis is limited. Hence, the ETT and the stylet help visualization.</li>
		</ol>
		</li>
		<li>When connecting the ventilator, give supplementary medication if needed: midazolam 0.5 mg/kg IV and/or alfentanil 30 &#181;g/kg IV.</li>
		<li>Use the following ventilator settings: volume control ventilation (VCV) with a pre-set tidal volume of 10 mL/kg, leading towards a peak inspiratory pressure (PIP) of 11-15 cmH20, a positive end-expiratory pressure PEEP of 2-5 cmH20; respiratory rate: 12-16 Brpm to maintain end-tidal CO2 (ETCO2) between 35-45 mmHg; FiO2: 50% (to be reduced when saturation is 100%); sevoflurane 2.5%.</li>
		<li>For analgesia, use alfentanil 0.5-1 &#181;g&#183;(kg&#183;min)-1 CRI.</li>
		<li>Administer a bolus of 10 mL/kg of plasmalyte 3-5 mL&#183;(kg&#183;h)-1 over 10-20 min to correct hypotension due to hypovolemia.</li>
		<li>Administer 1 g of cefazoline IV. For every 2 h of surgery, administer an extra 500 mg of cefazoline IV. 
		NOTE: For an overview of the emergency medication to have at hand in the operating theater, see Table 1. Urinary bladder catheterization is difficult in male pigs and, in general, not necessary for this procedure.</li>
		<li>Shave the thoracic and neck region of the animal.</li>
		<li>Apply vet ointment to the eyes to prevent dryness and eye irritation during anesthesia.</li>
		<li>Continuously monitor the vital parameters. Check the depth of anesthesia at least every 10 min by assessing whether the jaw tonus is relaxed, the palpebral reflex is absent, the eyes are rotated, and there are no behavioral signs of excitation. Check the color of the mucosa and capillary refill time to evaluate tissue perfusion. Record all data, together with all administered medication, in an individual anesthetic chart.</li>
		<li>Arterial line placement
		<ol>
			<li>Prepare the pressure conducting system. Add 5000 IU of heparin to an IV bag of 500 mL of 0.9% NaCl.</li>
			<li>Return the animal to supine position. Extend the leg and locate the femoral artery using ultrasound with the vascular probe in carotid setting. Disinfect the inguinal zone with chlorhexidine.&#160;Use umonium for sterilization of the ultrasound probe (or use a sterile transducer cover) and use sterile gloves to assure antiseptic technique.</li>
			<li>Puncture the femoral artery using ultrasound guidance. Insert a 3 Fr sheath using the Seldinger technique. 
			NOTE: Because of the small diameter of the femoral artery, it can be helpful to let an assistant insert the guide wire through the needle. Just the action of lifting the ultrasound probe may dislocate the needle tip.</li>
			<li>Fixate the sheath with a suture. Connect the sheath to the transducer and flush. Monitor the arterial blood pressure in real time.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
2. Surgery
<ol>
	<li>Preparation
	<ol>
		<li>Ensure that the animal is supine in a stable position. For extra stability, place prewarmed IV bags in a paraspinal position to support the animal.</li>
		<li>Place the earthing plate of the electrocautery underneath the animal. Use a small amount of ultrasound gel to ensure proper contact with the skin.</li>
		<li>Skin preparation: shave the animal in the following regions: neck, upper limbs, anterior thorax, upper part of the abdomen, inguinal and ECG electrode sites. Perform three alternating scrubs with alcohol 70% and iodine 2% to properly disinfect the skin.</li>
		<li>Place sterile drapes. Wrap the claws of the animal in sterile sheets or gloves as well. Use sterile gauze to retract them.</li>
		<li>To ensure sterile conditions, drape the surgical area with sterile surgical covers, use sterile instruments, and work under sterile conditions until skin closure. 
		NOTE: Throughout the procedure, surgeons must wear a hair cap, a mouth mask, a surgical gown, and sterile gloves.</li>
	</ol>
	</li>
	<li>Surgical placement of a permanent central venous catheter (CVC)
	<ol>
		<li>Make a 5 cm incision in the groove at the medial border of the sternocleidomastoid muscle. Bluntly dissect until the internal jugular vein is reached.</li>
		<li>Remove fibrous tissue around the vein and place a squared suture (= &#160;3 to 4 stitches forming a circle) with Prolene 6-0 around the desired catheterization site to gain vessel control.</li>
		<li>Cannulate the internal jugular vein with a 3 French triple-lumen CVC using the Seldinger technique. Tighten the Prolene 6-0 suture around the catheter.</li>
		<li>Fixate the handle of the catheter to the sternocleidomastoid muscle.</li>
		<li>Tunnel the three catheter lumina separately: use a large pair of blunt dissecting scissors to create the tunnel and an atraumatic clamp pull the catheter lumina through the tunnel. &#160;Attach the ends of the catheter firmly to the skin andput on the needle-free injection port. The exit sites of the catheter lumina are situated behind the ear and as far away as possible from the incision site to ensure a maximal trajectory length of the catheter under the skin.</li>
		<li>Close the incision site in two layers.</li>
	</ol>
	</li>
	<li>Sternotomy
	<ol>
		<li>Make a median incision from the manubrium of the sternum to 3 cm below the xiphoid process until the sternum becomes apparent.</li>
		<li>Bluntly dissect caudally from the xiphoid process. Put a finger on the visceral side of the sternum and remove connective tissue as far as possible following the visceral sternal surface. 
		NOTE: The connective tissue is removed to prevent myocardial injury whilst performing sternotomy.</li>
		<li>Use the sternum saw to cleave the sternum. Control all bleeding sites. Use the sternum spreader to enlarge the access to the thoracic cavity. Avoid damaging the pleura.</li>
		<li>Open the pericardium carefully and use suspension sutures to keep it out of the surgical field.</li>
	</ol>
	</li>
	<li>Pacemaker lead placement (see Figure 1)
	<ol>
		<li>Place a pacemaker lead on the left atrium.
		<ol>
			<li>Test the extension and retraction mechanism of the lead&#39;s fixation screw. Then, put the tip on a (curved) forceps and curve the stylet by 60&#176; if necessary.</li>
			<li>Put a compress on the left ventricle and gently pull it aside to have a view of the left atrium. 
			NOTE: Pressure on the ventricle will quickly cause hypotension. Make sure the anesthesiologist anticipates this with low-dose norepinephrine through the CVC. Release the ventricle when the mean blood pressure drops below 40 mmHg for &#62;20 s. Only proceed when the blood pressure of the animal has normalized.</li>
			<li>Upon visualization of the left atrium, firmly put the lead tip on the left atrial free wall, as close as possible to the pulmonary veins and as far as possible from the ventricle. Screw it in by extending the helix into the atrial tissue, preferably with a slight inclination. Do this as fast as possible and release the pressure on the left ventricle immediately.</li>
			<li>Measure the sensing and pacing threshold and impedance of the lead using a programmable electrical stimulator or pacemaker programmer. Ensure that there is no ventricular overcapture (broad QRS on ECG) when pacing at high voltages (10 V). If not satisfied, retract the helix of the lead and start over from step 2.4.1.1. 
			NOTE: Normal pacing threshold should be &#60;1 V with a pulse width of 0.5 ms (typically ~0.5 V @0.5 ms).</li>
		</ol>
		</li>
		<li>Place a pacemaker lead on the right atrium, completely analogous to the placement of the left atrial lead.</li>
		<li>Ensure that both leads leave the thorax at the midline; the left atrial lead must be tunneled through the abdominal subcutaneous fat from the xiphoid process to the left flank, the right atrial lead to the right flank.</li>
		<li>Make a pacemaker pocket in the subcutaneous fat at the left and right flank of the pig. Connect the pacemakers to the leads and place them inside the pockets. Connect a pacemaker capable of performing (50 Hz) burst pacing with the left atrial lead (to allow pacing) and a pacemaker from a different manufacturer (in order to avoid crosstalk while reading out both pacemakers simultaneously) to the right atrial lead (to allow sensing). Close in 2 layers with classic single sutures, the inner layer with Vicryl 1-0 and the outer layer with Mersilene 0.</li>
	</ol>
	</li>
	<li>Induction of sterile pericarditis
	<ol>
		<li>Expose the atria again by gently pulling aside the ventricles. Cover up the ventricles with gauze (and take the gauze away afterward).</li>
		<li>Spray sterile talcum over the epicardial surface of both atria using the dispenser that is included in the pack. As bradycardia and hypotension will follow this manipulation, give the heart enough time to recover spontaneously after approximately one minute; if necessary, start or increase (the infusion rate of) a norepinephrine drip.</li>
		<li>Leave one layer of sterile gauze (5 cm x 5 cm) on the epicardial surface of both atria: one piece left and one right.</li>
		<li>Check the position of the pacemaker leads one last time before starting closure.</li>
	</ol>
	</li>
	<li>Closing the chest
	<ol>
		<li>Leave a drain in the mediastinum and tunnel it to the skin surface. Connect the drain to a sterile vacuum jar; open the connection when the first layer of the skin is closed (to avoid air leakage). Remove the drain when bringing the animal back to its stable.</li>
		<li>Close the pericardium with Prolene 6-0.</li>
		<li>Close the sternum using a classical cerclage technique with stainless steel wire.</li>
		<li>Close the subcutis in two layers with resorbable thread.</li>
		<li>Perform a sternal block by infiltrating 5 mL of 0.5% bupivacaine into the skin; ensure bone contact with the sternum to infiltrate the periosteum. 
		NOTE: Alternatively, it might be even better to use pre-emptive analgesia by performing the sternal block BEFORE incision of the sternum.</li>
		<li>Close the skin with a continuous intradermal suture using resorbable thread.</li>
	</ol>
	</li>
</ol>
3. Postoperative care
<ol>
	<li>Progressively, turn off all sedatives while closing the skin of the animal.</li>
	<li>Keep the animal in the surgery room with close monitoring of body temperature, ventilation and airway patency, oxygenation, and hemodynamic parameters.</li>
	<li>Due to a substantial drop in body temperature that frequently occurs during the procedure, keep the animal warm using blankets, heating pad, and hot packs. Provide oxygen during recovery, especially when shivering is noted.</li>
	<li>Apply a fentanyl patch of 50 &#181;g/h for postoperative analgesia. Because there is a delay of 6-8 h before the fentanyl patch becomes effective, administer 0.05-0.1 mg/kg of morphine subcutaneously to bridge this period.</li>
	<li>When the animal is stable, is showing an increase in body temperature; can lift its head; is swallowing; shows normal ocular reflexes; and is breathing spontaneously, freely, and deeply without an ETT in place, without signs of upper airway obstruction; it can be transported back to the pen. Provide means of heating during the recovery phase (e.g., infrared lamp, heating mat, blankets). 
	NOTE: Avoid putting the animal back in the pen too soon as respiratory arrest is possible, even hours after the cessation of narcotics.</li>
	<li>Perform a check-up on the animal: every 15 min during the first hour postoperatively, then hourly for the first 4&#8211;6 h or more frequently if the animal is not comfortable. When the animal shows signs of pain, administer supplementary morphine subcutaneously 0.025&#8211;0.05 mg/kg every 2 h until it is comfortable. Administer 1 g of cefazoline 8 and 16 h after surgery. 
	NOTE: Pain assessment consists of subjective elements such as attitude, behavior (standing, eating, drinking), and grimace. Objective signs of pain are elevated heart rate, elevated respiratory rate, and superficial respiration. The animal will return to its normal status and behavior within 24 h. Remove the fentanyl patch on day 3 post operation.</li>
</ol>
4. Atrial tachypacing for induction of AF
<ol>
	<li>Inject ketamine 10 mg/kg and midazolam 0.5 mg/kg intramuscularly (without atropine) and wait until a sufficient level of sedation is reached.</li>
	<li>Weigh the pig again for follow-up. Place the animal in a restraining sling and bring it to the operating theater.</li>
	<li>Attach ECG and oxygen saturation monitoring and place the programmer heads over their corresponding pacemakers. Interrogate the pacemakers.</li>
	<li>Check the pacemaker settings for the occurrence of spontaneous AF. Look for a ventricular lead warning when using a dual-chamber pacemaker.</li>
	<li>Determine impedance and sensing and pacing thresholds. When performing electrophysiology (EP) studies, always pace at twice the threshold voltage and watch for an increase in voltage threshold during the experiment.</li>
	<li>Determine the atrial effective refractory period (AERP) approximated by the shortest cycle length at which 1:1 capture is maintained during burst pacing. 
	NOTE: This method is different from clinical AERP determination but more relevant to this protocol.</li>
	<li>Determine the conduction time between left and right atrial leads by measuring the time between the initiation of the pacing spike and the atrial depolarization on the right atrial lead.</li>
	<li>For the first protocol, apply a burst pace for 20 s with a cycle length of AERP + 30 ms. After the cessation of the pacing, check for the presence of AF and measure how long the episode lasts. Pause for at least 5 s between each pacing session and wait until the sinus rhythm heart rate has recovered to baseline. Repeat this &#8805;10 times; note the display of the AF inducibility as a percentage-the proportion of &#34;successful&#34; attempts to the total amount of attempts to induce AF. 
	NOTE: Only episodes &#62; 5 s are considered relevant.</li>
	<li>For the second protocol, apply a burst pace for 20 s, starting with a cycle length of AERP + 20 ms. During the following burst, decrease the cycle length until the minimal cycle length with 1:1 capture. Repeat this at least 10 times. Note the AF duration and AF inducibility.</li>
	<li>For the third protocol, apply a burst pace for 5 s at 50 Hz. Repeat this at least 10 times. Note the AF duration and AF inducibility.</li>
	<li>Let the animal awaken or continue with other procedures (e.g., echocardiography, treatment, blood draw)</li>
</ol>
5. Euthanasia
<ol>
	<li>After the experiment &#9472; which lasted one month &#9472; the animals are euthanized with an overdose of IV pentobarbital (50 mg/kg, IV). Humane endpoints for euthanasia were persisting signs of severe pain or discomfort, despite adequate treatment. This is assessed clinically on a daily basis: alarming signs include hypertension, tachycardia, increased respiratory rate, behavioral changes (restlessness, immobilization, vocalization) and jaw clenching.</li>
</ol>
6. Sham surgery
<ol>
	<li>Perform the same protocol without spraying talcum over the atrial epicardium or leaving a layer of sterile gauze.</li>
</ol>

<ol><li>Hindricks, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((2020+ESC+Guidelines+for+the+diagnosis+and+management+of+atrial+fibrillation+developed+in+collaboration+with+the+European+Association+for+Cardio-Thoracic+Surgery+%28EACTS%29%3A+The+Task+Force+for+the+diagnosis+and+management+of+atrial+fibrillation+of+the+European+Society+of+Cardiology+%28ESC%29+Developed+with+the+special+contribution+of+the+European+Heart+Rhythm+Association+%28EHRA%29+of+the+ESC%5BTitle%5D)+AND+%22European+Heart+Journal%22%5BJournal%5D)">2020 ESC Guidelines for the diagnosis and management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS): The Task Force for the diagnosis and management of atrial fibrillation of the European Society of Cardiology (ESC) Developed with the special contribution of the European Heart Rhythm Association (EHRA) of the ESC.</a> European Heart Journal. 42 (5), 373(2021).</li>
<li>Sajeev, J. K., Kalman, J. M., Dewey, H., Cooke, J. C., Teh, A. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+atrium+and+embolic+stroke%3A+myopathy+not+atrial+fibrillation+as+the+requisite+determinant%5BTitle%5D)+AND+%22JACC.+Clinical+Electrophysiology%22%5BJournal%5D)">The atrium and embolic stroke: myopathy not atrial fibrillation as the requisite determinant.</a> JACC. Clinical Electrophysiology. 6 (3), 251-261 (2020).</li>
<li>Shen, M. J., Arora, R., Jalife, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Atrial+myopathy%5BTitle%5D)+AND+%22JACC%3A+Basic+to+Translational+Science%22%5BJournal%5D)">Atrial myopathy.</a> JACC: Basic to Translational Science. 4 (5), 640-654 (2019).</li>
<li>Jalife, J., Kaur, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Atrial+remodeling%2C+fibrosis%2C+and+atrial+fibrillation%5BTitle%5D)+AND+%22Trends+in+Cardiovascular+Medicine%22%5BJournal%5D)">Atrial remodeling, fibrosis, and atrial fibrillation.</a> Trends in Cardiovascular Medicine. 25 (6), 475-484 (2015).</li>
<li>Fu, X. X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Interleukin-17A+contributes+to+the+development+of+post-operative+atrial+fibrillation+by+regulating+inflammation+and+fibrosis+in+rats+with+sterile+pericarditis%5BTitle%5D)+AND+%22International+Journal+of+Molecular+Medicine%22%5BJournal%5D)">Interleukin-17A contributes to the development of post-operative atrial fibrillation by regulating inflammation and fibrosis in rats with sterile pericarditis.</a> International Journal of Molecular Medicine. 36 (1), 83-92 (2015).</li>
<li>Liao, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((TRPV4+blockade+suppresses+atrial+fibrillation+in+sterile+pericarditis+rats%5BTitle%5D)+AND+%22JCI+Insight%22%5BJournal%5D)">TRPV4 blockade suppresses atrial fibrillation in sterile pericarditis rats.</a> JCI Insight. 5 (23), 137528(2020).</li>
<li>Zhang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Role+of+inflammation+in+the+initiation+and+maintenance+of+atrial+fibrillation+and+the+protective+effect+of+atorvastatin+in+a+goat+model+of+aseptic+pericarditis%5BTitle%5D)+AND+%22Molecular+Medicine+Reports%22%5BJournal%5D)">Role of inflammation in the initiation and maintenance of atrial fibrillation and the protective effect of atorvastatin in a goat model of aseptic pericarditis.</a> Molecular Medicine Reports. 11 (4), 2615-2623 (2015).</li>
<li>Vizzardi, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Risk+factors+for+atrial+fibrillation+recurrence%3A+a+literature+review%5BTitle%5D)+AND+%22Journal+of+Cardiovascular+Medicine%22%5BJournal%5D)">Risk factors for atrial fibrillation recurrence: a literature review.</a> Journal of Cardiovascular Medicine. 15 (3), Hagerstown, Md. 235-253 (2014).</li>
<li>Dosdall, D. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Chronic+atrial+fibrillation+causes+left+ventricular+dysfunction+in+dogs+but+not+goats%3A+experience+with+dogs%2C+goats%2C+and+pigs%5BTitle%5D)+AND+%22American+Journal+of+Physiology.+Heart+and+Circulatory+Physiology%22%5BJournal%5D)">Chronic atrial fibrillation causes left ventricular dysfunction in dogs but not goats: experience with dogs, goats, and pigs.</a> American Journal of Physiology. Heart and Circulatory Physiology. 305 (5), 725-731 (2013).</li>
<li>Schuttler, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Animal+models+of+atrial+fibrillation%5BTitle%5D)+AND+%22Circulation+Research%22%5BJournal%5D)">Animal models of atrial fibrillation.</a> Circulation Research. 127 (1), 91-110 (2020).</li>
<li>Wijffels, M. C., Kirchhof, C. J., Dorland, R., Allessie, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Atrial+fibrillation+begets+atrial+fibrillation.+A+study+in+awake+chronically+instrumented+goats%5BTitle%5D)+AND+%22Circulation%22%5BJournal%5D)">Atrial fibrillation begets atrial fibrillation. A study in awake chronically instrumented goats.</a> Circulation. 92 (7), 1954-1968 (1995).</li>
<li>Willems, R., Ector, H., Holemans, P., Van De Werf, F., Heidbuchel, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Effect+of+different+pacing+protocols+on+the+induction+of+atrial+fibrillation+in+a+transvenously+paced+sheep+model%5BTitle%5D)+AND+%22Pacing+and+Clinical+Electrophysiology%22%5BJournal%5D)">Effect of different pacing protocols on the induction of atrial fibrillation in a transvenously paced sheep model.</a> Pacing and Clinical Electrophysiology. 24 (6), 925-932 (2001).</li>
<li>Pagé, P. L., Plumb, V. J., Okumura, K., Waldo, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+new+animal+model+of+atrial+flutter%5BTitle%5D)+AND+%22Journal+of+the+American+College+of+Cardiology%22%5BJournal%5D)">A new animal model of atrial flutter.</a> Journal of the American College of Cardiology. 8 (4), 872-879 (1986).</li>
<li>Schwartzman, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+plasma-based%2C+amiodarone-impregnated+material+decreases+susceptibility+to+atrial+fibrillation+in+a+post-cardiac+surgery+model%5BTitle%5D)+AND+%22Innovations%22%5BJournal%5D)">A plasma-based, amiodarone-impregnated material decreases susceptibility to atrial fibrillation in a post-cardiac surgery model.</a> Innovations. 11 (1), Philadelphia, Pa. 59-63 (2016).</li>
<li>BCFI vzw. Vetcompendium BCFIvet. , Available from: 
 <a target="_blank" href="https://www.vetcompendium.be/nl">https://www.vetcompendium.be/nl</a> (2021).</li>
<li><a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=%22Swine+in+the+laboratory.+Surgery%2C+anesthesia%2C+imaging%2C+and+experimental+techniques%2C+Third+edition%22">Swine in the laboratory. Surgery, anesthesia, imaging, and experimental techniques, Third edition</a>. Swindle, M. M., Smith, A. C. , CRC Press. (2016).</li>
<li>Unit for Laboratory Animal Medicine. Guidelines on anesthesia and analgesia in swine. , Available from: 
 <a target="_blank" href="https://az.research.umich.edu/animalcare/guidelines/guidelines-anesthesia-and-analgesia-swine">https://az.research.umich.edu/animalcare/guidelines/guidelines-anesthesia-and-analgesia-swine</a> (2021).</li>
<li>Ettrup, K. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Basic+surgical+techniques+in+the+Gottingen+minipig%3A+intubation%2C+bladder+catheterization%2C+femoral+vessel+catheterization%2C+and+transcardial+perfusion%5BTitle%5D)+AND+%22Journal+of+Visualized+Experiments%3A+JoVE%22%5BJournal%5D)">Basic surgical techniques in the Gottingen minipig: intubation, bladder catheterization, femoral vessel catheterization, and transcardial perfusion.</a> Journal of Visualized Experiments: JoVE. (52), e2652(2011).</li>
</ol>

None of the authors have any conflict of interest to disclose.

A reliable large animal model is a major asset for the study of atrial myopathy and AF and the development of novel therapies for AF. Implantation of pacemaker leads on the atrial epicardium allowed a longitudinal follow-up and repetitive electrophysiologic testing, which is difficult in small animals. Minipigs are easy to handle, and their hearts are structurally and physiologically similar to the human heart10.
The sterile pericarditis model is relatively straightforw...

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, leading to significant morbidity, mortality, and healthcare expenses1. In many cases, AF is merely the electrical symptom of the underlying atrial myopathy, which is defined by structural, electrical, autonomic, and contractile remodeling of the atria. This atrial myopathy can lead to AF and stroke2,3. Most therapies only target the electrical remodeling but do not target the underlying structural changes in the atria (inflammation and fibrosis)4,5,6,7. This is probably one of the reasons why current therapies are only marginally effective, especially in more advanced atrial myopathy8.
A reproducible animal model is crucial to target the inflammation and fibrosis present in atrial myopathy. Atrial tachypacing models have been developed in several large animal species9,10,11,12. In these models, the atrial tissue is paced continuously for long periods to induce electrical and eventually structural changes. The major disadvantages of tachypacing models are the long duration before structural signs of atrial myopathy appear and their relevance only for clinical syndromes in which electrical abnormalities develop before the atrial myopathy. A theoretical risk is pacing-lead failure due to fibrosis during long follow-up9.
In models of sterile pericarditis, sterile talcum is sprayed over the epicardial surface of the atria to induce an acute inflammatory and fibrotic reaction, resulting in atrial myopathy13,14. Pigs have cardiac anatomy and physiology similar to that of humans, and therefore, porcine models have high translational relevance. The advantages of using minipigs are that they are easier to handle due to their smaller size than conventional pig strains and can be maintained for a long period without any significant increase in body weight10. All these reasons make sterile pericarditis in minipigs an excellent model for the investigation of atrial myopathy and fibrillation. This protocol and video aim to facilitate the setup of this model in different research facilities and standardize protocols to study the inducibility of AF.

<table><tbody><tr><td>Aachener minipig, 6-months old, male, castrated, weight 15-25 kg</td><td>Carfil</td><td></td><td></td></tr><tr><td>&lt;em&gt;&lt;u&gt;&lt;strong&gt;Anesthesia and preparation&lt;/strong&gt;&lt;/u&gt;&lt;/em&gt;</td><td></td><td></td><td></td></tr><tr><td>ECG electrodes</td><td></td><td></td><td></td></tr><tr><td>Endotracheal tube 6.5 mm ID</td><td>Covidien</td><td>115-65OR</td><td></td></tr><tr><td>External cardioverter-defibrillator</td><td>Innomed</td><td>Cardio-aid 200B</td><td></td></tr><tr><td>Heating pad</td><td>OK.</td><td>OUB 60321</td><td></td></tr><tr><td>Intravenous catheter 22 GA, 1 Inch</td><td>BD</td><td>381323</td><td></td></tr><tr><td>Laryngoscope blade size 4</td><td>Miller</td><td>SUS426601</td><td></td></tr><tr><td>Monitor</td><td>GE Medical systems</td><td>2600040-003</td><td></td></tr><tr><td>Respirator</td><td>Datex-Ohmeda</td><td>1009-9000-000</td><td></td></tr><tr><td>Shaver</td><td>Aesculap</td><td>GT 104 / REF 985203</td><td></td></tr><tr><td>Syringe driver pump</td><td>Fresenius Kabi</td><td>082470</td><td></td></tr><tr><td>&lt;u&gt;&lt;em&gt;&lt;strong&gt;Arterial and central venous line placement&lt;/strong&gt;&lt;/em&gt;&lt;/u&gt;</td><td></td><td></td><td></td></tr><tr><td>3-lumen central venous catheterization set, 7 French, 16 cm, 0.032 Inch guide</td><td>Arrow medical</td><td>EU-22703-EN</td><td></td></tr><tr><td>Arteral catheter 3 French, 8 cm</td><td>Vygon</td><td>1,15,090</td><td></td></tr><tr><td>Caresite Luer access device</td><td>B. Braun</td><td>415122-01</td><td></td></tr><tr><td>Fluids: IV bags of Plasmalyte, Glucose 5%, NaCl 0.9% (500 mL or 1000 mL)</td><td></td><td></td><td></td></tr><tr><td>heparinized saline</td><td></td><td></td><td></td></tr><tr><td>Needles: 18 Ga / 40 mm and 22 Ga / 40 mm</td><td></td><td></td><td></td></tr><tr><td>Pressure monitoring set, 195 cm</td><td>Edwards Lifesciences</td><td>T005021M</td><td></td></tr><tr><td>Pressure tubing 180 cm</td><td>Edwards Lifesciences</td><td>50P172</td><td></td></tr><tr><td>suture with needle</td><td></td><td></td><td></td></tr><tr><td>Syringes Luerlok: 2 mL, 5 mL, 10 mL, 20 mL, 50 mL</td><td></td><td></td><td></td></tr><tr><td>Ultrasound gel</td><td>Zealand coating</td><td>446-1</td><td></td></tr><tr><td>Ultrasound with vascular probe</td><td>Philips healthcare</td><td>EPIQ 7C / REF BZE1723</td><td></td></tr><tr><td>&lt;u&gt;&lt;em&gt;&lt;strong&gt;Surgical set&lt;/strong&gt;&lt;/em&gt;&lt;/u&gt;</td><td></td><td></td><td></td></tr><tr><td>Blunt-tip surgical scissors</td><td>Martin</td><td>11-934-25</td><td></td></tr><tr><td>60 degrees curved Debakey forceps</td><td>Aesculap</td><td>FB403</td><td></td></tr><tr><td>Anatomical forceps</td><td>AS</td><td>13-102-16</td><td></td></tr><tr><td>Debakey forceps</td><td>Geister</td><td>10-0634</td><td></td></tr><tr><td>Electrocautery module</td><td>Alsa</td><td>Alsatom SU 140/D MPC</td><td></td></tr><tr><td>Holders for stainless steel wire</td><td>COBE</td><td>013-123</td><td></td></tr><tr><td>Mosquito</td><td>Leibinger</td><td>32-01008</td><td></td></tr><tr><td>Needledriver, fine</td><td>Delacroix-Chevalier</td><td>50302-21</td><td></td></tr><tr><td>Needledriver, normal</td><td>Aesculap</td><td>BM 77</td><td></td></tr><tr><td>Rib spreader</td><td>Martin</td><td>24-178-01</td><td></td></tr><tr><td>Scalpel</td><td>Swann-Morton</td><td>0511</td><td>no. 24</td></tr><tr><td>Scissors for stainless steel wire</td><td>Jakobi</td><td>411830</td><td></td></tr><tr><td>Spreaders</td><td>AS</td><td>16-058-00</td><td></td></tr><tr><td>Sternum saw</td><td>Eure-Power</td><td>5000020</td><td></td></tr><tr><td>Sternum saw blade</td><td>MicroAire</td><td>ZR-032M</td><td></td></tr><tr><td>&lt;u&gt;&lt;em&gt;&lt;strong&gt;Surgical consumables&lt;/strong&gt;&lt;/em&gt;&lt;/u&gt;</td><td></td><td></td><td></td></tr><tr><td>Disinfectant: iodine, chlorhexidine</td><td></td><td></td><td></td></tr><tr><td>Electrocautery pencil with push button, cable 5 m</td><td>Dongguan QueenMed Equipment</td><td>ESPB4001LQ</td><td></td></tr><tr><td>Gastric tube</td><td>Vygon</td><td>390.12</td><td></td></tr><tr><td>Mersilene-0, 75 cm</td><td>Ethicon</td><td>F2505H</td><td></td></tr><tr><td>Monocryl 3-0, 70 cm</td><td>Ethicon</td><td>Y423H</td><td></td></tr><tr><td>Mouth masks, hair nets</td><td></td><td></td><td></td></tr><tr><td>Oriflex-4 vacuum flask for surgical draining</td><td>Oriplast Krayer</td><td>VK00352</td><td></td></tr><tr><td>Prolene 6-0, 75 cm</td><td>Ethicon</td><td>8711H</td><td></td></tr><tr><td>Stainless steel monofilament non-absorbable suture</td><td>Ethicon</td><td>W995</td><td></td></tr><tr><td>Sterile drapes</td><td>3M</td><td>9010</td><td></td></tr><tr><td>Sterile gauze 20 x 10 cm</td><td>Stella</td><td>35921</td><td></td></tr><tr><td>Sterile gloves</td><td></td><td></td><td></td></tr><tr><td>Sterile surgical gown</td><td></td><td></td><td></td></tr><tr><td>Steritalc PF3</td><td>Novatech</td><td>16863</td><td></td></tr><tr><td>Vicryl-0, 75 cm</td><td>Ethicon</td><td>V324H</td><td></td></tr><tr><td>&lt;u&gt;&lt;em&gt;&lt;strong&gt;Cardiac pacing&lt;/strong&gt;&lt;/em&gt;&lt;/u&gt;</td><td></td><td></td><td></td></tr><tr><td>Bipolar pacing lead Fineline II Sterox EZ 58 cm</td><td>Boston Scientific</td><td>4474</td><td></td></tr><tr><td>Bipolar pacing lead Tendril STS 58 cm</td><td>Abbott</td><td>2088TC</td><td></td></tr><tr><td>Ellegaard G&amp;ouml;ttingen Minipig Frame 3</td><td>Lomir</td><td>DF H1PU</td><td></td></tr><tr><td>Ellegaard G&amp;ouml;ttingen Minipig Sling Cover</td><td>Lomir</td><td>SS CEG1</td><td></td></tr><tr><td>Micropace cardiac stimulator</td><td>Boston Scientific</td><td>EPS 320</td><td></td></tr><tr><td>Pacemaker for pacing</td><td>Medtronic</td><td>Azure XT DR MRI SureScan</td><td></td></tr><tr><td>Pacemaker for sensing</td><td>Biotronik</td><td>Eluna 8 DR-T</td><td></td></tr><tr><td>Pacemaker programmer for pacing</td><td>Medtronic</td><td>CareLink Encore 29901A</td><td></td></tr><tr><td>Pacemaker programmer for sensing</td><td>Biotronik</td><td>ICS 3000 DS CD-W US</td><td></td></tr><tr><td>&lt;u&gt;&lt;em&gt;&lt;strong&gt;Medication&lt;/strong&gt;&lt;/em&gt;&lt;/u&gt;</td><td></td><td></td><td></td></tr><tr><td>Adrenaline 1 mg/mL, 1 mL</td><td>Sterop</td><td></td><td></td></tr><tr><td>Atropine 0.5 mg/mL, 1 mL</td><td>Sterop</td><td></td><td></td></tr><tr><td>Catapressan 150 &amp;micro;g/mL, 1 ml clonidine</td><td>Boehringer Ingelheim</td><td>BE021402</td><td></td></tr><tr><td>Cefazoline 2 g powder</td><td>Mylan</td><td>BE319794</td><td></td></tr><tr><td>Cordarone 50 mg/mL, 3 mL amiodarone</td><td>Sanofi</td><td></td><td></td></tr><tr><td>Durogesic 50 &amp;micro;g/h fentanyl patches</td><td>Janssen-Cilag</td><td></td><td></td></tr><tr><td>Glucose 5%, 500 mL</td><td>Baxter</td><td>AE0063</td><td></td></tr><tr><td>Ketalar 50 mg/mL, 10 mL</td><td>Pfizer</td><td>804101</td><td></td></tr><tr><td>Lanoxin 0.25 mg/mL, 2 mL digoxine</td><td>Aspen</td><td></td><td></td></tr><tr><td>Marcaine 0.5% + adrenaline 1:200,000</td><td>Aspen</td><td></td><td></td></tr><tr><td>Midazolam 5 mg/ml, 3 mL</td><td>B. Braun</td><td>3521740</td><td></td></tr><tr><td>Morfine 10 mg/mL, 1 mL</td><td>Sterop</td><td></td><td></td></tr><tr><td>NaCl 0.9%, 500 mL</td><td>Baxter</td><td>AKE1323</td><td></td></tr><tr><td>Nitro Pohl 1 mg/mL, 5 mL nitroglycerine</td><td>Pohl Boskamp</td><td></td><td></td></tr><tr><td>Noradrenaline 1 mg/mL, 4 mL</td><td>Aguettant</td><td></td><td></td></tr><tr><td>Plasmalyte 1000 mL</td><td>Baxter</td><td>AKE0324</td><td></td></tr><tr><td>Propofol 10 mg/mL, 20 mL</td><td>B. Braun</td><td>3521810</td><td></td></tr><tr><td>Protamine 1400 IU/mL, 5 mL</td><td>Leo pharma</td><td></td><td></td></tr><tr><td>Rapifen 0.5 mg/mL, 2 mL</td><td>Janssen-Cilag</td><td>95103</td><td></td></tr><tr><td>Seloken 1 mg/mL, 5 mL metoprolol</td><td>AstraZeneca</td><td></td><td></td></tr><tr><td>Sevorane Quick Fill 100% sevoflurane, 250 mL</td><td>Abbvie</td><td>1283-415</td><td></td></tr><tr><td>Tracrium 10 mg/mL, 5 mL atracurium</td><td>Aspen</td><td></td><td></td></tr></tbody></table>

sterile pericarditis in aachener minipigs as a model for atrial myopathy and atrial fibrillation

Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia caused by structural remodeling of the atria, also called atrial myopathy. Current therapies only target the electrical abnormalities and not the underlying atrial myopathy. For the development of novel therapies, a reproducible large animal model of atrial myopathy is necessary. This paper presents a model of sterile pericarditis-induced atrial myopathy in Aachener minipigs. Sterile pericarditis was induced by spraying sterile talcum and leaving a layer of sterile gauze over the atrial epicardial surface. This led to inflammation and fibrosis, two crucial components of the pathophysiology of atrial myopathy, making the atria susceptible to the induction of AF. Two pacemaker electrodes were positioned epicardially on each atrium and connected to two pacemakers from different manufacturers. This strategy allowed for repeated non-invasive atrial programmed stimulation to determine the inducibility of AF at specified time points after surgery. Different protocols to test AF inducibility were used. The advantages of this model are its clinical relevance, with AF inducibility and the rapid induction of inflammation and fibrosis-both present in atrial myopathy-and its reproducibility. The model will be useful in the development of novel therapies targeting atrial myopathy and AF.

Morbidity and mortality: 
When we started developing this model of sterile pericarditis in Aachener minipigs, we noticed perioperative mortality of 4 out of 17 pigs (23.5%): 3 out of 4 deaths occurred in the first 6 surgeries because of a "learning curve effect." The etiologies were the following: 2 pigs died because of postoperative respiratory arrest; this problem was solved by reducing the dose of alfentanil. One pig died because of ventricular fibrillation during the first pacing session and one d...

We describe a sterile pericarditis model in minipigs to study atrial myopathy and atrial fibrillation (AF). We present surgical and anesthetic techniques, strategies for vascular access, and a protocol to study the inducibility of AF.

Atrial fibrillation (AF) is the most common arrhythmia caused by structural remodeling of the atria, also called atrial myopathy. Current therapies only ...

sterile-pericarditis-aachener-minipigs-as-model-for-atrial-myopathy

Research

JoVE Journal

Medicine

This protocol describes the porcine myocardial infarction (MI) model using a 90 min closed-chest coronary balloon occlusion of the left anterior descending artery (LAD), followed by reperfusion. Furthermore, the protocol for several outcome parameters, such as cardiac function, hemodynamics, microvascular resistance, and infarct size, are also presented.

Myocardial Infarction and Functional Outcome Assessment in Pigs

Here we demonstrate a protocol to standardize sampling procedures of an established porcine model of acute myocardial infarction in order to increase its translational value in the understanding of the pathophysiology of myocardial ischemia/reperfusion injury and to test novel drug candidates.

Improvement of a Closed Chest Porcine Myocardial Infarction Model by Standardization of Tissue and Blood Sampling Procedures

Here, we present a protocol to produce tachycardia-induced cardiomyopathy in swine. This model represents a potent way to study the hemodynamics of progressive chronic heart failure and the effects of applied treatment.

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

Here, we describe an optimized, Langendorff-based procedure for the isolation of single-cell atrial cardiomyocytes from a rat model of metabolic syndrome-related heart failure with preserved ejection fraction. A manual regulation of intraluminal pressure of cardiac cavities is implemented to yield functionally intact myocytes suitable for excitation-contraction-coupling studies.

Isolation of Atrial Cardiomyocytes from a Rat Model of Metabolic Syndrome-related Heart Failure with Preserved Ejection Fraction

Here we present a protocol for the induction of left ventricular cryoinjury followed by the implantation of a cardiac muscle patch, derived from human iPS-cell cardiomyocytes in a guinea pig model.

Implantation of hiPSC-derived Cardiac-muscle Patches after Myocardial Injury in a Guinea Pig Model

The overall goal of the current study is to present the techniques of induction of myocardial infarction (MI) and post-myocardial infarction heart failure (post-MI HF) in closed-chest, adult Göttingen minipigs and the characterization of post-MI HF model in Göttingen minipigs as compared to Landrace pigs.

Post-Myocardial Infarction Heart Failure in Closed-chest Coronary Occlusion/Reperfusion Model in G&#246;ttingen Minipigs and Landrace Pigs

The present protocol describes a step-by-step procedure to establish a minipig model of heart failure with preserved ejection fraction using descending aortic constriction. The methods for evaluating cardiac morphology, histology, and function of this disease model are also presented.

A Surgical Model of Heart Failure with Preserved Ejection Fraction in Tibetan Minipigs

The present protocol describes the optimization of experimental parameters when using transesophageal atrial pacing to assess atrial fibrillation susceptibility in mice.

Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice

We present a minimally invasive leporine model of long-term cardiac pacing that can be utilized for artificial pacing and heart failure development in preclinical studies.

Translational Rabbit Model of Chronic Cardiac Pacing

This report provides a detailed description of the methodology and results of simultaneous endocardial and epicardial optical mapping of electrical excitation in the intact left atrium of a Langendorff-perfused sheep heart during stretch-induced atrial fibrillation.

High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation

Learn sterile pericarditis techniques in Aachener minipigs to model atrial myopathy and atrial fibrillation. This method enables rapid disease induction and repeated electrophysiology studies for pre-clinical research.

Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation

Explore More Videos