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 int...

<ol>
	<li>Hindricks, G., 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=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.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+atrium+and+embolic+stroke:+myopathy+not+atrial+fibrillation+as+the+requisite+determinant.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atrial+myopathy.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atrial+remodeling,+fibrosis,+and+atrial+fibrillation.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interleukin-17A+contributes+to+the+development+of+post-operative+atrial+fibrillation+by+regulating+inflammation+and+fibrosis+in+rats+with+sterile+pericarditis.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TRPV4+blockade+suppresses+atrial+fibrillation+in+sterile+pericarditis+rats.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&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.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Risk+factors+for+atrial+fibrillation+recurrence:+a+literature+review.">Risk factors for atrial fibrillation recurrence: a literature review.</a> Journal of Cardiovascular Medicine. 15 (3), 235-253 (2014).</li><li>Dosdall, D. J., 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=Chronic+atrial+fibrillation+causes+left+ventricular+dysfunction+in+dogs+but+not+goats:+experience+with+dogs,+goats,+and+pigs.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+of+atrial+fibrillation.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atrial+fibrillation+begets+atrial+fibrillation.+A+study+in+awake+chronically+instrumented+goats.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+different+pacing+protocols+on+the+induction+of+atrial+fibrillation+in+a+transvenously+paced+sheep+model.">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>Pag&#233;, P. L., Plumb, V. J., Okumura, K., Waldo, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+animal+model+of+atrial+flutter.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+plasma-based,+amiodarone-impregnated+material+decreases+susceptibility+to+atrial+fibrillation+in+a+post-cardiac+surgery+model.">A plasma-based, amiodarone-impregnated material decreases susceptibility to atrial fibrillation in a post-cardiac surgery model.</a> Innovations. 11 (1), 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>Swindle, M. M., Smith, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Swine in the laboratory. Surgery, anesthesia, imaging, and experimental techniques, Third edition. , (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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basic+surgical+techniques+in+the+Gottingen+minipig:+intubation,+bladder+catheterization,+femoral+vessel+catheterization,+and+transcardial+perfusion.">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>

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 border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<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>Anesthesia and preparation</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>Arterial and central venous line placement</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>Surgical set</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>Surgical consumables</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>Cardiac pacing</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&#246;ttingen Minipig Frame 3</td>
			<td>Lomir</td>
			<td>DF H1PU</td>
			<td></td>
		</tr>
		<tr>
			<td>Ellegaard G&#246;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>Medication</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 &#181;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 &#181;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

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 &#34;learning curve effect.&#34; 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...

Watch this Scientific Journal Video about Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation at JoVE.com

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

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 ...

Atrial myopathy can result in atrial fibrillation, which is the most common arrhythmia in humans. The sterile pericarditis model is a reliable, large animal model that resembles the pathogenesis of atrial myopathy. This model provides a rapid induction of atrial myopathy within a matter of weeks.Also, repeated electrophysiology studies can easily be performed in a follow up period without the need of repeated catheterizations. Because of the similarity in anatomy and physiology compared to humans, the minipig model presented here can be used to study the pathophysiology of atrial myopathy and atrial fibrillation, but can also be used in pre-clinical drug discovery. Begin by preparing the pressure conducting system.Add 5, 000 international units of heparin to an IV bag with 500 milliliters of 0.9%saline. Place the animal in the supine position, then extend the leg and locate the femoral artery using ultrasound with the vascular probe in the carotid setting. Disinfect the inguinal zone with chlorhexidine.Puncture the femoral artery using ultrasound guidance and insert a 3 French sheath using the Seldinger technique. Fixate the sheath with the suture and connect it to the transducer to flush. Monitor the arterial blood pressure in real time.Make a five centimeter incision in the groove at the medial border of the sternocleidomastoid muscle. Then bluntly dissect until the internal jugular vein is reached. Remove fibrous tissue around the vein and place a Prolene 6 by 0 squared suture around the desired catheterization site to gain vessel control.Cannulate the internal jugular vein with a 3 French triple-lumen CVC using the Seldinger technique. Then tighten the Prolene 6-0 suture around the catheter. Fixate the handle of the catheter to the sternocleidomastoid muscle.Tunnel the three catheter lumina separately and attach the ends firmly to the skin. Put on the needle free injection port, then close the incision site in two layers. Make a median incision manubrium of the sternum to three centimeters below the xiphoid process until the sternum becomes apparent.Bluntly dissect caudally from the xiphoid process. Put a finger or blunt dissecting scissors on the visceral side of the sternum and remove connective tissue following the visceral sternal surface as far as possible. Use the sternum saw to cleave the sternum.Then use the sternum spreader to enlarge the access to the thoracic cavity, avoiding damaging the pleura. Open the pericardium carefully and use suspension sutures to keep it out of the surgical field. After testing the extension and retraction mechanism of the lead's fixation screw, put the lead tip on a curved forceps and curve the stylet by 60 degrees, if necessary.Put a compress on the left ventricle and gently pull it aside to gain a view of the left atrium. Upon visualization of the left atrium, firmly put the lead tip on its 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.Work quickly and release the pressure on the left ventricle immediately. Measure the sensing and pacing threshold and impedance of the lead using a programmable electrical stimulator or pacemaker program. Ensuring that there is no ventricular over capture when pacing at high voltages.Place a pacemaker lead on the right atrium completely analogous to the placement of the left atrial lead. Ensuring 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 and the right atrial lead to the right flank.Make a pacemaker pocket in the subcutaneous fat at the left and right flank of the pig. Connect a pacemaker capable of performing 50 Hertz burst pacing with the left atrial lead, and a pacemaker from a different manufacturer with the right atria lead, then place them inside the pockets. Expose the atria again by gently pulling aside the ventricles, then cover the ventricles with gauze.Spray sterile talcum over the epicardial surface of both atria using the dispenser. Leave one layer of sterile gauze on the epicardial surface of the atria. Check the position of the pacemaker leads one last time before starting closure.Close the pericardium using monocryl 3-0 and the sternum using the stainless steel wire, then close subcutaneous and the skin using Vicryl zero and monocryl 3-0, respectively. After the sternal wound has healed, weigh the pig again for follow up, then place the animal in a restraining sling and bring it to the operating theater. Attach ECG and saturation monitoring and place the programmer heads over their corresponding pacemakers.Interrogate the pacemaker. Check the pacemaker settings for the occurrence of spontaneous AF.A ventricular warning is normal when using a dual chamber pacemaker. Determine impedance and sensing and pacing thresholds.Determine the atrial effective refractory period approximated by the shortest cycle length at which a one-to-one ratio capture is maintained during burst pacing. 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. Perform three protocols as described in the text manuscript.Noting the AF duration and the AF inducibility for each protocol, then allow the animal to awaken or continue with other procedures. A gradual increase in the voltage threshold and impedance of the left atrial lead were observed over time, indicating increased fibrosis. Detrimental pacing and 50 Hertz burst pacing protocols were more successful than the AERP plus 30 milliseconds pacing protocol.AF inducibility began to increase two weeks after surgery up to approximately 25%The AERP plus 30 millisecond protocol was the least effective, showing approximately 10%AF inducibility. Detrimental pacing and 50 Hertz burst pacing increased AF inducibility to approximately 40%This atrial electrogram of the left atrial pacemaker shows induction of an episode of AF after five seconds of 50 Hertz burst pacing. Whereas in this one, there is no AF induction.Masson's trichrome staining of left atrial tissue showed higher levels of interstitial or paravascular fibrosis in the sterile pericarditis animals compared to shams. Blinded quantification of the percentage of blue fibrotic tissue area relative to the total myocardial area showed that sterile pericarditis induces more paravascular and interstitial fibrosis in atrial tissue than sham surgery. The most important thing is to obtain good positioning of the pacemaker leads with adequate voltage threshold and without ventricular capture.It is very difficult to correct problems with pacemaker leads after the initial surgery because the extensive fibrosis observed in this model prohibits replacement of the leads. This protocol focuses on the surgical and electrophysiological studies, but the model can also be used for histology and cardiac imaging, including CT and MRI. Also, compared to rodents, the larger quantity of atrial tissue allows for detailed transcriptomic and proteomic studies.

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

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JoVE Journal

Medicine

2.5K Views.  University of Antwerp. Atrial myopathy can result in atrial fibrillation, which is the most common arrhythmia in humans. The sterile pericarditis model is a reliable, large animal model that resembles the pathogenesis of atrial myopathy. This model provides a rapid induction of atrial myopathy within a matter of weeks.Also, repeated electrophysiology studies can easily be performed in a follow up period without the need of repeated catheterizations. Because of the similarity in anatomy and physiology compare...