We would like to give a big thanks to the Visible Heart Laboratory staff and students that have helped with this project: Nate Menninga, Lars Mattison and Megan Schmidt.

Questo protocollo è stato approvato dalla University of Minnesota Istituzionale cura degli animali e del Comitato uso. <img alt="Figura 1" src="/files/ftp_upload/52600/52600fig1.jpg" /> Figura 1. Schema di studio paradigma <a href="https://www.jove.com/files/ftp_upload/52600/52600fig1large.jpg" target="_blank">Cliccate qui per vedere una versione più grande di questa figura.</a> 1. Preparazione chirurgica del suina <ol><li> Somministrare 5-7mg / kg di tiletamina / zilazipam al suina (70-80 kg) mediante iniezione intramuscolare. Inserire un catetere venoso orecchio e amministrare 5-7 mg / kg methohexital tramite l&#39;accesso per via endovenosa. Intubare l&#39;animale con tubo endotracheale e ventilare. </li><li> Invia isoflurano&gt; 1,2% MAC in una miscela di aria e ossigeno casa per mantenere un piano chirurgica di anestesia. Assicurarsi che l&#39;animale è in un profondo piano di Anesthesia prima di eventuali manipolazioni controllando l&#39;assenza di tono mascella e mantenendo le anestesia sopra la concentrazione minima alveolare per suini. controllo profondità dell&#39;anestesia iniziale è condotta garantendo l&#39;assenza di tono mascella e il livello isoflurano sono costantemente monitorati durante tutta la procedura (&gt; 1,5 MAC) per garantire una profonda piano di anestesia. </li><li> accedere con attenzione il diritto giugulare e carotide esterna con cauterizzazione e la dissezione smussa. Posizionare un catetere di Swan-Ganz 8.5F nella giugulare esterna e gonfiare il palloncino a 1,5 cc. Poi attraversare attraverso l&#39;atrio destro, nel ventricolo e attraverso la valvola polmonare verso il basso l&#39;arteria polmonare fino a quando non si avverte una pressione di cuneo. </li><li> Sgonfiare il palloncino e lasciare il catetere in questa posizione. Registrare la pressione atriale destra e della pressione arteriosa polmonare con il palloncino. Inoltre, registrare la pressione cuneo o pressione nel polmone (o se i polmoni sono considerati normali, quindi anche registrare sinistra unpressione di prova). NOTA: Questo catetere consente anche stime della gittata cardiaca. </li><li> Inserire un ulteriore 5.0f pressione catetere a palloncino nella giugulare esterna e nel ventricolo destro di pressione continuamente record. </li><li> Inserire un 5.0f balloon pressione catetere in arteria carotide, prolasso attraverso la valvola aortica e mantenere nel ventricolo sinistro. Lavare tutti i cateteri a pressione con 20 unità / ml di soluzione fisiologica heparanized collegato ad un trasduttore di pressione, e registrare tutti i dati di pressione del ventricolo sinistro, ventricolo destro (e stima gittata cardiaca), la pressione arteriosa polmonare e la pressione atriale destra. </li><li> Per il monitoraggio periferico, accedere ad un ramo dell&#39;arteria femorale posizionando un catetere 18F per la pressione sanguigna in tempo reale o monitoraggio dei gas del sangue. frequenza cardiaca Record e la temperatura durante il procedimento. </li><li> accedere con cautela la giugulare esterna sinistra con cauterizzazione e la dissezione smussa. Inserire due introduttori emostasi 11.0F nel jugular e sicuro con 0 punti di sutura in seta. Mettere cateteri orientabili nelle introduttori. </li><li> Sotto guida fluoroscopica, luogo di fissazione attiva conduce in appendice atriale destra e l&#39;apice del ventricolo destro. NOTA: Un cavo di fissaggio è un filo impiantato chirurgicamente che collega il cuore ad un pacemaker impiantato. </li><li> cavi Connectanalyzer ai cavi e di prova per la cattura utilizzando un programmatore. Impostare i parametri per 8V, 0.25 la durata msec, e impostare la frequenza di stimolazione ad un minimo di 10 bpm superiore al tasso di intrinseca in quel momento. Registrare l&#39;impedenza relativa per ogni piombo. </li><li> Effettuare una incisione chirurgica mediale dal processo xifoideo al vicino all&#39;inserzione dei muscoli sternocleidomastoideo. Utilizzare una sega sternale per rimuovere la sporgenza anteriore dallo sterno (sterno) per consentire la dissezione mediale parziale sterno. Utilizzare un taglio tagliare le restanti porzioni della struttura ossea dello sterno. Sezionare il legamento sternale-pericardico e ritrarre il sternum. </li><li> Utilizzare smussa per separare il pericardio dai rivestimenti pleurico. Effettuare una incisione sagittale mediale (3-5 cm) nel pericardio e creare una culla pericardico con quattro punti di sutura nodo quadrato ad ogni angolo (destro, sinistro, superiore e inferiore siti). </li><li> Posizionare un elettrocatetere bipolare temporanea nella regione apicale del ventricolo sinistro e posizionare un unipolare tuffo piombo stimolazione temporanea in appendice atriale sinistra. </li><li> L&#39;eutanasia si ottiene la rimozione del cuore sotto anestesia profonda. </li></ol> 2. Preparazione per il monitoraggio elettrofisiologico <ol><li> Sistema di mappatura cardiaca. <ol><li> Selezionare uno studio AF in un sistema di mappatura cardiaca Collegare i ventricolari epicardici elettrocateteri di stimolazione bipolari e gli elettrocateteri epicardici in appendice atriale con morsetti a coccodrillo alle impostazioni appropriate nel breakout box. Collegare un elettrocardiogramma e di terra i rilievi al sistema. </li></ol></li><li> Oscilloscopio e Grass stimolatore. <ol><li> Collegare ilbipolare di stimolazione ventricolare sinistra e atriale unipolare nella casella breakout ad uno stimolatore Grass che è collegato ad un oscilloscopio per la verifica elettrica. </li></ol></li><li> Programmato elettrofisiologici stimolazione. <ol><li> Fissare i cavi atriale destra e porta ventricolo destro in un pacemaker Posizionare la testa programmatore telemetria sul pacemaker. Selezionare la stimolazione degli elettrodi di stimolazione (PES) di studio e di impostare i parametri per 8v; rimuovere tutti i parametri del paziente. Impostare la durata stimolazione impostato su 8 impulsi a 400 msec (o 300 msec). </li></ol></li></ol> 3. In Situ Studio <ol><li> Periodo refrattario: Studio paradigma. <ol><li> Determinare il periodo atriale efficace refrattario (AERP), il nodo del ventricolo atriale periodo refrattario (AVNERP) e il periodo refrattario effettivo ventricolare (VERP) al basale, e a 30 e 60 minuti dopo la consegna pericardico di composto / farmaco / trattamento di controllo; punti temporali addizionali possono essere aggiunti come desired. </li></ol></li><li> Periodo refrattario: Impostazioni programmatore. <ol><li> Burst indurre il parametro studio PES a 8 passi (400 msec o 300 msec) seguito da un minimo di 300 msec stimolazione. Ridurre il ritmo fino a quando i ventricoli / Atrium (rispettivamente) non riescono a contrarsi. Questo si nota dal rilevamento dei conduttori di stimolazione; determinando così il periodo refrattario relativo. </li></ol></li></ol><img alt="figura 2" src="/files/ftp_upload/52600/52600fig2.jpg" /> Figura 2. EnSiteSystem: AERP, AVNERP e VERP Determinazione <a href="https://www.jove.com/files/ftp_upload/52600/52600fig2large.jpg" target="_blank">Cliccate qui per vedere una versione più grande di questa figura.</a> <ol start="3"><li> Determinazione dei relativi AF Burden: Parametri. <ol><li> Sostenere il cuore dell&#39;animale in AF, dopo 1 minuto, permettono di rimanere in AF per un massimo di 10 min. Per esempio, prima di scioccante gli atri con comandi diretti a 5 joule di interrompere AF. ElICIT induzione AF fino a 10 volte in ogni punto del tempo. Si noti, in questo studio. AF è definito come un ritmo irregolare con assenza dell&#39;onda P. </li></ol></li><li> AF Burden: Erba stimolatore e impostazioni dell&#39;oscilloscopio. <ol><li> Ottimizzare i parametri per lo stimolatore Grass per fornire 4 Hz con una durata dell&#39;impulso 2 sec per l&#39;appendice atriale sinistra (LAA) tramite il cavo di tuffo stimolazione; verificare questo da un oscilloscopio standard. Fornire un singolo impulso alla LAA per indurre AF. </li></ol></li></ol> 4. Cuore espianto e Rianimazione (trapianto Model) <ol><li> Aortica Root cannula. <ol><li> sezionare con cura il tessuto pericardico intorno alla aorta ascendente e rimuovere i pericardium.Suture due punti (2-3 cm di distanza) di 2,0 sutura Ethibond in aorta ascendente e amministrare 30.000 unità di eparina per via endovenosa. </li><li> Posizionare la cannula della radice aortica tra i punti di sutura e fissare l&#39;aorta. Con il sistema di erogazione pressurizzato, rimuovere tegli mandrino a coppia conica e posizionare un morsetto sulla cannula non permettendo per il flusso. </li></ol></li><li> Cardioplegia Preparazione. <ol><li> Somministrare fredda soluzione cardioplegia St. Thomas in aorta ascendente sotto una pressione di 150 mm / Hg tramite una sacca pressurizzata. Fissare un catetere di irrigazione che è collegato al cardioplegia pressurizzato con un 3-way rubinetto sull&#39;estremità distale. Fissare il rubinetto alla cannula della radice aortica, rilasciare un filo costante di cardioplegia attraverso il catetere e fissare alla cannula della radice aortica. </li></ol></li><li> Cross-morsetto. <ol><li> Bloccare la vena cava inferiore con una atraumaticclamp 1-2 cm appena superiori al diaframma. Bloccare l&#39;aorta ascendente con atraumatica angolato campo di 1-2 cm sul aorta ascendente superiore alla cannula della radice aortica. </li></ol></li><li> Cross-morsetto / cardioplegia. <ol><li> Rimuovere la fascetta dalla cannula della radice aortica e lavare la cardioplegia a 150 mm / Hg verso la valvola aortica, chiudendo la valvola aortica e perfusing coronarie. </li><li> Fissare la vena cava superiore e fare una piccola incisione nell&#39;arteria polmonare, in modo da non eccedere pressurizzare cuore. Una volta che il cuore si arresta (asystolic), accise e rimuovere il cuore dal petto e posto in un bagno di freddo tampone Krebs-Henseleit (~ 3-8 ° C). </li></ol></li><li> Rianimazione. <ol><li> Cannulate grossi vasi e preparare il cuore utilizzando metodologie di cuore visibile (3). Una volta che il cuore perfuso raggiunge 37 ± 5 ° C, il ripristino di un ritmo sinusale nativa, offrendo 34 J shock ai ventricoli tramite elettrodi di patch epicardici. </li></ol></li></ol> 5. studio in vitro Paradigma <ol><li> il monitoraggio continuo della funzione cardiaca per 60 minuti dopo rianimazione. Continuamente monitorare ecocardiografia in modalità 2D con asse corto: una vista LV appena sotto la valvola mitrale. </li><li> Calcolare parete ventricolare spessore ed espulsione frazioni ogni 10 min dopo rianimazione (vedi sotto).Prendere campioni dal seno coronarico (1 cc) a -5 min ed ogni 5 minuti durante il periodo di valutazione. </li><li> Monitoraggio. <ol><li> Monitorare l&#39;emodinamica per entrambi i ventricoli destro, tra cui pressioni, flussi e le variazioni di volume e sinistro. </li></ol></li><li> Ecocardiografia: Frazione di eiezione. <ol><li> Posizionare una sonda transtoracica eco direttamente sul cuore, catturando un asse corto metà papillare. Calcolare la frazione di eiezione (EF%) in modalità di lavoro a 4 camere ogni 10 minuti con la seguente equazione: LV Fine diastolica Volume - LV Fine sistolica Volume X 100 Volume / LV Fine diastolica </li></ol></li><li> Ecocardiografia: ventricolo sinistro spessore della parete. <ol><li> Misurare lo spessore della parete ventricolare (cm) da una finestra asse corto metà papillare a 10 min intervalli per una rianimazione dopo un&#39;ora. Misurare quattro angoli del ventricolo sinistro utilizzando uno schermo pinze e fare la media. </li></ol></li><li> Metabolismo miocardico. <ol><li> Posizionare un steeraCatetere ble nel seno coronarico (CS). Esempio 1 cc dal CS 5 minuti prima rianimazione e ogni 5 minuti dopo rianimazione per 1 ora. Testare i campioni per livelli di lattato e glucosio; altri gas del sangue possono anche essere valutati. </li></ol></li></ol>

<ol>
	<li>Richardson, E. S., Rolfes, C., Woo, S. O., Elmquist, W. F., Benditt, D. G., Iaizzo, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+Responses+to+the+Intrapericardial+Delivery+of+Metoprolol:+Target+Delivery+Compared+to+Intravenous+Administration.">Cardiac Responses to the Intrapericardial Delivery of Metoprolol: Target Delivery Compared to Intravenous Administration.</a> J. Cardiovasc. Translational Research. 5 (4), 535-540 (2012).</li><li>Xiao, Y. F., Sigg, D. C., Ujhelyi, M. R., Wilhelm, J. J., Richardson, E. S., Iaizzo, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pericardial+delivery+of+omega-3+fatty+acid:+a+novel+approach+to+reducing+myocardial+infarct+sizes+and+arrhythmias.">Pericardial delivery of omega-3 fatty acid: a novel approach to reducing myocardial infarct sizes and arrhythmias.</a> Am J Physiol Heart Circ Physiol. 294 (5), 2212-2218 (2008).</li><li>Chinchoy, 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=Isolated+four-chamber+working+swine+heart+model.">Isolated four-chamber working swine heart model.</a> Ann Thorac Surg. 70 (5), 1607-1614 (2000).</li><li>Moreno, R., Waxman, S., Rowe, K., Verrier, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrapericardial+beta-adrenergic+blockade+with+esmolol+exerts+a+potent+antitachycardic+effect+without+depressing+contractility.">Intrapericardial beta-adrenergic blockade with esmolol exerts a potent antitachycardic effect without depressing contractility.</a> J Cardiovasc Pharmacol. 36 (6), 722-727 (2000).</li><li>Jansen, B. 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=Intrapericardial+delivery+enhances+cardiac+effects+of+sotalol+and+atenolol.">Intrapericardial delivery enhances cardiac effects of sotalol and atenolol.</a> J Cardiovasc Pharmacol. 44 (1), 50-56 (2004).</li><li>Vereckei, A., Gorski, J. C., Ujhelyi, M., Mehra, R., Zipes, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrapericardial+ibutilide+administration+fails+to+terminate+pacing-induced+sustained+atrial+fibrillation+in+dogs.">Intrapericardial ibutilide administration fails to terminate pacing-induced sustained atrial fibrillation in dogs.</a> Cardiovas Drugs Ther. 18 (4), 269-277 (2004).</li><li>Kumar, K., Nguyen, K., Waxman, S., Nearing, B. D., Wellenius, G. A., Zhao, S. X., Verrier, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Potent+antifibrillatory+effects+of+intrapericardial+nitroglycerin+in+the+ischemic+porcine+heart.">Potent antifibrillatory effects of intrapericardial nitroglycerin in the ischemic porcine heart.</a> J Am Coll Cardiol. 41 (10), 1831-1837 (2003).</li><li>Fei, L., Baron, A. D., Henry, D. P., Zipes, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrapericardial+delivery+of+L-arginine+reduces+the+increased+severity+of+ventricular+arrhythmias+during+sympathetic+stimulation+in+dogs+with+acute+coronary+occlusion:+nitric+oxide+modulates+sympathetic+effects+on+ventricular+electrophysiological+properties.">Intrapericardial delivery of L-arginine reduces the increased severity of ventricular arrhythmias during sympathetic stimulation in dogs with acute coronary occlusion: nitric oxide modulates sympathetic effects on ventricular electrophysiological properties.</a> Circulation. 96 (11), 4044-4049 (1997).</li><li>Ayers, G. M., Rho, T. H., Ben-David, J., Besch, H. R., Zipes, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amiodarone+instilled+into+the+canine+pericardial+sac+migrates+transmurally+to+produce+electrophysiologic+effects+and+suppress+atrial+fibrillation.">Amiodarone instilled into the canine pericardial sac migrates transmurally to produce electrophysiologic effects and suppress atrial fibrillation.</a> J Cardiovasc Electrophysiol. 7 (8), 713-721 (1996).</li><li>Darsinos, J. T., Karli, J. N., Samouilidou, E. C., Krumbholz, B., Pistevos, A. C., Levis, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distribution+of+amiodarone+in+heart+tissues+following+intrapericardial+administration.">Distribution of amiodarone in heart tissues following intrapericardial administration.</a> Int. J. Clin. Pharacol Ther. 37 (6), 301-306 (1999).</li><li>Ujhelyi, M. R., Hadsall, K. Z., Euler, D. E., Mehra, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrapericardial+therapeutics:+a+pharmacodynamic+and+pharmacokinetic+comparison+between+pericardial+and+intravenous+procainamide+delivery.">Intrapericardial therapeutics: a pharmacodynamic and pharmacokinetic comparison between pericardial and intravenous procainamide delivery.</a> J Cardiovasc Electrophysiol. 13 (6), 605-611 (2002).</li></ol>

The authors have nothing to disclose

Qui, abbiamo dimostrato un approccio unico per testare l&#39;efficacia potenziale di composti consegnati bersaglio nello spazio pericardico. Questo paradigma studio può essere utilizzato per testare mercato attuale rilasciato prodotti farmaceutici o composti sperimentali, fornendo così applicazioni traslazionali scalo a varie situazioni cliniche. All&#39;interno di questa strategia di trattamento ci sono due principali applicazioni cliniche per la distribuzione di prodotti farmaceutici allo spazio pericardico: 1) a cu...

Attualmente in procedure a cuore aperto, i medici utilizzano agenti di trattamento antiaritmici e altre sistemica. Tuttavia, questo può essere problematico per molti pazienti, soprattutto quelli che sono già clinicamente compromessi. Ad esempio, i trattamenti per via endovenosa può causare cadute sistemici della pressione sanguigna o disfunzione renale; inoltre, possono creare problemi di gestione di anestesia e / o altri effetti collaterali a lungo termine. Qui abbiamo creato un modello per testare l&#39;efficacia di somministrazione di agenti farmacologici nello spazio pericardico. Ad esempio, questo approccio può essere utilizzato per testare farmaci antiaritmici, studiando composti che potrebbero aumentare la funzione cardiaca e / o promuovere il recupero del miocardio dopo procedure chirurgiche. Ci sono stati osservati benefici alla consegna bersaglio di trattamenti nello spazio pericardico contro somministrazione endovenosa: per esempio, il nostro laboratorio ha dimostrato che la consegna localizzata di antiarfarmaci ritmici, come metoprololo, è protettivo contro l&#39;incidenza di aritmie minimizzando riduzioni della pressione sanguigna 1. Questa strategia di fornitura di destinazione offre anche la possibilità per l&#39;amministrazione di concentrazioni focali più elevate riducendo al minimo i livelli sistemici. Ad esempio, alti livelli di concentrazioni endovenosa forniti di acidi grassi possono provocare emolisi, ma la consegna pericardico minimizza questa preoccupazione 2. Questo studio paradigma consiste di tre obiettivi principali per determinare l&#39;efficacia del pericardio consegnato composti: 1) nella determinazione del situ dei periodi refrattari del nodo ventricolare atriale, atri e ventricoli, prima del trattamento e post trattamento 30 e 60 min; 2) la relativa in situ onere AF prima del trattamento e 30 e 60 min dopo trattamento (timepoints supplementari sono stati spesso aggiunti) 3) analisi funzionale del cuore dopo che è stato rianimato 3 incLuding monitoraggio emodinamico, la frequenza cardiaca, il metabolismo del cuore (lattato e glucosio) campionata dal seno coronarico, frazione di eiezione (EF%) e lo spessore della parete ventricolare (cm) monitorato ogni 10 min dopo rianimazione Questo modello strategia di trattamento ci ha permesso di osservare gli effetti del agenti farmacologici che possono diminuire l&#39;incidenza di aritmie cardiache e / o danno ischemico, durante e dopo l&#39;intervento chirurgico a cuore aperto o al trapianto.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>SelectSecure&#174; 3830 lead</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>Pacing Lead&#160;</td>
		</tr>
		<tr>
			<td>C304 Deflectable Catheter&#160;</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>Steerable catheter for placing leads&#160;</td>
		</tr>
		<tr>
			<td>SelectSecure&#174; 3830 lead</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>active fixation pacing leads&#160;</td>
		</tr>
		<tr>
			<td>Grass S48 Stimulator</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>Electrical Stimulator&#160;</td>
		</tr>
		<tr>
			<td>Premium 6500 Unipolar Pacing&#160;</td>
			<td></td>
			<td>N/A</td>
			<td>Plunge pacing lead for LAA</td>
		</tr>
		<tr>
			<td>EnSite&#8482; Cardiac Mapping</td>
			<td></td>
			<td>N/A</td>
			<td>Electrophysiology mapping system</td>
		</tr>
		<tr>
			<td>CareLink Programer 2092</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>programmer for pacing leads</td>
		</tr>
		<tr>
			<td>GEM II &#174; pacemaker&#160;</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>pacemaker can&#160;</td>
		</tr>
		<tr>
			<td>DLP &#174; Aortic Root Cannula</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>aortic root cannula for transplant&#160;</td>
		</tr>
		<tr>
			<td>C-Arm Fluoroscopy</td>
			<td>Ziehm&#160;</td>
			<td>N/A</td>
			<td>fluoroscopic imaging&#160;</td>
		</tr>
		<tr>
			<td>Oscilliscope</td>
			<td>Tektronix&#160;</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>11F Hemostasis introducer</td>
			<td>SafeSheath</td>
			<td>N/A</td>
			<td>Hemostasis introducers</td>
		</tr>
		<tr>
			<td>Swan-Ganz Catheter 8.0F</td>
			<td>ICU Medical&#160;</td>
			<td>N/A</td>
			<td>thermal dilution catheter&#160;</td>
		</tr>
		<tr>
			<td>Venogram balloon&#160;</td>
			<td>Oscor</td>
			<td>N/A</td>
			<td>pressure monitoring&#160;</td>
		</tr>
		<tr>
			<td>Ultraview SL</td>
			<td>Spacelabs</td>
			<td>N/A</td>
			<td>EKG and blood pressure&#160;</td>
		</tr>
		<tr>
			<td>s/5 Avance</td>
			<td>General Electric</td>
			<td>N/A</td>
			<td>Anesthesia machine</td>
		</tr>
		<tr>
			<td>Atrial 6492 &#8211; Unipolar Temporary Atrial Pacing Lead</td>
			<td>Medtronic</td>
			<td>N/A</td>
			<td>temporary pacing lead&#160;</td>
		</tr>
		<tr>
			<td>VIVID i</td>
			<td>General Electric</td>
			<td></td>
			<td>2D electrocardiography unit&#160;</td>
		</tr>
	</tbody>
</table>

testing the efficacy of pharmacological agents in a pericardial target delivery model in the swine

Fino ad oggi, molti agenti farmacologici usati per trattare o prevenire le aritmie nei casi a cuore aperto creare effetti collaterali sistemici indesiderati. Ad esempio, i farmaci antiaritmici somministrati per via endovenosa in grado di produrre gocce di pressione sistemica nel paziente cardiaco già compromesso. Durante l&#39;esecuzione delle procedure a cuore aperto, i chirurghi spesso creare un piccolo porto o formare una culla pericardica per creare campi adatti per il funzionamento. Questo accesso produce opportunità per obiettivo la consegna farmacologica (agenti di precondizionamento antiaritmici o ischemiche) direttamente al tessuto miocardico senza effetti collaterali indesiderati. Abbiamo sviluppato un modello di suini per testare agenti farmacologici per la consegna di destinazione all&#39;interno del fluido pericardico. Mentre completamente anestetizzato, ogni animale è stato strumentato con un catetere di Swan-Ganz e cateteri pressione ventricolo sinistro e destro, e elettrocateteri di stimolazione sono stati collocati in appendice atriale destra e il dirittoventricolo. Un sternotomia mediana è stata poi eseguita e una culla accesso pericardico è stato creato; un cavo tuffo di stimolazione è stato posto in dell&#39;atrio sinistro e un elettrocatetere bipolare è stato collocato nel ventricolo sinistro. Utilizzando un programmatore e un sistema di mappatura cardiaca, il periodo refrattario del nodo atrioventricolare (AVN), atri e ventricoli è stata determinata. Inoltre, la fibrillazione atriale (AF) induzione è stata prodotta utilizzando uno stimolatore Grass e tempo AF è stato osservato. Queste misurazioni sono state effettuate prima del trattamento, nonché 30 minuti e 60 minuti dopo il trattamento pericardico. Ulteriori punti di tempo sono stati aggiunti per gli studi selezionati. Il cuore è stato poi cardiopleged e rianimato in una modalità di lavoro di quattro camera. Le misure di pressione e la funzione sono stati registrati per 1 ora dopo la rianimazione. Questo modello strategia di trattamento ci ha permesso di osservare gli effetti di agenti farmacologici che possono diminuire l&#39;incidenza di aritmie cardiache e / o danno ischemico, durante e AFter chirurgia a cuore aperto.

Questi risultati sono caratteristici dei dati che possono essere raccolti utilizzando questo modello di distribuzione bersaglio di agenti farmacologici in suina. Questi dati hanno dimostrato notevoli aumenti in questi ventricolo efficaci periodi refrattari (Verp) a seguito di una infusione di DHA in situ. Inoltre, i dati stabilisce un aumento della pressione ventricolare sinistra di DHA rispetto al controllo in vitro. La pressione LV nei cuori DHA trattati erano significativamente più alti rispetto al...

Watch this Scientific Journal Video about Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine at JoVE.com

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

We have developed a swine model for the target delivery of pharmacological agents within the pericardial space/fluid. Using this approach, the relative benefits of administered agents on induced atrial fibrillation, relative refractory periods and/or ischemic protection can be investigated.

Testare l&#39;efficacia di agenti farmacologici in un pericardica target Delivery Model nel suina

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, ...

testing-efficacy-pharmacological-agents-pericardial-target-delivery

Research

Education

JoVE Core

JoVE Journal

Pharmacology

Medicine

Unit 1

Cardiovascular Drugs: Antiarrhythmic and Heart Failure Drugs

SCIENTISTS IN ACTION

8.2K Views.  University of Minnesota. We have developed a swine model for the target delivery of pharmacological agents within the pericardial space/fluid. Using this approach, the relative benefits of administered agents on induced atrial fibrillation, relative refractory periods and/or ischemic protection can be investigated. 

Video: Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

Making Sense of Listening: The IMAP Test Battery

The ability to hear is only the first step towards making sense of the range of information contained in an auditory signal. Of equal importance are the abilities to extract and use the information encoded in the auditory signal. We refer to these as listening skills (or auditory processing AP). Deficits in these skills are associated with delayed language and literacy development, though the nature of the relevant deficits and their causal connection with these delays is hotly debated.
When a child is referred to a health professional with normal hearing and unexplained difficulties in listening, or associated delays in language or literacy development, they should ideally be assessed with a combination of psychoacoustic (AP) tests, suitable for children and for use in a clinic, together with cognitive tests to measure attention, working memory, IQ, and language skills. Such a detailed examination needs to be relatively short and within the technical capability of any suitably qualified professional. Current tests for the presence of AP deficits tend to be poorly constructed and inadequately validated within the normal population. They have little or no reference to the presenting symptoms of the child, and typically include a linguistic component. Poor performance may thus reflect problems with language rather than with AP. To assist in the assessment of children with listening difficulties, pediatric audiologists need a single, standardized child-appropriate test battery based on the use of language-free stimuli.
We present the IMAP test battery which was developed at the MRC Institute of Hearing Research to supplement tests currently used to investigate cases of suspected AP deficits. IMAP assesses a range of relevant auditory and cognitive skills and takes about one hour to complete. It has been standardized in 1500 normally-hearing children from across the UK, aged 6-11 years. Since its development, it has been successfully used in a number of large scale studies both in the UK and the USA. IMAP provides measures for separating out sensory from cognitive contributions to hearing. It further limits confounds due to procedural effects by presenting tests in a child-friendly game-format. Stimulus-generation, management of test protocols and control of test presentation is mediated by the IHR-STAR software platform. This provides a standardized methodology for a range of applications and ensures replicable procedures across testers. IHR-STAR provides a flexible, user-programmable environment that currently has additional applications for hearing screening, mapping cochlear implant electrodes, and academic research or teaching.

A test battery (IMAP) for performing an in-depth assessment of auditory and cognitive abilities contributing to listening skills is described. It is quick to administer, child-friendly and free from linguistic confounds. Stimulus generation and protocol management are controlled via a software platform (IHR-STAR) to ensure replicable procedures.

Making Sense di Ascolto: La batteria di test IMAP

The ability to hear is only the first step towards making sense of the range of information contained in an auditory signal. Of equal importance are the ...

Ricerca

Medicina

A Swine Model of Neonatal Asphyxia

Annually more than 1 million neonates die worldwide as related to asphyxia. Asphyxiated neonates commonly have multi-organ failure including hypotension, perfusion deficit, hypoxic-ischemic encephalopathy, pulmonary hypertension, vasculopathic enterocolitis, renal failure and thrombo-embolic complications. Animal models are developed to help us understand the patho-physiology and pharmacology of neonatal asphyxia. In comparison to rodents and newborn lambs, the newborn piglet has been proven to be a valuable model. The newborn piglet has several advantages including similar development as that of 36-38 weeks human fetus with comparable body systems, large body size (&tilde;1.5-2 kg at birth) that allows the instrumentation and monitoring of the animal and controls the confounding variables of hypoxia and hemodynamic derangements.
We here describe an experimental protocol to simulate neonatal asphyxia and allow us to examine the systemic and regional hemodynamic changes during the asphyxiating and reoxygenation process as well as the respective effects of interventions. Further, the model has the advantage of studying multi-organ failure or dysfunction simultaneously and the interaction with various body systems. The experimental model is a non-survival procedure that involves the surgical instrumentation of newborn piglets (1-3 day-old and 1.5-2.5 kg weight, mixed breed) to allow the establishment of mechanical ventilation, vascular (arterial and central venous) access and the placement of catheters and flow probes (Transonic Inc.) for the continuously monitoring of intra-vascular pressure and blood flow across different arteries including main pulmonary, common carotid, superior mesenteric and left renal arteries. Using these surgically instrumented piglets, after stabilization for 30-60 minutes as defined by Z&lt;10% variation in hemodynamic parameters and normal blood gases, we commence an experimental protocol of severe hypoxemia which is induced via normocapnic alveolar hypoxia. The piglet is ventilated with 10-15% oxygen by increasing the inhaled concentration of nitrogen gas for 2h, aiming for arterial oxygen saturations of 30-40%. This degree of hypoxemia will produce clinical asphyxia with severe metabolic acidosis, systemic hypotension and cardiogenic shock with hypoperfusion to vital organs. The hypoxia is followed by reoxygenation with 100% oxygen for 0.5h and then 21% oxygen for 3.5h. Pharmacologic interventions can be introduced in due course and their effects investigated in a blinded, block-randomized fashion.

Large animal models have good translational values in the examination of physiology and pharmacology of neonatal asphyxia. Using newborn piglets, we develop an experimental protocol to simulate neonatal asphyxia which has advantages of studying the systemic and regional hemodynamics, oxygen transport with biochemical and pathologic pathways and correlations.

Un modello di asfissia neonatale suina

Annually more than 1 million neonates die worldwide as related to asphyxia. Asphyxiated neonates commonly have multi-organ failure including hypotension, ...

Clinical Testing and Spinal Cord Removal in a Mouse Model for Amyotrophic Lateral Sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in progressive degeneration of motoneurons. Peak of onset is around 60 years for the sporadic disease and around 50 years for the familial disease. Due to its progressive course, 50% of the patients die within 30 months of symptom onset. In order to evaluate novel treatment options for this disease, genetic mouse models of ALS have been generated based on human familial mutations in the SOD gene, such as the SOD1 (G93A) mutation. Most important aspects that have to be evaluated in the model are overall survival, clinical course and motor function. Here, we demonstrate the clinical evaluation, show the conduction of two behavioural motor tests and provide quantitative scoring systems for all parameters. Because an in depth analysis of the ALS mouse model usually requires an immunohistochemical examination of the spinal cord, we demonstrate its preparation in detail applying the dorsal laminectomy method. Exemplary histological findings are demonstrated. The comprehensive application of the depicted examination methods in studies on the mouse model of ALS will enable the researcher to reliably test future therapeutic options which can provide a basis for later human clinical trials.

Clinical Testing and Spinal Cord Removal in a Mouse Model for Amyotrophic Lateral Sclerosis ALS

A mouse model for amyotrophic lateral sclerosis (ALS) is examined clinically and behaviorally. As a prerequisite for an accompanying immunohistological analysis the preparation of the spinal cord is depicted in detail.

Test clinici e la rimozione del midollo spinale in un modello murino di sclerosi laterale amiotrofica (SLA)

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in progressive degeneration of motoneurons. Peak of onset is around 60 ...

Excitotoxic Stimulation of Brain Microslices as an In vitro Model of Stroke

Examining molecular mechanisms involved in neuropathological conditions, such as ischemic stroke, can be difficult when using whole animal systems. As such, primary or &#39;neuronal-like&#39; cell culture systems are commonly utilized. While&#160;these systems are relatively easy to work with, and are useful model systems in which various functional outcomes (such as cell death) can be readily quantified, the examined outcomes and pathways in cultured immature neurons (such as excitotoxicity-mediated cell death pathways) are not necessarily the same as those observed in mature brain, or in intact tissue. Therefore, there is the need to develop models in which cellular mechanisms in mature neural tissue can be examined. We have developed an in vitro technique that can be used to investigate a variety of molecular pathways in intact nervous tissue. The technique described herein utilizes rat cortical tissue, but this technique can be adapted to use tissue from a variety of species (such as mouse, rabbit, guinea pig, and chicken) or brain regions (for example, hippocampus, striatum, etc.). Additionally, a variety of stimulations/treatments can be used (for example, excitotoxic, administration of inhibitors, etc.). In conclusion, the brain slice model described herein can be used to examine a variety of molecular mechanisms involved in excitotoxicity-mediated brain injury.

Excitotoxic Stimulation of Brain Microslices as an In vitro Model of Stroke

We have developed a brain slice model which can be used to examine molecular mechanisms involved in excitotoxicity-mediated brain injury.&#160;This technique generates viable mature brain tissue and reduces animal numbers required for experimentation, whilst keeping the neuronal circuitry, cellular interactions, and postsynaptic compartments partly intact.

Eccitotossica stimolazione del cervello Microslices come<em&gt; In vitro</em&gt; Modello di Corsa

Examining molecular mechanisms involved in neuropathological conditions, such as ischemic stroke, can be difficult when using whole animal systems. As ...

Surgical Placement of Catheters for Long-term Cardiovascular Exercise Testing in Swine

This protocol describes the surgical procedure to chronically instrument swine and the procedure to exercise swine on a motor-driven treadmill. Early cardiopulmonary dysfunction is difficult to diagnose, particularly in animal models, as cardiopulmonary function is often measured invasively, requiring anesthesia. As many anesthetic agents are cardiodepressive, subtle changes in cardiovascular function may be masked. In contrast, chronic instrumentation allows for measurement of cardiopulmonary function in the awake state, so that measurements can be obtained under quiet resting conditions, without the effects of anesthesia and acute surgical trauma. Furthermore, when animals are properly trained, measurements can also be obtained during graded treadmill exercise.
Flow probes are placed around the aorta or pulmonary artery for measurement of cardiac output and around the left anterior descending coronary artery for measurement of coronary blood flow. Fluid-filled catheters are implanted in the aorta, pulmonary artery, left atrium, left ventricle and right ventricle for pressure measurement and blood sampling. In addition, a 20 G&#160;catheter is positioned in the anterior interventricular vein to allow coronary venous blood sampling.
After a week of recovery, swine are placed on a motor-driven treadmill, the catheters are connected to pressure and flow meters, and swine are subjected to a five-stage progressive exercise protocol, with each stage lasting 3 min. Hemodynamic signals are continuously recorded and blood samples are taken during the last 30 sec of each exercise stage.
The major advantage of studying chronically instrumented animals is that it allows serial assessment of cardiopulmonary function, not only at rest but also during physical stress such as exercise. Moreover, cardiopulmonary function can be assessed repeatedly during disease development and during chronic treatment, thereby increasing statistical power and hence limiting the number of animals required for a study.

Here we present a protocol to assess cardiopulmonary function in awake swine, at rest and during graded treadmill exercise. Chronic instrumentation allows for repeated hemodynamic measurements uninfluenced by cardiodepressive anesthetic agents.

Posizionamento chirurgico di cateteri per durata Esercizio cardiovascolare test in Swine

This protocol describes the surgical procedure to chronically instrument swine and the procedure to exercise swine on a motor-driven treadmill. Early ...

Hemocompatibility Testing of Blood-Contacting Implants in a Flow Loop Model Mimicking Human Blood Flow

The growing use of medical devices (e.g., vascular grafts, stents, and cardiac catheters) for temporary or permanent purposes that remain in the body&#39;s circulatory system demands a reliable and multiparametric approach that evaluates the possible hematologic complications caused by these devices (i.e., activation and destruction of blood components). Comprehensive in vitro hemocompatibility testing of blood-contacting implants is the first step towards successful in vivo implementation. Therefore, extensive analysis according to the International Organization for Standardization 10993-4 (ISO 10993-4) is mandatory prior to clinical application. The presented flow loop describes a sensitive model to analyze the hemostatic performance of stents (in this case, neurovascular) and reveal adverse effects. The use of fresh human whole blood and gentle blood sampling are essential to avoid the preactivation of blood. The blood is perfused through a heparinized tubing containing the test specimen by using a peristaltic pump at a rate of 150 mL/min at 37 &#176;C for 60 min. Before and after perfusion, hematologic markers (i.e., blood cell count, hemoglobin, hematocrit, and plasmatic markers) indicating the activation of leukocytes (polymorphonuclear [PMN]-elastase), platelets (&#946;-thromboglobulin [&#946;-TG]), the coagulation system (thombin-antithrombin III [TAT]), and the complement cascade (SC5b-9) are analyzed. In conclusion, we present an essential and reliable model for extensive hemocompatibility testing of stents and other blood-contacting devices prior to clinical application.

This protocol describes a comprehensive hemocompatibility evaluation of blood-contacting devices using laser-cut neurovascular implants. A flow loop model with fresh, heparinized human blood is applied to mimic blood flow. After perfusion, various hematologic markers are analyzed and compared to the values gained directly after blood collection for hemocompatibility evaluation of the tested devices.

Test di emocompatibilità degli impianti che si contattono con il sangue in un modello di flusso a ciclo continuo che imita il flusso sanguigno umano

The growing use of medical devices (e.g., vascular grafts, stents, and cardiac catheters) for temporary or permanent purposes that remain in the ...

Standardized Model of Ventricular Fibrillation and Advanced Cardiac Life Support in Swine

Cardiopulmonary resuscitation after cardiac arrest, independent of its origin, is a regularly encountered medical emergency in hospitals as well as preclinical settings. Prospective randomized trials in human subjects are difficult to design and ethically ambiguous, which results in a lack of evidence-based therapies. The model presented in this report represents one of the most common causes of cardiac arrests, ventricular fibrillation, in a standardized setting in a large animal model. This allows for reproducible observations and various therapeutic interventions under clinically accurate conditions, hence facilitating the generation of better evidence and eventually the potential for improved medical treatment.

Cardiopulmonary resuscitation and defibrillation are the only effective therapeutic options during cardiac arrest caused by ventricular fibrillation. This model presents a standardized regimen to induce, assess, and treat this physiological state in a porcine model, thus providing a clinical approach with various opportunities for data collection and analysis.

Modello standardizzato di fibrillazione ventricolare e supporto avanzato per la vita cardiaca in suina

Cardiopulmonary resuscitation after cardiac arrest, independent of its origin, is a regularly encountered medical emergency in hospitals as well as ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

Somministrazione intratracheale della formulazione di polvere secca nei topi

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...

Large Animal Model for Evaluating the Efficacy of the Gene Therapy in Ischemic Heart

Coronary artery disease is one of the significant causes of mortality and morbidity worldwide. Despite the progression of current therapeutics, a considerable proportion of coronary artery disease patients remain symptomatic. Gene therapy-mediated therapeutic angiogenesis offers a novel therapeutic method for improving myocardial perfusion and relieving symptoms. Gene therapy with different angiogenic factors has been studied in few clinical trials. Due to the novelty of the method, the progress of myocardial gene therapy is a continuous path from bench to bedside. Therefore, large animal models are needed for evaluating the safety and efficacy. The more the large animal model identifies the original disease and the endpoints used in clinics, the more predictable outcomes are from clinical trials. Here, we introduce a large animal model for evaluating the efficacy of the gene therapy in the ischemic porcine heart. We use clinically relevant imaging methods such as ultrasound imaging and 15H2O-PET. For targeting the gene transfers into the desired area, electroanatomical mapping is used. The aim of this method is: (1) to mimic chronic coronary artery disease, (2) to induce therapeutic angiogenesis at hypoxic areas of the heart, and (3) to evaluate the safety and efficacy of the gene therapy by using relevant endpoints.

Myocardial gene therapy for ischemic heart disease holds great promise for future therapeutics. Here, we introduce a large animal model for evaluating the efficacy of gene therapy in the ischemic heart.

Modello animale di grandi dimensioni per valutare l'efficacia della terapia genica nel cuore ischemico

Coronary artery disease is one of the significant causes of mortality and morbidity worldwide. Despite the progression of current therapeutics, a ...

Endotracheal Intubation Using a Flexible Intubation Endoscope as a Standardized Model for Safe Airway Management in Swine

Endotracheal intubation is often a basic requirement for translational research in porcine models for various interventions that require a secured airway or high ventilation pressures. Endotracheal intubation is a challenging skill,&#160;requiring a minimum number of successful endotracheal intubations to achieve a high success rate under optimal conditions, which is often unachievable for non-anaesthesiology researchers. Due to the specific porcine airway anatomy, a difficult airway can usually be assumed. The impossibility of establishing a secure airway can result in injury, adverse events, or death of the laboratory animal. Using a prospective, randomized, controlled evaluation approach, it has been shown that fiberoptic-assisted endotracheal intubation takes longer but has a higher first-pass success rate than conventional intubation without causing clinically relevant drops in oxygen saturation. This model presents a standardized regimen for endoscopically guided endotracheal intubation, providing a secured airway, especially for researchers who are inexperienced in the technique of endotracheal intubation via direct laryngoscopy. This procedure is expected to minimize animal suffering and unnecessary animal losses.

The use of pigs in research has increased in recent years. Nevertheless, pigs are characterized by difficult airway anatomy. By demonstrating how to perform endoscopically guided endotracheal intubation, the present protocol aims to further increase laboratory animals' safety to avoid animal suffering and unnecessary death.

Intubazione endotracheale utilizzando un endoscopio per intubazione flessibile come modello standardizzato per la gestione sicura delle vie aeree nei suini

Endotracheal intubation is often a basic requirement for translational research in porcine models for various interventions that require a secured airway ...