This work was supported by Onderzoekstoelagen grant OT/13/090 of the KU Leuven and by grant G0A3114N of the FWO-Vlaanderen.

HINWEIS: Alle in diesem Abschnitt beschriebenen experimentellen Verfahren wurden von der Institutional Animal Care und Forschung Beirat der Katholieke Universiteit Leuven genehmigt (Projekt: 154/2013-B De Geest). 1. Ständige Ligation des linken vorderen absteigenden Koronararterie <ol><li> Anesthetize die Maus durch intraperitoneale Verabreichung von 40 mg / kg bis 70 mg / kg Natriumpentobarbital. Stellen Sie sicher, die Maus an ihre richtige Ebene der Anästhesie, wenn es nicht mehr einen festen Zehe Prise reagiert. Überprüfen Sie stets die ordnungsgemäße Betäubung auf diese Weise vor jedem chirurgischen Eingriff oder Intervention. Verwenden Sie Schmieraugensalbe zur Trockenheit der Hornhaut während der Narkose zu verhindern. Bereitzustellen präoperative Analgesie 2-4 h vor dem Start des Verfahrens (Buprenorphin 0,05 mg / kg SQ). <ol><li> Bewerben konsequente aseptische Technik bei Überleben Chirurgie. Umsetzung von Verfahren, die zu einem maximal möglichen Ausmaß mikrobieller con hemmenVerschmutzung, so dass signifikante Infektion oder Eiterung nicht auftritt. Diese Verfahren umfassen die Verwendung von sterilen Instrumenten und sterilen Materialien, Desinfektion der OP-Bereich, und die Entfernung von Fell / Haar über der Operationsstelle und Desinfektion dieser Website. </li></ol></li><li> Intubieren Sie die Maus mit einem selbst zubereiteten abgestumpft 20-Gauge-Nadel. <ol><li> Sie mit der Maus in Rückenlage mit Überstreckung des Kopfes. <ol><li> Stellen Sie das Licht auf den Halsbereich. Heben Sie die Zunge mit einer stumpfen Pinzette. Der Eingang des Kehlkopfes ist deutlich zu erkennen. </li><li> Übergeben Sie die stumpfe Nadel durch den Kehlkopf in die Luftröhre unter direkter Sicht. Beurteilen Sie korrekte Intubation, indem Sie die Maus an das Beatmungsgerät (Schlagvolumen in ul: 3 x Körpergewicht (g) + 155; Frequenz: 120 Hübe pro Minute). </li></ol></li><li> Alternativ zu verbessern Visualisierung der Intubation, indem Sie zuerst sorgfältig Freilegung der Luftröhre. <ol><li> Machen Sie eine 5 mm Mitte der Halsschnitt und einfahrenMuskelgewebe knapp oberhalb der Luftröhre. </li><li> Führen Sie die Intubation mit einem OP-Stereomikroskop für die direkte Visualisierung der Luftröhre. Heben Sie die Zunge und geben Sie den selbst zubereiteten abgestumpft 20-Gauge-Nadel in die Luftröhre. Bestätigen der ordnungsgemäßen Intubation, indem Sie die Maus an das Beatmungsgerät (Schlagvolumen in ul: 3 x Körpergewicht (g) + 155; Frequenz: 120 Hübe pro Minute). </li></ol></li></ol></li><li> Halten Sie die Maus in Rückenlage und fixieren Sie die Maus mit Klebeband. Führen der Operation auf einem Heizkissen zu Unterkühlung zu verhindern. <ol><li> Rasur und desinfizieren Sie die Haut mit Betadine. Darauf achten, dass der linke Hinterbein kreuzt die rechte Hintergliedmaße, um eine bessere Sicht auf die linke Herzkammer während der Operation zu erhalten. </li></ol></li><li> Machen Sie einen kleinen Querhautschnitt bis zum Brustbein und trennen Sie die darunter liegende Haut und Muskeln. </li><li> Ziehen Sie abgesehen von der m. pectoralis minor und m. pectoralis major mit einem 5-0 Seidennaht. </li><li> Machen Sie ein incision im dritten Zwischenrippenraum, indem Sie einen stumpfen Pinzette. </li><li> Bewegen Sie den pincet unter den Zwischenrippenmuskeln von lateral nach medial, bis das Brustbein erreicht ist. Punktion der Brustwand, indem Sie den pincet von innen auf die Haut. Füllen Sie das Thorakotomie durch vorsichtiges Schneiden der Zwischenrippenmuskel direkt über dem pincet mit einer kleinen Schere. Mit dieser Technik können Punktion der Lunge zu verhindern. </li><li> Bringe einen Schwamm in 0,9% NaCl eingetaucht in den Hohlraum, um die Lungen zu schützen. Einführen eines Wundspreizer (Brust Retraktor) in den Interkostalraum, um die Exposition der linken Seite des Herzens zu erhalten. Ab jetzt der linke Vorhof, den linken Ventrikel und die linke vordere absteigende Koronar-Arterie unter dem Stereomikroskop sichtbar. </li><li> Durchführen einer Unterbindung der linken vorderen absteigenden Koronararterie mit einem einzigen 6-0 Prolene Ligatur etwa 1 mm unter der Spitze des linken Atriums. Dies ist distal von der ersten Diagonalzweig. HINWEIS: Alternativ 7-0 (0.05 Mm Durchmesser) oder 8-0 Fäden (0,04 mm Durchmesser) verwendet werden können. Die Nadel ist ein C-1 13 mm 3/8 Kreis Nadel mit abgeschrägter Spitze. Erfolgreiche Ligation des linken vorderen absteigenden Koronararterie induziert sofortige Entfärbung, was zu einem blasserscheine Myokard in dem betroffenen Gebiet. </li><li> Entfernen Sie die Wundspreizer (Brust Aufroller). <ol><li> Platzieren Sie drei 6-0 Ti-Cron Nähte auf der Zwischenrippenraum. Vor dem Anziehen der Fäden, entfernen Sie den Schwamm aus der Brusthöhle und wieder auszubreiten die Lunge durch die Blockierung der Abfluss von dem Beatmungsgerät. Auf diese Weise verbinden die Lungen mit der Pleura parietalis. </li><li> Anschließend eng ziehen die Fäden und wiederholen Wiederausdehnung durch Drücken auf der Brust. Bestätigen den erfolgreichen Abschluss des Thorax unter Verwendung einer kleinen Menge an Salzlösung (keine Luftblasen, wenn Druck auf die Brust zu sehen). </li><li> Schauen Sie durch den Zwischenrippenmuskel, um normale Ausdehnung der Lunge zu bestätigen. Positionieren Sie die beiden Brustmuskeln, als dienzusätzliche Barriere für die Verhinderung eines Pneumothorax. </li></ol></li><li> Schließen Sie die Haut mit 5-0 Seidennahtmaterial. </li><li> Trennen Sie die Maus vom Beatmungsgerät und eine Wiederherstellung auf dem Heizkissen. Sie ein Tier nicht unbeaufsichtigt lassen, bis er wieder zu sich kam, um ausreichende Brustlage zu halten. Sie ein Tier, das der Operation an die Firma von anderen Tieren unterzogen wurde, bis vollständig erholt nicht zurück. </li><li> Konsequent bieten postoperativen Analgesie (Buprenorphin 0,05 mg / kg SQ BID für mindestens 48 Stunden nach der Operation). </li></ol> 2. In-vivo-invasive hämodynamische Messungen an der Maus <ol><li> Vor dem Eingriff Tauchen Sie das 1.0 Französisch Millar Druckkatheter in sterilem Wasser bei 37 ° C für mindestens 30 Minuten, um die Signaldrift zu minimieren. Elektronisch des Drucksensors bei 0 mm Hg und 100 mm Hg und Aufzeichnungsdaten bei 2.000 Hz kalibrieren. </li><li> Führen Anästhesie durch intraperitoneale Verabreichung von 1,4 g / kg Urethan. Überprüfen Sie, obdie Maus an ihre richtige Ebene der Anästhesie, wenn es nicht mehr einen festen Zehe Prise reagiert. </li><li> Setzen Sie den narkotisierten Maus in Rückenlage. Sichern Sie ihre Gliedmaßen mit Klebeband. Pflegen Sie die Körpertemperatur mit einem Heizkissen und mit einem rektale Sonde überwachen. Rasieren Sie den Halsbereich und einen Mittellinienschnitt im Halsbereich, um die Schilddrüse aus. </li><li> Befestigen Sie den Ausschnitt mit verbogenen Nadeln. </li><li> Ziehen Sie abgesehen von der Speicheldrüse und setzen die rechte Arteria carotis communis. Der Vagusnerv, der einen weißen Faden ähnelt, liegt entlang der Arterie. Vorsichtig die Halsschlagader von den Vagusnerv Verwendung eines gebogenen Pinzette. </li><li> Übergeben einer gekrümmten Pinzette unter der rechten gemeinsamen Halsschlagader, um sie von anderen Geweben abzutrennen. Entfernen Bindegewebe um die Arterie. </li><li> Führen Sie zwei 6-0 Seiden Drähte unter der rechten Halsschlagader. Machen Sie einen festen Knoten auf der obersten Draht, der in Richtung des Kopfes, in der Nähe platziert ist, und befestigen Sie mit einem kocher (distalen Verschlussligation). Übergeben Sie die proximal Draht zweimal von links nach rechts und befestigen Sie sie mit 2 Kochers (proximal nichtokklusiven Draht). </li><li> Halten Sie die Halsschlagader feucht durch Fallen steriler 0,9% NaCl. Trocknen Sie die überschüssige Flüssigkeit mit Wattestäbchen. </li><li> Einen Einschnitt in die rechte Arteria carotis communis mit einer 26-Gauge-Nadel zwischen dem distalen und dem proximalen Ligierung Nichtokklusives Draht. </li><li> Führen Sie den Drucksensor in die Arterie. Stellen Sie sicher, dass es keinen Blutverlust. Schieben Sie die 1,0 Französisch Millar Druckkatheter nach vorne und stellen Sie den proximalen nichtokklusiven Draht in einer Weise, dass der Katheter vorsichtig durch den Draht unter dem Schlüsselbein weiterzugeben. <ol><li> Minimierung der Blutverlust während der Einstellung des proximalen Nichtokklusives Draht. Den Drucksensor zu viel beim Vorrücken da es sehr instabil nicht komprimieren. Da der proximale Draht muss die Arterie nicht verschließen, sollte das Gefäß mit Blut gefüllt bleiben. </li></ol></li><li> Starten Sie die Aufnahme des Drucksignals. Eine arterielle Drucksignal fluctuates in einer gesunden Maus zwischen einem diastolischen Druck von 60 bis 70 mm Hg und einem systolischen Blutdruck von 100 bis 120 mm Hg. </li><li> Lenken des Katheters über den Truncus und über die Aorta in den linken Ventrikel. Der Kammerdruck schwankt zwischen 0 mm Hg und 100 bis 120 mm Hg. Zulassen, dass der Katheter in der linken Herzkammer zu stabilisieren. Nehmen das Signal für 30 min bis 60 min in Abhängigkeit von den experimentellen Anforderungen. </li><li> Nach Beendigung des Versuchs, genießen Sie den Katheter in Alconox 1% für 30 min. Den Katheter mit Milli-Q-Wasser waschen. Lagern Sie den Katheter in einer Schaumstoffblock. </li><li> Abrufen von Daten von der Software zur weiteren Analyse. <ol><li> Für die Datenanalyse, halten eine Zeitspanne, wo das Drucksignal stabil ist. Wählen mindestens 10 aufeinanderfolgenden Herzzyklen der aufgezeichneten Daten von Interesse. </li><li> Verwenden LabChart Software Version 8.0 oder ähnlich wie die Herzfrequenz, die maximale systolische linksventrikuläre Druck, den minimalen diastolischen linken ventr analysierenicular Druck, die Spitzenrate der isovolumetrischen linken ventrikulären Kontraktion (dP / dt max), der Spitzenrate der isovolumetrischen linksventrikulären Relaxation (dP / dt min), enddiastolischen linksventrikulären Drucks und die Zeitkonstante der linksventrikulären isovolumetrischen Druckabfall (tau) 7. HINWEIS: Der enddiastolische Druck entspricht dem Druck, bei dem Zeitpunkt, unmittelbar bevor die Druckwelle durch die isovolumetrischen Kontraktion induziert. Die Berechnung von Tau auf der Montage der linksventrikuläre Druck in einen monoexponentiellen Verlauf basieren, ausgedrückt als P (t) = P 0 e-t / &amp; tau + b, In dieser Formel ist P (t) ist die linke Herzkammerdruck zum Zeitpunkt t nach dem maximalen negativen Wert von dP / dt erreicht wurde. Der Parameter b entspricht der theoretischen Asymptote, die in einem vereinfachten Ansatz kann als Null angenommen werden. Verbesserte isovolumetrischen Entspannung führt zu einem kleineren Wert von tau. </li></ol></li></ol&gt;

<ol>
	<li>He, 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=Risk+factors+for+congestive+heart+failure+in+US+men+and+women:+NHANES+I+epidemiologic+follow-up+study.">Risk factors for congestive heart failure in US men and women: NHANES I epidemiologic follow-up study.</a> Arch Intern Med. 161, 996-1002 (2001).</li><li>Anversa, P., Sonnenblick, E. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ischemic+cardiomyopathy:+pathophysiologic+mechanisms.">Ischemic cardiomyopathy: pathophysiologic mechanisms.</a> Prog Cardiovasc Dis. 33, 49-70 (1990).</li><li>Erlebacher, J. A., Weiss, J. L., Weisfeldt, M. L., Bulkley, B. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+dilation+of+the+infarcted+segment+in+acute+transmural+myocardial+infarction:+role+of+infarct+expansion+in+acute+left+ventricular+enlargement.">Early dilation of the infarcted segment in acute transmural myocardial infarction: role of infarct expansion in acute left ventricular enlargement.</a> J Am Coll Cardiol. 4, 201-208 (1984).</li><li>Shimizu, I., 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=Excessive+cardiac+insulin+signaling+exacerbates+systolic+dysfunction+induced+by+pressure+overload+in+rodents.">Excessive cardiac insulin signaling exacerbates systolic dysfunction induced by pressure overload in rodents.</a> J Clin Invest. 120, 1506-1514 (2010).</li><li>Tirziu, 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=Myocardial+hypertrophy+in+the+absence+of+external+stimuli+is+induced+by+angiogenesis+in+mice.">Myocardial hypertrophy in the absence of external stimuli is induced by angiogenesis in mice.</a> J Clin Invest. 117, 3188-3197 (2007).</li><li>Theilmeier, 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=High-density+lipoproteins+and+their+constituent,+sphingosine-1-phosphate,+directly+protect+the+heart+against+ischemia/reperfusion+injury+in+vivo+via+the+S1P3+lysophospholipid+receptor.">High-density lipoproteins and their constituent, sphingosine-1-phosphate, directly protect the heart against ischemia/reperfusion injury in vivo via the S1P3 lysophospholipid receptor.</a> Circulation. 114, 1403-1409 (2006).</li><li>Weiss, J. L., Frederiksen, J. W., Weisfeldt, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemodynamic+determinants+of+the+time-course+of+fall+in+canine+left+ventricular+pressure.">Hemodynamic determinants of the time-course of fall in canine left ventricular pressure.</a> J Clin Invest. 58, 751-760 (1976).</li><li>Bohl, 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=Refined+approach+for+quantification+of+in+vivo+ischemia-reperfusion+injury+in+the+mouse+heart.">Refined approach for quantification of in vivo ischemia-reperfusion injury in the mouse heart.</a> Am J Physiol Heart Circ Physiol. 297, 2054-2058 (2009).</li><li>Van Craeyveld, E., Jacobs, F., Gordts, S. C., De Geest, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-density+lipoprotein+receptor+gene+transfer+in+hypercholesterolemic+mice+improves+cardiac+function+after+myocardial+infarction.">Low-density lipoprotein receptor gene transfer in hypercholesterolemic mice improves cardiac function after myocardial infarction.</a> Gene Ther. 19, 860-871 (2012).</li><li>Gordts, S. C., 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=Beneficial+effects+of+selective+HDL-raising+gene+transfer+on+survival,+cardiac+remodelling+and+cardiac+function+after+myocardial+infarction+in+mice.">Beneficial effects of selective HDL-raising gene transfer on survival, cardiac remodelling and cardiac function after myocardial infarction in mice.</a> Gene Ther. 20, 1053-1061 (2013).</li><li>Junqueira, L. C., Bignolas, G., Brentani, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Picrosirius+staining+plus+polarization+microscopy,+a+specific+method+for+collagen+detection+in+tissue+sections.">Picrosirius staining plus polarization microscopy, a specific method for collagen detection in tissue sections.</a> Histochem J. 11, 447-455 (1979).</li><li>Patten, R. D., Hall-Porter, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small+animal+models+of+heart+failure:+development+of+novel+therapies,+past+and+present.">Small animal models of heart failure: development of novel therapies, past and present.</a> Circ Heart Fail. 2, 138-144 (2009).</li><li>Zolotareva, A. G., Kogan, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+of+experimental+occlusive+myocardial+infarction+in+mice.">Production of experimental occlusive myocardial infarction in mice.</a> Cor Vasa. 20, 308-314 (1978).</li><li>Michael, L. H., 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=Myocardial+ischemia+and+reperfusion:+a+murine+model.">Myocardial ischemia and reperfusion: a murine model.</a> Am J Physiol. 269, 2147-2154 (1995).</li><li>Salto-Tellez, M., 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=Myocardial+infarction+in+the+C57BL/6J+mouse:+a+quantifiable+and+highly+reproducible+experimental+model.">Myocardial infarction in the C57BL/6J mouse: a quantifiable and highly reproducible experimental model.</a> Cardiovasc Pathol. 13, 91-97 (2004).</li><li>Fernandez, B., 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=The+coronary+arteries+of+the+C57BL/6+mouse+strains:+implications+for+comparison+with+mutant+models.">The coronary arteries of the C57BL/6 mouse strains: implications for comparison with mutant models.</a> J Anat. 212, 12-18 (2008).</li><li>Kumar, 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=Distinct+mouse+coronary+anatomy+and+myocardial+infarction+consequent+to+ligation.">Distinct mouse coronary anatomy and myocardial infarction consequent to ligation.</a> Coron Artery Dis. 16, 41-44 (2005).</li><li>Clauss, S. B., Walker, D. L., Kirby, M. L., Schimel, D., Lo, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patterning+of+coronary+arteries+in+wildtype+and+connexin43+knockout+mice.">Patterning of coronary arteries in wildtype and connexin43 knockout mice.</a> Dev Dyn. 235, 2786-2794 (2006).</li><li>Icardo, J. M., Colvee, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Origin+and+course+of+the+coronary+arteries+in+normal+mice+and+in+iv/iv+mice.">Origin and course of the coronary arteries in normal mice and in iv/iv mice.</a> J Anat. 199, 473-482 (2001).</li><li>Yoldas, A., Ozmen, E., Ozdemir, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macroscopic+description+of+the+coronary+arteries+in+Swiss+albino+mice+(Mus+musculus).">Macroscopic description of the coronary arteries in Swiss albino mice (Mus musculus).</a> J S Afr Vet Assoc. 81, 247-252 (2010).</li><li>James, T. N., Burch, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood+supply+of+the+human+interventricular+septum.">Blood supply of the human interventricular septum.</a> Circulation. 17, 391-396 (1958).</li><li>Gao, X. M., Xu, Q., Kiriazis, H., Dart, A. M., Du, X. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+model+of+post-infarct+ventricular+rupture:+time+course,+strain-+and+gender-dependency,+tensile+strength,+and+histopathology.">Mouse model of post-infarct ventricular rupture: time course, strain- and gender-dependency, tensile strength, and histopathology.</a> Cardiovasc Res. 65, 469-477 (2005).</li><li>Muthuramu, I., Jacobs, F., Singh, N., Gordts, S. C., De Geest, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+homocysteine+lowering+gene+transfer+improves+infarct+healing,+attenuates+remodelling,+and+enhances+diastolic+function+after+myocardial+infarction+in+mice.">Selective homocysteine lowering gene transfer improves infarct healing, attenuates remodelling, and enhances diastolic function after myocardial infarction in mice.</a> PLoS One. 8, 63710 (2013).</li><li>Eaton, L. W., Weiss, J. L., Bulkley, B. H., Garrison, J. B., Weisfeldt, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regional+cardiac+dilatation+after+acute+myocardial+infarction:+recognition+by+two-dimensional+echocardiography.">Regional cardiac dilatation after acute myocardial infarction: recognition by two-dimensional echocardiography.</a> N Engl J Med. 300, 57-62 (1979).</li><li>Erlebacher, J. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Late+effects+of+acute+infarct+dilation+on+heart+size:+a+two+dimensional+echocardiographic+study.">Late effects of acute infarct dilation on heart size: a two dimensional echocardiographic study.</a> Am J Cardiol. 49, 1120-1126 (1982).</li><li>Schuster, E. H., Bulkley, B. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expansion+of+transmural+myocardial+infarction:+a+pathophysiologic+factor+in+cardiac+rupture.">Expansion of transmural myocardial infarction: a pathophysiologic factor in cardiac rupture.</a> Circulation. 60, 1532-1538 (1979).</li><li>Jugdutt, B. I., Michorowski, B. L. <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+infarct+expansion+in+rupture+of+the+ventricular+septum+after+acute+myocardial+infarction:+a+two-dimensional+echocardiographic+study.">Role of infarct expansion in rupture of the ventricular septum after acute myocardial infarction: a two-dimensional echocardiographic study.</a> Clin Cardiol. 10, 641-652 (1987).</li><li>Pacher, P., Nagayama, T., Mukhopadhyay, P., Batkai, S., Kass, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+cardiac+function+using+pressure-volume+conductance+catheter+technique+in+mice+and+rats.">Measurement of cardiac function using pressure-volume conductance catheter technique in mice and rats.</a> Nat Protoc. 3, 1422-1434 (2008).</li><li>Vanden Bergh, A., Flameng, W., Herijgers, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parameters+of+ventricular+contractility+in+mice:+influence+of+load+and+sensitivity+to+changes+in+inotropic+state.">Parameters of ventricular contractility in mice: influence of load and sensitivity to changes in inotropic state.</a> Pflugers Arch. 455, 987-994 (2008).</li></ol>

None of the authors reports competing financial interests.

Chronischer Veränderungen der myokardialen Struktur und Funktion, kann die Entwicklung von linksventrikulärer Dysfunktion und Progression von Herzinsuffizienz in verschiedenen Mausmodellen 12 untersucht werden. Kardialen Remodeling und Funktionsstörungen können durch myokardiale Verletzungen oder induziert werden durch Drucküberlastung Sekundär der Quer Aortenkonstriktion, oder in genetischer Modelle der dilatativen Kardiomyopathie 12 untersucht werden. Offensichtlich ist die am stärksten au...

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with the cellular oxygen requirements at rest or during stress. It is characterized by fluid retention, shortness of breath, and fatigue, in particular on exertion. Heart failure is a growing public health problem, the leading cause of hospitalization, and a major cause of mortality. Ischemic heart disease is the main cause of heart failure1.
Ventricular remodelling refers to changes in structure, size, and shape of the left ventricle. In other words, ventricular remodelling concerns an alteration of the left ventricular architecture. This architectural remodelling of the left ventricle is induced by injury (e.g., myocardial infarction), by pressure overload (e.g., systemic arterial hypertension or aortic stenosis), or by volume overload (e.g., mitral insufficiency). Since ventricular remodelling affects wall stress, it has a profound impact on cardiac function and on the development of heart failure.
Loss of myocardial tissue following acute myocardial infarction results in a decreased systolic ejection and an increased left ventricular end-diastolic volume and pressure. The Frank-Starling mechanism, implying that an increased end-diastolic volume results in an increased pressure developed during systole, may help to restore cardiac output. However, the concomitant increased wall stress may induce regional hypertrophy in the non-infarcted segment, whereas in the infarcted area expansion and thinning may occur. Experimental animal studies show that the infarcted ventricle hypertrophies and that the degree of hypertrophy is dependent on the infarct size2. 
The loss of myocardial tissue following acute myocardial infarction results in a sudden increase in loading conditions. Post-infarct remodelling occurs in the setting of volume overload, since the stretched and dilated infarcted tissue increases the left ventricular volume. An increased ventricular volume not only implies increased preload (passive ventricular wall stress at the end of diastole) but also increased afterload (total myocardial wall stress during systolic ejection). Afterload is increased since the systolic radius is increased. Therefore, ventricular remodelling post-myocardial infarction is characterized by mixed features of volume overload and pressure overload.
The myocardium consists of 3 integrated components: cardiomyocytes, extracellular matrix, and the capillary microcirculation. All 3&#160;components are involved in the remodelling process. Matrix metalloproteinases produced by inflammatory cells induce degradation of intermyocyte collagen struts and cardiomyocyte slippage. This leads to infarct expansion characterized by the disproportionate thinning and dilatation of the infarct segment3. In later stages of remodelling, interstitial fibrosis is induced, which negatively affects the diastolic properties of the heart. 
The vascular and cardiomyocyte compartment in the myocardium should remain balanced in the process of ventricular remodelling to avoid tissue hypoxia4,5. Whether hypertrophy progresses to heart failure or not may be critically dependent on this balance between the vascular and cardiomyocyte compartment in the myocardium. 
A model of permanent ligation of the left anterior descending coronary artery in mice is used to investigate ventricular remodelling and cardiac function post-myocardial infarction. This model is fundamentally different in terms of objectives and pathophysiological relevance compared to the model of transient ligation of the left anterior descending coronary artery. In this latter model of ischemia/reperfusion injury, the initial extent of the infarct may be modulated by factors that affect myocardial salvage following reperfusion6. In contrast, the infarct area at 24 hours after permanent ligation of the left anterior descending coronary artery is fixed. Cardiac function in this model will be affected by 1) the process of infarct expansion, infarct healing, and scar formation; and 2) the concomitant development of left ventricular dilatation, cardiac hypertrophy, and ventricular remodelling.

<table border="0" cellpadding="0" cellspacing="0" width="1061">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">Reagents</td>
			<td style="width:223px;"></td>
			<td style="width:123px;"></td>
			<td style="width:495px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">Buprenorphine (Buprenex&#174;)</td>
			<td style="width:223px;">Bedford Laboratories</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:221px;">Sodium Pentobarbital (Nembutal&#174;)</td>
			<td style="width:223px;">Ceva</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:221px;">Betadine&#174;</td>
			<td style="width:223px;">VWR internationals</td>
			<td>200065-400</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">5 - 0 silk suture</td>
			<td>Ethicon, Johnson &#38; Johnson Medical</td>
			<td>K890H</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">6 - 0 prolene suture&#160;</td>
			<td>Ethicon, Johnson &#38; Johnson Medical</td>
			<td>F1832</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">6 - 0 Ti- Cron suture</td>
			<td>Ethicon, Johnson &#38; Johnson Medical</td>
			<td>F1823</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">Urethane&#160;</td>
			<td style="width:223px;">Sigma</td>
			<td>94300</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alconox</td>
			<td>Alconox Inc.</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;"></td>
			<td style="width:223px;"></td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">Equipment</td>
			<td style="width:223px;"></td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:221px;">Ventilator, MiniVent Model 845</td>
			<td style="width:223px;">Hugo Sachs</td>
			<td style="width:123px;">73-0043</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:221px;">Chest retractor or Thorax retractor</td>
			<td style="width:223px;">Kent Scientific corporation</td>
			<td style="width:123px;">INS600240</td>
			<td>ALM Self-retaining, serrated, 7cm long, 4 x 4 &#34;L&#34; shaped prongs, 3mm x 3mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1.0 French Millar pressure catheter&#160;</td>
			<td style="width:223px;">Millar Instruments&#160;</td>
			<td style="width:123px;">SPR - 1000/NR</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">Powerlab</td>
			<td style="width:223px;">ADInstruments Pty Ltd.</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">LabChart&#174; software</td>
			<td style="width:223px;">ADInstruments Pty Ltd.</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:221px;">Rectal probe</td>
			<td style="width:223px;">ADInstruments Pty Ltd.</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

permanent ligation of the left anterior descending coronary artery in mice: a model of post-myocardial infarction remodelling and heart failure

Herzinsuffizienz ist ein Syndrom, bei dem das Herz nicht Blut bei einer Rate mit zellulären Sauerstoffbedarf in Ruhe oder unter Belastung zu pumpen. Es wird von Flüssigkeitsretention, Kurzatmigkeit und Müdigkeit, insbesondere bei Belastung gekennzeichnet. Herzinsuffizienz ist ein wachsendes Problem der öffentlichen Gesundheit, die häufigste Ursache für Krankenhausaufenthalt und eine der Hauptursachen der Sterblichkeit. Ischämische Herzerkrankung ist die Hauptursache der Herzinsuffizienz. Remodeling bezeichnet Änderungen der Struktur, Größe und Form des linken Ventrikels. Diese architektonischen Remodellierung des linken Ventrikels durch Verletzung (zB Myokardinfarkt) induziert, die durch Drucküberlastung (zB arterielle Hypertonie oder Aortenstenose) oder durch Volumenüberlastung. Seit Remodeling wirkt Wandspannung, es hat eine tiefgreifende Wirkung auf die Herzfunktion und auf die Entwicklung einer Herzinsuffizienz. Ein Modell der permanenten Ligatur der linken vorderen descending Koronararterie bei Mäusen wird verwendet, um ventrikuläre Remodeling und die Herzfunktion nach einem Myokardinfarkt zu untersuchen. Dieses Modell ist in Bezug auf die Ziele und die pathophysiologische Relevanz im Vergleich zum Modell der vorübergehenden Unterbindung der linken vorderen absteigenden Koronararterie grundlegend anders. In diesem letzteren Modell der Ischämie / Reperfusionsverletzung, kann das anfängliche Ausmaß des Infarkts durch Faktoren, Myocardial Salvage nach Reperfusion beeinträchtigt moduliert werden. Im Gegensatz dazu ist der Infarktbereich bei 24 Stunden nach der Dauerunterbindung der linken vorderen absteigenden Koronararterie befestigt. Die Herzfunktion in diesem Modell wird durch 1) den Prozess der Infarktausdehnung, Infarkt Heilung und Narbenbildung beeinträchtigt werden; und 2) die gleichzeitige Entwicklung der Dilatation des linken Ventrikels, Herzhypertrophie und Remodeling. Neben dem Modell der permanenten Ligatur der linken vorderen absteigenden Koronararterie, die Technik der invasive hämodynamische measungen bei Mäusen wird im Detail vorgestellt.

Das Ausmaß der Myokardinfarkt kann durch Evans blue / 2,3,5-Triphenyltetrazoliumchlorid (TTC) Doppelfärbung beurteilt werden. TTC ist ein Redox-Indikator, der tiefroten 1,3,5-triphenylformazan in lebenden Geweben aufgrund der Aktivität verschiedener Dehydrogenasen in Gegenwart von NADH 8 umgewandelt wird. 1 zeigt einen repräsentativen Abschnitt des Herzens bei 24 h nach der Ligation des linken vorderen absteigenden Koronararterie. Blau gefärbte Bereiche zeigen nicht-ischämischen / norma...

Watch this Scientific Journal Video about Permanent Ligation of the Left Anterior Descending Coronary Artery in Mice: A Model of Post-myocardial Infarction Remodelling and Heart Failure at JoVE.com

Permanent Ligation of the Left Anterior Descending Coronary Artery in Mice: A Model of Post-myocardial Infarction Remodelling and Heart Failure

Heart failure is the leading cause of hospitalization and a major cause of mortality. A model of permanent ligation of the left anterior descending coronary artery in mice is applied to investigate ventricular remodelling and cardiac dysfunction post-myocardial infarction. The technique of invasive hemodynamic measurements in mice is presented.

Permanent Ligation des linken vorderen absteigenden Koronararterie bei Mäusen: Ein Modell der Post-Myokardinfarkt Umbau und Herzinsuffizienz

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It ...

permanent-ligation-left-anterior-descending-coronary-artery-mice

Research

JoVE Journal

Medicine

27.5K Aufrufe.  Catholic University of Leuven. Heart failure is the leading cause of hospitalization and a major cause of mortality. A model of permanent ligation of the left anterior descending coronary artery in mice is applied to investigate ventricular remodelling and cardiac dysfunction post-myocardial infarction. The technique of invasive hemodynamic measurements in mice is presented.

Serie: Permanent Ligation of the Left Anterior Descending Coronary Artery in Mice: A Model of Post-myocardial Infarction Remodelling and Heart Failure

Coronary Artery Ligation and Intramyocardial Injection in a Murine Model of Infarction

Mouse models are a valuable tool for studying acute injury and chronic remodeling of the myocardium in vivo. With the advent of genetic modifications to the whole organism or the myocardium and an array of biological and/or synthetic materials, there is great potential for any combination of these to assuage the extent of acute ischemic injury and impede the onset of heart failure pursuant to myocardial remodeling. 
Here we present the methods and materials used to reliably perform this microsurgery and the modifications involved for temporary (with reperfusion) or permanent coronary artery occlusion studies as well as intramyocardial injections. The effects on the heart that can be seen during the procedure and at the termination of the experiment in addition to histological evaluation will verify efficacy. 
Briefly, surgical preparation involves anesthetizing the mice, removing the fur on the chest, and then disinfecting the surgical area. Intratracheal intubation is achieved by transesophageal illumination using a fiber optic light. The tubing is then connected to a ventilator. An incision made on the chest exposes the pectoral muscles which will be cut to view the ribs. For ischemia/reperfusion studies, a 1 cm piece of PE tubing placed over the heart is used to tie the ligature to so that occlusion/reperfusion can be customized. For intramyocardial injections, a Hamilton syringe with sterile 30gauge beveled needle is used. When the myocardial manipulations are complete, the rib cage, the pectoral muscles, and the skin are closed sequentially. Line block analgesia is effected by 0.25% marcaine in sterile saline which is applied to muscle layer prior to closure of the skin. The mice are given a subcutaneous injection of saline and placed in a warming chamber until they are sternally recumbent. They are then returned to the vivarium and housed under standard conditions until the time of tissue collection. At the time of sacrifice, the mice are anesthetized, the heart is arrested in diastole with KCl or BDM, rinsed with saline, and immersed in fixative. Subsequently, routine procedures for processing, embedding, sectioning, and histological staining are performed. 
Nonsurgical intubation of a mouse and the microsurgical manipulations described make this a technically challenging model to learn and achieve reproducibility. These procedures, combined with the difficulty in performing consistent manipulations of the ligature for timed occlusion(s) and reperfusion or intramyocardial injections, can also affect the survival rate so optimization and consistency are critical.

Numerous genetic manipulations and/or intramyocardial injections of genes, proteins, cells, and/or biomaterials are superimposed upon the dimension of time in studies of acute ischemia/ reperfusion injury and chronic remodeling in mice. This video illustrates the microsurgical procedures for ischemia/reperfusion, permanent coronary artery ligation, and intramyocardial injection studies.

Koronare Ligation und intramyokardialen Injection in einem Mausmodell der Infarkt

Mouse models are a valuable tool for studying acute injury and chronic remodeling of the myocardium in vivo.  With the advent of genetic modifications to ...

Forschung

Medizin

The Application Of Permanent Middle Cerebral Artery Ligation in the Mouse

Focal cerebral ischemia is among the most common type of stroke seen in patients. Due to the clinical significance there has been a prolonged effort to develop suitable animal models to study the events that unfold during ischemic insult. These techniques include transient or permanent, focal or global ischemia models using many different animal models, with the most common being rodents.
The permanent MCA ligation method which is also referred as pMCAo in the literature is used extensively as a focal ischemia model in rodents 1-6. This method was originally described for rats by Tamura et al. in 1981 7. In this protocol a craniotomy was used to access the MCA and the proximal regions were occluded by electrocoagulation. The infarcts involve mostly cortical and sometimes striatal regions depending on the location of the occlusion. This technique is now well established and used in many laboratories 8-13. Early use of this technique led to the definition and description of &#x201C;infarct core&#x201D; and &#x201C;penumbra&#x201D; 14-16, and it is often used to evaluate potential neuroprotective compounds 10, 12, 13, 17. Although the initial studies were performed in rats, permanent MCA ligation has been used successfully in mice with slight modifications 18-20 .
This model yields reproducible infarcts and increased post-survival rates. Approximately 80% of the ischemic strokes in humans happen in the MCA area 21 and thus this is a very relevant model for stroke studies. Currently, there is a paucity of effective treatments available to stroke patients, and thus there is a need for good models to test potential pharmacological compounds and evaluate physiological outcomes. This method can also be used for studying intracellular hypoxia response mechanisms in vivo. 
Here, we present the MCA ligation surgery in a C57/BL6 mouse. We describe the pre-surgical preparation, MCA ligation surgery and 2,3,5 Triphenyltetrazolium chloride (TTC) staining for quantification of infarct volumes.

Middle cerebral artery (MCA) ligation is a technique to study focal cerebral ischemia in animal models. In this method, the middle cerebral artery is exposed by craniotomy and ligated by cauterization. This method gives highly reproducible infarct volumes and increased post-operative survival rates compared to other methods available.

Die Anwendung des dauerhaften mittleren Hirnarterie Ligation in der Maus

Focal cerebral ischemia is among the most common type of stroke seen in patients. Due to the clinical significance there has been a prolonged effort to ...

Modified Technique for Coronary Artery Ligation in Mice

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI we need better knowledge about pathophysiology of myocardial ischemia. This knowledge may be valuable to define new therapeutic targets for innovative cardiovascular therapies4. Experimental MI model in mice is an increasingly popular small-animal model in preclinical research in which MI is induced by means of permanent or temporary ligation of left coronary artery (LCA)5. In this video, we describe the step-by-step method of how to induce experimental MI in mice.
The animal is first anesthetized with 2% isoflurane. The unconscious mouse is then intubated and connected to a ventilator for artificial ventilation. The left chest is shaved and 1.5 cm incision along mid-axillary line is made in the skin. The left pectoralis major muscle is bluntly dissociated until the ribs are exposed. The muscle layers are pulled aside and fixed with an eyelid-retractor. After these preparations, left thoracotomy is performed between the third and fourth ribs in order to visualize the anterior surface of the heart and left lung. The proximal segment of LCA artery is then ligated with a 7-0 ethilon suture which typically induces an infarct size ~40% of left ventricle. At the end, the chest is closed and the animals receive postoperative analgesia (Temgesic, 0.3 mg/50 ml, ip). The animals are kept in a warm cage until spontaneous recovery.

The surgical procedure used to induce experimental myocardial infarction in mice begins with left thoracotomy between the third and the fourth ribs in order to visualize the anterior surface of the heart and left lung. The left coronary artery is ligated, the chest is closed and the mouse is allowed to recover spontaneously.

Geändert Technik für Coronary Artery Ligation in Mäuse

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI ...

A Murine Model of Myocardial Ischemia-reperfusion Injury through Ligation of the Left Anterior Descending Artery

Acute or chronic myocardial infarction (MI) are cardiovascular events resulting in high morbidity and mortality. Establishing the pathological mechanisms at work during MI and developing effective therapeutic approaches requires methodology to reproducibly simulate the clinical incidence and reflect the pathophysiological changes associated with MI. Here, we describe a surgical method to induce MI in mouse models that can be used for short-term ischemia-reperfusion (I/R) injury as well as permanent ligation. The major advantage of this method is to facilitate location of the left anterior descending artery (LAD) to allow for accurate ligation of this artery to induce ischemia in the left ventricle of the mouse heart. Accurate positioning of the ligature on the LAD increases reproducibility of infarct size and thus produces more reliable results. Greater precision in placement of the ligature will improve the standard surgical approaches to simulate MI in mice, thus reducing the number of experimental animals necessary for statistically relevant studies and improving our understanding of the mechanisms producing cardiac dysfunction following MI. This mouse model of MI is also useful for the preclinical testing of treatments targeting myocardial damage following MI.

We introduce a surgical method to induce experimental ischemia/reperfusion (I/R) injury to simulate myocardial infarction (MI) in mouse models that allows for more clarity in positioning of the ligation on the left anterior descending artery (LAD) to increase the reproducibility of MI experiments in mice.

Einem Mausmodell der myokardialen Ischämie-Reperfusion Injury durch Ligation des linken vorderen absteigenden Arterie

Acute or chronic myocardial infarction (MI) are cardiovascular events resulting in high morbidity and mortality. Establishing the pathological mechanisms ...

Murine Left Anterior Descending (LAD) Coronary Artery Ligation: An Improved and Simplified Model for Myocardial Infarction

Ischemic heart disease (IHD), or acute coronary syndrome (ACS), is one of the leading causes of death in the United States. IHD is characterized by reduced blood supply to the heart, resulting in the loss of oxygen to and the ensuing necrosis of the heart muscle. The MI model has gained popularity for its use as a short-term ischemia-reperfusion model and a long-term permanent ligation model. Below, we describe a reliable method for the permanent ligation of the LAD. With mouse genetic engineering technology becoming more advanced, and with an increasing availability of quality murine surgical instruments, the mouse has become a popular model for MI surgeries. Our surgical model incorporates the use of an easily reversible anesthetic for the rapid recovery of the mouse; a minimally invasive endotracheal intubation without involving a tracheotomy; and a thoracentesis through the original thoracotomy site without creating an additional incision in the chest, as is done in some other methods, to effectively remove excess blood and air from the chest cavity. This method is comparatively less invasive than other methods, which dramatically reduces surgical and post-surgical complications and mortality and improves reproducibility.

Murine Left Anterior Descending LAD Coronary Artery Ligation: An Improved and Simplified Model for Myocardial Infarction

We provide a reliable method for left anterior descending artery (LAD) ligation in a mouse model. This method is comparatively less invasive than other methods, involving endotracheal intubation, a left-sided thoracotomy approach, and thoracentesis. This method can be used as a model for both acute and chronic myocardial infarction (MI).

Murine linken vorderen absteigenden (LAD) Koronararterienligatur: ein verbessertes und vereinfachtes Modell für Myokardinfarkts

Ischemic heart disease (IHD), or acute coronary syndrome (ACS), is one of the leading causes of death in the United States. IHD is characterized by ...

Direct Re-implantation of Left Coronary Artery into the Aorta in Adults with Anomalous Origin of Left Coronary Artery from the Pulmonary Artery (ALCAPA)

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly which is one of leading causes of myocardial ischemia and infarction in children. If left untreated, it results in a 90% mortality rate in the first year of life. In patients who survive to the adulthood, the coronary steal phenomenon and retrograde left-sided coronary flow provide a substrate for chronic subendocardial ischemia, which may lead to left ventricular dysfunction, ischemic mitral regurgitation, malignant ventricular arrhythmias, and sudden cardiac death. The average age of life-threatening presentation is 33 years and of sudden cardiac death 31 years. Therefore, surgical correction is highly recommended as soon as the diagnosis is made, regardless of age. In adult-type ALCAPA originating from the right-facing sinus of the pulmonary artery, direct re-implantation of the ALCAPA into the aorta is the more physiologically sound repair technique to re-establish the dual-coronary perfusion system and is recommended. This protocol describes the technique of direct re-implantation of adult-type ALCAPA into the aorta.

Direct Re-implantation of Left Coronary Artery into the Aorta in Adults with Anomalous Origin of Left Coronary Artery from the Pulmonary Artery ALCAPA

Surgical correction of ALCAPA is highly recommended, regardless of age or the degree of intercoronary collateralization. This protocol presents a technique for the direct re-implantation of adult-type ALCAPA into the aorta to re-establish the dual-coronary perfusion. Whenever feasible, direct re-implantation is preferred to other surgical correction techniques.

Direkter Wieder Implantation von linken Koronararterie in die Aorta bei Erwachsenen mit Anomale Ursprung der linken Koronararterie aus der Lungenarterie (ALCAPA)

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly which is one of leading causes of myocardial ...

Murine Myocardial Infarction Model using Permanent Ligation of Left Anterior Descending Coronary Artery

Myocardial infarction (MI) and acute coronary diseases are among the most prominent causes of death in population with western lifestyle. The murine models of MI with permanent ligation of left-anterior descending (LAD) coronary artery closely mimics MI in humans. Murine models benefit from the extensive genetic engineering available nowadays. Here we propose a reproducible murine surgical model of myocardial infarction by permanent LAD coronary ligation. Our technique comprises anesthesia with ketamine/xylazine that can be rapidly reversed by administration of an antagonist, intubation without tracheotomy for mechanical-assisted ventilation, ventilation with application of extrinsic positive end-expiratory pressure (PEEP) to avoid alveolar collapse, a thoracotomy method limiting to the minimum surgical lesions made to skeletal muscles, and lung inflation without thoracentesis. This method is sparsely invasive, reproducible and reduces post-surgery mortality and complications.

Herein we describe a surgical procedure showing how to achieve permanent ligation of the left-anterior descending coronary artery in mice. This model is of high relevance to investigate the pathophysiology of myocardial infarction and the concomitant biological processes.

Murine Myokardinfarkt Modell mit permanenten Ligation der linken Anterior absteigende Koronararterie

Myocardial infarction (MI) and acute coronary diseases are among the most prominent causes of death in population with western lifestyle. The murine ...

Establishing a Swine Model of Post-myocardial Infarction Heart Failure for Stem Cell Treatment

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major causes of mortality and morbidity around the world. Cell-based therapies for cardiac repair and improvement of left ventricular function after MI have attracted considerable attention. Accordingly, the safety and efficacy of these cell transplantations should be tested in a preclinical large animal model of HF prior to clinical use. Pigs are widely used for cardiovascular disease research due to their similarity to humans in terms of heart size and coronary anatomy. Therefore, we sought to present an effective protocol for the establishment of a porcine chronic HF model using closed-chest coronary balloon occlusion of the left circumflex artery (LCX), followed by rapid ventricular pacing induced with pacemaker implantation. Eight weeks later, the stem cells were administered by intramyocardial injection in the peri-infarct area. Then the infarct size, cell survival, and left ventricular function (including echocardiography, hemodynamic parameters, and electrophysiology) were evaluated. This study helps establish a stable preclinical large animal HF model for stem cell treatment.

We sought to establish a swine model of heart failure induced by left circumflex artery blockage and rapid pacing to test the effect and safety of intramyocardial administration of stem cells for cell-based therapies.

Erstellung eines Schweinemodells für postmyokarde Infarkt-Herzinsuffizienz für die Stammzellbehandlung

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major ...

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

The development of heart failure is the most powerful predictor of long-term mortality in patients surviving acute myocardial infarction (MI). There is an unmet clinical need for prevention and therapy of post-myocardial infarction heart failure (post-MI HF). Clinically relevant pig models of post-MI HF are prerequisites for final proof-of-concept studies before entering into clinical trials in drug and medical device development.
Here we aimed to characterize a closed-chest porcine model of post-MI HF in adult G&#246;ttingen minipigs with long-term follow-up including serial cardiac magnetic resonance imaging (CMRI) and to compare it with the commonly used Landrace pig model.
MI was induced by intraluminal balloon occlusion of the left anterior descending coronary artery for 120 min in G&#246;ttingen minipigs and for 90 min in Landrace pigs, followed by reperfusion. CMRI was performed to assess cardiac morphology and function at baseline in both breeds and at 3 and 6 months in G&#246;ttingen minipigs and at 2 months in Landrace pigs, respectively.
Scar sizes were comparable in the two breeds, but MI resulted in a significant decrease of left ventricular ejection fraction (LVEF) only in G&#246;ttingen minipigs, while Landrace pigs did not show a reduction of LVEF. Right ventricular (RV) ejection fraction increased in both breeds despite the negligible RV scar sizes. In contrast to the significant increase of left ventricular end-diastolic (LVED) mass in Landrace pigs at 2 months, G&#246;ttingen minipigs showed a slight increase in LVED mass only at 6 months.
In summary, this is the first characterization of post-MI HF in G&#246;ttingen minipigs in comparison to Landrace pigs, showing that the G&#246;ttingen minipig model reflects post-MI HF parameters comparable to the human pathology. We conclude that the G&#246;ttingen minipig model is superior to the Landrace pig model to study the development of post-MI HF.

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

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 G&#246;ttingen minipigs and the characterization of post-MI HF model in G&#246;ttingen minipigs as compared to Landrace pigs.

Postmyokardinfarkt Herzinsuffizienz in geschlossener Koronierung/Reperfusion Modell in Göttingen Minischweine und Landrasse Schweine

The development of heart failure is the most powerful predictor of long-term mortality in patients surviving acute myocardial infarction (MI). There is an ...

Generation and Characterization of Right Ventricular Myocardial Infarction Induced by Permanent Ligation of the Right Coronary Artery in Mice

Right ventricular infarction (RVI) is a common presentation in clinical practice. Severe RVI can lead to fatal hemodynamic dysfunction and arrhythmia. In contrast to the extensively used mouse myocardial infarction (MI) model generated by left coronary artery ligation, the RVI mouse model is rarely employed due to the difficulty associated with model generation. Research on the mechanisms and treatment of RVI-induced RV remodeling and dysfunction requires animal models to mimic the pathophysiology of RVI in patients. This study introduces a feasible procedure for RVI model generation in C57BL/6J mice. Further, this model was characterized based on the following: infarct size evaluation at 24 h after MI, assessment of cardiac remodeling and function with echocardiography, RV hemodynamics assessment, and histology of the infarct zone at 4 weeks after RVI. In addition, a coronary vasculature cast was performed to observe the coronary arterial arrangement in RV. This mouse model of RVI would facilitate the research on mechanisms of right heart failure and seek new therapeutic targets of RV remodeling.

There are several differences between the right and left ventricles. However, the pathophysiology of right ventricular infarction (RVI) has not been clarified. In the present protocol, a reproducible method for RVI mouse model generation is introduced, which may provide a means to explain the mechanism of RVI.

Erzeugung und Charakterisierung eines rechtsventrikulären Myokardinfarkts induziert durch permanente Ligation der rechten Koronararterie bei Mäusen

Right ventricular infarction (RVI) is a common presentation in clinical practice. Severe RVI can lead to fatal hemodynamic dysfunction and arrhythmia. In ...