[en] OBJECTIVE: To assess morphologic and metabolic abnormalities in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP). ANIMALS: 7 Beagles. PROCEDURE: Plasma carnitine concentrations were measured before and after development of ELVD induced by RRVP. At the same times, transvenous endomyocardial biopsy was performed, and specimens were submitted for determination of myocardial carnitine concentrations and histologic, morphometric, and ultrastructural examination. RESULTS: In 4 dogs in which baseline plasma total carnitine concentration was normal, RRVP induced a decrease in myocardial total and free carnitine concentrations and an increase in myocardial esterified carnitine concentration. In 3 dogs in which baseline plasma total carnitine concentration was low, plasma and myocardial carnitine concentrations were unchanged after pacing. Structural changes associated with pacing included perinuclear vacuolization in 3 dogs. Morphometric analyses indicated there was a decrease in myofiber cross-sectional diameter and area following pacing. Electron microscopy revealed changes in myofibrils and mitochondria following pacing. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that moderate to severe alterations in myocyte cytoarchitecture are present in dogs with ELVD induced by RRVP and that in dogs with normal plasma carnitine concentrations, myocardial carnitine deficiency may be a biochemical marker of ELVD. Results also indicated that transvenous endomyocardial biopsy can be used to evaluate biochemical and structural myocardial changes in dogs with cardiac disease.
Disciplines :
Veterinary medicine & animal health
Author, co-author :
Mc Entee, Kathleen ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Sémiologie et clinique médicale des petits animaux
Flandre, Thierry
Dessy, Cécile ; Université de Liège - ULiège > Services généraux (Faculté de médecine vétérinaire) > Relations académiques et scientifiques (Méd. vétérinaire)
Desmecht, Daniel ; Université de Liège - ULiège > Département de Morphologie et Pathologie > Pathologie spéciale et autopsies
Clercx, Cécile ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Pathologie médicale des petits animaux
Grauwels, Magda ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Département clinique des animaux de compagnie et des équidés
Geudvert, Claudine ; Centre Hospitalier Universitaire de Liège - CHU > Médecine de l'appareil locomoteur
Jonville, Eva
Miserque, N.
Henroteaux, Marc ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Département clinique des animaux de compagnie et des équidés
Keene, B.
Language :
English
Title :
Metabolic and Structural Abnormalities in Dogs with Early Left Ventricular Dysfunction Induced by Incessant Tachycardia
Kittleson MD. Primary myocardial disease leading to chronic myocardial failure (dilated cardiomyopathy and related diseases). In: Kittleson MD, Kienle RD, ed. Small animal cardiovascular medicine. St Louis: Mosby Inc, 1998:319-346.
Calvert CA. Update. Canine dilated cardiomyopathy. In: Kirk RW, Bonagura JD, eds. Current veterinary therapy XI. Philadelphia: WB Saunders Co, 1992;773-779.
Wilson JR, Douglas P, Mickey WF, et al. Experimental congestive heart failure produced by rapid ventricular pacing in the dog: cardiac effects. Circulation 1987;75:857-867.
Spinale FG, Fulbright BM, Mukherjee R, et al. Relation between ventricular and myocyte function with tachycardia-induced cardiomyopathy. Circ Res 1992;71:174-187.
Travill CM, Williams TDM, Pate P, et al. Haemodynamic and neurohumoral response in heart failure produced by rapid ventricular pacing. Cardiovasc Res 1992;26:783-790.
Komamura K, Shannon P, Ihara T, et al. Exhaustion of Franck-Starling mechanism in conscious dogs with heart failure. Am J Physiol 1993;265:H1119-H1131.
Pierpont MEM, Foker JE, Pierpont GL. Myocardial carniline metabolism in congestive heart failure induced by incessant tachycardia. Basic Res Cardiol 1993;88:362-370.
Redfield MM, Aarhus LL, Wright RS, et al. Cardiorenal and neurohumoral function in a canine model of early left ventricular dysfunction. Circulation 1993;87:2016-2022.
Stevens TL, Burnett JC, Kinoshita M, et al. A functional role for endogenous atrial natriuretic peptide in a canine model of early left ventricular dysfunction. J Clin Invest 1995;95:1101-1108.
Mc Entee K, Clercx C, Soyeur D, et al. Usefulness of tests for detection of cardiac abnormalities in dogs with experimentally induced early left ventricular dysfunction. Am J Vet Res 2001;62: 448-455.
Parvin R, Pande SV. Microdetermination of carnitine and carnitine acyltransferase activity. Anal Biochem 1977;79:190-201.
Keene BW. L-Carnitine deficiency in canine dilated cardiomyopathy. In: Kirk RW, ed. Current veterinary therapy XI. Philadelphia: WB Saunders Co, 1992;780-783.
Keene BW, Kittleson ME, Atkins CE, et al. Modified transvenous endomyocardial biopsy technique in dogs. Am J Vet Res 1990; 51:1769-1772.
SAS user's guide: version 6 edition. 4th ed. Vol 2. Cary, NC: SAS Institute Inc, 1989.
Masumura Y, Kobayashi A, Yamazakin. Myocardial free carnitine and fatty acylcarnitine levels in patients with chronic heart failure. Jpn Circ J 1990;54:1471-1476.
Pepine CJ. The therapeutic potential of carnitine in cardiovascular disorders. Clin Ther 1991;13:2-21.
Shug AL, Thomsen JH, Folts JD, et al Changes in tissue levels of carnitine and other metabolites during myocardial ischemia and anoxia. Arch Biochem Biophys 1978;187:25-33.
Regitz V, Bossaller C, Strasser R, et al. Metabolic alterations in end-stage and less severe heart failure: myocardial carnitine decrease. J Clin Chem Clin Biochem 1990;28:611-617.
Regitz V, Shug AL, Fleck E. Defective myocardial carnitine metabolism in congestive heart failure secondary to dilated cardiomyopathy and to coronary, hypertensive and valvular heart disease. Am J Cardiol 1990;65:755-760.
Pierpont MEM, Judd D, Goldenberg IF, et al. Myocardial carnitine in end stage heart failure. Am J Cardiol 1989;64:56-60.
Nakamura T, Sugihara H, Kinoshita N, et al. Serum carnitine concentrations in patients with idiopathic hypertrophic cardiomyopathy: relationship with impaired myocardial fatty acid metabolism. Clin Sci 1999;97:493-501.
Miyagawa J, Kuwajima M, Hanafusa T, et al. Mitochondrial abnormalities of muscle tissue in mice with juvenile visceral steatosis associated with systemic carnitine deficiency. Virchows Arch 1995;426:271-279.
Van Vleet JF, Ferrans VJ. Myocardial diseases of animals. Am J Pathol 1986;124:99-178.