M Wiberg1, J E Niskanen2, M Hytönen2, K Dillard3, K Hagner4, M Anttila5, H Lohi2. 1. Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, P.O BOX 57, 00014, Helsinki, Finland. Electronic address: maria.wiberg@helsinki.fi. 2. Department of Veterinary Biosciences, Department of Medical Genetics, Medicum, University of Helsinki, Folkhälsan Research Center, Helsinki, Haartmaninkatu 8, 00290, Helsinki, Finland. 3. Department of Veterinary Biosciences, Department of Medical Genetics, Medicum, University of Helsinki, Folkhälsan Research Center, Helsinki, Haartmaninkatu 8, 00290, Helsinki, Finland; Veterinary Bacteriology and Pathology Research Unit, Finnish Food Authority, P.O. BOX 200, 00027, Helsinki, Finland. 4. Veterinary Pathology and Parasitology, Department of Veterinary Biosciences, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, 00014, Helsinki, Finland. 5. Veterinary Bacteriology and Pathology Research Unit, Finnish Food Authority, P.O. BOX 200, 00027, Helsinki, Finland.
Abstract
INTRODUCTION: To describe unexpected sudden cardiac death (SCD) in young Leonbergers (<3 years) and to review the circumstances before death and necropsy findings; to prospectively evaluate the presence of possible arrhythmias in young Leonbergers; and to examine pedigrees for determining potential modes of inheritance. ANIMALS: Postmortem evaluations included 21 Leonbergers. Clinical evaluation consisted of 46 apparently healthy Leonbergers with and without a close family history of SCD. MATERIALS AND METHODS: Necropsy reports were reviewed retrospectively. Prospective clinical evaluation included physical examination, 5-min electrocardiogram, 24-h Holter, echocardiography, and laboratory tests. Pedigree data were examined for mode of inheritance. RESULTS: Based on necropsy reports, SCD occurred at a median age of 12 months (range, 2.0-32.0 months) without any previous clinical signs and usually in rest. No evidence of structural cardiac disease was found; arrhythmia-related death was suspected. Clinical evaluation and 24-h Holter showed ventricular arrhythmia (VA) in 14 apparently healthy Leonbergers (median age, 18 months; range, 12-42 months). Severity of VA varied from infrequent couplets/triplets to frequent complexity (couplets, triplets, nonsustained ventricular tachycardias,VTs) characterized by polymorphology. During follow-up, two dogs with polymorphic VT died. Although breed specificity and high prevalence indicate a heritable disease, based on available pedigree data, the mode of inheritance could not be determined. CONCLUSIONS: Sudden cardiac death in young Leonbergers is associated with malignant VA characterized by complexity and polymorphic nature. Diagnosis is based on 24-h Holter monitoring. Pedigree analysis suggests that the arrhythmia is familial.
INTRODUCTION: To describe unexpected sudden cardiac death (SCD) in young Leonbergers (<3 years) and to review the circumstances before death and necropsy findings; to prospectively evaluate the presence of possible arrhythmias in young Leonbergers; and to examine pedigrees for determining potential modes of inheritance. ANIMALS: Postmortem evaluations included 21 Leonbergers. Clinical evaluation consisted of 46 apparently healthy Leonbergers with and without a close family history of SCD. MATERIALS AND METHODS: Necropsy reports were reviewed retrospectively. Prospective clinical evaluation included physical examination, 5-min electrocardiogram, 24-h Holter, echocardiography, and laboratory tests. Pedigree data were examined for mode of inheritance. RESULTS: Based on necropsy reports, SCD occurred at a median age of 12 months (range, 2.0-32.0 months) without any previous clinical signs and usually in rest. No evidence of structural cardiac disease was found; arrhythmia-related death was suspected. Clinical evaluation and 24-h Holter showed ventricular arrhythmia (VA) in 14 apparently healthy Leonbergers (median age, 18 months; range, 12-42 months). Severity of VA varied from infrequent couplets/triplets to frequent complexity (couplets, triplets, nonsustained ventricular tachycardias,VTs) characterized by polymorphology. During follow-up, two dogs with polymorphic VT died. Although breed specificity and high prevalence indicate a heritable disease, based on available pedigree data, the mode of inheritance could not be determined. CONCLUSIONS:Sudden cardiac death in young Leonbergers is associated with malignant VA characterized by complexity and polymorphic nature. Diagnosis is based on 24-h Holter monitoring. Pedigree analysis suggests that the arrhythmia is familial.
Authors: Hannah J Harjen; Annelin A Bjelland; Joanne Harris; Tone K Grøn; Kristin P Anfinsen; Elena R Moldal; Runa Rørtveit Journal: J Vet Intern Med Date: 2020-06-18 Impact factor: 3.333
Authors: Anna Letko; Katie M Minor; Vidhya Jagannathan; Franz R Seefried; James R Mickelson; Pieter Oliehoek; Cord Drögemüller Journal: Genet Sel Evol Date: 2020-10-14 Impact factor: 4.297