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Cardiology

Complex ventricular arrhythmias in a 3-month-old Dachshund

02 July 2024
Case Report
15 mins read
02 July 2024
Volume 29 · Issue 9

Abstract

Complex ventricular arrhythmias were diagnosed in an asymptomatic 3-month-old female Dachshund. Based on the patient's signalment, electrocardiographic findings and exclusion of other differentials, a channelopathy was suspected. The dog was treated with oral sotalol, mexiletine and magnesium supplementation. This case report demonstrates the use of ambulatory electrocardiogram analysis and the complexity of assessing arrhythmia mechanisms, and discusses the approach to, and treatment of, ventricular arrhythmias in this case.

Ventricular arrhythmias are abnormal heart rhythms that originate in the ventricles. They can range from isolated and relatively benign to complex and life threatening. The mechanisms of these are complex and can be difficult to determine based on a surface electrocar-diogram, but analysis can guide differential diagnoses and anti-ar-rhythmic drug selection. Juvenile inherited arrhythmias are documented in the literature and particularly investigated in German Shepherd dogs, with sporadic reports of inherited arrhythmias in other breeds (Moïse et al, 1994; Reuter et al, 2024). This case report describes the approach to diagnosis and treatment of a complex ventricular arrhythmia initially documented in a 3-month-old asymptomatic Dachshund.

A 3-month-old female Dachshund was referred following detection of an arrhythmia by the attending veterinarian at a routine vaccination appointment. There were no reported clinical signs. Physical examination revealed an alert and ambulatory patient, weighing 4.1 kg with reduced body (World Small Animal Veterinary Association score – 3/9; World Small Animal Veterinary Association, 2013a) and muscle condition (World Small Animal Veterinary Association score – B; World Small Animal Veterinary Association, 2013b). The patient's heart rate was 148 bpm with an irregularly irregular rhythm and pulse deficits. There was no audible heart murmur. Systolic blood pressure (Doppler method) was 130 mmHg.

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anti-arrhythmic treatment
arrhythmia mechanisms
electrocardiography
juvenile arrhythmias
ventricular arrhythmias