Introduction
- Cause : slowed conduction through the atrioventricular node:
- Can be due to excessive vagal tone, metabolic disorders, cardiomyopathies or idiopathic.
- Can be found in clinically normal dogs - may be benign in many cases.
- Signs : usually an incidental finding; if advanced, there can be weakness or syncope.
- Diagnosis : clinically, usually no abnormality on auscultation; electrocardiography.
- Treatment : usually none, but may respond temporarily to atropine
. - Prognosis : usually very good.
Diagnosis
Clinical signs
- Usually no abnormal findings on clinical examination.
- May be pronounced sinus arrhythmia (regular irregularity).
Sequelae
Prognosis
- Good, if not a complication of another disease.
Expected response to treatment
- Lack of development of clinical signs.
- No progression of ECG findings.
Reasons for treatment failure
- Progression of any underlying extraneous disease, eg CNS, respiratory.
Sources
Publications
Other sources of information
- Lunney J & Ettinger S J (1995) Cardiac arrhythmias. In: Textbook of Veterinary Internal Medicine.4th edn. Eds S J Ettinger & E C Feldman. Philadelphia: W B Saunders.
- Smith F W K, Tilley L P & Miller M S (1994) Electrocardiography. In: Saunders Manual of Small Animal Practice.Eds S J Birchard & R G Scherding. Philadelphia: W B Saunders.
- Tilley L P (1992) Essentials of Canine and Feline Electrocardiography. 3rd edn. Philadelphia: Lea & Febiger.
- Sisson D D (1989) Bradyarrhythmias and cardiac pacing. In: Current Veterinary Therapy X.Ed R W Kirk. Philadelphia: W B Saunders.
