sinus bradycardia in dogs
sb is fairly common in dogs, especially cocker spaniels, dachshunds, pugs, west highland white terriers, and female miniature schnauzers. furthermore, this condition is more common in young than old dogs, and the incidence decreases with age, unless caused by an underlying disease.
Reading: Low heart rate in dogs
symptoms and types
Your dog may not show symptoms if he is very active or participating in sports training. Sinus bradycardia (heartbeats less than 60 beats per minute, although it depends on the environment and size of the animal) is usually more noticeable when your dog is at rest. Some other common symptoms associated with sinus bradycardia include:
- exercise intolerance
- episodic muscle incoordination (ataxia)
- excessively slow breathing (hypoventilation), especially under anesthesia
- athletic conditioning (this is not uncommon in athletic dogs)
- underlying disease(s); for example, respiratory, neurological and gastrointestinal diseases
Your veterinarian will perform a complete physical exam on your dog, taking into account history of symptoms, your dog’s general condition, and possible incidents that could have caused it.
A complete blood profile will be performed, including a chemical blood profile, a complete blood count, and a urinalysis, the results of which may indicate the presence of substances that could be causing a slower heart rate. these tests will also reveal deficiencies in the blood if that is the underlying cause. they may also offer clues to possible kidney failure. Your doctor may also use x-rays and ultrasound to visually examine your dog’s internal organs for abnormalities in the heart, kidneys, and other organs. An electrocardiogram (EKG) recording can be used to examine the electrical currents in the heart muscles and can reveal any abnormalities in cardiac electrical conduction, which underlies the heart’s ability to contract and beat. an initial 24-hour cardiac monitoring may be indicated to conclude a diagnosis.
treatment will be determined by any underlying disease found. many dogs do not show clinical signs and do not require treatment. in dogs without structural heart disease, heart rates as low as 40 to 50 bpm (beats per minute) can usually still provide normal cardiac output at rest. therapeutic approaches vary markedly; they depend on the cause of the sb, the ventricular rate, and the severity of clinical signs.
If your dog is in critical condition, he may be treated as an inpatient, where intravenous fluid therapy can be administered and the dog’s health stabilized. Activity restrictions will not be recommended unless your dog has a symptomatic syndrome related to structural heart disease; then exercise restriction will be recommended until medical and/or surgical intervention can stabilize the problem.
housing and administration
Your doctor will order additional monitoring based on the final diagnosis. signs, if present, should resolve with correction of underlying underlying condition. however, the overall long-term prognosis varies depending on the nature of the structural heart disease, if any. for example, treatment of symptomatic bs with a permanent pacemaker generally offers a good prognosis for rhythm control.