Sinus and Atrial Dysrhythmias Flashcards
What happens to the P wave in an animal with a wandering pacemaker (sinus arrhythmia)?
When the HR increases, the P wave becomes larger; when the HR decreases, the P wave becomes smaller
What is a sinus arrhythmia?
Changes in vagal tone (inhalation and exhalation) lead to regularly irregular distances between R waves on ECG paper
T/F: Treatment is required for sinus arrhythmias
F
Define sinus braycardia
Slowing of the HR, usually due to physiologic predominance of the parasympathetic system
What are 7 causes of sinus bradycardia?
Opioids Gastrointestinal disease Respiratory disease Increased intracranial pressure Asphyxiation Alpha-2 agonists Ocular disease
T/F: Treatment is required for sinus bradycardia
T… IF pt is hemodynamically compromised
How is sinus bradycardia treated? (5)
Remove underlying imbalance
Anticholinergic drugs
Temporary cardiac pacing
Alpha-2 agonists (medetomidine, xylazine)
Define sinus arrest
No sinus activity for greater than 2 R-R intervals (escape beats pick up slack)
Define sinus tachycardia
Quickening of the HR, usually due to physiologic predominance of the sympathetic system
What are 6 causes of sinus tachycardia?
Pain Hypovolemia Anemia CHF Iatrogenic Pheochromocytoma
T/F: Treatment is required for sinus tachycardia
T IF pt is hemodynamically compromised
How is sinus tachycardia treated? (3)
Remove underlying imbalance
Beta-blockers (Esmolol)
Calcium channel blockers (diltiazem)
How do you know an ECG is showing a sinus rhythm?
Upright P wave
What is sick sinus syndrome?
Sinus dysfunction with or without AV involvement
What breeds are predisposed to sick sinus syndrome?
Miniature Schnauzer
Cocker Spaniel
West Highland White Terrier
Dachshund
