24-Hour Holter Monitor
A portable ECG device worn for 24 hours that records every heartbeat. Essential for detecting arrhythmias that may not appear during a brief vet visit.
What it measures
Total heart beats over 24 hours, number and types of arrhythmias (VPCs, ventricular tachycardia, atrial fibrillation), heart rate variability, and whether arrhythmias occur during rest, activity, or sleep. A normal dog has fewer than 50 VPCs in 24 hours.
What to expect
Small adhesive electrodes are placed on your dog's chest (a patch of fur is shaved). A small recording device is attached to a vest or wrap your dog wears. Your dog goes home and lives normally for 24 hours while it records. You'll keep a diary of your dog's activities (eating, walking, sleeping) to correlate with the recording. You return the monitor the next day.
Typical cost
$200-400 for the rental and interpretation. Some clinics charge separately for the interpretation by the cardiologist.
How often
Screening: annually for Dobermans and Boxers starting at age 2-4. Monitoring: every 6-12 months for dogs on antiarrhythmic medications (sotalol, mexiletine). After dose changes: 7-14 days to assess effectiveness.
Conditions detected
Breeds that need this test
In-depth guide
Read our complete guide to 24-hour holter monitorfor dogs →
Need to schedule a holter?
Find a board-certified veterinary cardiologist near you who can perform this test and interpret the results.
Find a cardiologist →Medical disclaimer: Heart Dog Club provides educational information only and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian or board-certified veterinary cardiologist (DACVIM-Cardiology) regarding your dog's health.