Red September is the month dedicated to raising awareness about cardiovascular diseases, not only in humans but also in pets.
Among dogs, heart diseases are more common than people imagine, and early identification is essential to ensure quality of life and longevity. In this context, the Holter exam – widely used in human medicine – has gained prominence in Veterinary Medicine as an important diagnostic tool for identifying silent cardiac arrhythmias.
Through continuous monitoring of the heart's electrical activity for 24 hours or more, the Holter allows Veterinarians to assess the animal's cardiac behavior through a dynamic approach together with the use of the Cardio Pet Vest developed by Pet Med, offering more accurate data at different times of the day, including during sleep, feeding, and light exercise.
To talk to us about the importance of the Holter and how its use can help prevent arrhythmias in dogs, we spoke with Veterinarian Patrícia Pereira Costa Chamas, Professor and Doctor at Paulista University (UNIP) and Metropolitan University of Santos (UNIMES). She holds a Master's and Doctorate from the Faculty of Veterinary Medicine of the University of São Paulo (USP).
Follow the interview and, at the end of the reading, share it with your friends and family.
Pet Med – What is Red September and what is the importance of this campaign for pet cardiac health?
Patrícia Chamas - Red September is a campaign organized to raise awareness among owners about heart diseases that can affect their pets and the importance of performing routine cardiological exams for early identification, monitoring, and/or treatment of these diseases.
Pet Med – What are the most common arrhythmias in dogs and what signs can owners notice at home?
Patrícia Chamas - There are benign and sometimes even physiological arrhythmias, such as sinus arrhythmia. However, there are other more concerning ones that can even cause sudden death in dogs and cats, such as ventricular tachycardia. Often, these are asymptomatic, but some pets affected by more severe arrhythmias may exhibit syncope (fainting), easy fatigue, and panting.
Pet Med – What is Holter monitoring and how does it work in veterinary practice?
Patrícia Chamas - Holter monitoring is, literally, a 24-hour electrocardiogram. During this 24-hour period, the heart rhythm is recorded with every heartbeat on a flashcard-type memory card that stays inside the Holter recorder. When the exam is finished, this card is removed from the device and connected to a computer where software performs computerized analysis of the exam. After this analysis, a professional in the field performs a more detailed analysis of these 24 hours of recording. During the 24 hours of the exam, the owner keeps a diary, recording the main activities performed by the animal during the exam, so that the signs they exhibit can or cannot be associated with the presence of cardiac rhythm disturbances.
Pet Med – Is Holter only for diagnosis or does it also help prevent cardiac problems?
Patrícia Chamas - The Holter does not help prevent cardiac disorders, but it can diagnose cardiac diseases related to rhythm changes in their earliest stage.
Pet Med – In which cases do you recommend the Holter?
Patrícia Chamas - The Holter is recommended for all patients who experience syncope (fainting), as some cardiac arrhythmias are strongly correlated with this clinical manifestation. Fainting is very common in patients with ventricular tachycardia secondary to certain diseases, such as in Doberman dogs with dilated cardiomyopathy, Boxer or Bulldog dogs with arrhythmogenic cardiomyopathy, or in patients with arrhythmias associated with low heart rate (bradyarrhythmias, such as atrioventricular blocks). Therefore, dogs with syncope or breeds predisposed to these aforementioned diseases should be routinely evaluated with 24-hour electrocardiographic monitoring.
Pet Med – What is the difference between the Holter and the traditional electrocardiogram performed at the clinic?
Patrícia Chamas - The main difference is the duration of the exam. While a conventional electrocardiogram records about 3 to 5 minutes of heart rhythm, the Holter records 24 hours, greatly increasing the chance of recording intermittent arrhythmias and allowing not only the recording of the arrhythmia but also its quantity and complexity over 24 hours of recording.
Pet Med – How does 24-hour recording increase the chance of detecting intermittent arrhythmias?
Patrícia Chamas - The 24-hour heart rhythm recording is much longer than a conventional electrocardiogram, which allows for the detection of intermittent arrhythmias, which only occur during certain periods of the day.
Pet Med – How does the veterinarian use the Holter data to guide treatment or lifestyle changes for the dog?
Patrícia Chamas - The Holter provides the veterinarian not only with the record of the type of arrhythmia present in a patient, but also its quantity and complexity, and all this data will be used by the Veterinary Cardiologist to assess the need for treatment and the best drugs to be used for each patient, in an individualized way.
Pet Med – How does the Cardio Pet vest from Pet Med contribute to electrode fixation and improve the accuracy of Holter results?
Patrícia Chamas - The vest keeps the electrodes stable and well-adhered to the patient's body, resulting in a high-quality electrocardiographic tracing. If the electrodes are a little loose, the lack of full contact with the patient's skin can generate a lot of interference in the tracing, leading to difficulty in interpreting the exam or the lack of recording of important arrhythmias that may have occurred during periods of interference.
Pet Med – What should pet owners know before, during, and after the exam for effective monitoring?
Patrícia Chamas - To obtain a good electrocardiographic tracing with the Holter and more reliable results, the owner must stay with their animal during the 24 hours of the exam, monitoring them and writing a diary with the main activities carried out during the period, and should not let the patient rub the device against the wall or floor, so as not to generate periods of interference in the tracing. Additionally, the device cannot get wet, and the owner must prevent their pet from biting the device or trying to remove it with their teeth.
Pet Med – Finally, what message do you have for pet owners during "Red September" regarding the importance of preventive exams, especially the Holter?
Patrícia Chamas - Although it is a laborious exam that requires a certain financial and time investment from families, the Holter is an extremely important cardiological exam because it can provide valuable information for the diagnosis of cardiac arrhythmias or for monitoring the therapy of some arrhythmias, sometimes preventing fatal outcomes that some arrhythmias can cause.
It is worth noting that the interpretation of a Holter exam in Veterinary Medicine is more difficult than in Human Medicine, since the software used is human, not adapted to pets. For this reason, the exam result may take 7 to 15 days to be released. However, in emergency cases, the professional who reads the exam can give a preliminary result to the colleague who requested the exam.
