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Advanced Veterinary Specialists

Recognizing Signs of Heart Disease in Pets

Owner Sitting with Dog at the Dock by the Lake

Early detection of heart disease in pets can be pivotal in any pet’s long-term prognosis and the initial detection often occurs at home. The ability of family members to recognize the common clinical signs relating to heart disease is important to obtain a diagnosis and thereby initiate proper treatment for our animal companions.

The cardiovascular system is complex with many organs and biochemical processes that work together in a perfect balance in healthy animals. When this system is compromised, pets will begin to show gradual or obvious changes, which can be detected with informed observational skills.

We aim to review the many different signs that can suggest your pets are experiencing cardiovascular compromise that can be detected by family members in the home environment.

Respiratory Distress

One of the most sensitive signs of heart disease in pets is an increase in the respiration rate while sleeping. Normally the respiration rate should be less than 32 breaths per minute or approximately a breath every two seconds. This can be observed by counting how many gentle rises or falls of the chest occur over one minute. If this rate is increased or is also accompanied by an abdominal effort, cardiac compromise may be indicated. If this rate is consistently elevated, then your pet should have a cardiopulmonary evaluation by a Veterinarian as soon as possible.


A more obvious sign of heart disease is a recent and persistent cough, often most pronounced in the morning, evening, and when rising from a reclined position. Early detection of heart disease in cats can be even more difficult to detect for typically they do not cough with cardiac disease, but will display an increased breathing effort. Cats also exhibit an open-mouth breathing pattern, which is accompanied by an increase in respiratory rate and effort suggestive of cardiac disease.

Exercise Intolerance

Other detectable symptoms that can be appreciated is a decline in activity, reluctance to exercise, or general weakness, referred to as exercise intolerance. Dogs or cats may become tired after short bouts of exercise far sooner than what they could previously tolerate, breathing heavier for a longer period of time afterward. At times their gums may change color to a purplish or pale hue.


Your pet may experience collapsing or fainting episodes if severe cardiac disease is present. This may result either from irregularities with your pet’s heart electrical activity called arrhythmias or severe decline in heart function. This serious clinical sign should be promptly evaluated by a Veterinarian. Cats can experience collapsing episodes with paralysis of either front or hind limbs and vocalization. This is a severe medical emergency and veterinary care should be sought out immediately.

Changes in Behavior

A general restlessness may occur, especially at night, appearing as if they are having a difficult time finding a comfortable place to lay down. Withdrawn or hiding behavior is more often seen in cats with heart disease. The appearance of generalized depression has also been described.

Weight Fluctuations

Weight loss is strongly linked to long-standing heart disease in pets, but your pet may experience what appears to be weight gain as well. This would appear as a bloated or distended abdomen due to inappropriate fluid retention.

Being mindful of these signs can help your beloved companion receive the proper medical attention in a timely manner. If at any time you have any questions regarding the health of your pet, please contact your Veterinarian with your concerns. The well-being of your pet is our highest priority.