Heart disease is the No. 4 cause of death in dogs,
according to Dr. Ryan Fries, a veterinary cardiologist at the University of Illinois Veterinary Teaching Hospital in Urbana. The causes, symptoms, diagnosis, and treatment of heart problems in pets can vary widely.
“Congenital heart disease—ones the animal is born with—can sometimes lead to heart failure. The good news is that if we detect and can surgically correct the problem, these animals can live relatively normal lives,” says Dr. Fries.
For heart problems associated with aging and degenerative disease, if the condition worsens to heart failure, there is no cure, although medical management may improve quality of life and extend the animal’s life for a time.Heart disease may arise when any part of the heart, such as the muscles or valves, is working inadequately. When the heart is not able to keep up with the demands of the body due to the disease, it becomes heart failure. The left or right side of the heart can fail, causing a backup of blood and fluid accumulation in the heart, lungs, stomach, or elsewhere in the body.
“Certain breeds or species are genetically predisposed to a particular form of heart disease,” explains Dr. Fries.
“Degenerative valve disease, a condition in which the heart valves do not seal properly, is estimated to affect greater than 30 percent of all canine patients and is the most common cause of heart failure in dogs,” says Dr. Fries. “Some small breeds are especially susceptible. Cavalier King Charles spaniels, miniature poodles, and Yorkshire terriers often develop degenerative valve disease when they are middle-aged to older.”
Giant breeds, such as Dobermans, are prone to an issue called dilated cardiomyopathy, where the heart becomes weak and enlarged. Cats often get hypertrophic cardiomyopathy, where the heart becomes thickened and ineffective.
How would an owner know if their pet has heart disease? Coughing, difficulty breathing, fainting, or other respiratory problems could be indications of heart failure.
“Sometime an animal just isn’t acting normally,” says Dr. Fries. “The change could be as small as not wanting to go for car rides or being a little less active than normal.”
Luckily, pets are screened for heart disease at every visit to the veterinarian. Fluid in the belly, distension, or abnormal pulses are possible indications of heart problems that could be discovered during a routine exam.
“Listening with a stethoscope is the best screening tool we have. If a murmur or arrhythmia is heard, the veterinarian will pursue other diagnostics, such as chest X-rays to see the size of the heart and whether there is fluid in the lungs, and an EKG to check heart rhythm,” says Dr. Fries.
Blood pressure is checked in pets with heart disease because elevated blood pressure can make the heart condition worse.
An echocardiogram—an ultrasound of the heart—allows the veterinary cardiologist to watch the heart pumping in order to locate the problem and diagnose the specific disease.
Management of heart disease depends on the severity. If an animal is asymptomatic, they may not need treatment, and the animal can be monitored.
“Unfortunately, we don’t know enough about heart disease in pets to understand what causes the transition from an asymptomatic disease to heart failure,” says Dr. Fries.
For animals that develop symptomatic heart failure, a combination of three drugs has proven effective in increasing life expectancy from a few months to a year or more.
Furosemide diuretics are prescribed to eliminate water from the body, which reduces the effort the heart must expend to circulate the blood. Ace inhibitors also lessen the work load on the heart by modifying hormones and biomarkers that are activated by heart failure.
“Pimobendan is relatively new drug in veterinary cardiology that helps the heart to pump stronger and allows the body to move blood more efficiently. It is a huge step forward in management of heart failure,” says Dr. Fries.
The most important thing pet owners can do to protect their animals from heart failure is to diagnose the disease early.
“Bring your pets to the veterinarian annually or more frequently when they get older to monitor for heart issues” says Dr. Fries. “The sooner we can intervene, the better chance we have of giving your pet a longer, healthier life.”
If you have any questions about heart disease, please ask your local veterinarian.
By Melissa Giese