4 Dangers of an Enlarged Heart in Dogs Having a Large Heart Isn't Always a Good Thing

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An englarged heart in dogs can be potentially fatal if not diagnosed and treated promptly. So it's important to know the causes, symptoms, and possible dangers of an enlarged heart.

Heart health can be a big concern for dog owners, especially those who are raising certain breeds. For instance, the Doberman PinscherBoxer, Scottish Deerhound, Irish WolfhoundGreat DaneSaint Bernard, Afghan Hound, and Cocker Spaniel all have a greater risk of developing an enlarged heart, also known as dilated cardiomyopathy (DCM), as compared to other breeds.

An enlarged heart in dogs develops when the heart’s muscles weaken, causing pressure in the heart’s blood vessels to increase and, in turn, stretching the muscles. Valvular defects, heartbeat abnormalities, tumors, and heartworms can all be behind the initial weakening of the muscles. Heartworm prevention is easy with the help of an appropriate heartworm medicine like Interceptor.

When these muscles enlarge, several dangers can follow, such as:

1. Heart Murmur / Arrhythmias

Due to the enlarged muscles, the heart’s valves cannot close completely, causing blood to flow backward, thus creating a murmur. Arrhythmias occur when the electrical impulses of the heart don't work properly, causing an irregular heartbeat. These impulses can be thrown off as the muscles enlarge.

2. Distended Abdomen

A distended abdomen will typically occur when the muscles on the right side of the heart enlarge so much that they fail and fluid begins to build up in the abdomen. This buildup then puts pressure on the diaphragm, causing trouble breathing. You might also notice your dog eating less or occasionally vomiting, both of which can lead to weight loss and malnutrition. Ask your vet about Cerenia for dogs in case of excessive vomiting. 

3. Fluid in the Lungs

Fluid in the lungs will typically occur when the muscles in the left side of the heart enlarge so much that they fail, causing fluid to pool in the lungs. This buildup then fills space in the lungs needed to bring oxygen into the bloodstream. In addition to causing a lingering cough, heavy breathing, fatigue, fainting, and even a bluing of the lips or tongue, fluid buildup in the lungs can also result in death. Medicines like Theophylline for dogs, Cefpodoxime Proxetil, and Cephalexin for dogs can help with lung infections. 

4. Heart Failure

Congestive heart failure occurs when the heart’s muscles enlarge to a point at which they can no longer meet the circulatory demands of the body, often resulting in death.

Enlarged hearts, if they do develop, normally develop in dogs between 4 to 10 years of age and can be found via a radiograph of the chest. The severity of the condition is determined with an ultrasound, which will show how much muscle function is left. However, your vet may spot the condition during a thorough physical exam.

Depending on how severe the condition is, your vet can prescribe medication to help the heart contract more effectively. They will also schedule regular checkups to track any progress, which can be determined with radiographs, blood pressure measurements, EKGs, and biochemical tests. Enalapril for dogs and Pimobendan for dogs can be used in case your dog does experience heart failure. 

Unfortunately, in most cases, by the time the condition is spotted and diagnosed, it is too late -- life expectancy is usually determined to be under six months. But within those months, your vet can best advise you on how to make your dog's life as comfortable as possible.

How Do You Determine if There Is a Problem?

The best way to determine whether or not your dog has an enlarged heart is by taking a complete history of their health and reviewing current blood work. Things to keep in mind include:

Symptoms consistent with an enlarged heart can include difficulty breathing, coughing or wheezing, exercise intolerance, fainting spells, weakness, lethargy (tiredness), and collapse after exercise. Changes in the size of the chest and abdomen may also be present if there is fluid buildup around the heart or lungs.

Auscultation (listening) of the chest with a stethoscope can help reveal abnormal sounds that may indicate murmurs associated with valvular disease or congestive heart failure. An echocardiogram will provide more information about what structures are affected within the heart itself. 

Echocardiograms can also help detect any valve leakage problems as well as any enlargement present in either chamber of your pet's heart. On occasion, other tests such as x-rays may be necessary depending on findings from echocardiogram results. However, these tests do not necessarily need both results before making decisions about treatment options for dogs suffering from CHF because, many times, one test alone will answer questions regarding diagnosis and severity.

How Do You Treat Your Dog’s Enlarged Heart?

If your dog is diagnosed with an enlarged heart, there are several treatment options to consider. Medication can be used to help control the symptoms of cardiomyopathy and reduce stress on the heart. Surgery is another option that can be considered in some cases. If your dog's condition is severe enough, surgery may be required to repair any damage done by his enlarged heart. This procedure may be successful in relieving symptoms and improving your dog's quality of life for a time, but it does not cure cardiomyopathy or prevent further complications from developing later on down the road (which will require additional surgeries). 

Surgery also carries its risks: anesthesia-related complications such as infections or difficulty breathing; blood loss during surgery; postoperative pain; difficulty recovering from anesthesia; possible death due to existing medical problems exacerbated by surgery (such as kidney failure). Vetmedin for dogs is the main treatment for heart disease, along with supplements like Nordic Naturals Omega 3 and Salmon Oil for dogs. For the kidney, Furosemide for dogs is a tried and tested medicine. 

So, what are the four dangers of an enlarged heart in dogs? Well, they're all pretty scary. In the end, though, if you can get your dog diagnosed early and start treatment as soon as possible (ideally before any symptoms show up), then he or she should be able to live a long and happy life. You might even be able to avoid some of these dangers altogether!

More on Heart Health

7 Risk Factors for Congestive Heart Failure in Dogs
Nutrition for Cats and Dogs With Heart Disease
Heart Disease in Dogs and Cats

This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis or treatment by, your veterinarian with respect to your pet. It has, however, been verified by a licensed veterinarian for accuracy.

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