• SYSTEM(S) EFFECTED:
    		•  Heart and Respiratory system
  • CAUSE(S):
    		• Build-up of fluid due to malfunction of heart mechanism
  • DIAGNOSTICS:
    		• Minimal to Extensive
  • TREATMENT:
    		• Drug therapy
  • PREVENTION:
    		• No

GENERAL DESCRIPTION

 Congestive heart failure is a weakness in some part of the heart pumping mechanism, or inadequate strength of your pet’s heart to meet it’s body’s need for oxygen. The heart consists of four chambers; the two upper atria and two lower ventricles. There are blood vessels in between the chambers that open to allow one-way flow to the ventricles and close to prevent backflow into the atria. The left side of the heart pumps blood out to the body, while the right side pumps blood to the lungs.
 
Congestive heart failure tends to be more prevalent in older and obese animals. Very large dog breeds, as well as toy and teacup sized breeds seem to be more prone to this condition. 

SOURCE & CAUSE(S)

 Heart problems and failure can be caused by old age, a number of diseases, heartworm disease, birth defects, or, most commonly, a build-up of fluid in or around the heart (congestive heart failure). Congestive heart failure is caused by an abnormality in the heart, resulting in a back up of fluid in the heart, lungs, or chest cavity. This could be caused from too much fluid or pressure in the heart, the heart’s contractions not being strong enough to empty the chambers, or the chambers not being able to hold an adequate amount of blood.  

SIGNS & SYMPTOMS

Depending on which side of the heart is weakened or disabled, your pet may exhibit different signs early on:
  • Shortness of breath
  • Unproductive coughing due to build-up of fluid in the lungs - mostly found in left-sided heart failure
  • Fainting or collapsing
  • Loss of appetite
  • Lethargy
  • Bloated belly due to build-up of fluid in the chest cavity - mostly found in right-sided heart failure (less common than left-sided failure)  
As the problem progresses, distress, labored breathing, gray/blue gums, dilated pupils, and seizures may occur. This could be an emergency situation and you should contact your vet ASAP.  

 


DIAGNOSIS & TESTS 

Diagnosis begins with a complete history and a physical exam.  Your veterinarian will most likely do the following:
  • History and Physical Exam - Your veterinarian will likely listen to your pet’s heart with a stethoscope to observe any murmurs or gurgling sounds indicating a build-up of fluid. They may also take a blood pressure reading which is typically a non-invasive process requiring no sedation. Your pet’s symptoms and breed history will be taken into account in their diagnosis.
  • Radiographs (X-rays)- This may show clouded lungs or abdomen, indicating fluid accumulation. X-rays may also show an enlarged heart. 
  • Ultrasound- This can be used in many diagnostic processes to determine abnormalities in your pet’s body. Ultrasounds use sound waves that bounce back producing an echo that measures the opacity of objects and produces a picture on the ultrasound machine. When an ultrasound is performed to observe the structure of the heart, it is called an echocardiogram.
  • Electrocardiogram- This test measures and records the electric impulses of your pet’s heart. This is usually done by clipping small contact electrodes to your pet’s limbs. It is a harmless process, but usually requires sedation to get an accurate reading.
  • ELISA testing - Your veterinarian may wish to test your pet for heartworm disease if your pet is not on a heartworm preventative. This will help them rule heartworm disease out as the cause of heart problems and coughing. ELISA stands for "enzyme-linked immunosorbent assay" is a test used to determine if a pet has been exposed to a certain pathogen by seeing if it’s body has produced antibodies against the pathogen. It can be used to test for viruses, bacteria, microbes, or other material.  This SNAP ELISA test requires just a few drops of whole blood from your dog and can be run in about 10 minutes. This test will show a positive if there is enough of the heartworm antigen in the bloodstream. Once it is positive, an additional blood test known as a direct test, a sample again of whole blood is examined under the microscope and the young heartworms can be seen.

 


 TREATMENT & MANAGEMENT 

There is no cure for congestive heart failure, but measures can be taken to extend and increase the quality of your pet’s life.
  • Your veterinarian will likely prescribe drugs that will alleviate the fluid pressure in the heart and lungs, as well as regulate the heart beat.
  • A drug called Vetmedin is often prescribed to open up your pet’s blood vessels and reduce the amount of work their heart has to do to pump blood.
  • A diuretic drug such as Furosemide may be prescribed to flush the fluid out of your pet’s cavities
  • A thoracocentesis may be performed to manually drain the fluid from your pet’s lungs with a needle. This may require sedation and/or an ultrasound to help your guide the needle.
  • There are multiple natural supplement options for dogs with congestive heart failure; those that include potassium, taurine, selenium, chromium, L-carnitine, among others.

 


 PREVENTION & HELPFUL TIPS 

Keeping your pet at a healthy weight for their size can greatly assist the heart in pumping blood. The more overweight your pet, the harder the heart has to work and the more severe the heart issues. Talk to your vet about ways you can help your pet lose weight through exercise (consult your veterinarian first before engaging your heart-diseased pet in any strenuous exercise) and a reduced-calorie and low salt/high protein diet. An adjustment in your pet’s lifestyle may be the answer.
 
Early diagnosis of congestive heart failure can prevent further fluid acculmulation and heart deterioration and may elongate your pet’s life.

Written by: PetsMD Veterinary Editorial Staff