Heart Failure

Heart Failure
By Dr. Karen Burgess

What does heart failure mean?
The heart is a muscular organ that contains four separate blood holding chambers.  The heart muscle functions to push or pump blood held in these chambers through the body’s blood vessels.  When the heart is unable to push blood forward at a rate that keeps up with the body’s demand it is considered heart failure.  Heart failure typically leads to fluid backing up into the lungs.

What causes heart failure?
There are a variety of diseases that can lead to heart failure.  Pets with a heart murmur, or leaky heart valve account for 80% of heart failure cases in dogs.   In some cases the heart muscle is abnormal, either too thick or too thin.  Lung disease can also put added stress on heart muscle.

What is the significance of heart failure?
Heart failure can be chronic disease with symptoms waxing and waning or acute in nature leading to sudden death.  When blood flow to the body is affected energy level, organ function, and the ability to breathe can all be affected.  Owners may also notice an enlarged belly (from fluid buildup), gums that are blue or paler than usual, and weight loss.

What are symptoms of heart failure?
Pets experiencing heart failure are often first seen for coughing, in particular after exertion of first thing in the morning.  Other signs include exercise intolerance, reluctance to go for walks, and change in sleep pattern or position.

What tests are indicated if heart failure is suspected?
If a pet is experiencing collapse or severe breathing issue from heart failure it may be life-threatening within minutes to hours and immediate medical attention is necessary.   Hospitalization and oxygen support along with medications may be required in these situations.  Radiographs (x-rays) are often used to evaluate for heart failure which will often produce an enlarged heart shape of evidence of fluid buildup in the lungs.  Blood pressure, EKG evaluation, and blood tests are often recommended to further evaluate the impact of heart failure on the rest of the body.  Ultimately an echocardiogram (ultrasound of the heart) allows a veterinarian to understand the specific disease affecting the heart.

What is involved with treatment for heart failure?
Often pets with heart failure are able to be managed with oral medications for some time period after diagnosis allowing them to live a relatively normal quality of life.   It is helpful in managing heart failure patients to monitor their breathing rate while sleeping; changes in this number may indicate that a pet is having more troubles related to their heart function.

Is heart failure the same as a heart attack?
Heart attacks are common in humans and occur when blood flow to the heart muscle is interrupted thus leading to death of the heart muscle known as a myocardial infarct.  This is not a common cause of death or heart disease in cats and dogs.