By: Dr. Barry Miller
"What a beautiful world it would be
if people had hearts like dogs"
Author Unknown
Although our pets do not suffer from heart attacks or clogged arteries like their human pet parents, they do have similar heart conditions.
How can a heart so big and full of love suffer from any heart condition?
Just like our hearts dog hearts age as they grow old too.
Some are born with a genetic disorder of the heart.
Pet's can live with heart disease long before they show any signs of it.
This can make early detection difficult but early detection can make all the difference in your pet's health. Please see the section called the Top 10 Signs of Heart Disease in your pet.
Getting to the know the heart:
Picture the heart as a pump that receives blood on one side and then forces the blood through the lungs to receive oxygen. On the other side the oxygenated blood is pumped to the rest of the body.
The heart has four chambers. The upper chambers are called atria (one chamber is called an atrium) and the lower chambers are called ventricles. The heart is also divided into right and left sides. Blood needs to flow in one direction through the heart, valves prevent the backward flow of blood or the flow of blood in the wrong direction.
What is Congestive Heart Failure?
Congestive heart failure begins when the heart is unable to provide the tissues with adequate oxygen and nutrients. Without adequate oxygen, the body's cells become distressed and trigger a series of responses. Congestive Heart Failure or CHF can occur due to several different types of diseases.
CHF is an inability of the heart to pump oxygenated blood to the rest of the body this causes congestion or blood backing up into the lungs or other areas of the body. This excess fluid most commonly collects in your pet's lungs, or the space around their lungs and in their abdomen. This causes one of the most common symptoms of CHF, coughing.
What is a Heart Murmur?
In my experience as a small animal practitioner, 90% of the heart disease cases that I diagnose have a Heart Murmur.
Murmurs are abnormal vibrations that your Veterinarian can hear when listening to your pet's heart. These vibrations or murmurs are produced due to a disturbance in the blood flow through your pet's heart, usually caused by damage to the heart valves or a change in the health of the heart valves. Murmurs are classified according to a variety of characteristics, including their timing.
* Systolic murmurs occur when the heart muscle contracts
* Diastolic murmurs occur when the heart muscle relaxes between beats
* Continuous and to-and-fro murmurs occur throughout all or most of the cardiac cycle.
Murmurs are also classified by the valve that it involves. For example a very common heart murmur is Mitral Valve Insufficiency.
What is Mitral Valve Insufficiency:
Mitral valve disorder occurs as the mitral valve ages, changes and thereby fails to completely close off the area on the left side of the heart between the two chambers. This means that it is no longer able to prevent the backward flow of blood inside the heart. The left lower ventricle or chamber is powerful and when the mitral valve fails at its job the left ventricles can easily force some of the blood backward back in the left upper atrium or chamber each time the heart beats. This increases the pressure within the heart and makes it more difficult for the heart to function properly and causes an increase of blood pressure back into the lungs.
This increased pressure within the lungs results in fluid buildup or fluid on the lungs when this occurs fluid actually leaves the blood vessels and leaks into the tissues. The medical term used to describe 'fluid in the lungs' is 'pulmonary edema.'
As the condition progresses, the right side of the heart starts to fail because of its increased work and elevated pressures. At first the muscles strengthen, thereby increasing the mass and thickness of its walls. Over time, however, even these 'athletic' muscles cannot keep up with the ever-increasing pressures and they start to fail. During this congestive heart failure, the animal will be weaker and tire more easily, and may even faint. The dog may also lose weight and appear pale. The systemic blood pressure (blood pressure in the body versus the lungs or heart) may also be low, while the heart rate and respiratory rate are often elevated.
Mitral Valve Insufficiency is most common in small dog breeds such as Poodles, Yorkies, Pugs, Pomeranians, Lhasas, etc
Heart murmurs can occur in both dogs and cats
