|MadSci Network: Zoology|
The average heart rate is 80-120 beats per minute. Dogs that are very fit have a lower heart rate than dogs that are not fit. When a dog breathes, the heart rate will increase and decrease with each breath, so don't be concerned if the beat is not 1 and 2, 1 and 2, 1 and 2, it may be 1 and 2, 1 and-a 2, 1 and 2, 1 and-and-a 2. It usually takes a trained ear to hear a heart defect. If your dog had an abnormal heart beat that was so obvious anyone could hear it, then his condition would most likely be quite severe and he would be showing outwardly signs of heart trouble, like; shortness of breath, low tolerance of exersize, and fatigue. At 12 years of age, I would be more conserned about the condition of his kidneys and liver. There are simple blood tests that can be run on older dogs to check the function of these organs. Heartworms can be a serious disease for dogs that affects the heart. Depending on where you live, the chances for contracting the disease may be great or slim, but there is always a chance - no matter where you live or what kind of dog you have. I recommend when he has his yearly heartworm check, that the veterinarian draws a little additional blood and checks the kidney and liver function as well. Here is something I found on the internet about heart murmurs. It is specifically discussing human defects, but since the dog and human heart are very similiar, it is applicable to your dog: A heart murmur is a swishing or a whistling sound that the doctor hears when he listens to your child's heart with a stethoscope. The heart beat normally makes two sounds: the first is Lub and the second is Dub, these two sounds follow each other (Lub Dub) and are not separated by any extra sounds. A heart murmur will be heard as a swishing or a whistling sound in addition to the normal Lub-Dub sound. The moving blood sounds like the running water in your garden hose. A heart murmur may indicate that there is a heart problem or may be due to normal blood flow. A heart murmur is not a diagnosis or disease, it is a sign to alert our attention to check if there is anything wrong. Most of the time heart murmurs are normal and do not indicate that there is anything wrong with the heart. However, sometimes they may result from a hole in the heart or a narrowed valve. A hole in the hose allows water to squirt out producing a whistling sound. Heart murmurs come in different sounds which may help indicate whether the murmur is normal or abnormal. Click the sound icon http://www.childrenheartinstitute.org/educate/murmur/ murmur.htm to listen to the different heart murmur sounds on this page. Thank you for the question and thanks for taking good care of your pet!
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