Can a puppy's sibling pass on a heart murmur if they don't have it?

It depends on the cause of the enlargement. If it is something that just malformed by chance then it may be a rare occurrence only affecting one puppy. Other times it could be a genetic issue and more than one puppy could be affected. However I would recommend getting the whole litter examined to ensure no one else is affected.

Thank you for submitting your question regarding your potential new puppy. Young puppies can occasionally have what is known as an innocent murmur. This is a heart murmur they will outgrow usually by 6 months of age and is not associated with any ongoing disease. Other murmurs are associated with congenital heart disease and go on to cause the puppy significant disease. I recommend having the puppy evaluated by a board certified veterinary cardiologist. A procedure known as an echocardiogram will likely be needed to assess for any structural heart disease. This will give you the longterm prognosis for the puppy. I hope this information helps!

Most puppies with grade 1 heart murmurs have these due to physiologic changes that they grow out of. However, there are some heart conditions that can start as a grade 1 murmur which can progressively worsen over time. Odds are in your favor that Nelson would grow out of this murmur and that it is insignificant. There is always that off chance that he has a more severe condition. Consider asking the breeder to include progression of heart disease (indicated by a worsening murmur) in the contract, in that if it does progress, you could return Nelson (unless you believe that you will get too attached). This is not an easy decision without a definitive right or wrong answer.

Most dogs with a heart murmurs are fine and symptom free, there is no way to know for sure but when she is a little older you can ask your vet to refer you to a cardiology specialist to have a few tests done to check if her heart is in healthy condition.

Thank you for submitting your question regarding Soren. A heart murmur is due to a leaky valve in the heart allowing blood to flow in the wrong direction. I typically recommend having x-rays taken of the chest to evaluate the heart and lungs. I will a lot of times recommended an ultrasound of the heart knowns as an echocardiogram as well. I refer my patients to a cardiologist for this procedure. Being a young dog, the murmur could be due to a congenital defect. A lot of times, the results are great and the cardiologist informs us that the murmur is nothing that we need to worry about in the future. If there is a concern though, it is best to know about sooner rather than later. I hope this information helps!

This is common and generally they do grow out of it. Norwich Terriers are not at high risk for heat disease. I don't know of any statistics on this. If the murmur persists a grade 1/6 is very mild and would not require treatment. Generally a grade 3 or higher may need medication to improve the heart function and reduce fluid in the lungs. Most dogs with heart murmurs live long lives with minimal issues. Personally I would adopt the puppy anyway as I would not expect it to progress or effect the dogs quality of life. To be safe you may want another veterinarian to examine the pup and listen also. It's always a good idea to get a second opinion. Thanks for using Petco Pet Education Center, formerly Petcoach to help you get answers to your veterinary questions.

20-40% of adult Cavalier King Charles Spaniels have heart murmurs, most commonly due to hereditary problems with the mitral valve. While many go on to develop congestive heart failure, other dogs may be asymptomatic for a long time, or may develop another disease before the heart is significantly affected. Not all Cavaliers die from heart disease.