This is an autosomal dominant disease, which means you have a 50% chance of receiving it from your father and the same chance of passing it to your children, but this usually has very variable degree of penetrance, meaning it can manifest differently in different people even within the same family.
But if by adult age you have not developed HCM, then you are not likely to dvelop it and screening echocardiograms can be decreased in frequency to 3-5 years if at all.
One more thing. If you somehow determine through genetic testing that you do not have the mutation, then you can be sure your children do not have it. It does not skip a generation. If you don't have it, you cannot pass it on. Therefore, your children will not have to be tested. I am not sure I want the genetic results on my children yet, but i am pursuing the testing so that my sister can determine if she is a carrier. If not, she can stop testing her kids. The way I understand it, they identify the exact location of the mutation in my DNA and then they can look at that location in my sister's DNA for the same anamoly. If it's not there, she's good.
It is hereditary, but keep in mind that it is a gene mutation. Mutations can happen on their own as well. I have HOCM and my father did as well. He passed at 41. I was diagnosed at 30, but I benefit from better technology than was available to my father. I have an implanted difibrillator as a safety precaution and take several meds. I also had an alcohol ablation procedure to reduce the obstruction. I get annual testing to track the progression of the disease. My children get screened every three years. So far, so good. Genetic testing is available, but it is a slippery slope. What does one do with the information? Without DNA from your father, you cannot benefit from the genetic testing. Therefore, you will need to be tested periodically. Like the Doc said, you and your siblings have a 50% chance of having it as well. But if you do, there are varying degrees ranging from no symptoms to very problematic symptoms. Regardless of symptoms, there can be risk of sudden death heart attack. That is what happens to many of these athletes that collapse. They had no symptoms and therefore were never tested. Had they been tested, an abnormality would most likely have been seen or heard. My advice is to keep in shape, eat right, and get tested periodically. I would also not run any marathons or engage in super-strenuous aerobic activity as a precaution. No marathons! I wish you the best.
Is this always genetic or can you get it from other things that aren't genetic?