I don't blame you for being nervous and scared about learning you have HOCM.
I was too, and feared I would die on some days when my symptoms were so bad.
You are doing the right thing by being seen by an specialist for sure. This is an elusive condition and can take years to be correctly diagnosed. I was 61 when I learned what I had and 62 when I had open heart surgery. I have never regretted or looked back after having the surgery. It saved my life and gave me back the ability to do what I had lost...like hiking and walking our local trail system every day.
I'm glad your appointment is so quick, that will hopefully help you know your options and get a plan going forward. Have you made a list of questions yet, or will you do that after reading up some more?