Caught it during my yearly physical. She ordered a routine EKG (I am age 60) so she would have one on file for a baseline, and it showed a left brachial branch block (an electrical distribution issue in the heart). I had no symptoms.

She then ordered an echo cardiogram which revealed the left ventricle atrophy. She then ordered a sleep study because sleep apnea can cause heart issues and the diagnosis was mild sleep apnea and central sleep apnea.

That is how it was found out because I had no symptoms.