Hello! Thank you for asking on HCM! Regarding your concern, I would like to explain that is seems most probably to be an expression of nightmares (which is a kind of sleep disorder more typical for individuals of your age), associated with vegetative abnormalities, like abrupt sinus tachycardia, etc. There is nothing to worry too much! They are harmless. Nevertheless, I do encourage to have a medical check up (physical exam, a careful neurological status review, including your sleeping, resting ECG, etc). Besides your scheduled cardiac ultrasound, I would recommend an ambulatory ECG monitoring if those complains become frequent (almost daily), to exclude a possible associated cardiac arrhythmia. Also a pulmonary function test, coupled with an arterial blood gas analysis would be necessary to exclude possible hypoxemia during sleeping. Hope to have been helpful! Greetings! Dr. Iliri