Hello! Welcome and thank you for asking on HCM! I understand your concern and would recommend consulting with your GP for a careful physical examination. Your symptoms may be related to a pinched nerve or a vascular disorder. A nerve conduction study (electroneurography) is necessary to rule in/out possible pinched nerve, which could cause these symptoms. From the other hand, a Doppler ultrasound is needed to examine better the blood flow in the arm vessels. Some blood lab tests ( complete blood count, PCR, sedimentation rate) are needed to exclude possible vessel inflammation (vasculitis). Hope to have been helpful! Feel free to ask any other questions, whenever you need. Greetings! Dr. Iliri