Hello,
Thanks for posting your query.
Tingling numbness or loss of sensation of a limb can either be due to vascular or neuropathic problem.
However such feeling when occuring on raising the arm above heart level, most likely occurs due to a peripheral vascular disease(PVD) .
In such case the small blood vessels of the limbs do not get enough circulating blood when the arm is raised above heart level , therefore the oxygen is not supplied to the soft tissues and muscles and nerves and the toxins built up are also not cleared .Thus causing the feeling of numbness due to ischemia of tissues.
Such problems are aggravated in smokers or cardiac patients due to inherent disturbance of
circulation in their body .
The problem should be evaluated by a surgeon who after physical examination and certain investigations like angiogram, doppler studies etc can confirm the diagnosis.
The treatment would depend on the severity and usually requires medicines causing arteriolar dilation and easing the blood flow.
The earlier the problem detected and treated the better is the prognosis, and complications like ischemia , thromboembolism and gangrene can be prevented.
So as of now your condition is not very worrisome, yet definitely warrants a consultation with your physician who can evaluate and investigate you and then if indicated refer you to a vascular surgeon for further management.
Hope I have answered your query.
Regards

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