Hello. Welcome to ask the doctor.
It seems that your fiance is suffering from the intervertebral nerve compression leading to the pain neck with numbness left arm.
I will advice you to get MRI spine to look for it.
By the time, do hot compresses. He can apply volini gel and take painkillers like diclofenac .
But the possibility of heart disease needs to be ruled out. Get ECG done.
I hope it helps.
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