Brief Answer:
Needs investigation. continue medications now.

Detailed Answer:
Hi Thanks for using XXXXXXX
I went through the query and understand your concern.

Carotid artery narrowing may be the cause for your giddiness.

You have got done the MRI angiogram a year back. Now the statue might have changed. Get done duplex USG/ Doppler scan at both carotid artery to know the status and you may require magnetic resonance angiography.
If calcification has occurred at the site of narrowing then further narrowing is rare and if not calcified the chance of getting embolism is there.

Since you have severe giddiness I advice you to get the above said investigation along with lipid profile, blood sugar level and complete haemogram. Based on the investigation report we can manage the cause for giddiness.

You need to take drugs for hypertension, hyper lipidemia, diabetes (If suffering) and have to quit smoking (If smoker). Continue anti platelet drugs.

If the giddiness is due to carotid narrowing (diameter of the lumen of the ipsilateral XXXXXXX carotid artery is reduced more than 70%) and if the problem is very severe then you can consider carotid endarterectomy (CEA). If the narrowing is 50-60% then continue medical treatment. 60-70 % narrowing then may select stenting or can continue the medical treatment.

For now continue drugs you are taking and get done the investigations explained earlier. Based on results and examination further management can be decided.

I hope this information has been both informative and helpful for you. Feel free to ask if any related query and I will be glad to answer them.
If you like my answers kindly rate it, and write a review as well.
Wish you a very happy life and good health.

Regards,

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