Brief Answer:
Thallium perfusion scan is alternative , angio is safe in experienced hand

Detailed Answer:
Hello Sir, I am Dr. Mody and I will be addressing your concern .
Firstly I do Under the risk factor as being 61 yr male who is hypertensive, diabetic and hyperthyroidism.
Now the concern here is
1) treadmill mill test you could achieve less than 5 Mets or less than 5 mins, you haven't mentioned. However in both circumstances it's less than desired for your age, so was the reason for termination fatigue, tiredness, breathlessness or chest pain or doctor terminated because of some changes Also do upload the test so I can interpret for you
2) the blood pressure in two arms are different.
Possible mechanism some block in one arm, or diffuse arteriosclerosis in the arm which is very common in diabetes.
Again both pressure are high and should be treated with optimum anti hypertensive
.
Now you haven't mentioned which angiogram, however I will presume it as coronary angiography for Indication 1, as for 2 a good doppler sonography may help to delineate the blocks and you don't need an angiography , however for your heart if treadmill test is positive and you having all the risk factor an angiogram is justified.

So as such angiogram is very safe in experienced hand and the only drawback is the XXXXXXX used which may harm your kidney particularly when they are weak because of long standing diabetes and hypertension. However proper pre op assessment and hydration with necessary precautions will be good enough to prevent the same.
An alternative non Invasive test after treadmill is thallium perfusion scan, which is very safe, less than 1 ml of contrast and would give adequate information for next step.
Sir a more detailed history and uploading of reports will help me guide batter.
Regards Dr Priyank Mody, Lilavati Hospital. XXXXXXX

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