Brief Answer:
Pls do echocardiography and if required CT angio.

Detailed Answer:
Hi XXXX,
Thanks for writing in to us.

I have read through your query in detail.
It will be important to know if there is any risk of obesity and heart diseases in your family and if your obesity is due to hereditary or otherwise.

As your sugar, cholesterols, BP and ECG are normal, there is no need to worry. Heart rate of 70 is acceptable and not a concern.

Walking every day for 30 minutes is a good and healthy fitness exercise.

Since you were unable to complete the TMT due to fatigue, it will be good to evaluate the pumping action of your heart by echocardiography. This is a simple ultrasound scan of your heart and the doctor will know if your heart is pumping blood effectively and if there is any deficiency in the working of the heart valves.

Angiography is of two types
1. XXXXXXX lab angiography: In this there is insertion of a small tube through your groin or wrist all the way to your heart and a contrast XXXXXXX is injected through it to see the blood flow in the coronary arteries, the channels supplying blood to the heart.
2. CT coronary angiography: In this technique a contrast injection is given through arm and the scan images the coronary arteries as the contrast passes through it.

CT angiography is less risky and non invasive when compared to CT angiography with almost similar results.

As you do not have raised levels of cholesterol or high BP, I suggest you consult a cardiologist and get an echocardiography done. Following it you can discuss if you really need a CT coronary angiography, which is less risky.
XXXXXXX lab angiography is not required if you do not have any symptoms of heart disease on echocardiography.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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