In this ‘Ask the Specialist’ Q&A forum, Dr Tham Yi Chuan, Associate Consultant from the Department of Cardiothoracic Surgery at National Heart Centre Singapore (NHCS), a member of the SingHealth group, answers your questions about how best to prepare for heart surgery, what to expect, and post-surgery advice and recovery.

To submit your question, simply email it to

Please allow up to one week for your question to be answered. Do bookmark and check back this page from time to time as we will progressively add answered questions on this page.

This As​k The Specialist forum has closed. Thank you for participating.​ Scroll down to see all questions and answers submitted for this forum.

Going for a heart surgery can feel daunting.

However, taking proactive steps can help ensure a smoother experience for the operation and improve a patient's recovery process.

Whether it is you or a loved one that is scheduled for heart surgery, don't miss this chance to gather insights from Dr Tham, our cardiothoracic surgeon, on:

  1. Best ways to prepare for a heart surgery,

  2. What to expect for the operation,

  3. Post-surgery advice, and

  4. What to do to ensure proper recovery

Be sure to get the accurate answers you need about heart surgery by taking part in our forum.

Unsure what to do after heart surgery? Check out this video!


About Dr Tham Yi Chuan

Dr Tham Yi Chuan is an Associate Consultant from Department of Cardiothoracic Surgery at the National Heart Centre Singapore (NHCS). His subspecialty is pediatric and adult congenital heart surgery, and adult cardiac surgery.

Ref: I23

Questions and answers on preparing for heart surgery

1. Question by Bernard

Dear doc,

Can a person undergoing stent procedure for blockage do strenous physical exercise eg. Playing soccer, tennis,etc? If so, how long after the procedure to resume the physical exercise? Thanks.

Answer by Dr Tham Yi Chuan

Hi Bernard,

The limit of physical activity varies between patients. One of the aims of revascularisation procedures like coronary artery stenting or coronary artery bypass grafting is to improve your quality of life.  If you had undergone stenting procedure, this question would be best answered by your interventional cardiologist.

2. Question by Peter

Hi Doctor, 

How do I decide what is the right choice for heart surgery? Stenting or bypass? Thanks.

Answer by Dr Tham Yi Chuan

Hi Peter,

Depending on the types of coronary artery disease that you have, and if there is presence of other cardiac disease, the recommendation may be different. I would suggest to discuss with your cardiologist and cardiac surgeon to address your concerns and weigh the different risks and benefits before making your decision, commonly known as shared decision making.

3. Question by Siva

Hello Doctor,

I’m 45 years old. I have done my health screening including ECG and Treadmill test. All results are OK and No abnormalities. I don’t have any health issues. But some of my friends in my same age group faced heart attacks, so I’m worried.

Can I go for Coronary Calcium Scoring test? And is there any harm (like radiation) for my body, If I go for this CT scan? Thanks.

Answer by Dr Tham Yi Chuan

Hi Siva, 

I can imagine your worries. Regular health check is certainly one way we could pick up early disease and start treating them! Having a regular family physician to look after your general health and addressing your health concerns is recommended. Should you have no symptom and no other risk factors like diabetes, hypertension, dyslipidaemia, smoking or family history of heart disease now, it is less likely for you to have coronary artery disease at present.

However, if you are still worried, you could always schedule a visit with our friendly cardiologists and discuss further. 

4. Question by Wong

Dear Doctor,

NUHS recently promoted the PFA method as less scaring over traditional thermal energy method.

My question: Is PFA available or only the thermal energy method is in use in NHCS? Also how safe is thermal energy method vs PFA?


Answer by National Heart Centre Singapore (NHCS)

NHCS has introduced pulsed field ablation (PFA) since end 2022. Besides PFA technology, NHCS offers treatment methods using radiofrequency and cryotherapy ablation, with positive clinical outcomes for all 3 different technologies.

5. Question by Suan Lim

Hi Dr,

Recommendation from my Cardiologist is that I should prepare for LVAD – if my heart performance is still weak – only 215 PERFORMANCE.

Had three stents done in 2016 – NTFH

Implant of ICD single chamber in 2020

What is your recommendation please?

Answer by Dr Tham Yi Chuan

Hi Chung Suan,

Understanding your cardiac condition is the first step in taking charge of your own health, kudos to you.

There are sets of guidelines and recommendation available for treatment of heart failure. NHCS has a team of dedicated mechanical heart support specialists that include cardiologists, cardiac surgeons, allied health personnel and coordinators! If your cardiologist had recommended LVAD, you should be seen by our Heart Failure programme team, they will be able to guide you with your decision-making process.

We also have a LVAD patient support group if you would like to speak to a fellow patient to learn more about living with LVAD as well. 

6. Question by Charene

Hi Dr Tham,

My child, currently 5yrs old has ASD. In end August, he will be undergoing a procedure to insert a device. Is there anything we need to do before and after the procedure? Will there be any discomfort or things we need to take note of?

Thanks and hear from you soon.

Answer by Dr Tham Yi Chuan

Hi Chalene,

It must be a difficult time especially when we have little ones going for a procedure.

Device closure of ASD is performed by interventional cardiologists. Prior to any treatment, it is our duty to explain to you the indication of treatment and treatment alternatives and recommendation.

Device closure of ASD is usually performed via femoral catheter approach, it is a less invasive method of closing ASD. Risk and complications of the procedure should be addressed by the cardiologist. Preparation for the procedure and what to expect should be able to be addressed by the team carrying out the procedure.

Share your concerns with us and we welcome you to ask us if you have any concern as we would like to improve your experience when seeking treatment with us.

7. Question by Janice

Hi Dr Tham,

I am a female patient, 57 years old. My heart surgeon has previously diagnosed me with non-obstructive coronary artery disease, ctca shows moderate stenosis lad and mild stenosis rca. Stress echo negative for ischemia. Aim LDD at least < 1.8 mmol/L to reach 1.4mmol/L. For long term single antiplatelet agent if no bleeding issues. LDL was 4.2 came to 1.87 in Nov 21 with medication. CTCA Nov 21 shown coronary artery disease causing moderate (50 to 70%) stenosis in the LAD and mild (less than 50%) stenosis in the RCA. Calcium score 121.

May I check whether it is recommended for me to do a stenting or bypass surgery as I have tried to control my LDL with medications but not able to achieve the 1.4mmol/L?

Occasionally, I felt chest pain at wee hours and short of breath after meals. Will there be any risk if I do not do any stenting or bypass surgery?

May I know how often I should do a check on my CTCA test to review any risk on my LAD and RCA stenosis?

Thanks for your advice.

Answer by Dr Tham Yi Chuan

Dear Janice,

Kudos for taking charge of your own health!

From your description, you could be having progression of your coronary artery disease and have become symptomatic. I would suggest discussing with your cardiologist and maybe an invasive coronary angiogram would be required – it remains the gold standard of diagnosing coronary artery disease. While CTCA (computed tomography coronary angiography) is getting more sensitive over the years, an invasive coronary angiogram is mandatory for discussion of next treatment options, like revascularisation strategies such as angioplasty versus bypass surgery.

Ref: I23