Brief Answer:
CHF is the cause, Pred Should be avoided.

Detailed Answer:
Dear Friend.

Welcome to HCM. I am Dr Anshul Varshney. I have read your query in detail. I understand your concern.

Since he is suffering from Congestive heart failure (CHF), so probable reason for his pedal edema is CHF only.

Moreover, he is on Prednisolone that increases the water retention and pedal edema.
I would like to know following details to help him better:

1. On what medications he is on for CHF.

2. What valve problem is he having? I suppose you are talking about Low Ejection Fraction.

3. For what purpose he is on Prednisolone and at what doses.

A person, who has sleep apnea and CHF, should not be ideally treated with steroids, because steroids worsen the condition. So, there must be some strong indication for that he has been prescribed steroids.

4. What are his current blood pressure and blood sugar levels?

5. Is he mobile? Or bed ridden?

6. Is he breathless also?

This is my best advice for you based on available details. If you have any further query please ask me and revert the asked details preferably in point wise manner for a better help.
Stay Healthy.
Dr Anshul Varshney, MD

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