Brief Answer:
Get investigated as advised

Detailed Answer:
Hello,
I have gone through your question and understand your concerns.
Memory loss in congestive heart failure occurs due to hypoxic injury due to decreased oxygenation of brain.
However at this age, age related memory deficit can also occur and needs to be evaluated.
Other secondary causes of dementia like hypothyroidism, vitamin B 12 deficiency, renal dysfunction or liver disease can also be a cause.
Blood investigation including Thyroid profile, vitamin B 12 levels, renal function test and liver function test should be done.
Treatment like donepizil, memantine or rivastigmine can be added.
Hope you found the answer helpful.
Regards
Dr N Kumar
Neurologist

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