Thanks for your query.
I recommend you to visit the ER now.
The symptoms your husband has might be due to Hypoglycemia
(Low blood sugar
). Is he a diabetic - if yes, there are high chances of hypoglycemia. Else, the second possibility of gastrointestinal infections causing loose stools needs to be ruled out.
Both hypoglycemia and frequent loose stools associated with dehydration
can present with the aforementioned features. If untreated it is not safe for a person with heart conditions.
Therefore I suggest him to visit the ER soon. His general hydration status and blood sugars need to be checked and corrected if abnormal.
In the meantime, do give him rehydrating solutions like juices, plenty of water now and on the way to the ER.
Hope this answers your query. I wish him a speedy recovery. Do let me know if there other concerns.