What Could Be Causing Continuous Belching, Suffocating Feeling And An Inability To Sleep After An Angioplasty To Manage A Heart Attack?

Hi, my friend who’s 34/ M •History - had heart attack 5 months back, got his angioplasty done with 2 stents. After coming home he got high fever and got diagnosed with typhoid and got hospitalised again. Then again in a week he had Ventricular Trycardia attack and again went to hospital. Now from last 2 months it was okay but it’s been a week he’s burping and burping. He is taking antacids, eno and what not but he can’t sleep. Been two days he’s burping like a normal person breathes. Last night he couldn’t stop his burp and he felt he is suffocating. Ps: he’s not eating too much food, ever since he got his angioplasty done he again and again had issues and couldn’t walk. So basically he’s not in a position to go for a walk or even exercise. Too much worried about what should be done. Please help us.