my dog has problems breathing

[Leatherleaf6]

My shuh tzu is having problems breathing.  We took him to the vet and he said it's a cold.  So he is on meds and has been for about 2 weeks.  Not working.  When he has problems breathing he just shakes for he is scared what's going on.  He now will not eat, and sleeps all the time.  This has been going on for about a month now.  I was wondering if it could be his heart.  The vet didn't say anything about his heart.  He thought it was his sinuses.  But not sure about that.  Need some help.  Charlie is 9 years old, and is also on allergy pills.  Not over weight at all. Help

[Bee1111]

Let me share my experience.  My dog is shihtzu. 14 years old . 2 years ago. he has difficulty breathing.  He go upstair , try to breath and then fall down. I took him to vet for oxygen. Vet listen to heart and said it might be heart problem .When come back home, he try to breath again. So I go to vet that special on heart.  They X-ray, blood test,echocardiogram,and electrocardiography.  It concludes that my dog has heart problem.  Enlarge,arrhythmia, valvular heart disease.   Now he take 4 meds.  Vetmedin, furosic, anapril,and digoxin.  He live up until now.