Sampson's Cardiology Appointment

My dog Sampson is a 4 year old terrier mix. I rescued him from the Humane Society when he was only a couple months old. He's been a healthy pup up until these last couple weeks. It started with him urinating on my bed and other furniture. He's a very well trained dog and it's unlike him to do something of that nature. He's also been having some lethargic spells where he doesn't eat much. When these things started happening more, I noticed he was losing consciousness during his episodes. I was able to get Sampson into the vet after he'd fainted 3 times in one day. To my surprise, I learned that he was anemic but that didn't explain why he's been losing consciousness. Sampson was then reffered to a specialty vet clinic. After doing numerous tests the conlcusion was he must be having some sort of heart issues. In order to figure out exactly what's going on Sampson needs to see a cardiologist. The cost to have the appointment will range from $700-1,000. I've been able to cover the cost of everything up until now. The appointment will need to be made in about a week. So, I need your help. I don't have a lot of time but any amount of donations would be a blessing. Sampson is extremely precious to me; he's my baby. Any of you dog moms/dads out there understand that. I want my Sampson back to his crazy, hyper, full-personalitied self. Feel free to email/message me if you have any questions.