I'm sorry that you had to reschedule his appointment. If I had taken my Sunny to my vet for further tests for his hear murmur, she said that it would take at least 30 minutes and I think she said that he would have to be sedated. They would take his blood pressure and then look at his heart with an ultrasound machine. She never said anything about taking x-rays which should be much faster. I hope that everything goes well on the 18th.