He's a beautiful boy. I vol'd at our local spca and the dogs getting treated for heartworm were to remain calm. Short potty walks and no jumping. Just keep him 'snoozin' and 'velcro'd' to you. He'll be content and healing. I always have a 'soft spot' for the 'older ones'.
Sorry I have no patience for those who give up a dog after so many years. Have seen to often and just want to smack these people up side the head.