I took Miko from emergency to his regular vet this morning. After a series of xrays and reviewing the blood work our vet recommends a drug treatment plan for the time being rather than surgery. He will be on heart medication and diuretics for the next short while. Our vet believes he is seeing an enlarged heart and high blood pressure in Miko that is leading to fluid leakage. This is a better result than I was expecting. Thanks everyone for your good thoughts - you may have helped in a miracle for my sweet boy.