Possible reason for death

Question
Hello Dr.Fry,

 I'll try to get to the point and not waste to much of your time..My girlfriend (Lynn) and I had left for the weekend and prepared extra water and food for our Cat Romeo along with a clean litter box..We were gone for 3 days and when we returned we found the food untouched and Romeo not at the door to greet us..Lynn found Him on his fuzzy blankit in the spare room on his side with his legs out and eyes open..Looked like he was just relaxing..But,he was stiff as a board and very dead..Romeo was about 4 years old a male and was always in great health..He was a Persian,pretty blue eyes and sweet as could be..Before I moved him I took a very good look at him..His body was neat and clean,his mouth and butt were clean his eyes looked good..I felt all over him and found no bites or anything unusual..He looked in perfect condition thou the room had started to pick up a bit of a foul scent..I think by the smell of the blanket he was on his bladder must have released itself..Also when I picked him up to move him a redish mostly clear fluid streamed out of his nose,maybe a teaspoon or so in amount..Best I can tell he must have died the day we left because his food was untouched..I fed him the morning we left and he ate and did as he always does..The only thing I can tell you is the night before we left,it was about 3am and he was walking around kind of youling in that throaty way they do sometimes..And he does that from time to time when he wants to get out late at night..
All I'm asking is for your best guess as to what you think may have happend..Lynn did not want to take him to a Vet he was stiff as a board and already dead so I burried him very shortly there after on a hill behind our house..

Thank you for your valuble time and response.

Bruce And Lynn from NC

Answer
Hello Bruce & Lynn.

Usually with sudden death it is from heart disease.  And in cats, heart diseae often goes undiagnosed and the first symptom is sudden death.  Cats get a form of heart disease called hypertrophic cardiomyopathy, where the heart wall thickens and causes less blood to flow into the heart than normal...many cats will not have a heart murmur but just an elevated heart rate with this type of heart disease.

Was there any urine on the blanket?  If not, the other thing is that he may have possibly died from a urethral blockage.  But without an autopsy, it is just speculation.

So Sorry for your loss,
Dr. Fry