Hello Doctor my father passed away just few days back but we are unable to know the cause of his death. The morning he passed away, night before we had taken him to the hospital as he was complaining of cheat pain, but hospital did eco and blood test to detect heart issues but a reports were normal, so we took him back to our home. But after two hours he was completely breathless and was complaining about severe pain. He changed his clothes by himself and walked by the stairs case and even walked to the hospital after getting out of the car. Hospital administered oxygen but he passed away within minutes. Please sir help me to understand his cause of death, he had blood sugar and one year back he had undergone operation to fix pacemaker and stents.