Information and Broadcasting Minister Priya Ranjan Dasmunsi remained on life support system for the 15th day on Monday with no improvement in his health.
"His condition is the same as it was on Sunday. He is still critical and on life support system," said Dr Vineet Suri, consultant, neurology, Apollo hospital.
62-year-old Dasmunsi had suffered a severe heart attack on October 13 and was admitted to AIIMS. On October 20, he was shifted to Indraprastha Apollo Hospital for further neurological treatment.
Diagnosed of a complete failure of the left ventricular system, his condition resulted in swelling of the lungs.
As a result there was reduction of oxygen supply to the body parts, known as hypoxia, which is the main complication in such conditions.
"In the case of Dasmunsi, brain stopped getting sufficient oxygen supply resulting from oedema damaging some of the neurons responsible for key functions of the body," doctors at AIIMS said.
The shortage of oxygen supply to neurons causes a cascade of abnormal events in the body. The neurons can suffer temporary dysfunction, or there may be irreversible damage to nerve cells, they explained.
"In his one week stay at AIIMS, Dasmuni showed no movement of the four limbs and his pupils remained fixed and dilated," the doctors said.
American neurologist from John Hopkins University, Dr Den Henley, was flown in last Saturday to examine Dasmunsi. He conducted an EEG of the brain to look for any further scope of treatment.
"Currently his neurological condition is being closely monitored," said a doctor at Apollo.