Jayalalithaa's condition extremely grave: London doctor Richard Beale

''Jayalalithaa's condition is extremely grave," Richard Beale, a London-based doctor who is assisting doctors at Apollo Hospital in Chennai, said on Monday.

Chennai: Tamil Nadu Chief Minister J Jayalalithaa continues to remain critical despite best efforts by the doctors attending her at the Apollo Hospital here.

''Jayalalithaa's condition is extremely grave," Richard Beale, a London-based doctor who is assisting doctors here, said on Monday.

"The situation is extremely grave but I can confirm that everything possible is being done to give her the best chance of surviving (the cardiac arrest)," Beale said in a statement.

Beale, from the London Bridge Hospital, has been regularly consulted by doctors at the Apollo Hospitals here ever since Jayalalitha was admitted in September.

Earlier, a brief statement from the hospital said the AIADMK leader, who suffered a cardiac arrest on Sunday evening, "continues to be very critical and is on ECMO and other life support systems".

ECMO or extra-corporeal membrane oxygenation is a life support system used for patients with life threatening heart or lung problems. 

Apollo said the 68-year-old Jayalalithaa, who has been in hospital since September, was being treated and closely monitored by experts.

Meanwhile, thousands of her supporters have gathered outside the Apollo Hospital since Sunday evening as news that Jayalalithaa had suffered a cardiac arrest spread like wild fire.