The doctor, Elizabeth Trujillo Izquierdo, who was part of an elite medical team that treated Castro, said he was taken to the hospital on Oct. 22 with symptoms of hypertensive encephalopathy.

The disease often leads to strokes and partial paralysis. The symptoms include a traumatic rise in blood pressure, reducing the blood supply to the brain.

Castro, 71, was treated and placed in a hyperbaric chamber and left the hospital after six days, Dr. Trujillo said, adding that Castro had hyperbaric chambers at his home, in his office and on his plane.

Don't Get Your Hopes up! Castro looks perfectly healthy as he gives a speech on a Caribbean tour on Thursday, July 30, 1998.

Dr. Trujillo and her husband, also a surgeon, left the island in April and secretly moved to Costa Rica. She had no intention of discussing the case, she said, until suspected agents of the Cuban Government tried to abduct her on June 20.

The Herald said it had confirmed her identity, but was unable to confirm her reports about Castro's health.

The newspaper said Dr. Trujillo, 34, is a daughter of Castro's former personal secretary and a niece of the chief of the President's bodyguards.

According to Dr. Enrique Carrazana, chief of neurology at Baptist Hospital in Miami and head of the Neurological Center of South Florida, hypertensive encephalopathy is caused by the silent killer known as hypertension.

"Hypertensive encephalopathy has a high index of mortality," Carrazana said.

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