Former Finance Minister Arun Jaitley was admitted to the AIIMS in Delhi on Friday after he complained of palpitations and restlessness, and is under observation, news agency PTI quoted sources at the hospital as saying.
Jaitley, 66, was admitted to the Cardio-Neuro-Centre of the hospital around 10 am, they said.
Doctors at AIIMS said that Jaitley is currently undergoing treatment in the intensive care unit under the supervision of a multidisciplinary team of doctors.
"At present, he is haemodynamically stable," doctors said.
"He is under observation. A team of doctors including endocrinologists, cardiologists and nephrologists is monitoring his condition," one of the sources said.
Prime Minister Narendra Modi, Home Minister Amit Shah, Lok Sabha Speaker Om Birla, Union Health Minister Harsh Vardhan and Minister of State for Health Ashwini Choubey are at the hospital to enquire about his health condition.
In May this year, Jaitley was admitted to the AIIMS for treatment.
A lawyer by profession, he has been the most important leader in Prime Minister Narendra Modi's Cabinet during his first tenure and often acted as the chief troubleshooter for the government.
Jaitley had undergone renal transplant on May 14 last year with Goyal filling in for him at that time too. Jaitley, who had stopped attending office since early April 2018, was back in the finance ministry on August 23, 2018.
Earlier in September 2014, he underwent bariatric surgery to correct the weight he had gained because of a long-standing diabetic condition.
(With inputs from PTI)