He has been kept under observation at the intensive care unit (ICU) of the Cardio-Neuro center of the hospital.
On learning of his health, Prime Minister Narendra Modi, Home Minister Amit Shah, and other BJP leaders visited the hospital.
The premier medical facility put out a statement around 8:45 PM, revealing Jaitley's condition.
"He is currently undergoing treatment in the intensive care unit under the supervision of a multidisciplinary team of doctors. At present, he is haemodynamically stable," the statement read.
Being hemodynamically stable means that the force at which heart should pump blood is fine.
Reportedly, Jaitley was admitted around 10:30 AM.
Jaitley's health is being monitored by a team of doctors, including, endocrinologists, cardiologists, and nephrologists.
Among those who visited the 66-year-old at AIIMS were PM Modi, Shah, Defense Minister Rajnath Singh, Lok Sabha Speaker Om Birla, Health Minister Harsh Vardhan, Finance Minister Nirmala Sitharaman, Minister of State for Health Ashwini Choubey, and BJP working president JP Nadda.
Sharad Yadav also paid a visit.
Jaitley had taken a long break after a kidney transplant last year, and his health has remained a major concern.
Earlier this year, Jaitley, who is diabetic, flew to the US for medical treatment. As a result, he couldn't present the final budget of PM Modi's first term.
His colleague Piyush Goyal stepped in his shoes and presented the budget in February.
In fact, Jaitley was admitted to AIIMS in May this year too.
After PM Modi steered BJP to a historic win in 2019 elections, Jaitley wrote a letter asking to be excused from the cabinet.
The lawyer-turned-politician, who is among BJP's most important troubleshooters, told PM Modi that he has faced some serious health challenges in the last 18 months.
"I am writing to you to formally request you that I should be allowed a reasonable time for myself, my treatment and my health and therefore, not be a part of any responsibility, for the present, in the new government," Jaitley had written.
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