Two years after she underwent surgery at New York’s Sloan-Kettering Centre, Congress president Sonia Gandhi left for the United States on Monday afternoon for a scheduled medical check-up, accompanied by her daughter Priyanka Gandhi Vadra, official sources said.

Ms. Gandhi has been to the U.S. twice in between — in February and September 2012 — for routine check-ups.

With Ms. Gandhi still the real head of the Congress — even though the transition to hand over power to her son, Rahul Gandhi, has begun — concerns about the state of her health in party circles remain: last week, it was Ms. Gandhi who led her party’s discussion on the landmark Food Security Bill, and was able to pump some energy into a party disheartened by scandals and a battered economy.

Indeed, exactly a week ago, the Congress president gave her party colleagues a scare when she complained of chest pain and exhaustion during the voting on the Lok Sabha debate on the Food Security Bill. Accompanied by Union Social Welfare Minister Kumari Selja and Mr. Gandhi, she was rushed to the All India Institute of Medical Sciences, where she was first admitted to Emergency.

However, tests at the hospital’s cardiac care unit later indicated she was alright: it was just that she had been suffering from viral fever and had been given medication that she reacted badly to. She was discharged from the hospital later, returning home at around 1.30 a.m. — but not before panicky Congress leaders made a beeline for the hospital to enquire about her health.

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