Macri, 57, suffered from a "light arrhythmia" at around 3 PM local time, but he carried on working normally at the presidential residence in the outskirts of Buenos Aires, his office said in a statement yesterday.
He was checked into a hospital at around 7:30 PM for precautionary studies. He was released later in the evening.
Macri took office in December vowing to revive Argentina's economy and root out corruption. The former Buenos Aires mayor is credited with ending a long-standing legal dispute that recently returned the South American country to international credit markets after nearly 15 years.
Macri, who has also been president of one of Argentina's top soccer clubs and is the son of one of Argentina's wealthiest persons, says the companies were family businesses and he was a figurehead without compensation.