Serbia’s President Aleksandar Vucic has cut short a visit to the United States and returned to Serbia after feeling sudden chest pain apparently caused by high blood pressure, doctors said on Saturday. Vucic, 55, suddenly fell ill during a meeting in the U.S. on Friday and decided to return home against the advice of U.S. doctors, said cardiologist Dragan Dincic, from Belgrade’s Military Hospital, where Vucic was treated upon arrival.