Michael was with girlfriend Kate Major on Tuesday and not feeling well.
"He was short of breath all day," Major told RadarOnline.com. "His blood pressure skyrocketed. Right now they’ve told him it looks like he had a minor heart attack but they are still doing tests on him."
Lohan is at St. Francis hospital in Manhasset, New York. He is in the emergency room, according to Major, and is in good spirits and talking.
Source: Radar