Her agent, Mike Church, says the 69-year-old singer had been scheduled to perform Wednesday night with Neil Sedaka at The Capital One Bank Theatre at Westbury, L.I. Instead, she was taken to the hospital with dangerously high blood pressure.
Francis, who recorded '50s and '60s pop hits including "Who's Sorry Now?" and "Lipstick on Your Collar," had been expected to leave the coronary care unit Friday.
Church says that although she is "doing well," doctors decided she should remain in the hospital for observation for at least another day.