What Causes Lack Of Sleep And Pain In Shoulder After A Angioplasty?

Hi, My father is 61. He had an angioplasty on 31/07/14 & two stents have been placed. After 2 days of the surgery (while admitted in the hospital), he felt a jerk while sleeping in the night/afternoon & got up from from sleep. It happened many times. While told about it to the doctor, he told it can happen because of unrest/ not sleeping well. Then he gave some medicines & it goes away. While discharged he had a shoulder pain on his right shoulder. But the Dr. said it is just a muscle pain & discharged him from hospital. They prescribed sleeping pill along with other medicines while discharging. Last night my father did not had the sleeping pill. Today morning he told that he felt the same jerk twice last night & woke up. The right shoulder pain still persists. Now the Dr. suggesting to continue sleeping pill for 1 month & apply volini over the shoulder and telling that these are not for heart issue, his heart is perfect . Please suggest me why these problems are happening after angioplasty?