It may seem like he is depressed but it may actually be the body still recovering from the attack. I thought my grandfather was depressed too but he actually had congestive heart failure after a heart attack. He had to have weight checks every am cuz his lungs were filling with fluid and he was sleeping a lot which to me looked like depression. Part of the heart muscle may have died and so his energy may be low. He may also be having an acute stress reaction where he is overwhelmed with the processing of the near death experience and cannot tolerate too much stimulation like music. Hope you are taking care of your stress too! It's a lot to go through with diet changes, doctors appointments... Hot showers or baths, self care; some of your favorite things, people, activities.,. Hope you and he feel better!!!