beta
I think our MC has suicidal tendencies bc of his low self worth. I think he had them before his heart operation and still has them. One of the most common forms of this that isn't the obvious like actually trying to kill ur self, is reckless behavior.
It's Passive Suicidal ideation, he has nothing to live for and feel like a burden so the idea of doing dangerous thing like this doesn't bother him. For him it seem he made this choice because he will either succeed in helping them or he will die doing so. This makes him feel like his life is worth something until he does die. More evidence is how willing he was to let himself drown. And I have a feeling the accident he was in that got him the heart transplant was likely caused by this behavior as well.