Which choice will lead to an early grave?

[Negativedarke]

Hisao's heart condition only ever comes up on Lilly and Hanako's routes. I would assume that he's still getting proper exercise and diet on the other girls routes. In Lilly's case he did neglect his exercise, and at times medication, and he did end up suffering another heart attack. I suspect from there on out Lilly will try to make sure he takes better care of himself, but the damage may have been done. In Hanako's case, it's partly due to not exercising as much, and I imagine partly because it covers the least amount of time, and he may not be as far along in his recovery.

[Charmant]

Lilly would be most likely to trigger an attack. Rin would be most likely to fail to help during an attack.

[Taotao]

From what I've played, it seems like Lilly is the most aware of Hisao's health and concerns herself with it the most often of all the girls. In her arc, pretty much every time his heart had a problem it was because of something he'd done without her knowledge. For instance, while it might have been foolish for her to expect him to "take charge" as she puts it in the last sex scene, she realized it was beyond his capabilty, but only after he put himself in danger because he didn't want to let her down and seem weak when he knew it was coming. Another example is when he forgot his medicine.
It seems like she would be the best at pinpointing potential triggers for it and avoiding them at all costs, making sure he takes his medicine, not over exerting himself, etc. She seems to care the most. She'd be like a second mom when it came to his health.

[Eurobeatjester]

I always saw that as more plot that was intrinsic to the story as opposed to something that reflects on his actual condition. Lilly's sex scenes have her doing all the work, and when Hisao tries to take charge, or even reciprocate as equals in bed, his heart acts up. This isn't the case with some of the other sex scenes in the game. You could say that his health improves enough with Emi's coaching to not be an issue, but it's not a problem with Rin, Shizune, or Misha, although there's a heart flutter at the end of Hanako's scene. It just seems that the writers decided to keep Hisao deliberately weak in Lilly and Hanako's routes for the sake of the story.

That's perfectly fine, but it's hard to base ideas on since the Hisaos present at the end of each route are different people, mentally and physically.

[Munchenhausen]

Hisao's heart condition only ever comes up on Lilly and Hanako's routes.

Are you forgetting Emi exists, too?

Lilly would be most likely to trigger an attack.

Care to elaborate?

Rin would be most likely to fail to help during an attack.

No elaboration needed.

[Oscar Wildecat]

Rin would be most likely to fail to help during an attack.

Abstract 128: More Effective Chest Compression and Less Rescuer Fatigue in Cardiopulmonary Resuscitation with Leg-Foot Compression with a Footstool, Hamamatsu Univ Sch of Medicine, Hamamatsu, Japan. Now we know where Hisao and Rin went to college.

[brythain]

Rin would be most likely to fail to help during an attack.

Abstract 128: More Effective Chest Compression and Less Rescuer Fatigue in Cardiopulmonary Resuscitation with Leg-Foot Compression with a Footstool, Hamamatsu Univ Sch of Medicine, Hamamatsu, Japan. Now we know where Hisao and Rin went to college.

Headcanon—that's where Kenji's uncle, the Black Dragon, teaches...

[Eurobeatjester]

I just got a mental imagine of Rin jumping up and down on Hisao's chest, attempting to perform CPR

[Taotao]

Care to elaborate?

I think what was being implied is that Hisao's health and responsibility about it is really lacking in Lilly's route, and he had the most close calls with her
Also, Lilly is the most frisky, it seems. That would be bad for anyone's heart.