I doubt that would even be possible, maybe through lifestyle, then again, I used to smoke a shitton of cigs, especially rolled up ones with a lot of tobacco and nothing happened to me. And I'm genetically predisposed to heart issues, including strokes, yet, never suffered any. Still, I hope I could just drop dead with my heart stopping randomly, it'd be easier than CTB, people would accept my death as a random tragedy rather than being labeled as a suicide. It's understandable why some people would see the appeal in that. But aside from some niche "meditation" practices (that don't work, ofc), I don't believe it to be possible