I always expected Chris to die by somehow accidentally dropping an entire building on top of himself or setting himself on fire by mistake or something. If he dies of a heart-attack, it would be a pretty uninspired ending considering his life... although I must say that it does sound like the more realistic outcome thoughSounds more like heart burn.
Plus he has a family record of cardiovascular issues (Bob). I think Chris himself used (still uses?) cholesterol-controlling medication.Chris is old, fat and does not exercise at all, not even as little as playing with a Wiimote or something.