Hi, Kelli. That is a difficult and complicated question to answer. He has severe premature coronary artery disease. There are 2 important pieces of information I would want in order to help answer your question--the most important is: What is his Ejection Fraction (EF)? That is the muscle strength number of his heart. Has he just had blocked arteries treated with surgery and stents? Or has he had heart attack damage to his heart muscle? It is the latter, not the former, that greatly reduces a person s life expectancy. The 2nd question is: At what age did his parents die? Cardiac disease and cardiac mortality seems to be hereditary, although there are many factors involved, and many more treatment advances in medicines, cardiac interventions, and cardiac surgeries between his generation and his parents generation that have improved survival for this generation vs. previous ones. One study from the Mayo clinic showed that in patients with 3-vessel cardiac disease (blockages in all 3 major coronary arteries) and a normal EF (normal is usually considered between 60-75%), the 5-year survival rate was about 90%. With 3 vessel disease and an EF between 35-50%, it was about 70%. With 3-vessel disease and an EF under 35%, it drops to about 50%. Of course, much depends on luck and medical care. Does he see his doctors regularly? Is he on standard-of-care medications that are proven to help reduce future cardiac events and/or decrease his mortality rate? These include beta blockers, statins, ACE Inhibitors (especially if he s diabetic or has had heart attacks or reduced EF), aspirin, maybe other anti-platelet drugs. Has he stopped smoking (or even better, never smoked)? Does he have diabetes (diabetics have higher death and complication rates in general and for many specific complications)? Is it well-controlled if he does? Does he have a defibrillator (AICD) if his EF is at or below 30%? As much as we know about mortality risks from chronic ischemic heart disease and chronic left ventricular dysfunction, there is much we don t understand. Two people can have the same combination of diseases, the same cardiac history, the same heart surgeries, the same EF s--and one can have severe symptoms while the other is well-compensated and has no symptoms and a much better quality of life. Even with those survival percentage graphs, we may know a percentage number, but we never know for sure who will wind up in which percentage group. All we can do is make sure the people take care of themselves, exercise regularly under the supervision of their doctor, lose weight, refrain from smoking, take the correct combination of mortality-improving medications regularly, and give themselves the best chance of doing well and surviving. The rest is up to G-d or fate or whatever. Congratulations, Kelli, on your engagement, and good luck to you and your fiancee. While these conversations are always uncomfortable, they are important, and, since you will soon be graduating from his fiancee to his wife, you have every right to open a conversation with him about it. Chances are, if he loves you enough to warn you as he did, he d love you enough to be honest about sharing with you what his doctors have told him. You could also ask him if he d mind if you accompany him to his next doctor s visit. I have plenty of patients who bring their fiancees or spouses with them. As a matter of fact, I find out most of my honest information from my male patient s wives!