Can a heart murmur be deadly? also, could that person with a heart murmur have a heart attack?

Let me clarify: All a heart murmur is is a sound. It's like, "can a train horn be fatal?" some murmurs are innocent. Some are indicative of an acute, dangerous deterioration in the heart. When people have heart attacks, they may or may not have a pre-existing murmur: no relationship. When someone develops a new and loud murmur in the setting of a heart attack, it may mean something very bad has happened.

Yes: Critical aortic valve stenosis. Severe mitral regurgitation and some others. Yes, sudden death and heart failure are causes. Embolism to coronary or poor flow in he presence , or rarely without, coronary disease.Complex situations need cardiology to help pick the significant murmurs and treat or refer to cardiovascular surgery.