Originally Posted by oceanview916
would <muscle damage> include an enlarged heart and/or heart failure?
Muscle damage would impede heart contractions and could interfere with electric impulses and cause irregular heartbeats.
The damaged heart to compensate for weak contractions could/would enlarge and require treatment. Without intervention and proper treatment the heart pumped into circulation would eventually be reduced to an output of less than 29%, and that would be in the heart failure range.
Heart failure and an enlarged heart is not always just a consequence of a heart attack (MI). Heart failure can develop from other causes, i.e. heart valve stenosis (restricted output by a narrowed opening), valve regurgitation (some backflow of blood resulting in not enough blood getting into circulation), etc.