Final answer:
A common complication of a myocardial infarction is aneurysm formation, which is the bulging or ballooning of a blood vessel wall. This occurs due to weakness in the arterial wall and can affect the functioning of the heart.
Step-by-step explanation:
One of the most common complications of a myocardial infarction is aneurysm formation. An aneurysm is a bulge or ballooning in the wall of a blood vessel that can occur due to weakness in the arterial wall. Following a heart attack, the damaged heart muscle can weaken and stretch, leading to the formation of an aneurysm. This can cause further complications and affect the overall functioning of the heart.