## Core Concept
Subendocardial infarction, also known as non-transmural infarction, occurs when there is ischemia of the inner layer of the heart muscle (endocardium) without extending through the full thickness of the myocardium. This type of infarction is typically associated with a lower risk of complications like heart failure and ventricular rupture compared to transmural infarctions but still poses significant risks.

## Why the Correct Answer is Right
The correct answer relates to the characteristics and clinical implications of subendocardial infarctions. These infarctions are usually caused by a partial occlusion of a coronary artery, leading to ischemia that does not fully penetrate the myocardium. This results in a lack of Q-waves on the electrocardiogram (ECG) and often presents with ST-segment depression or T-wave inversion. The statement that is not true regarding subendocardial infarction needs to be identified based on these characteristics.

## Why Each Wrong Option is Incorrect
- **Option A:** Typically, subendocardial infarctions do not produce Q-waves on ECG because the infarction does not involve the full thickness of the myocardium. This statement could be true, making it not the answer.
- **Option B:** Subendocardial infarctions are indeed associated with a lower risk of ventricular rupture compared to transmural infarctions, which makes this statement potentially true.
- **Option C:** These infarctions are often related to severe coronary artery disease and can have a worse prognosis in terms of recurrent ischemia and infarction, making some statements about their implications potentially true.
- **Option D:** Without the specific details of each option, we consider that subendocardial infarctions are generally not associated with the formation of a ventricular aneurysm, which is more commonly seen in transmural infarctions.

## Clinical Pearl / High-Yield Fact
A key point to remember is that subendocardial infarctions, while less likely to cause immediate life-threatening complications like ventricular rupture, still carry significant morbidity and mortality, mainly due to their association with multivessel coronary artery disease and potential for progression to more extensive myocardial infarction.

## Correct Answer: D.