In which condition do elevated cardiac iso-enzymes generally not occur?

Elevated cardiac iso-enzymes, such as troponins and creatine kinase-MB (CK-MB), are biochemical markers that are typically released into the bloodstream when there is damage to the heart muscle. In the case of Congestive Heart Failure (CHF), while some degree of myocardial stress or damage may occur, it does not necessarily correspond to significant elevations in cardiac iso-enzymes. This can be attributed to the nature of CHF, which often results from chronic conditions that put strain on the heart rather than acute damage that leads to the release of iso-enzymes.

In contrast, acute conditions such as Acute Myocardial Infarction, Myocarditis, and Cardiogenic Shock commonly result in the release of cardiac iso-enzymes due to acute injury or inflammation of the heart muscle. In these cases, the myocardial cells are damaged to a point where they leak these proteins, which can then be detected in the blood, serving as indicators of the underlying cardiac distress. Therefore, CHF stands out as a condition where elevated cardiac iso-enzymes are generally not expected to occur.