Which symptom suggests a need for immediate medical intervention?

Chest pain radiating to the arm is a classic symptom associated with cardiac conditions, particularly myocardial infarction (heart attack). This symptom is often an indication that the heart is not receiving adequate blood flow, which can lead to serious complications or even death if not addressed immediately. The radiation of pain from the chest to the arm, commonly the left arm, is particularly concerning and suggests that the heart may be under significant stress.

In contrast, the other symptoms listed, while they may indicate potential health issues, do not typically require immediate medical intervention. Fatigue after minimal exertion can be related to a variety of causes, including anemia or deconditioning, but it is not as urgent as chest pain. A mild headache can be common and might not signify a serious condition, and occasional dizziness can also derive from many non-critical causes. Therefore, the presence of chest pain radiating to the arm is a distinguishing factor that necessitates an urgent medical response.