Which of these is NOT a symptom of myocardial infarction?

Myocardial infarction, commonly known as a heart attack, typically presents with specific symptoms that are indicative of the heart's lack of blood supply and the resulting damage. Among these symptoms, chest pain is the most classic presentation, often described as a feeling of pressure or tightness. Decreased blood pressure can occur due to the heart’s impaired ability to pump blood effectively, while shock can be a serious complication stemming from myocardial infarction, arising from a sudden drop in cardiac output.

In contrast, a headache is not a classic symptom associated with myocardial infarction. While some individuals may experience a headache during a heart attack, it is not considered a primary symptom connected to the heart's distress or damage. The presence of concrete indicators such as chest pain, decreased blood pressure, and shock is critical for the diagnosis of myocardial infarction, which further distinguishes this condition from general malaise or other states that might cause headaches.