Pick the wrongly matched pair

The correct answer is cardiac arrest – narrowing of lumen.

Let us analyze each pair to understand why "cardiac arrest – narrowing of lumen" is wrongly matched:
1. Heart failure: This is a state of the heart when it is not pumping blood effectively enough to meet the needs of the body. Thus, "heart failure – not enough blood supply to the body" is a correct match.
2. Angina pectoris: Also known as "angina", this is a symptom of chest pain or discomfort that occurs when the heart muscle does not get enough oxygen-rich blood. It manifests as acute chest pain. Thus, "angina pectoris – acute chest pain" is a correct match.
3. Heart attack: This occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or cut off completely, usually due to a blockage in the coronary arteries. Thus, "heart attack – not enough blood supply to cardiac muscles" is a correct match.
4. Cardiac arrest: This is a condition where the heart suddenly and unexpectedly stops beating. It is an electrical issue in the heart, not primarily defined by the narrowing of the blood vessel lumen (which is a characteristic feature of Atherosclerosis or Coronary Artery Disease). Therefore, matching cardiac arrest with "narrowing of lumen" is incorrect.

Hence, the wrongly matched pair is "cardiac arrest – narrowing of lumen".