Which of the following is NOT a treatment for angina?

Stent placement is not classified as a treatment specifically designed to alleviate angina. Angina typically results from inadequate blood flow to the heart muscle, and while stenting can improve blood flow, it is primarily a procedure intended for the treatment of coronary artery disease or to relieve blockages in the arteries.

The other options are more direct treatments or preventative measures for angina. Anticoagulants help prevent blood clots, thereby reducing the risk of myocardial infarction, which can lead to angina episodes. Nitroglycerin works by dilating blood vessels, which reduces the heart's workload and relieves angina pain by improving blood flow. Aspirin is used to inhibit platelet aggregation, preventing clot formation which can contribute to angina. Thus, stent placement serves a different role by addressing structural issues in the coronary arteries, rather than directly treating the symptoms of angina itself.