A 72-year-old woman develops recurrent angina symptoms after stent placement. What is the most likely cause of her symptoms?

• A. Aneurysm of the right coronary artery
• B. Dissection of the right coronary artery
• C. Neointima formation in the right coronary stent
• D. Thrombosis of the right coronary artery

Answer: (C)

Recurrent angina symptoms after stent placement are often associated with the process of neointimal hyperplasia, which refers to the thickening of the vessel wall due to the proliferation of smooth muscle cells. This process is a common response to vascular injury caused by the stenting procedure. In response to the placement of the stent, the body attempts to heal the damaged area, leading to the formation of new tissue within the stent itself, which can narrow the vessel lumen over time and contribute to angina.

Neointimal hyperplasia is particularly relevant in cases where bare-metal stents are used, as these have a higher propensity for such tissue growth compared to drug-eluting stents that release medication to inhibit this process. The result is that despite the initial successful placement of the stent, patients can experience recurrent symptoms due to this narrowing.

In contrast, other options like aneurysm or dissection may cause symptoms, but they are less common complications following stent placement compared to neointimal hyperplasia. Thrombosis can occur and lead to acute coronary syndromes, but it typically presents more urgently rather than as recurrent angina over time. Thus, the most likely reason for recurrent angina symptoms in this context is indeed the formation of