A heart stent is a small, mesh-like tube used to treat blockages in the coronary arteries, the blood vessels that supply the heart muscle. Stent placement is a common medical intervention, often performed during percutaneous coronary intervention (PCI). While not a cure for heart disease, the stent mechanically restores proper blood flow. This device is permanently positioned within a narrowed artery to act as a scaffold, ensuring the vessel remains open and functional.
Understanding Coronary Artery Blockages
The need for a stent arises from Coronary Artery Disease (CAD), primarily caused by atherosclerosis. Atherosclerosis is a chronic, progressive inflammatory disease characterized by the buildup of plaque within the inner lining of the coronary arteries. This plaque is composed of fatty substances, cholesterol, cellular waste products, and calcium deposits. As plaque accumulates, the artery walls thicken and harden, causing the vessel to narrow, a process termed stenosis.
This narrowing significantly impairs the flow of oxygen-rich blood to the heart muscle, leading to reduced blood supply called myocardial ischemia. Lack of oxygen can cause symptoms like angina, often felt as chest pain or pressure. If the plaque ruptures, a blood clot (thrombus) can rapidly form, completely obstructing the blood vessel. This obstruction results in an acute myocardial infarction, commonly known as a heart attack. A stent mechanically addresses this flow-limiting blockage, whether it is stable or leading to an acute event.
How Stents Restore Blood Flow
The function of a coronary stent is to provide structural support to the artery wall after the blockage has been compressed and opened. It acts like a permanent scaffold, preventing the artery from collapsing or re-narrowing at the blockage site. The stent material is typically a metal alloy, such as stainless steel or cobalt-chromium, engineered to be flexible yet strong. Once expanded, the mesh structure pushes the accumulated plaque against the artery wall, immediately increasing the vessel’s inner diameter and restoring blood flow.
Stents are categorized into two types: Bare Metal Stents (BMS) and Drug-Eluting Stents (DES). BMS are simple metal mesh tubes, but they carry a risk of restenosis, the re-narrowing of the artery due to excessive scar tissue growth. DES represent the majority of stents used today and incorporate a polymer coating that slowly releases medication into the artery wall. This anti-proliferative drug inhibits the cellular overgrowth that causes scar tissue, substantially lowering the risk of restenosis compared to BMS. The choice between BMS and DES depends on the patient’s risk factors, artery size, and ability to tolerate long-term antiplatelet medication.
The Stent Placement Procedure
Stent placement is a minimally invasive procedure known as percutaneous coronary intervention (PCI), or angioplasty with stenting. The process begins with inserting a thin, flexible catheter into a peripheral artery, typically in the wrist (radial access) or the groin (femoral access). The cardiologist uses X-ray guidance (fluoroscopy) to navigate the catheter through the arterial network until it reaches the blocked coronary artery.
Once at the blockage, a specialized catheter with a deflated balloon is threaded over a guide wire and positioned across the narrowed segment. The balloon is inflated, forcing the hardened plaque outward and compressing it against the artery wall, widening the vessel. The deflated balloon then delivers the collapsed stent to the blockage location. Inflating the balloon a second time expands the stent, embedding its metal mesh into the artery wall and locking the vessel open. The balloon and catheter are removed, leaving the stent permanently in place to ensure continuous blood flow.
Post-Procedure Recovery and Medication
Recovery following stent placement is typically rapid due to the minimally invasive nature of the procedure, often requiring only a short hospital stay. Immediate recovery focuses on managing the catheter insertion site to prevent bleeding and ensuring patient stability. The most important element of post-procedure care involves a specific medication regimen to maintain the stent’s patency.
All patients are prescribed dual antiplatelet therapy (DAPT), a combination of two medications designed to prevent blood clots from forming on the stent’s surface. This therapy includes aspirin and a P2Y12 inhibitor, such as clopidogrel, which reduce the “stickiness” of platelets. Adherence to DAPT is paramount for a specific duration, ranging from several months to a year or longer, depending on the stent type and the patient’s risk profile. Long-term cardiac health also requires significant lifestyle adjustments, including a heart-healthy diet, regular physical activity, and managing risk factors like high blood pressure and cholesterol.