A heart stent is a small, mesh tube designed to keep arteries open and improve blood flow, particularly in the coronary arteries. These devices are typically placed during a procedure called angioplasty, acting as a scaffold to support the artery after blockages, often caused by plaque buildup, are cleared. While stents are generally intended to be permanent implants, their continued effectiveness over time is not a fixed duration. A stent’s long-term function is influenced by its type, the patient’s health, and their lifestyle choices.
Stent Types and Expected Lifespan
Two primary types of heart stents are commonly used: bare-metal stents (BMS) and drug-eluting stents (DES). Bare-metal stents are simple metal mesh tubes that prop open the artery. However, the body’s natural healing response can lead to an overgrowth of tissue within the stent, causing the artery to narrow again, a process known as restenosis. The risk of restenosis with BMS ranges from 16% to 44%.
Drug-eluting stents, which are more frequently used today, are bare-metal stents coated with medication slowly released into the artery. This medication helps prevent the excessive tissue growth that can lead to re-narrowing. DES have significantly reduced restenosis risk compared to BMS, with rates typically falling between 5% and 10%. Both BMS and DES are designed to remain permanently in the artery, with the artery’s inner lining growing over the stent surface to integrate it into the vessel wall.
Factors Affecting Stent Durability
Several factors influence a stent’s long-term durability. Patient-specific health conditions play a significant role. Individuals with chronic diseases like diabetes, chronic kidney disease, or uncontrolled high blood pressure may face an increased risk of complications such as restenosis or stent thrombosis. Inflammation within the arterial wall and an individual’s biological response to the stent can also contribute to issues.
Lifestyle choices directly affect stent longevity. Smoking is a known risk factor for both restenosis and stent thrombosis. A diet high in unhealthy fats and a lack of physical activity can contribute to plaque buildup, affecting not only the stented artery but also other vessels. The characteristics of the original arterial blockage also matter. Complex lesions, such as those that are long, heavily calcified, involve bifurcations (where an artery splits), or require multiple overlapping stents, can present greater challenges and may be associated with increased risks of complications.
Addressing Stent Complications
Even with successful implantation, stents can develop complications, primarily in-stent restenosis and stent thrombosis. In-stent restenosis occurs when the artery re-narrows within the stent due to scar tissue formation. Symptoms often mimic those experienced before the stent placement, such as chest pain or shortness of breath. While not immediately life-threatening, it indicates reduced blood flow.
Stent thrombosis is a serious complication, involving a blood clot inside the stent. This can lead to a sudden and severe blockage, often resulting in a heart attack or cardiac death. Symptoms can include sudden chest pain, shortness of breath, nausea, or sweating. If a stent complication arises, treatment options vary depending on the specific issue and its severity. These may include additional angioplasty with or without re-stenting (often utilizing a drug-eluting stent for restenosis), or in more complex cases, coronary artery bypass graft surgery. Vascular brachytherapy, which involves localized radiation, can also inhibit tissue growth in cases of restenosis.
Supporting Long-Term Stent Function
Maintaining a heart stent’s long-term effectiveness depends on consistent patient commitment to medical and lifestyle recommendations. Adherence to prescribed medications is important, especially dual antiplatelet therapy (DAPT), which typically includes aspirin and another antiplatelet drug. This therapy helps prevent blood clots from forming within the stent and the overall cardiovascular system. Prematurely stopping antiplatelet medication significantly increases the risk of stent thrombosis.
Regular follow-up appointments with a cardiologist are important to monitor stent function and overall heart health. Adopting a heart-healthy lifestyle, including a balanced diet, regular physical activity, and smoking cessation, contributes significantly to preventing further plaque buildup and supporting arterial health. Managing underlying conditions such as high blood pressure, high cholesterol, and diabetes is also important, as these can negatively impact stent durability and increase the risk of future cardiac events.