Stent is a tiny metallic mesh tube implanted during PCI into a diseased coronary artery to expand it and keep it open.
Stent insertion or stenting is a part of PCI (coronary angioplasty), an invasive catheter-based procedure for treating angina and coronary artery disease. Previously used bare-metal stents (BMS) are now largely superseded by drug-eluting stents (DES), which are coated with special medication to avoid restenosis, recurrence of narrowing of the coronary artery. Restenosis is a part of the exaggerated healing process with overgrowth of the lining of the coronary artery causing a reduction in diameter of the artery, impairment of the blood flow and thus recurrence of angina. Restenosis appeared in patients treated with BMS in up to 30%, whereas in DES, the restenosis rate is about 10%. The drugs used in DES have immunosuppressive effects but are safe without systemic side effects because of the local delivery inside the coronary artery. Most drug eluting stents use paclitaxel or ‘limus’ drugs such as sirolimus, everolimus and zotarolimus.
Stents, particularly drug-eluting stents, require the use of a combination of two blood-thinning drugs, which prevent blood clotting due to aggregation of platelets (therefore antiplatelet medication). This dual antiplatelet medication (DAP) consists typically of Aspirin 75mg daily for life and one other drug (Clopidogrel 75mg daily, Ticagrelor 90mg twice daily or Prasugrel 10mg daily), which is usually taken for 12 months. DAP reduces the risk of blood clots within the stent, leading to sudden obstruction of the coronary artery and massive heart attack. The use of these drugs is absolutely mandatory for the period prescribed by your cardiologist.