Use of Drug-Eluting Stents during Percutaneous Coronary Intervention

Narrowing of arteries and obstruction in the blood supply to the heart may lead to major cardiovascular events such as ischemia, myocardial infarction (heart attack), stroke and more. Plaques that build-up in the coronary arteries can behave in different ways: a plaque that grows to certain size and stops, a plaque that eventually causes blockage or a plaque that suddenly ruptures causing a complete block of blood supply. Chest pain during exertion is a sign of stable plaque whereas  heart attack or stroke occurs when there is a plaque rupture. Cardiologists will either opt for drug therapy or revascularization procedures - percutaneous coronary intervention and Coronary Artery bypass Grafting - depending on the diagnostic results of CAD patients.

Physicians often prefer a less invasive approach as it cuts down the complications and speeds up the recovery time. Percutaneous coronary intervention (PCI), also known as coronary angioplasty have become one of the most preferred coronary interventions because of its improved outcomes and dramatic reduction of major adverse cardiac events (MACE). The procedure mainly involves widening of the narrowed artery with an inflated balloon-tipped catheter thereby restoring the normal blood flow. However, in some cases it may be essential to perform a stenting procedure to keep the arteries open. An interventional cardiologist has to take the decision about whether or not to place the stents, based on angiographic data and fractional flow reserve measurements. Coronary Fractional Flow Reserve technique used during catheterization provides a lesion-specific index that guides the physician to decide the treatment approach. Stents are placed only when the measured FFR value is less than 0.75, otherwise the patient is prescribed with medical therapy.

The well-validated and threshold value provided by the coronary fractional flow reserve technique have become a standard and reliable way to demonstrate or exclude ischemia-inducing lesions. To return to the subject of stenting, two classes of stents namely Bare-metal stents (BMS) and Drug-Eluting Stents (DES) are available for PCI. DES has superseded the use of BMS as it prevents the formation of scar tissue thereby reducing the likelihood of restenosis to a greater extent. For instance, Cre8™ DES (a polymer-free DES coated with Amphilimus™) is a new step in DES technology that overcomes the polymer-associated complications and minimises the risk of thrombosis. The amphicilic carrier present in Cre8™ DES proposes a controlled and directed drug elution. Dramatic development of nanotechnology and DES technology offers a promising approach in developing a biocompatible stent that would completely eliminate restenosis and thrombosis in near future.