Dr (Prof). Tarun Kumar, Professor of Cardiology, DR RML Hospital
New Delhi. In our country, more than a million heart patients undergo angioplasty every year. But after six to nine months, 3 to 10 percent of patients are facing the stent’s restenosis problem. Now with the help of some new technologies, restenosis problems can be reduced.
What is Restenosis: Restenosis is a gradual re-narrowing of the stented segment that occurs mostly between 3 to 12 months after stent placement. In-stent-restenosis rate has come down drastically with ISR (In-stent-restenosis) rates of 30.1%, 14.6%, and 12.2% for BMS, first-generation DES, and second-generation DES, respectively. ISR still occurs in approximately 3 to 10% of patients within six to nine months.
We have learned that restenosis is a very complex process. With the advancement of technology, cardiac science is able to achieve a very low restenosis rate.
Imaging Technology-IVUS: Intravascular Ultrasound and OCT: optical Coherence Tomography
These Imaging technique helps in proper lesion characterization, vessel diameter assessment, and stent apposition which helps in optimization of PCI which in long term translate into a low rate of ISR. Intracoronary imaging has a growing role in guiding and optimizing PCI, especially as PCI in more complex and high-risk subsets. Imaging should be used prior to, during, and after stent deployment to obtain maximum benefit from the use of an imaging as it has an important role to play in all steps of a PCI procedure.
Polymer-free Stent: Currently in clinical usage are Polymer-free biolimus A9-eluting stents or with a biodegradable-polymer sirolimus-eluting stent or polymer-free sirolimus and probucol-eluting stents. In clinical trials, these polymer-free stents Showed noninferiority or numerically better outcomes than Stable polymer-based stents. Ten-year clinical outcomes of polymer-free versus durable polymer new-generation drug-eluting stent in patients with coronary artery disease with and without diabetes mellitus results of the Intracoronary Stenting and Angiographic Results.
Bioresorbable Stent: Bioresorbable scaffolds (BRS) represent the fourth evolution in myocardial revascularization therapies with extensive technological development and advancements. This stent is made of a metal that will automatically dissolve safely within the body two to three years after implantation and the patient’s artery returns to its normal position. The primary metals in this category are magnesium-based and iron-based alloys, although recently zinc has also been investigated
Rotablation and Intravascular Lithotripsy (Shockwave Therapy)
For Calcified lesion rotablation was in place for a long time but the recent addition of user-friendly IVL provided more arsenals to the armamentarium of the Intervention cardiologist.
Shockwave intravascular lithotripsy (IVL) is a novel device used in patients with calcified blockages. Shockwave Medical Coronary IVL Catheter is a single-use disposable catheter that is connected to an integrated balloon and fitted with multiple lithotripsy machines. This machine creates a sonic pressure wave for the affected area. This sonic pressure wave breaks down calcium, creating space in the artery. IVL popularity has been on the rise in view of a more user-friendly and short learning curve.
Proper usage of these technologies in properly selected patients can lead to a very low rate of In-stent restenosis (ISR) and very low future clinical events. Achievement of near Zero ISR is a dream of every cardiologist and a requirement for every patient and with further developments in cardiac technology, that day is not very far. Believe my words, the conglomerate of lifestyle changes with proper Optimization of PCI can do wonders.