Dissolvable Heart Stents Richard Melpignano

Coronary Heart Disease Coronary Heart Disease (CHD) is, as of 2012, the leading cause of death worldwide. Plaque in blood accumulates against the walls of the Coronary Artery, which returns oxygen rich blood from lungs to heart If left untreated, will lead to blood clots/heart attacks

Traditional Treatments Coronary Artery Bypass Surgery (High Risk) Cholesterol Lowering Medication, Nitroglycerin, Beta- Blockers etc. (Less Effective) Angioplasty

Minimally invasive Involves the insertion of a mesh stent which expands to fit the coronary artery, forcing plaque against the artery wall, allowing significantly increased blow flow to the heart Stents have traditionally been made of various metals, and may or may not be drug eluting

Problems Effective, but often delay natural healing process of the arteries If metal mesh is not inserted properly, plaque may actually build up on the stent, called stent thrombosis (kills 1 in 200 patients in procedure) To improve upon these conditions, Abbott Laboratories in IL have been working on a biodegradable polymer drug eluding stent

Polymer (DES) Stent Made of biodegradable material called polylactide Inserted into Coronary Artery through similar method as metal stents Designed to completely dissolve into the bloodstream within 2-3 years after procedure

Procedure A dye that can be seen on X-rays is released into the blood in order to pinpoint the location and severity of the blockage Catheter is inserted into the patients body, usually into the groin, but may be inserted into the arm or thigh as well Catheter is lead along the artery until it reaches the blockage, where the mesh is forced against the artery wall through the inflation of a balloon, compressing the plaque blockage The balloon is deflated and the catheter is removed from the body

Results In comparing metal stents with metal DES stents, the DES stents have shown more instances of heart complications than ones without supporting drugs But, biodegradable DES stents were found to be safer than both of the metal stents The risk of stent thrombosis, lesion revascularization, and myocardial infarction were significantly reduced

ABSORB III Clinical Trials Early in September, these trials enrolled 2,250 patients across the country to test the effectiveness of dissolvable heart stents Some facilities participating include Mount Sinai Medical Center and the Stony Brook University Heart Institute

Future Many physicians believe that these dissolvable heart stents will someday replace metal stents (which have been used in over 6 million procedures) It was approved for testing in Europe in 2011 and has been successful in trials If trials are successful, it is expected to be available in the United States by 2015 The cost is estimated to be between $1500-$2000

Work Cited [1] Cutlip, Donald, MD, and J. Dawn Abbott, FACC. "Coronary Artery Stent Thrombosis: Incidence and Risk Factors." Coronary Artery Stent Thrombosis: Incidence and Risk Factors. Up To Date, 13 May Web. 26 Sept [2] "European Heart Journal." Biodegradable Polymer Drug-eluting Stents Reduce the Risk of Stent Thrombosis at 4 Years in Patients Undergoing Percutaneous Coronary Intervention: A Pooled Analysis of Individual Patient Data from the ISAR-TEST 3, ISAR-TEST 4, and LEADERS Randomized Trials. N.p., 21 Jan Web. 26 Sept [3] "How Are Stents Used?" - NHLBI, NIH. National Heart, Lung, and Blood Institute, n.d. Web. 26 Sept [4] Jaspen, Bruce. "Abbott's Dissolvable Heart Stent Gets OK for Use in Europe." Chicago Tribune. N.p., 10 Jan Web. 26 Sept [5] Lu ̈ scher, Thomas, MD, Jan Steffel, MD, Franz R. Eberli, MD, Michael Joner, MD, Gaku Nakazawa, MD, Felix C. Tanner, MD, and Renu Virmani, MD. "Drug-Eluting Stent and Coronary Thrombosis." Biological Mechanisms and Clinical Implications (2007): n. pag. American Heart Association- Circulation. Web. 26 Sept [6] "Stony Brook Heart Institute Evaluates First Dissolvable Stent." Stony Brook Heart Institute Evaluates First Dissolvable Stent. Stony Brook University, 20 Sept Web. 26 Sept [7] Woods, Lauren. "Fully Dissolvable, Temporary Stent for Opening Heart Artery Blockages." Fully Dissolvable, Temporary Stent for Opening Heart Artery Blockages. The Mount Sinai Hospital, 17 Sept Web. 26 Sept