1. On Pump Coronary Artery Bypass Grafting (CABG) v. Off Pump CABG David Kim Independent Research GT

2. About Me My name is David Kim and I am currently a junior at Oakland Mills High School. I am a track runner, a tennis player, a member of the Alpha Achievers, Math Team, National Honor Society, MESA, and the Scroll. Currently, I am researching the effects of different heart surgeries and to provide a solution which I will talk later in this presentation. So why the heart? Why is researching this appropriate? I want to become a professional heart surgeon. I want to research more about cardiac surgery. If you ask me, I enjoy what I am doing in my class. More than 500,000 people undergo CABG in the US each year. Furthermore, blocked arteries caused by plaque buildup/blood clots are the leading cause of death in the US. This is a viable and workable study that I can research.

3. Abstract My main area of interest is cardiothoracic surgery, or the surgery of the heart, the greater vessels, and the organs near the heart. I am researching the effects of on pump cardiac surgery and off pump cardiac surgery to see if one or the other is more effective. I want to support my research with data and statistics provided from my sources. Potentially, this will lead me to design a more efficient type of surgical procedure and present it to my authentic audience. I plan to present my research in small conferences to the PTA and other events.

4. My Advisor Michael K. Woods is my advisor, a retired cardiothoracic surgeon who live in California. Mrs. Creed helped me get in touch with Dr. Woods. Conversations have been made on email/phone. He traveled many places like West Africa. Advisor’s Contact: michaelkwood@yahoo.commichaelkwood@yahoo.com

5. Coronary Artery Bypass Surgery (CABG) Coronary artery bypass graft surgery (CABG) is a procedure used to treat coronary artery disease. Coronary artery disease is narrowing of the coronary arteries (the blood vessels that supply oxygen and nutrients to the heart muscle), caused by a buildup of fatty material within the walls of the arteries. This buildup causes the inside of the arteries to become narrowed, limiting the supply of oxygen-rich blood to the heart muscle.

6. Methods A patient needs a CABG operation because they need improved blood flow to the heart muscle that cannot be improved with medical therapy or angioplasty with stents. There are 2 different methods of doing CABG: the traditional way, which is called “on-pump CABG,” and the newer way, which is called “off-pump CABG.” On-pump CABG requires the heart-lung machine while off-pump does not. Opinion is still divided on which has a lower mortality rate and which is most efficient.

7. First Option: Angioplasty with Stent

8. Cholesterol plaques cause heart disease. A cholesterol plaque can suddenly rupture. The sudden blood clot that forms over the rupture then causes a heart attack or stroke. Reducing cholesterol and other risk factors can help prevent cholesterol plaques from forming.

10. Second Option: Bypass and Surgery

11. If not by angioplasty, to treat the blocked arteries is to bypass the blocked portion of the coronary artery with another piece of blood vessel. Blood vessels, grafts, used for the bypass procedure are pieces of a vein taken from the legs, chest, or wrist. One end of the graft is attached above the blockage and the other end is attached below the blockage. The blood is rerouted around; blood is able to reach the heart muscle. This bypass of the blocked coronary artery is done by performing coronary artery bypass surgery.

12. CABG Traditionally, in order to bypass the blocked coronary artery in this manner, the chest is opened in the operating room and the heart is stopped for a time so that the surgeon can perform the bypass. In order to open the chest, the breastbone (sternum) is cut in half and spread apart. Once the heart is exposed, tubes are inserted into the heart so that the blood can be pumped through the body during the surgery by a cardiopulmonary bypass machine (heart-lung machine). The bypass machine is necessary to pump blood while the heart is stopped and kept still in order for the surgeon to perform the bypass operation.

13. Off-pump CABG Surgery Off-pump CABG is: widely performed safe effective and there are numerous techniques available patients with aortic disease precluding bypass

14. Cont. ADVANTAGES avoids bypass less bleeding, less transfusion no K+ load, fluid load, coronary air embolism (basically no particle buildup) no risk of bypass machine failure less cost less equipment less staff DISADVANTAGES However needs skilled staff not all coronary arteries well reached by technique more graft failure and risk of bleeding neuropsychological benefit not shown in trial more difficult with disease or small artery disease

15. On-pump CABG Surgery On-pump CABG is: performed while the heart is stopped blood supply must be provided to the rest of the body when the heart is stopped surgeons use the cardiopulmonary bypass machine (also known as the heart-lung machine or the pump) pipes are placed in the heart to drain impure blood to the pump, where it is purified and pumped back into the patient Keep it stopped but also nourish it when it is still. The bypass grafts are then constructed. At the end of the procedure, the heart is restarted.

16. Cont. Advantages On-pump CABG today is a safe procedure that has a small risk of death and/or complications. The average risk of this procedure to a low-risk patient is 1-2%. Development of new technology has made the heart-lung machine very safe. Disadvantages The patient’s other health-threatening conditions increase these risks. Some of the important complications that can occur with this technique are stroke, kidney or liver failure, decrease in higher mental function, and bleeding.

17. Research If the number of needed coronary artery bypass grafts are lower (1 or 2) and the co-morbidities are higher (such as renal disease with elevated Cr, pulmonary insufficiency, older age, etc.), and if a program has a good experience with “off-pump” CABG, then patients with tend to do better with the off-pump approach. However, if the needed grafts are higher, the targeted vessels smaller (but still need bypass) then on-pump will lead to better results.

18. Cont. The patient may only need one or two grafts to one or two vessels that are severely narrowed and be life threatening such as a left main stenosis. Off-pump may be better in selected cases, but on-pump is tried and true with many more years of proven results with decades of follow up. According to “A systematic review of randomized trials comparing revascularization rate and graft patency of off- pump and conventional coronary surgery,” in a meta-analysis of randomized trials, patients undergoing off-pump coronary surgery had a lower rate of revascularization and lower graft patency (or unblock) than did patients undergoing conventional coronary surgery.

19. On and Off Pump Rate of Encephalopathy, Dialysis, Sternal Wound Infection, Need for Red Blood Cell Transfusions/On and Off Pump Rates of Death, Stroke, Heart Attack during Surgery Graph 1: Off-pump surgery had a significantly lower rate of encephalopathy, dialysis, sternal wound infection (SWI) & need for red blood cell transfusions (PRBC). Graph 2: Both on-pump and off-pump surgery had low rates of death, stroke, or heart attack (MI) during surgery.

20. Mortality Rates of ESRD and non-ESRD Patients in the US Graph depicting the constantly decreasing trend in mortality of patients with end-stage renal disease (ESRD) undergoing coronary artery bypass grafting (CABG) compared to patients without ESRD, over a 15-year period. Data from Parikh DS, Swaminathan M, Archer

21. Conclusion Both on-pump and off-pump surgery had low rates of death, stroke, or heart attack during surgery. However, off-pump surgery specifically had a significantly lower rate of encephalopathy, dialysis, sternal wound infection (SWI) & need for red blood cell transfusions (PRBC). Cost always come into account. Off-pump CABG costs less than on-pump: $11,744 versus $13,720. (according to The Canadian Journal of Cardiology) The difficulty with smaller and more numerous arteries that need to be bypassed however should be reserved for on-pump.

22. Cont. By the end of my research, I will take into account the effects of both CABG surgeries on women, men, people of different age, and other factors.

23. Picture URL Links http://www.123rf.com/photo_15915115_illustration-of-a-human-heart-cross- section.html http://www.123rf.com/photo_15915115_illustration-of-a-human-heart-cross- section.html http://my.clevelandclinic.org/heart/disorders/cad/offpump.aspx http://www.webmd.com/heart-disease/heart-failure/aortic-valve-replacement- final http://www.webmd.com/heart-disease/heart-failure/aortic-valve-replacement- final http://www.intechopen.com/books/artery-bypass/impact-of-renal-dysfunction- and-peripheral-arterial-disease-on-post-operative-outcomes-after-coronar http://www.intechopen.com/books/artery-bypass/impact-of-renal-dysfunction- and-peripheral-arterial-disease-on-post-operative-outcomes-after-coronar http://www.gograph.com/illustration/businessman-making-a-presentation- gg62534950.html http://www.gograph.com/illustration/businessman-making-a-presentation- gg62534950.html http://www.bostonscientific.com/lifebeat-online/cardiac-procedures/angioplasty- and-stents.html http://www.bostonscientific.com/lifebeat-online/cardiac-procedures/angioplasty- and-stents.html http://en.wikipedia.org/wiki/Coronary_stent http://drsvenkatesan.wordpress.com/2008/11/06/why-is-lima-graft-superior-than- saphenous-venous-graft/ http://drsvenkatesan.wordpress.com/2008/11/06/why-is-lima-graft-superior-than- saphenous-venous-graft/