Addressing their colleagues at the American College of Cardiology's annual scientific session in Chicago, Cedars-Sinai researchers will present information on topics that range from discoveries in cellular and basic immune mechanisms that impact development of atherosclerosis to the evolution of next-generation stents that show promise in keeping treated arteries open.
P.K. Shah, M.D., director of Cedars-Sinai's Division of Cardiology and the Atherosclerosis Research Center, will moderate or co-chair several sessions:
"Acute Coronary Syndromes," Sunday, Mar. 30, from 11 a.m. to 12:30 p.m. at McCormick Place, Room S402; "Vulnerable Plaque and Pathophysiologic Features of Acute Coronary Syndrome," Monday, Mar. 31, 11 a.m. to 12:15 p.m. at McCormick Place, Vista S406A; "Metabolic Syndrome: Everything We Wanted to Know But … ," Tuesday, April 1, 8:30 a.m. to noon; and "Using Risk Stratification Tools for Treatment Decisions in Patients with Acute Coronary Syndromes," Tuesday, April 1, noon to 3:30 p.m., McCormick Place, Vista S406A.
Dr. Shah, who will be honored as a gifted teacher in an ACC ceremony, holds the Shapell and Webb Family Endowed Chair in Cardiology at Cedars-Sinai. Embargoed until April 1, at 6:30 p.m.
C. Noel Bairey Merz, M.D., the primary investigator of a federally funded, four-center study on heart disease in women (Women's Ischemia Syndrome Evaluation or WISE), will co-chair "Hormone Replacement Therapy and the Heart: What We Knew, What We Know," Monday, Mar. 31, from 4 to 5 p.m.
Dr. Bairey Merz is also involved in a number of sessions that will highlight recent WISE-related studies. (IRB # 2398: The NHLBI-sponsored Women's Ischemia Syndrome Evaluation). For example, during a poster session from 9 to 11 a.m. Sunday, Mar. 30, researchers will present details of research that links reduced kidney function with coronary artery disease in women. The presentation is titled "Mildly Reduced Creatinine Clearance is Associated With Coronary Artery Disease in Women: The NHLBI-Sponsored WISE Study."
Using lab tests that measure levels of creatinine and other blood chemistry, the researchers found that the prevalence of significant angiographic coronary artery disease was greater in women with mild renal insufficiency than in those with normal kidney function. Those with mild renal insufficiency were more likely to have significant disease affecting multiple coronary arteries, a greater degree of artery blockage, and more "severe" scores based on angiography.
The study's results are the first to demonstrate that mild renal insufficiency is an independent predictor for significant coronary artery disease in women with chest pain. The authors point out that it is unlikely that creatinine itself leads to the development of atherosclerosis but instead may be a marker for other factors that promote the disease. If these results are supported in additional studies, a routine blood test available in a physician's office may become one tool to help predict which women are at increased risk for developing coronary artery disease.
Dr. Bairey Merz, who holds Cedars-Sinai's Women's Guild Chair in Women's Health, directs the Women's Health Program and the medical center's Preventive and Rehabilitative Cardiac Center.
Among the technological advances to be discussed is a new-generation stent that in laboratory tests and an animal study appears to overcome several design limitations of existing models.
Balloon angioplasty is often used to open coronary arteries blocked by plaque deposits. A metal device called a stent may be positioned at the site of the blockage and expanded to keep the artery from re-closing. Stents often contain drugs that assist in preventing restenosis.
Commonly used stents, however, typically change shape when they are expanded, which affects the rate at which medication is released. Too little drug reduces effectiveness; too much drug at a particular site can be toxic and damage the artery.
The new stent is designed with honeycombed struts that have "hinges" at the ends. The hinges absorb the stress of expansion while all other elements of the stent retain their proper shape. The numerous holes can be filled with polymer and/or polymer/drug combinations.
Early results indicate that this structure may give physicians far greater control in the manner in which medication is released over time and space within the artery. For example, by filling certain holes with one drug, inserting a physical barrier, and placing a different drug in holes on the other side, physicians may be able to tailor drug delivery to the immediate artery wall while providing a different medication over a larger area.
By choosing from a variety of barriers that degrade at differing rates, the amount of drug released can be programmed to increase or decrease over time. In other words, the structure of the device, not just the chemical properties and interactions of the drugs, play a role in determining the location and rate at which medication is released.
Laboratory tests show the device to be structurally sound, and in an animal study it was well tolerated and reliable. Dr. Neal Eigler and Dr. Frank Litvack directed this contract research of a proprietary next generation stent drug delivery system.
Details on the study, "Stent-Based Programmable Erodable Polymer Drug Release Systems Are Nontoxic in Porcine Arteries," will be available at the "Novel Stent Designs and Coatings" poster session taking place from 9 to 11 a.m. Tuesday, April 1, in McCormick Place Hall A.
During a poster session on Monday, Mar. 31, from 9 to 11 a.m., research scientist Hrayr S. Karagueuzian, Ph.D., will present an abstract on "Radioactive Cigarettes and Corporate Strategy in Light of Evidence Derived From Declassified Tobacco Industry Documents."
Looking into the influence of nicotine exposure on heart rhythm, Dr. Karagueuzian and his associates have begun to collect and analyze data dating to the early 1960s – much of which was classified until recently – showing that the tobacco industry knew that tobacco smoke contained radioactivity.
According to published academic articles, elevated radioactive materials that make their way into tobacco leaves readily pass through filters and also exist in smoke that reaches the lungs of smokers and non-smokers. "It is this redioactivity that may well cause lung cancer in smokers," asserted the former Surgeon General in 1990 on national television.
Tobacco company documents indicate that industry scientists and officials were conducting research on radioactivity even as far back as the 1950s, and knew about the potential that radioactivity in cigarette smoke to cause lungs cancer. However, over the years, the industry suppressed results of its findings to avoid alerting the public to the possible cancer risk posed by radioactivity in tobacco smoke. Furthermore, while the industry knew of ways to remove radioactivity from tobacco, these methods were deemed unacceptable lest they spoil prompt nicotine delivery to the brains of smokers, according to the Cedars-Sinai researchers' preliminary search.
Dr. Bairey Merz will co-chair a special session on Tuesday, April 1 from 4 to 5 p.m. "The 34th Annual Bethesda Conference Report: Can Atherosclerosis Imaging Techniques Improve the Detection of Patients at Risk for Ischemic Heart Disease?" will be at McCormick Place, Room S405.
Dr. Shah will participate in a special "Meeting Highlights" session on Wednesday, April 2 from 10:30 a.m. to 12:30 p.m. as the annual convention draws to a close. "Myocardial Ischemia and Infarction" will be at McCormick Place, Lecture Hall D.