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News from the American Heart Association Scientific Sessions 2005:Held November 13-16, in Dallas, Texas

Major Advances in Techniques, Devices, Medications Spur Update of PCI Guidelines Multidisciplinary document benefits from broad view of generalists, detailed focus of interventionalists Updated guidelines on percutaneous coronary intervention (PCI) were jointly released by the American College of Cardiology, American Heart Association, and Society for Cardiovascular Angiography and Interventions. The science shows that patients truly benefit from a ‘door-to-balloon time’ of 90 minutes or less. We have consistently looked at where the science says we should be, and challenged ourselves, said Sidney C. Smith, Jr, MD, FAHA, FACC, of one of the goals of the document. Dr. Smith headed the guideline writing committee and is a professor of medicine and director of the Center for Cardiovascular Science and Medicine at the University of North Carolina at Chapel Hill. The PCI Guidelines were last revised in 2001. In four short years, there have been dramatic advances in PCI techniques, devices, and medications. Drug-eluting stents are among the most notable. The use of drug-eluting stents is rapidly changing the treatment of coronary artery disease, said Ted Feldman, MD, FSCAI, FACC, professor of medicine at Northwestern University Medical School in Chicago and director of the cardiac catheterization laboratory at Evanston Hospital, Evanston, IL. These guidelines address the real-world issues that are important to the use of drug-eluting stents. Key Findings of the ACC/AHA/SCAI 2005 Guideline Update on Percutaneous Coronary Interventions Recommended Annual Operator Volume For patients undergoing primary PCI for heart attack, the guideline recommends that PCI procedures should be performed by experienced physicians who perform more than 75 elective PCI procedures per year and at least 11 PCI procedures on heart attack patients. As in the 2001 guideline, the 2005 update continues to recommend that elective PCI procedures should be performed by physicians who perform at least 75 PCI procedures annually at high-volume centers. The guideline goes on to emphasize the importance of data collection and analysis, noting that elective PCI should be performed by operators and institutions whose historical and current risk-adjusted outcomes statistics are in line with those in national data registries. Anatomic Indicators Citing recent PCI clinical trials, the authoring organizations note that it is reasonable to perform PCI on patients who have significant coronary artery disease of the left main coronary artery but who are not eligible for bypass surgery. Careful post-procedure surveillance for these patients is indicated. It is reasonable to perform a post-PCI angiogram in 2 to 6 months as part of their follow-up. Onsite Surgical Facilities for Elective Angioplasty As in the 2001 guideline, it is recommended that elective PCI should not be performed at institutions that do not have onsite cardiac surgery facilities. Drug-eluting Stents (DES) Referencing recent clinical trials (e.g., RAVEL, SIRIUS, TAXUS I, TAXUS IV), the 2005 PCI Guideline recommends that physicians consider using DES over bare metal stents in many settings, including in diabetic patients, those with longer lesions (mean: 14.4 mm), and with smaller-diameter vessels (mean: 2.8 mm). The document notes that, although DES show promise, long-term follow-up is needed. Use of Distal-Protection Devices According to the 2005 guideline update, distal embolic protection devices should be used whenever it is technically feasible in patients who are undergoing PCI to saphenous vein grafts the veins in the legs that are transplanted to the heart during bypass surgery. These devices require further study and, to date, have not been shown to benefit heart attack patients undergoing primary PCI. Post-Procedural Recommendations The 2005 PCI Guidelines Update includes extensive recommendations regarding monitoring and managing patients who have undergone PCI procedures. In addition to risk-factor modification, all post-PCI patients should begin taking a regimen of aspirin and clopidogrel unless these medicines are contraindicated. ACE inhibitors should be considered for all patients with coronary heart disease, left ventricular dysfunction, or high blood pressure. All patients who have suffered a heart attack or have another acute condition, such as left ventricular dysfunction, should be given beta-blockers for at least six months, unless there are contraindications. Diabetic patients need glucose-lowering therapies that will bring their HbA1c levels to less than 7 percent. Aggressive lipid lowering therapy (LDL-C SonoSite Initiates Multi-Center Cardiovascular Research Study Ultrasound Study to Assess Carotid Intima Media Thickness in an Office Setting SonoSite, Inc. announced at the 2005 American Heart Association (AHA) Scientific Sessions that it is initiating a multi-center study to determine whether the addition of an ultrasound examination evaluating carotid artery wall thickness (CIMT), performed in the office setting, will provide a more effective tool for risk assessment and prevention of cardiovascular disease than current clinical methods alone. Over 20 years of clinical research has shown that the thickness (T) of the two innermost layers of the carotid artery wall, the intima (I) and media (M), begins to increase before plaque is evident within the vessel. This increased wall thickness is associated with an increased risk of cardiovascular disease. IMT addresses the need to identify those patients who are asymptomatic or have limited risk factors, such as moderately elevated cholesterol levels, who may be at greater than apparent risk for a cardiovascular event,- explains James H. Stein, MD, Associate Professor, University of Wisconsin Medical School. Dr. Stein is the Director of the University of Wisconsin Atherosclerosis Imaging Research Program and principal investigator of the study. "Although IMT is recognized as a valuable adjunct in cardiovascular risk stratification, it primarily has been used as a research tool," Dr. Stein stated. "With the advent of high-resolution, hand-carried ultrasound systems and software algorithms, it is more practical to incorporate this tool into clinical practice. Through this trial, we hope to determine if health care professionals can accurately perform this exam in the office setting and thereby detect cardiovascular disease before it causes a heart attack or stroke." Until recently, measuring cholesterol or C-Reactive Protein (CRP) have been among the few options in evaluating the risk of cardiovascular disease. However, clinical studies suggest that IMT may be more predictive and specific to cardiovascular risk than either CRP or traditional lipid profile alone, making IMT an important tool for identifying patients at increased risk for cardiovascular disease. Called "OPACA" for Office Practice Assessment of Carotid Atherosclerosis using Handheld Ultrasound Study, investigators plan to enroll 525 patients at medical centers located in Philadelphia; Minneapolis; New York City; Chicago; Boise, Idaho; and Rochester, Minnesota. Data collection and analysis is expected to be completed by June of 2006. The study will use SonoSite's MicroMaxx system with embedded SonoCalc software, ahand-carried ultrasound system weighing just under eight pounds, and a L38 linear array transducer. The noninvasive ultrasound examination can be completed in approximately 15 minutes and does not expose a patient to ionizing radiation. Introduced a year ago at the 2004 AHA Scientific Sessions, SonoSite's patented SonoCalc IMT automated edge detection technology provides physicians with the ability to analyze the IMT of a patient's carotid artery. IMT has been used as an indicator of efficacy in the development of several statin and antihypertensive drugs and is widely recognized as a surrogate marker for identifying and evaluating the vascular disease and its progression, both indicators of heart disease and stroke. Aggressive Lowering of LDL-Cholesterol Level Shows Limited Benefit for Patients With Previous Heart Attack Patients who have had a heart attack and are treated with a high dose of a statin drug did not have significant reduction in the primary outcome of major cardiac events (coronary death, nonfatal acute heart attack, or cardiac arrest with resuscitation), but did appear to have reduced risk when certain secondary outcomes (composite end points of any coronary heart disease event) were examined, according to a study presented at the American Heart Association's annual meeting. Terje R. Pedersen, MD, PhD, of Ulleval University Hospital, Oslo, Norway and colleagues with the Incremental Decrease in End Points Through Aggressive Lipid Lowering (IDEAL) study examined whether intensive lowering of LDL-C with atorvastatin at the highest recommended dose would be more beneficial compared with the moderate, most widely used dose of simvastatin. The randomized trial was conducted at 190 cardiology care and specialist practice centers in northern Europe between March 1999 and March 2005, with a median (mid-point) follow-up of 4.8 years. The study included 8,888 patients aged 80 years or younger with a history of acute myocardial infarction (MI). Patients were randomly assigned to receive a high dose of atorvastatin (80 mg/d (n=4,439), or usual-dose simvastatin (20 mg/d; n=4,449). During treatment, mean LDL-C levels were 104 mg/dL in the simvastatin group and 81 mg/dL in the atorvastatin group. The primary end point of coronary death, acute myocardial infarction, or cardiac arrest with resuscitation occurred in 463 patients (10.4 percent) in the simvastatin group and in 411 (9.3 percent) in the atorvastatin group and was not statistically significantly different between the two groups. There were 178 coronary deaths (4.0 percent) in the simvastatin group vs. 175 (3.9 percent) in the atorvastatin group. Nonfatal myocardial infarction occurred in 321 patients (7.2 percent) in the simvastatin group and in 267 (6.0 percent) in the atorvastatin group. The composite secondary end point of a major cardiovascular event including stroke was reduced in the atorvastatin group. Similarly, there were reductions in the risk of nonfatal MI, any CHD event, and any cardiovascular event. The risk of death from any cause was similar in both study groups. There were no significant differences in noncardiovascular deaths between the treatment groups. There were no significant differences in the frequency of serious adverse clinical events between the 2 groups. Patients in the atorvastatin group had higher rates of drug discontinuation due to nonserious adverse events. "In summary, when comparing standard and intensive LDL-C-lowering therapies in patients with previous myocardial infarction, there was no statistically significant reduction in the primary end point of major coronary events, but there was reduced risk of other composite secondary end points and nonfatal acute MI. There were no differences in cardiovascular and all-cause mortality. The results indicate that patients with myocardial infarction may benefit from intensive lowering of LDL-C without increase in noncardiovascular mortality or other serious adverse reactions,- the researchers conclude. Christopher P. Cannon, MD, of Brigham and Women's Hospital and Harvard Medical School, Boston, discusses the results of the study by Pedersen et al. "What are the messages for patients from the IDEAL and other statin trials? First, for the 'bad' cholesterol, LDL-C, lower is better for preventing MI stroke, need for cardiac procedures, and death. Second, statins are safe overall, even for patients with extremely low treatment LDL-C levels. However, patients and physicians have to work as partners to monitor for adverse effects, which can occur in up to 5 percent of patients but that only rarely can be life-threatening. Fortunately, these are almost always reversible and do not lead to any permanent damage. Third, patients should know their cholesterol numbers, for both LDL-C and HDL-C, to enable them to see how much lowering is needed to reach targets of an LDL-C level of less than 100 mg/dL for patients with risk factors or less than 70 mg/dL for patients with heart disease." "And fourth, any drug treatment should be taken together with an appropriate diet and exercise program to lower cholesterol and overall vascular risk. The amount of LDL-C lowering with diet is only in the range of 7 percent to 12 percent. Clearly, diet is a central part of the treatment, but to get the benefits of very low cholesterol levels, drug treatment is often necessary. Optimal use of diet and appropriate use of medications will dramatically reduce the risk of MI, stroke, and death from heart disease. These new data should help motivate any patients who have been hesitating about treating their cholesterol to talk with their physician to get the benefits of intensive cholesterol lowering." "Finally, the scientific community needs to continue to pursue new avenues of treatment, with approaches that may well be 'beyond statins.' Even with intensive statin therapy, the current best evidence-based treatment available, many patients still will have recurrent cardiovascular events. New strategies may include development of new agents to achieve even lower target LDL-C levels, substantially increase HDL-C levels, reduce triglycerides, reduce C-reactive protein and other components of inflammation, and modify many other identified components of vascular disease," Dr. Cannon writes. Source: JAMA.2005; 294:2437-2445, 2492-2494. Doctors and Patients Should Discuss Use of Alternative Medicines According to the Medical Dictionary Online, alternative therapies are practices which are not currently considered an integral part of conventional medical practice and are used instead of conventional treatment. As the use of alternative medicines increases, physicians must be more active in determining what their heart patients should take and educating them on the risks, according to new research reported at the American Heart Association’s Scientific Sessions 2005. Depending on the alternative medication, there can be life-threatening interactions with prescribed cardiac medications, said Beth Abramson, MD, FRCP, FACC, lead author of the study and director of the Cardiac Prevention Center at St. Michael’s Hospital in Toronto. What is striking is the number of heart patients taking these types of medications and not talking to their doctors about it, she said. Some of these patients are on multiple prescribed heart medications. Abramson, an assistant professor of medicine at the University of Toronto, advises heart patients to give their doctors a list of the complementary or alternative medicines they are taking. According to researchers the use of complementary and alternative medicines continues to grow in North America and they find it surprising that reasonably educated populations, who are on multiple heart medications, also are taking alternative medications without talking to their doctor. There are specific interactions with cardiac drugs that could make alternative medicines dangerous, Abramson said. Patients are hearing about these alternative therapies from the lay press and friends. No doubt, in the time of instantaneous information on the Internet, patients must be cautious where they gather their information. For example, certain herbal preparations interfere with cardiac drugs. Hawthorne berries may be dangerous to heart patients on prescribed drugs. Medications containing licorice affect high blood pressure. St. John’s wort interferes with levels of heart drugs such as digoxin and warfarin. In a study of 308 heart patients, using standardized interviews, the Toronto researchers found that 45 percent of patients used complementary or alternative medicines (CAM). The majority of the therapies was herbal medications, vitamins and minerals. Yet, only 56 percent of CAM users’ heart specialists and 75 percent of family doctors were aware of the use. Researchers found that only about eight percent of specialists and 13 percent of family doctors inquired about what alternative medicines patients were taking. Only 39 percent of CAM users believed it was important for their physicians to know about such usage. Fifty percent of CAM users in the study claimed they were aware of the risks of using alternative medicines. More than half of patients using CAMs received information on the use of these medications through the news media or friends. Only 21 percent received information prompting usage from their physicians. In the era of evidenced-based medicine, we have more patients who are quite comfortable with alternative medicine rather than drugs proven to work, Abramson said. Unfortunately many patients believe that if something is natural, then it’s safe. But many of these alternative medicines are not regulated, aren’t necessarily safe and many have not been proven effective. Could Cell 'Recycling' Regenerate Ailing Hearts? Heart attack survivors infused with stem-like cells from their own bone marrow had nearly twice the improvement in their heart's pumping ability as patients given a placebo, a researcher announced in a late-breaking clinical trial session at the American Heart Association’s Scientific Sessions 2005. A subgroup analysis found that the benefits seen four months after a heart attack appeared to be most pronounced in patients with large heart attacks, those that produced greater damage to the heart muscle, said Volker Schachinger, MD, professor at the J. W. Goethe University in Frankfurt, Germany, and the Third Medical Clinic of Cardiology. Schachinger is lead author of the report from the Intracoronary Infusion of Bone Marrow-Derived Progenitor Cells in Acute Myocardial Infarction: A Randomized, Double-Blind, Placebo-Controlled Multicenter Trial (REPAIR-AMI). The trial is the world's largest, placebo-controlled study of the cell therapy that has shown widely mixed results in prior, smaller studies. "The REPAIR-AMI trial may be a landmark in helping to determine whether the concept of progenitor therapy will have a future for restoring heart function after acute myocardial infarction," Schachinger said. The study involved 204 patients at 17 medical centers across Europe. All patients received the cells after having a heart attack. Half of them received infusions into their hearts of mononuclear progenitor bone marrow cells (BMC) isolated from their own bone marrow. The other half received placebo infusions. The primary endpoint was global improvement of left ventricular function, a surrogate predictor of patients' prognosis after a heart attack. The two groups had virtually the same left ventricular ejection fraction (LVEF) at the start of the study. The LVEF was 47 percent in the placebo group and 48 percent in the BMC group, he said. After four months, both groups had improved as expected. But improvement was nearly twice as great in the BMC group. The increase in LVEF was 5.5 percent on average to a total LVEF of 54 percent, compared to an improvement of three percent on average to an LVEF of 50 percent in the placebo group, he said. Secondary endpoints were equally encouraging, he said. The researchers found indications that BMC patients had less heart enlargement compared to placebo patients. The researchers also found that BMC patients had significantly improved blood flow reserve in the artery where the heart attack occurred, indicating the possible creation of new blood vessels to nourish the damaged area of the heart. The beneficial effects on heart remodeling were also reflected in a reduction among BMC patients in a composite endpoint that included death, new heart attacks and hospitalization due to heart failure, he said. "Progenitor cell therapy after a heart attack is a new therapeutic strategy that completely differs from all the therapeutic options we have so far," said Andreas M. Zeiher, MD, senior author of the study and a professor at J. W. Goethe University in Frankfurt, Germany, and director of the Third Medical Clinic of Cardiology. "The medications and interventional therapies available so far are intended only to limit further damage to the heart. In contrast, progenitor cell therapy has the potential not only to limit damage, but to regenerate heart function," he said. "Thus, if stem/progenitor cell therapy will work, this may have a major impact on public health." This experimental therapy is often casually referred to as "stem cell therapy." But there are distinctions between progenitor cells and stem cells, Schachinger said. Stem cells are those that can adapt into various other kinds of cells, such as muscle and bone. "There are different stages of the 'stemness' of cells," he said. "The nearer stem cells are to being dedicated to certain tissue, the more they lose their stemness capacity. Often the term 'progenitor cells' is used to describe 'more dedicated' stem cells." After encouraging test results in the lab, stem/progenitor cell therapy has had mixed results in humans, with some studies showing positive effects and others showing none. Controversies about the mechanisms of intracoronary progenitor cell therapy are ongoing, he said. "Whereas experimentally, transdifferentiation of a progenitor cell into a cardiac muscle cell has been demonstrated in scientific models, there is heavy dispute over whether it occurs, or even if it may play a relevant role in humans, he said. But there are other potential effects of progenitor cells applied to the heart, including paracrine effects (release of cytokines), creation of new blood pathways and others," he said. The Transradial Approach and Same-Day Coronary Stenting: The EASY Trial The EArly Discharge after Trans-radial Stenting of CoronarY Arteries (EASY) Randomized Trial, suggests a new approach which could turn those procedures into day surgery. The findings are being presented at a late-breaking clinical trial session at the American Heart Association’s Scientific Sessions 2005. We propose a practice with more comfort for the patients, less risk of complications and greater cost-savings due to shorter hospitalizations, said Olivier Bertrand, MD, PhD, assistant professor, faculty of medicine, Laval University in Quebec City, Canada, and interventional cardiologist at Laval Hospital. In EASY “an open-label, randomized study on 1,005 patients “ researchers compared two treatments. One treatment group received a bolus of abciximab to reduce the risk of blood clots and was discharged 4-6 hours later. The other treatment group received an initial dose and a perfusion, and remained hospitalized overnight. In addition, 343 patients had predefined complications after angioplasty (per the registry) and received 12-hour infusions and hospitalization, as required. The group that received the single bolus was discharged the same day and fared as well after 30 days as those who got the infusion, Bertrand said. The primary composite end-points included death, heart attack, the need for urgent revascularization, repeat hospitalization, major bleeding, access site complications and severe thrombopenia at 30 days. The rate of events after adjudication was 13.5 percent in the single-dose group and 10.2 percent in the bolus plus infusion group. As expected, the difference between the two randomized groups was small and statistically non-significant, Bertrand said. The results held up at six months and the researchers are continuing to follow the patients, Bertrand added. The researchers also calculated secondary end-points similar to other studies which included death, heart attack or revascularization of the dilated vessel at 30 days and six months. The secondary composite end-point after adjudication was 1.6 percent in the bolus group and 1.8 percent in the bolus plus perfusion group. No deaths occurred. Of the 504 patients in the bolus group, 445 (88 percent) were discharged home the same day. At six months, death, heart attack or revascularization of the dilated artery was 5.9 percent in the bolus group and 5.6 percent in the bolus plus perfusion group. Both randomized groups had a lower number of events at 30 days and 6 months than in the registry (11.7 percent at 30 days and 20.2 percent at six months). A previous study [Evaluation of 7E3 for the Prevention of Ischaemic Complications (EPIC)] assessed the use of abciximab in the treatment of high risk patients undergoing percutaneous revascularization procedures. EPIC showed that the single dose plus 12-hour drip of abciximab reduced complications after angioplasty and was superior to the strategy of a single bolus. However, the study was performed before stents became commonplace. Therefore, it was time to revisit the question, Bertrand explained. In addition to changing the abciximab dosing, another major change is needed to make angioplasty plus stenting feasible as same-day surgery. The use of the trans-radial approach instead of the traditional femoral approach has been associated with fewer complications and increased patient satisfaction, yet it is rarely used in the United States, Bertrand said. Because a smaller artery is used, there is less risk of bleeding at the insertion point, which can be closed with a simple bandage. Patients can stand up immediately after the procedure. In part because of concern over navigating in the smaller vessel, which requires specific training, trans-radial catheterization is used in less than 10 percent of U.S. stenting procedures. While its use is slowly increasing in Europe and Asia, doctors there employ it only 10 percent to 30 percent of the time. Drug-coated stents are considered too expensive for routine use by most health systems around the world. However, if the same-day surgery approach can reduce the amount of money used for medication and hospital stays, perhaps those funds could be reallocated elsewhere, he explained. We have shown that there is no penalty for patients who skip perfusion of abciximab in cases of uncomplicated procedures, Bertrand said. The next step would be to repeat this study as a large, multicenter trial. NHLBI Research Highlights at American Heart Association’s Scientific Sessions: Findings on Women and Heart Disease, Metabolic Syndrome in African Americans, Impact of Sodium Reduction on Risk of Cardiovascular Disease or Death At this year’s American Heart Association’s Scientific Sessions in Dallas, scientists supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health presented the latest research findings, including studies on women and heart disease, the extent of metabolic syndrome among African Americans in the Jackson Heart Study, and the impact of sodium reduction on the risk of cardiovascular disease. Postmenopausal women with higher levels of male sex hormones levels have greater prevalence of coronary artery disease. The relationship between male sex hormones called androgens and atherosclerosis in women is poorly understood. Some studies have found an increased risk of coronary artery disease in women who have high levels of androgen, such as those who have polycystic ovary syndrome. Scientists with the Women’s Ischemia Syndrome Evaluation (WISE) study analyzed blood hormone levels of 400 women (296 postmenopausal and 104 premenopausal) undergoing coronary angiography for suspected myocardial ischemia. Hormones measured included estradiol, estrone, FSH, LH, free testosterone, sex-hormone binding globulin, androstenedione, and DHEA-S. Glucose and insulin were also measured. The investigators found that among postmenopausal women, higher levels of free testosterone and androstenedione are associated with greater coronary artery disease as shown in angiography. These associations are independent of cardiac risk factors. The scientists found no similar relationship in premenopausal women. Importance of socioeconomic status in predicting heart attack and cardiovascular death in women. The strong relationship between socioeconomic status (SES) and cardiovascular disease is known. However, the impact of SES on heart attacks and cardiovascular death in women is complex, as women are more likely to live in poverty than men. To help clarify this complex relationship, Women’s Ischemia Syndrome Evaluation (WISE) study investigators explored the relative contributions of SES factors compared to traditional heart disease risk factors on heart attack and death in 819 women. Through exams, medical histories and records, questionnaires, and angiography, the scientists obtained extensive information on such SES factors as ethnicity, marital status, highest level of education, retirement status, income, and health insurance coverage. During the 5 years of follow-up, there were 92 deaths or heart attacks. In general, women with the following characteristics were more likely to have negative heart-related outcomes: less than a 9th grade education, being African American, Hispanic, Asian, or American Indian, on public insurance, unmarried, with annual household income less than $20,000, disabled, employed less than full time, and in service or technical jobs. An evaluation of all SES factors revealed that insurance status and income were the single greatest predictors of a participant’s cardiovascular status. When the scientists controlled for severity of coronary artery disease as shown on angiography, income remained a significant predictor of cardiovascular death and heart attack. The scientists predicted that survival without a heart attack ranged from 86 percent to 98 percent for women earning less than $20,000 to over $100,000 per year respectively. More than one-third of African Americans in Jackson Heart Study have metabolic syndrome. Among the 5,296 participants in the longitudinal observational study of African Americans and heart disease, 36 percent of men and women had metabolic syndrome at the baseline visit. The prevalence increased according to the age of participants: 15.5 percent of participants aged 20-35, 38 of those between 45-64 and 45 percent of participants 65 and older. The syndrome was more prevalent among women (40 percent) than men (29 percent). Obesity and high blood pressure were the most common indicators of metabolic syndrome in this cohort. Also, 44 percent of participants had low HDL cholesterol. It is well known that the individual risk factors of hypertension and obesity are highly prevalent among blacks, but this paper dramatically underscores how frequently they occur together, each factor compounding the risk of the other metabolic syndrome characteristics. Also surprising is the relatively high prevalence of low HDL cholesterol, since traditionally, it has been reported that African Americans have higher HDL levels than their non-African American counterparts in the US. Reducing dietary sodium reduces CVD risk by 26 percent. Research has shown that reducing sodium has a direct affect on lowering high blood pressure. But does this dietary intervention have a similar affect on cardiovascular disease risk? In a randomized trial of men and women ages 30-54 with prehypertension, risk of total cardiovascular disease or death was reduced by 26 percent among those who followed a reduced sodium diet. The Trials of Hypertension (TOHP) follow-up study evaluated patient outcomes 9-14 years following the dietary interventions. Scientists conclude that a higher average intake of sodium may be associated with increased risk of cardiovascular events. Data Demonstrate Major Risk Stratification Benefits of Lp-PLA2 in Diabetic and ACS Patients Two studies presented at the AHA demonstrated that high levels of the pro-inflammatory enzyme, lipoprotein-associated phospholipase A2 (Lp-PLA2), are associated with an increased risk in cardiovascular disease across multiple populations. The first study showed that in diabetic patients, Lp-PLA2 conferred a greater than 2-fold increase in risk of coronary artery disease (CAD) or death from CAD, independent of traditional risk factors. A second study described Lp-PLA2’s value for predicting recurrent events in patients presenting with acute coronary syndromes (ACS). In the first study, researchers from LDS Hospital and University of Utah in Salt Lake City, evaluated whether the predictive value of Lp-PLA2 for angiographically confirmed CAD differs in patients by glycemic or diabetic status. Lp-PLA2 levels were measured in 1,493 patients (average age 63 years with 70% male) enrolled in the Intermountain Heart Collaborative Study using the PLAC® test (diaDexus, South San Francisco, CA). All patients underwent coronary angiography to diagnose the presence of CAD, and were categorized by fasting glycemic status for presence of diabetes mellitus. They were then followed for an average of seven years to determine CAD death incidence. After adjustment for traditional risk factors, Lp-PLA2 levels predicted a greater than two-fold risk in CAD (odds ratio = 2.10, p=0.05) and in CAD death (hazard ratio = 2.29, p=0.02), in patients with diabetes. We found that Lp-PLA2 was a strong and significant predictor of angiographic CAD and CAD death in patients with clinically diagnosed diabetes mellitus over a seven year period, stated Jeffrey Anderson, MD, associate chief of cardiology at LDS Hospital and senior investigator on the study. This data highlights the potential importance of the PLAC test in a preventive testing regimen for diabetic patients, to better manage the cardiovascular risk commonly associated with diabetes. In the second study, researchers from medical centers in Germany and Australia set out to define, in a multi-marker approach, the role of Lp-PLA2 alongside high sensitivity C-reactive protein (hsCRP), D-Dimer, NT-proBNP, and troponin I in patients with ACS. The markers were measured in 429 consecutive patients (average age 60 years with 60.6% male) and results were correlated with incidence of a coronary event (including death, non-fatal myocardial infarction, unstable angina, PCI and CABG) at 42 days. The overall incidence of coronary events was 13.1%, reflecting a mild to moderate risk population. Lp-PLA2, BNP and troponin I were found to be effective and additive markers of risk stratification. Lp-PLA2 was a better marker of risk than hsCRP in this patient population. Importantly, none of the clinical or ECG-variables of the TIMI risk score proved to be of comparable significance in risk stratification.
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