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Answer. Two major activities are continuing. First, an electrically powered, implantable left ventricular assist system (LVAS) has completed rigorous laboratory reliability tests that demonstrated two years of continuous operation without failure. The device is being prepared for clinical evaluation in patients with advanced congestive heart failure. It will be the first use of an LVAS designed for extended use that only requires externally worn batteries to transmit electrical energy across the intact skin to power the implanted device. Clinical Centers in Pittsburgh and St. Louis are collaborating with the New England Research Institute to develop the clinical evaluation protocols and to guide the Investigational Device Exemption (IDE) through the Food and Drug Administration (FDA). The first LVASS are expected to be available in a few months and will be finally tested in a series of animals. Following necessary approvals of all aspects of the program; patient implants should begin in the Spring of 1992.
Second, the program to develop an implantable, electrically powered artificial heart to replace the failing heart is in the fourth of six phases. To date, four concepts for an implantable system have been designed, and prototypes for them have been built. A reliability model has been established for each of the systems and production problems are being evaluated. Animal tests have begun to measure performance so that required improvements can be identified. The objective of the current program is to demonstrate the potential of the four systems to function safely and effectively in a clinical setting over a five-year lifetime.
Question. Have there been any recent major breakthroughs in technology regarding artificial hearts?
Answer. Recent clinical experience with a textured, blood contacting surface suggests that it may be possible in some implantable artificial heart systems to develop surfaces that are virtually free of thromboembolic complications. New blood pumping surfaces and stationary surfaces have been developed that permit the growth of a coating similar to the lining in a natural blood vessel. These new surfaces have been observed in three dozen patients bridged to cardiac transplant. The patients accumulated nearly five years of mechanical circulatory support without embolic complications. Their experience suggest that synthetic surface receptors could evolve to the point where they respond favorably to a changing biological environment and remain biocompatible for the lifetime of the implant.
CHOLESTEROL LEVELS IN SPECIAL POPULATIONS
Question. Are elevated blood cholesterol levels predictors of cardiovascular disease in older persons, women, and minorities?
Answer. Data from 22 U.S. and international studies on cholesterol as a risk factor for heart disease in older persons and women were recently reviewed at an NHLBI-sponsored workshop. They strongly support cholesterol as a risk factor in older men and in middle-aged women. Risk of fatal coronary disease was 32 percent higher in men over age 65 years with cholesterol levels of 240 mg/dl or more, compared with those with cholesterol levels of 200 mg/dl or less. In women under age 65 years, the risk of fatal coronary disease was' more than twice as high among those with cholesterol levels of 240 mg/dl or more when compared to those with cholesterol levels below 240 mg/dl. In women over age 65 years, however, data were much less consistent and fewer studies were available. Although the overall risk of fatal coronary disease was only marginally increased in women over age 65, it was approximately 12 percent higher in those with elevated cholesterol levels. Further data are needed to evaluate the cholesterol-heart disease association in older women. They are currently being collected in NHLBI-sponsored, multi-center studies such as the Cardiovascular Health Study, the Cholesterol Reduction in Seniors Program, and the Framingham Heart Study.
Data for minority groups and for overseas populations were similar to those for White persons in the United States. Risk estimates for cholesterol levels greater than 240 mg/dl compared to cholesterol levels less than 200 mg/dl were essentially identical among 22,000 Black, 6,600 Hispanic, 4,000 Asian, and 316,000 White middle-aged men screened for entry into the Multiple
Risk Factor Intervention Trial (MRFIT), although overall rates of heart disease were lower in the minority subjects. Further assessment of risk associated with elevated cholesterol levels in minority populations will be provided by NHLBI-sponsored studies such as the Strong Heart Study, the Honolulu Heart Program, CARDIA, and the Atherosclerosis Risk in Communities Study (ARIC).
DIETARY RECOMMENDATIONS FOR CHILDREN
Question. Do you recommend the promotion of low fat, low cholesterol diets among children as a way of preventing heart disease later in life?
Answer. The National Cholesterol Education Program's (NCEP) Population Panel recommends that all healthy Americans, including children over the age of two, follow a dietary pattern lower in saturated fats, total fat and dietary cholesterol than the typical American diet, as a way to prevent coronary heart disease (CHD). The Panel recognizes that the caloric and nutrient needs of growing children are critical to support normal growth and development, and therefore urges prudent movement to the recommended eating pattern. Also, the NCEP Expert Panel on Blood Cholesterol Levels in Children and Adolescents recently released its report. This group reviewed the scientific evidence that atherosclerosis or its precursors begins in childhood and makes recommendations for the detection, evaluation, and treatment of children and adolescents believed to be at risk for CHD later in life by virtue of family history, and elevated levels of low density lipoprotein (LDL) cholesterol. The report also provides strategies for encouraging desirable eating patterns for healthy children and adolescents.
To determine the safety and efficacy of a diet lower in saturated fats, total fat, and dietary cholesterol in growing children, the Institute funds a multi-center, clinical trial, The Dietary Intervention Study in Children (DISC). Since children enrolled in DISC have elevated LDL levels, the diet recommended is more restricted in saturated fats, total fat, and dietary cholesterol than the diet recommended for healthy children. The DISC children will be followed for a minimum of three years to determine the effect of a fat restricted diet on LDL, growth, development, micronutrients, behavior, and cognition.
SALT AND HYPERTENSION
Question. There seems to be some controversy about the role of salt in raising blood pressure. What do the studies actually show?
Answer. The results of the most relevant studies, recently published following a 1989 NHLBI, reaffirm the importance of salt. Data from 15 observational population studies and 24 clinical trials were analyzed. One of the population studies, called INTERSALT, included 52 centers in 32 countries. In the aggregate, these studies indicated average blood pressures were lowered by approximately 2-4 millimeters of mercury when the usual sodium intake was cut in half. The benefits were somewhat greater in hypertensives. Results of observational studies and trials are remarkably consistent. Blood pressure reductions of these magnitudes might reduce death from heart attacks by 5 percent and death from stroke by percent. The potential number of U.S. deaths averted in middle-age alone is estimated to be 16,000 per year.
The conference papers also included studies of so-called "salt sensitivity", which is the tendency of people to respond differently to large changes in salt intake and urinary excretion over relatively short periods. These findings have considerable importance for understanding mechanisms of blood pressure regulation.
LOW BLOOD CHOLESTEROL
Question. It has been reported that lowering cholesterol may result in violent behavior. Is this a source of concern?
Answer. At the present time, a link between lowering of blood cholesterol and so-called "violent behavior" is only hypothetical. Last fall, the
British Medical Journal published a review article which used a mathematical approach to reanalyze the data from several primary prevention trials on coronary heart disease. The authors found that lowering cholesterol does, in fact, decrease the number of deaths from heart attacks. However, they also noted that the number of deaths due to homicides, accidents, and suicides were increased among people being treated for high cholesterol.
We are not sure what this means for several reasons. First, this was a retrospective analysis of data not collected for the purpose of answering this question; an independent study would be needed to determine whether the finding is real or merely an artifact. Second, no increase in these "violent" deaths was found in secondary prevention trials; that is, in studies that lowered cholesterol among heart attack survivors. We do not understand why this difference between primary and secondary prevention trials exists.
It should be noted that a number of scientists dispute the interpretation of a link between "violent" deaths and lowered blood cholesterol. Nevertheless, the hypothesis is an interesting one, and warrants further investigation.
CONGESTIVE HEART FAILURE
Question. Recently we heard much about congestive heart failure. What is the status of your research in this area?
Answer. The National Heart, Lung, and Blood Institute maintains an active and growing research portfolio on congestive heart failure (CHF). Studies of cardiac pathophysiology have already provided a comprehensive description of the hemodynamic and electrical factors related to worsening function of the failing heart. New studies apply recent developments in genetic engineering, cardiac imaging and spectroscopy to fundamental questions about signals for the structural changes in CHF, the role of recently discovered vascular hormones, and changes in the availability of cellular energy in failing heart.
One promising line of research concerns the increase in autonomic nervous system (ANS) hormones that accompanies CHF. NHLBI-supported studies have clearly demonstrated an association between increased ANS hormones and clinical decline in CHF patients. The Institute supports a number of studies on the fundamental mechanism responsible for ANS activation, and much new information has been gathered that will be essential in the development of new pharmacologic treatments. Another line of NHLBI-supported research concerns the new group of drugs called angiotensin converting enzyme (ACE) inhibitors. The drugs improve clinical function and well-being among CHF patients. Preliminary evidence suggests that they may also prolong life. The NHLBI supports a major clinical trial to address the effectiveness of ACE inhibitors in patients with varying degrees of CHF.
TREATMENT OF MILD HYPERTENSION
Question. Is drug treatment safe and effective for the treatment of mild hypertension?
Answer. In April 1990, an overview, or statistical summary, of all properly designed clinical trials of antihypertensive drug treatment was published in the British Journal, The Lancet. This report affirmed results of earlier, more limited reviews: cardiovascular mortality is significantly reduced by treatment. Further, the benefit to mild hypertensives was the same when compared to all hypertensive patients.
What is the place of nonpharmacological treatment?
Answer. Nonpharmacologic treatments can be useful in lowering blood pressure, particularly in mild hypertension. Recent evidence from NHLBIsupported clinical trials suggests that a combination of nonpharmacologic intervention especially, modest weight reduction and a low-dose drug regimen is most beneficial, not only for lowering blood pressure, but also for minimizing drug side effects and improving some indicators of "quality-of
life". The regimens, which include moderate salt restriction, limited use of alcohol, and increased physical activity, have now been maintained for several years in selected study populations.
NATIONAL HIGH BLOOD PRESSURE EDUCATION PROGRAM
Question. Your Institute's National High Blood Pressure Education Program is almost 20 years old. Aren't physicians sufficiently well-versed by now in managing hypertension?
Answer. It is true the NHBPEP has provided guidance to the clinical community on detection, evaluation and management of hypertension for quite some time. However, as our understanding of the disease increases, treatment choices expand, our knowledge about management increases, and the challenges to educate become more complex. Two decades ago, the program advocated a simple stepped-care management approach. All patients were prescribed one class of drug and if the blood pressure remained uncontrolled, a drug from a second class was added. If blood pressure was still uncontrolled, a drug from a powerful third class was added, and so on. Patients were simply counseled to tolerate the side effects. Many were not willing to do so and dropped out of care.
Today, a wide variety of treatment options and agents are available and the program is encouraging physicians to tailor therapy to the individual patient. Thus, not all patients will or should receive the same therapy. a result, side effects from treatment will decrease and adherence to therapy will increase. Tailoring therapy means that clinicians can offer patients greater choices and options, but it also means that they must expend additional efforts to understand all the differences among rationales for these options. In summary, treatment today is much more complex than it was two decades ago because of the wider variety of choices; it is also much more effective.
NATIONAL CHOLESTEROL EDUCATION PROGRAM
Question. What is the National Cholesterol Education Program doing to improve the management of high blood cholesterol?
Answer. Since the publication of the National Cholesterol Education Program's Adult Treatment Panel (ATP) guidelines in 1988, a major effort has been made to improve high blood cholesterol management. In 1989, visits to physicians for high blood cholesterol were up over nine-fold compated to 1983. The results of a new survey of physician knowledge, attitudes, and practice conducted in 1990 will be available at the time of the National Conference on Cholesterol and High Blood Pressure Control in April, 1991. A Cholesterol Education Program for Nurses was developed in cooperation with the American Heart Association (AHA), and a Dietitian's Kit was distributed to over 17,000 dietitians. New data fact sheets were developed to highlight the striking prevalence of high blood cholesterol. A booklet of dietary advice for patients with high blood cholesterol who have low literacy skills' was prepared, and the program's very popular dietary booklet (Eating to Lower Your High Blood Cholesterol) was widely distributed. A joint NHLBI-AHA joint "white paper" demonstrating the strength of the scientific basis for cholesterol lowering has been published and is being distributed to 180,000 physicians. The Institute conducted three important workshops addressing the issues of cholesterol as a CHD risk factor in older persons and in women; the cost and health implications of cholesterol lowering; and low cholesterol and health risk. Collectively, they supported the basic program directions of the National Cholesterol Education Program (NCEP). The NEP also released the final report of its Laboratory Standardization Panel. The report of the Panel on Children and Adolescents is nearing completion and will be released at the National Conference in April.
Question. What is the future direction of the National Cholesterol Education Program?
Answer. At this point, the National Cholesterol Education Program (NCEP); is planning to continue its high-risk and population strategies, while
refining its messages in several areas. The Institute, together with the American Heart Association (AHA), will sponsor a conference to address cholesterol lowering in coronary heart disease patients. A second conference is planned on the controversial issue of high triglycerides/low HDL. The results of these two conferences will be incorporated into the work of a new Adult Treatment Panel, which will address these and other important issues as it updates the current guidelines for the detection, evaluation, and treatment of high blood cholesterol in adults. A separate working group will make recommendations on standardization of HDL, triglycerides, and LDL measurements. Industry will be encouraged to promote heart-healthy eating patterns. New booklets will be distributed to help parents in encouraging heart-healthy eating by their children. A family theme will be used to tie together the various messages of the program. New survey information on the knowledge, attitudes, and practices of physicians, nurses, dietitians, and the public, and on blood cholesterol levels will be used to guide the efforts of the NCEP as it becomes available.
NATIONAL BLOOD RESOURCE EDUCATION PROGRAM
Question. How is the National Blood Resource Education Program helping to increase the numbers of blood donors?
Answer. The National Blood Resources Education Program's (NBREP) public education campaign seeks to encourage eligible individuals to give blood regularly to help save the lives of others. A mass media campaign, consisting of radio and print public service announcements has reached approximately 8,000 radio stations and 300 magazines. The campaign has also been seen in several major airports.
Activities to help improve blood donor recruitment and retention efforts by blood centers are underway. A publication, "Together Building a Blood Supply: A Guide to Donor Recruitment and Retention" has been distributed to individual blood centers. In addition, a symposium for donor recruiters and their top administrators was held in October, 1990, to explore the current issues in effective donor recruitment. Emphasis was placed on using a marketing approach and providing customer service in donor recruitment and retention. The program is currently assessing the effectiveness of these activities.
MINORITY BONE MARROW DONORS
Question. How are you helping to increase the number of minority donors in the bone marrow donor registry?
Answer. We are developing a mass media campaign to encourage Black and Hispanic persons to join the bone marrow donor registry of the National Marrow Donor Program. The campaign will include radio and print messages and will be localized and distributed to 13 marrow donor centers. In addition, a package will be developed to help donor centers prepare minority volunteers for recruitment efforts in their communities. The program will also include a symposium to acquaint donor centers with the available media tools and with specific techniques for reaching minority individuals in their communities. The effectiveness of this comphrehensive effort will be evaluated and the results will be used to revise the materials. Future efforts will involve the recruitment of other minority groups, such as Asians and Native Americans.
NATIONAL ASTHMA EDUCATION PROGRAM
Question. Your National Asthma Education Program is relatively new. Tell us about its goals and what are the accomplishments so far?
Answer. The National Asthma Education Program (NAEP) was launched in March 1989, to increase awareness that asthma is a serious chronic disease; to ensure that asthma symptoms are recognized by patients, families and the public and properly diagnosised by health professionals; and to ensure the effective control of asthma by encouraging a partnership among patients, physicians, and other health professionals through modern treatment and education programs. Achieving the NAEP goals will not only enhance the