August 10, 2007, 7:10 AM CT

High blood pressure, low energy- a recipe for heart failure

Aug. 10, 2007 -- A number of people with long-standing hypertension develop heart failure. But some don't. Daniel P. Kelly, M.D., and his colleagues at Washington University School of Medicine in St. Louis and other institutions are trying to figure out what could explain that difference.

Their latest research reveals that impaired energy production in heart muscle may underlie heart failure in some hypertensive patients. The scientists assert that a molecular factor involved in maintaining the heart's energy supply could become a key to new approaches to prevent or treat heart failure.

The molecular factor, a protein called estrogen-related receptor alpha (ERR alpha), helps the heart keep up with energy-draining conditions like high blood pressure, which makes the heart work harder to pump blood.

In the recent issue of Cell Metabolism, Kelly and colleagues report that mice born without any ERR alpha developed symptoms of heart failure when their hearts were forced to pump against high pressure. The hearts of normal mice took that pressure overload in stride and stayed healthy. Those contrasting outcomes suggest that heart health greatly depends on ERR alpha.

"The stress of a cardiac pressure overload asks heart muscle to manufacture more high energy compounds, and without ERR alpha, they can't do it," explains Kelly, the Tobias and Hortense Lewin Professor and Chief of the Cardiovascular Division. "You could say that in hypertension conditions, the heart fails because it becomes energy starved. And if you could feed the heart by using a drug that enhances ERR, for example you might enable the heart to better keep pace with its energy requirements."........ Posted by: April      Read more         Source

August 8, 2007, 7:57 PM CT

Gender, Genes And Blood Pressure

A number of common diseases exhibit gender bias and gender differences have been observed in the development of hypertension (hypertension) and heart (cardiovascular) disease. Prior studies have reported that gender may affect vascular physiology and the body's response to some types of blood pressure medications. Eventhough gender is commonly accounted for in association studies, newer research has focused on identifying autosomal (not on the X or Y chromosomes) genes that contribute differentially to complex traits (blood pressure) or diseases (hypertension). In a new study, scientists examined the differential contribution of genetic factors involved in regulating blood pressure based on samples drawn from a large community. They found significant differences in genetic contributors to blood pressure in males versus females.

The study was conducted by Brinda Rana and Nicholas Schork, Department of Psychiatry; Paul Insel, Department of Pharmacology; and Daniel O'Connor, Department of Medicine; University of California, San Diego, La Jolla, CA. It is entitled, "Population Extremes-Based Approach Defines Gender Differences in Adrenergic and Renal Genes Contributing to Blood Pressure." The research is one of more than 100 presentations being offered at the conference, Sex and Gender in Cardiovascular-Renal Physiology and Pathophyiology, being held August 9-12, 2007 in Austin, TX. The event is the second scientific gathering to be sponsored by the American Physiological Society (APS; www.The-APS.org) this year......... Posted by: April      Read more         Source

August 8, 2007, 6:54 PM CT

Estrogen Deficiency, Obesity And High Blood Pressure

At menopause, women lose hormone protection against heart (cardiovascular) and kidney (renal) diseases, and are likely to become obese. A research team has tested the idea that estrogen deficiency in aged females may trigger the development of hypertension and obesity. The results of their study, using an animal model, suggest that estrogen depletion can have these effects.

The study is entitled, "Role of Estrogens in Postmenopausal Obesity and Hypertension." It was conducted by Lourdes A. Fortepiani and Huimin Zhang, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX. The team will discuss its findings as part of the upcoming conference, Sex and Gender in Cardiovascular-Renal Physiology and Pathophysiology, being held August 9-12, 2007 at the Hyatt Regency Austin on Town Lake in Austin, TX. The event is the second scientific gathering to be sponsored by the American Physiological Society (APS; www.The-APS.org) this year.

To test their theory the scientists used 24 aged female rats. The ovaries were removed from two-thirds of the group (ovariectomized; ovx) while the ovaries of the other third of the group remained intact and served as controls. The scientists subdivided the ovx rats, giving half of the ovx group estrogen while the other half remained estrogen depleted......... Posted by: April      Read more         Source

August 6, 2007, 5:41 PM CT

High Blood Pressure Problems Largely Misunderstood

The distrust of healthcare providers shown by people with hypertension impedes effective therapy, as emphasized in a new study published in Journal of the American Academy of Nurse Practitioners. In a systematic review and metasynthesis of eleven qualitative studies published between 2000 and 2005, including more than 500 patients, significant and problematic differences were identified in beliefs about the presence of symptoms, the need to take medications for the rest of one's life, and race-specific therapy plans.

Hypertension is a common but serious health problem that affects nearly one-third of all adults in the United States. It can be controlled, though not cured, through changes in lifestyle and the use of medications, which must be continued for life. Because of the need for long-term therapy, it is essential that patients and healthcare professionals work together to fight the disease. This synthesis of qualitative studies provides valuable information that will assist healthcare providers to better understand and manage conflicts between healthcare provider and patient perspectives of this condition.

"In the presence of ineffective partnering, differences between lay and professional beliefs about high blood pressure result in inadequate management of the disease," says study author Pam Schlomann, highlighting the need for greater cooperation in combating high blood pressure......... Posted by: April      Read more         Source

August 6, 2007, 5:39 PM CT

Biomarker For Heart Failure Predicts Risk Of Death

A potential new biomarker for heart failure may be more powerful than established measures in identifying patients at increased risk for death from several causes. In a report to appear in the Journal of the American College of Cardiology that has received early online release, an international research team describes finding that blood levels of a protein called ST2 both indicate the presence of heart failure among patient with shortness of breath and powerfully predict the risk that a patient will die during the following year. Improved understanding of how ST2 and other biomarkers reflect aspects of the hearts hormonal environment someday may allow clinicians to develop more effective, individualized therapy plans.

While we are now able to diagnose heart failure with great sensitivity using natriuretic peptide tests, we have miles to go before we can reduce the considerable risk that accompanies that diagnosis, says James Januzzi Jr., MD, of the MGH Cardiology Division, who led the study. Its highly likely that examining a patients pattern of several complementary biomarkers will be superior for predicting risk than using just one. If we could harness the information these biomarkers yield to better adjust therapies in the same way that antibiotics are chosen based on the organism causing the infection that would be revolutionary......... Posted by: April      Read more         Source

August 3, 2007, 5:03 AM CT

Many heart attack patients still not getting clot-busting treatment

Far more of todays heart attack patients receive emergency angioplasty therapy or clot-busting drugs to re-open their clogged heart arteries than even a decade ago, a new study finds.

But 10 percent of patients who could benefit from this urgent therapy which is known to save lives and prevent lasting damage to the heart muscle dont get it at all, the study shows.

And the chance of missing out on lifesaving emergency therapy was highest among those patients whose heart attack symptoms dont include typical symptoms like chest pain, those who didnt reach the hospital until six or more hours after the start of their attack, women, people over age 75, and non-white people.

The study, reported in the American Journal of Medicine by a team led by heart specialists from the University of Michigan Cardiovascular Center and the Yale University School of Medicine, is based on data from 238,291 patients who had had a type of heart attack for which this treatment is appropriate between 1994 and 2003.

Its the most current and comprehensive look at the use of emergency reperfusion a term that describes therapys that can break up blood clots and other blockages in the tiny blood vessels of the heart and restore blood flow to the heart muscle.

In the ten-year study period, the percentage of patients who could have received emergency reperfusion but didnt declined from more than 20 percent to 10 percent a notable achievement that the authors attribute to the increasing evidence of the benefit of emergency angioplasty, and the rise in the availability of the therapy at American hospitals and concerted national efforts to improve care......... Posted by: April      Read more         Source

August 1, 2007, 8:48 PM CT

Cholesterol-lowering drugs don't offset healthy choices

Within the medical field, it is often assumed that patients view cholesterol-lowering medications (or statins) as a license to eat whatever they like -- they figure their medicine has them covered, so a steak here and there wont hurt. However, a study reported in the recent issue of Mayo Clinic Proceedings finds that such patients dont tend to adopt unhealthy diets when prescribed statins.

Scientists also observed that some patients were placed on cholesterol-lowering drugs before theyd made a good faith effort at improving their lifestyle to better their health. And some said they would have preferred starting with lifestyle alterations rather than medication.

Devin Mann, M.D., lead author of the article on statin use, says physicians should reconsider how theyre treating patients who seek preventive care for cardiovascular disease, namely by giving up their long-held assumptions about them.

Physicians arent good at predicting patient behavior, so they should seek to form a partnership of trust with patients based on mutual respect and optimal communication, says.

Dr. Mann from Mount Sinai School of Medicine.

This study involved 71 patients who had been prescribed statins for the primary prevention of cardiovascular disease. Patients were interviewed at the time of prescription and three and six months later, when no significant change in saturated fat intake was noted......... Posted by: April      Read more         Source

July 29, 2007, 9:39 PM CT

Using stem cells to help heart attack victims

New research at The University of Nottingham is paving the way for techniques that use stem cells to repair the damage caused by heart attacks.

The research, funded with a grant of 95,000 the Biotechnology and Biological Sciences Research Council (BBSRC), is looking at the process that turns a stem cell into a cardiomyocyte the beating cell that makes up the heart.

The Nottingham scientists are in the process of developing a new system to monitor cardiomyocytes in real time as they differentiate from stem cells into beating heart cells. The system uses electrophysiology to record the electrical properties in a cell and will be the first time it has been used to study cardiomyocyte cells in the UK.

The scientists hope that their research could provide more detailed information on the electrical activity of stem cell derived cardiomyocytes. In the longer term, this could facilitate their use in regenerating the damaged hearts of heart attack victims.

Dr Chris Denning, of the Universitys Wolfson Centre for Stem Cells, Tissue Engineering & Modelling, said: Human embryonic stem cells promise unrivalled opportunities. However, they are difficult, time-consuming and expensive to grow in the lab.

"Our understanding of how to convert them into cardiomyocytes is poor. At the moment we only know how to produce a few million cardiomyocytes, but to treat just one heart attack patient, we may need one billion that all function in the correct way"......... Posted by: April      Read more         Source

July 25, 2007, 5:17 AM CT

ICDs effective in helping to prevent sudden cardiac death

High-risk patients with hypertrophic cardiomyopathy appear to have reduced risk of sudden cardiac death with an implantable cardioverter-defibrillator that terminates dangerous heart rhythm disorders, as per a research studyin the July 25 issue of JAMA.

Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death in young people, including trained athletes. HCM is a genetic disease in which the heart muscle thickens abnormally, which can interfere with the heart's electrical system, increasing the risk for life-threatening abnormal heartbeats (arrhythmias). Only in the last few years has the implantable cardioverter-defibrillator (ICD) been systematically used as a potentially life-saving therapy in high-risk patients with HCM, as per background information in the article. An ICD is a device designed to quickly detect a life-threatening, abnormal heart rhythm, and attempt to convert the rhythm back to normal by delivering an electrical shock to the heart. The effectiveness and appropriate selection of HCM patients for this treatment is not certain.

Barry J. Maron, M.D., of the Minneapolis Heart Institute Foundation, Minneapolis, and his colleagues examined the clinical risk profile and incidence and effectiveness of ICD intervention in patients with HCM. The scientists analyzed data from a multicenter registry of ICDs implanted between 1986 and 2003 in 506 patients with HCM, average age 42 years. Patients were judged to be at high risk for sudden death. Average follow-up was 3.7 years......... Posted by: April      Read more         Source

July 23, 2007, 6:40 PM CT

Low Cholesterol Levels And Cancer

Millions of Americans take statins to lower their cholesterol, but how low should you go" A number of scientific studies support the benefits of lowering low-density lipoprotein (LDL) cholesterol, and achieving low LDL cholesterol levels is one of the most important steps in preventing heart disease. New research, however, provides evidence for an association between low LDL levels and cancer risk.

The authors of the study, reported in the July 31, 2007, issue of the Journal of the American College of Cardiology (JACC), set out to understand how and why statins cause side effects, especially damage to the liver and muscle cells. The study findings support taking multiple medications rather than high-dose statins to minimize those side effects. The scientists did not expect to find the increased cancer risk (one additional incident per 1,000 patients) from low LDL levels, and additional studies have already begun to investigate this potential risk further. A key component in future studies will be to confirm the risk and to identify whether the risk may be a side effect of statins or just low LDL.

This analysis doesnt implicate the statin in increasing the risk of cancer, said lead author Richard H. Karas, M.D., F.A.C.C., professor of medicine at Tufts University School of Medicine. The demonstrated benefits of statins in lowering the risk of heart disease remain clear; however, certain aspects of lowering LDL with statins remain controversial and merit further research......... Posted by: April      Read more         Source