Keeping you up to date on recent headlines in cardiovascular healthcare:
Heart screening: unnecessary for Type 2 diabetics without symptoms . . . . Routine screening for coronary artery disease in Type 2 diabetes patients with no symptoms of angina or history of coronary disease is unnecessary and may lead initially to more invasive and costly heart procedures, according to researchers at Yale School of Medicine (New Haven, Connecticut). The researchers spearheaded the Detection of Ischemia in Asymptomatic Diabetics study of 1,123 participants randomly assigned to either a screening stress test that looks at the blood flow to the heart, or to a group not screened. They found that routine screening of Type 2 diabetics identifies a small group of patients at higher risk, but does not significantly affect overall outcome. The findings were reported in the April 15 Journal of the American Medical Association.
Scientists discover genetic variant tied to increased stroke risk . . . . Millions of people have a genetic variant linked to increased risk of ischemic stroke, reports an international research team including scientists at the University of Texas Health Science Center at Houston in a study published online April 15 by The New England Journal of Medicine. Data from four large genome-wide association studies in the United States and Europe revealed that about 20% of whites and 10% of blacks have at least one copy of this genetic variant and that each copy increases the risk of ischemic stroke by about 30%. The variant was found on chromosome 12 near one gene associated with brain injury repair called NINJ2 and another connected to blood pressure control called WNK1. The variant was found during an analysis of the genomes, or DNA, of almost 20,000 individuals from the U.S. and Europe, the study including both whites and blacks. The variant was not associated with increased risk for non-ischemic stroke.
Immune cells protect brain from further damage after stroke . . . . Scientists at the Neurology Clinic of the Heidelberg University Hospital (Heidelberg, Germany) say that for the first time they have shown that certain immune cells in the blood inhibit inflammation after a stroke. These cells are known as regulatory T lymphocytes (Treg). The researchers have shown that a stroke in mice with no functioning Treg cells in their blood causes much greater damage to the brain and greater disabilities than in animals with functioning Treg cells. An analysis showed that mice without this cellular "first aid" produce much more inflammatory transmitters in the brain and blood. The regulator cytokine Interleukin 10 plays an important role in this protection, offering a possible approach to stroke therapy. The study has been published in Nature Medicine.
How life-threatening blood clots take hold . . . . A study by researchers at Tufts Medical Center and Tufts University School of Medicine (Boston) indicates that, in addition to thrombin, matrix metalloprotease enzymes are important players in platelet function and the biology of blood vessels. Two of those enzymes, MMP-1 and MMP-2 can actually encourage platelet activation, according to earlier studies, although the means were unknown. In cancer cells too, MMP-1 activates a receptor known as PAR1. According to the researchers, PAR1 inhibitors being tested in clinical trials might have an added benefit. They say that exposure of platelets to collagen activates MMP-1, which in turn directly cut PAR1 on the surface of platelets. The study is reported in the April 14 issue of Cell.
Cardio effects of smoke from cigarettes, cooking oil, wood . . . . Secondhand tobacco smoke and smoke from cooking oil and wood smoke affected cardiovascular function of men and women who were exposed to small doses of the smoke for as little as 10 minutes, according to a study from the University of Kentucky (Lexington). The study showed that: cardiovascular responses during brief exposures were similar to those found during longer or higher-level exposures; the response occurs with different types of smoke (tobacco, cooking oil and wood smoke); men respond to environmental tobacco smoke with a greater increase in indexes of sympathetic outflow to blood vessels than do women. The sympathetic nervous system produces the "fight or flight" response, which drives the heart and blood pressure and may cause damage if activated too long. Women respond with a greater parasympathetic response, dubbed "rest and digest," which acts as a brake on the heart and blood pressure.
Angina, gastroesophageal reflux linked . . . . A research team at the Toho University School of Medicine (Tokyo) investigated the association between gastroesophageal reflux diseases (GERD) and coronary heart diseases. Among 712 patients (36%) with GERD, ECG was performed in 171 (24%), and ischemic changes were detected in eight (5%). Four (50%) of these patients with abnormal findings upon ECG had no chest symptoms such as chest pain, chest oppression, or palpitations. These patients (0.6%; 4/712) were thought to have non-GERD heartburn, which may be related to ischemic heart disease. Of the 281 patients who underwent ECG and did not have GERD symptoms, 20 (7%) had abnormal findings upon ECG. In patients with GERD symptoms and ECG signs of coronary artery ischemia, the prevalence of linked angina was considered to be 0.4% (8/1970 patients). The study was published in the April 14 issue of the World Journal of Gastroenterology.
UCLA wins grant for heart, stroke care for disadvantaged . . . . UCLA reported that it has been awarded a four-year, $3.89 million grant from the American Heart Association to establish a research center focused on improving the health of disadvantaged minority patients at risk for stroke and heart attack. In addition to training future scientists, the center will collaborate with community partners on two studies exploring how to prevent stroke survivors from suffering a second stroke. Principal investigator Dr. Barbara Vickrey and co-director Dr. Jeffrey Saver, professors of neurology at the David Geffen School of Medicine at UCLA, will lead the center with a team of faculty from the medical school and the UCLA School of Public Health, University of California at Los Angeles.
UK cardio research program funded . . . . A research program to increase understanding of why arteries stiffen and how this stiffening contributes to cardiovascular disease, and to identify new medical treatments, has been launched in London with £750,000 in funding. Through the ARTerial Inflammation, Stiffening and Calcification (ARTISTIC) program, researchers and clinicians at King's College London and Guy's and St Thomas' NHS Foundation Trust, hope to increase understanding of the causes of arterial calcification. The program is one of eight recently funded through the comprehensive Biomedical Research Centre at Guy's and St Thomas' and King's College intended to discover advances in clinical care.
– Compiled by Don Long, MDD National Editor