Keeping you up to date on recent headlines in cardiovascular healthcare.
ICDs may not benefit women as much as men, study finds ... A meta-analysis of previously published research in the Sept. 14 issue of Archives of Internal Medicine, one of the JAMA/Archives journals, has found that implantable cardioverter-defibrillators (ICDs) do not appear to benefit women with advanced heart failure. Hamid Ghanbari, MD, and colleagues at Providence Hospital Heart Institute and Medical Center (Southfield, Michigan), searched for randomized clinical trials of implantable defibrillator therapy for heart failure patients published between 1950 and 2008 that included data on the risk of death for female patients. Five eligible trials that included 934 women were identified. According to the article, none of the five trials demonstrated a significant benefit of defibrillator implantation over medical therapy for women. When the researchers pooled the data and performed a meta-analysis, the ICD was not associated with decreased all-cause mortality in women. Among the 3,810 men in the studies, however, a statistically significant decrease in death rate was found in each of the five trials alone and in the combined meta-analysis. According to the authors, there are several possible explanations for the gender differences in these results. Among patients with heart disease, women have about one-fourth the risk of sudden cardiac death as men. This may be because women have different patterns of arrhythmias and also because they have more co-existing illnesses that may increase their risk of death from other causes. Therefore, a larger study population may be needed to show any benefit of defibrillator implantation in women.
Paper shines favorable light on Genous stent ... A paper published online in the International Journal of Cardiology suggests that OrbusNeich's (Hong Kong) Genous Bio-engineered R stent is feasible and safe in patients who need coronary revascularization before undeferrable non-cardiac surgery and have to discontinue dual antiplatelet therapy. The paper, titled "A new approach to percutaneous coronary revascularization in patients requiring undeferrable non-cardiac surgery," is based on a study of 30 patients who needed coronary revascularization followed by an endovascular or surgical procedure. All of the patients were treated with the Genous stent, and there were no cardiac events reported at 30-days follow-up after surgery. The dual antiplatelet therapy was stopped before surgery, achieving an average antiplatelet therapy time of 12.2 +/- 3.9 days. The surgery was performed after antiplatelet therapy interruption at an average interval from revascularization of 17.2 +/- 3.9 days. "The literature on an optimal strategy for high cardiovascular risk patients requiring undeferrable surgery remains limited," said Federico Piscione, MD, of Federico II University (Naples, Italy), lead and corresponding author of the publication. "This study adds to the body of knowledge that this Genous healing stent could allow surgical procedures to be performed soon after stent deployment" and dual antiplatelet therapy discontinuation. According to the company, Genous is OrbusNeich's endothelial progenitor cell (EPC) capture technology that promotes the accelerated natural healing of the vessel wall after the placement of blood-contact devices such as stents. The technology consists of an antibody surface coating that attracts EPCs circulating in the blood to the device to form an endothelial layer that provides protection against thrombosis and modulates restenosis.
Surgery fears affect cardiac surgery referrals ... According to a study by doctors at the University of Michigan Cardiovascular Center (U-M Cardiovascular Center; Ann Arbor), overblown fears about surgical risk and lack of awareness about the risk of not operating are among the reasons only half of eligible patients were referred for mitral valve repair. According to the doctors, a leaking mitral valve can lead to fatigue, abnormal heart rhythms with irregular heart beats, and congestive heart failure. The longer the leak continues, the more likely there will be permanent heart damage. Among those who were not operated on, three-fourths of patients met at least one indication for surgery, according to guidelines from the American College of Cardiology (Washington) and the American Heart Association (Dallas). "In general, cardiologists tend to overestimate the risks of surgery and underestimate the potential benefits for patients," said lead author David Bach, professor of internal medicine at the U-M Medical School and a cardiologist at the U-M Cardiovascular Center. Researchers identified 300 patients with moderate to severe mitral regurgitation for the study in the Journal of the American College of Cardiology. Patients had been screened in the University of Michigan Echocardiography Laboratory. Among them, 188 patients had functional mitral regurgitation, but only 30 of those patients underwent surgery. Of the 112 patients with severe organic mitral valve regurgitation, just half had surgery. Surgical risk scores were no different among patients who underwent surgery compared to those who did not, according to the researchers.
'Teachable software' may help diagnose heart infections ... According to researchers at the Mayo Clinic (Rochester) "teachable software" designed to mimic the human brain may help them diagnose cardiac infections without an invasive exam. Those findings were presented last week at the Interscience Conference on Antimicrobial Agents and Chemotherapy in San Francisco. According to the researchers, Endocarditis, an infection involving the valves and sometimes chambers of the heart, can be a problem in patients with implanted medical devices. Diagnosis usually requires transesophageal echocardiography, an invasive procedure that also has risks, the researchers note. It involves use of an endoscope and insertion of a probe down the esophagus. The software program is called an "artificial neural network" (ANN) because it mimics the brain's cognitive function and reacts differently to situations depending on its accumulated knowledge. That knowledge or training is provided by researchers, similar to how a person would "train" a computer to play chess, by introducing it to as many situations as possible. In this case, the ANN underwent three separate "trainings" to learn how to evaluate the symptoms it would be considering. The Mayo Clinic team studied 189 patients with device-related endocarditis diagnosed between 1991 and 2003. The ANN was tested retrospectively on the data from these cases. When tested on cases with known diagnosis of endocarditis, the best-trained ANN was correct most of the time (72 of 73 implant-related infections and 12 of 13 endocarditis cases) with a confidence level greater than 99%. The researchers also said that, when used on an overall sample that included both known and unknown cases, the ANN accurately excluded endocarditis in at least half of the cases, thus eliminating half the cohort from a needless invasive procedure.
British researchers say athletes should be screened for heart abnormalities ... According to the British Journal of Sports Medicine and the International Olympic Committee (IOC) young athletes should be routinely tested for heart abnormalities to prevent sudden cardiac death that is triggered by vigorous exercise, using a simple protocol, which includes a heart trace (electrocardiogram or ECG). This is the conclusion of several studies in the first of a series of quarterly partnership issues between the British Journal of Sports Medicine and the IOC. Screening for silent but potentially deadly heart abnormalities in athletes before they embark on a career in competitive sports, known as preparticipation cardiovascular screening, has been the subject of considerable debate, according to the authors. The researchers applied the Lausanne recommendations to 371 athletes between the ages of 12 and 25 over a period of two years. The recommendations published in 2005 in Europe advocate taking a personal and medical history, a physical examination, and an ECG for every young competitive athlete. The results showed that ECG produced false positive results for 47 athletes (11%), which is an acceptable rate, and picked up problems in a further 10 (2%), of whom four were restricted from further participation in sport. The number of screens needed to pick up one athlete with potentially lethal cardiovascular disease was 143, which is well within acceptable limits for any screening program, according to the authors. In another review of the available evidence, British researchers confirm that trying to pick up potentially fatal heart abnormalities through questionnaires and physical exam alone is not very effective.
— Compiled by Amanda Pedersen, MDD