Keeping you up to date on recent headlines in cardiovascular healthcare:
Chest pain CT Scans validated by long-term study .... Research from the University of Pennsylvania School of Medicine (Philadelphia), presented May 15 at the annual conference of the Society for Academic Emergency Medicine (Lansing, Michigan) confirms that screening with coronary computerized tomographic angiography (CTA) is a safe/effective way to rule out serious heart disease in patients presenting with chest pain. Among 481 patients in the trial, after getting a negative scan no evidence of dangerous blockages in the coronary arteries – none had heart attacks or required bypass surgery or placement of stents in one-year follow-up. The authors say the findings provide a roadmap for appropriately and cost-effectively using this technology, which generates 3D images of the heart and the blood vessels surrounding it. The researchers used the trial to argue for "a national coverage decision that will facilitate coronary CTA in the emergency department."
Stem cell transplant in mouse embryo yields heart protection .... A study by researchers at Mayo Clinic (Rochester, Minnesota) describes how embryonic stem cells delivered to mouse embryos, in the earliest stages of development, resulted in the mice being able to recover from cardiac injury in adulthood. Mice that received embryonic stem cell treatment recovered cardiac function, while a control group deteriorated, demonstrating ischemic myopathy, myocardial scarring and significant pulmonary congestion, typical in progression towards heart failure. "Preemptive stem cell-based intervention in utero thus provides a strategy to engineer tolerance, and prevent incidence of life-threatening organ failure in the adult," the authors say, calling this the first evidence that regenerative medicine may be useful in treating myocardial infarction through prophylactic intervention. The study is published in Stem Cells.
Low, high levels of hormone in men with HF increases death risk .... Men with systolic chronic heart failure (HF) who have low or high levels of estradiol, a form of estrogen, have an increased risk of death compared with men with only moderate levels. Researchers at the Center for Heart Disease, Military Hospital (Wroclaw, Poland) examined the relationship between estradiol in the blood and the death in men with HF and reduced left ventricular ejection fraction. The study included 501 men divided into five groups, determined by the level of estradiol in their blood. Lowest mortality was in patients with estradiol levels within the middle quintile; the highest three-year mortality rate was in men in the lowest quintile (about four times higher risk of death) and those in the highest quintile (twice the risk of death) of circulating estradiol levels. The study appears in the May 13 issue of JAMA (301:1892-1901).
Selected reports from the 30th Annual Scientific Sessions of the Heart Rhythm Society (HRS; Washington) May 13-16 in Boston:
• Study: ICDs extend heart attack survivors lives by a year .... A follow-up study has found that heart attack survivors who receive implanted cardioverter defribillators (ICDs) live longer the longer they have them, according to the results of late-breaking clinical trail presented at HRS 2009. The study followed for eight years the patients of the 2002 MADIT II trial, finding that patients with ICDs had a 37% lower chance of death from any cause than those without one, translating into 1.2 life-years saved. Ilan Goldenberg, MD, research associate professor within the Heart Research Follow-up Program at the University of Rochester Medical Center (Rochester, New York), said that the results "emphasize the life-saving value of ICDs as chronic therapy for high-risk cardiac patients."
• Expert consensus on catheter ablation of arrhythmias issued .... A call for more research concerning the catheter ablation of ventricular arrhythmias (VA) was issued at the scientific sessions via a joint document from the European Heart Rhythm Association, a branch of the European Society of Cardiology (Sophia Antipolis, France) and the HRS. The document updates a review of indications, techniques and outcomes of catheter ablation for treatment of ventricular arrhythmias, a technique now being offered to increasing numbers of patients. It was written by 20 European and U.S. electrophysiologists and says that there is still "very limited" data establishing the long-term impact of catheter ablation on morbidity and mortality. Questions highlighted by the joint document include: the long term efficacy of catheter ablation, the comparative success rates of drug and ablative therapies, and whether ablation slows the progression of ventricular remodeling in structural heart disease?
• Study shows relationship between AF, development of Alzheimer's .... Researchers at Intermountain Medical Center (Salt Lake City, Utah) reported a potential connection between AF and Alzheimer's disease. Researchers studied more than 37,000 individuals, using data from the Intermountain Heart Collaborative Study, and found that those with AF 44% more likely to develop dementia than those without AF. Those with AF under age 70 were 130% more likely to develop Alzheimer's. And those with both AF and dementia were 61% more likely to die during the study period than dementia patients without AF. T. Jared Bunch, MD, said that this was the first "large-population" study to demonstrate what has been long suspected. "The Alzheimer's findings – particularly the risk of death for younger patients – break new ground."
• Medtronic completes enrollment in TTOP-AF trial .... Medtronic (Minneapolis) utilized the HRS conference to report completing enrollment in the Tailored Treatment of Permanent Atrial Fibrillation (TTOP-AF) trial evaluating the use of its latest radio frequency (RF) ablation technology. The Ablation Frontiers Cardiac Ablation System, for the treatment of continuous AF is comprised of a RF generator and three anatomically shaped mapping and ablation catheters that target three areas of the heart for AF treatment. The system is approved for use in Europe but not in the U.S. Enrollment completion follows Medtronic's recent acquisitions of Ablation Frontiers (Carlsbad, California) and CryoCath Technologies (Montreal) to form Medtronic's AF Solutions division (Medical Device Daily, Feb. 9, 2009/Dec. 22, 2008), saying it will offer a complete line of diagnostic, cryoablation and RF tools to treat AF.
• Study: ablation superior to drugs for treating AF .... One year after undergoing catheter ablation, 63% of patients with AF were free of any recurrent atrial arrhythmias or symptoms, vs. 7% of those treated according to an international study; 17% of those treated with drugs were arrhythmia-free. The ablation group also scored significantly higher on a quality-of-life scale. Based on the results, the trial was halted early. The study included 167 patients at 19 centers, including 15 centers in the U.S., and the researchers said it is the largest to date to compare ablation to drug therapy for AF. The research was funded by Biosense Webster (Diamond Bar, California), which makes the ThermoCool catheter system used in the study. An additional study called CABANA is designed to determine whether ablation patients live longer than patients receiving medication. Researchers will follow about 3,000 patients for three years.
— Compiled by Don Long, MDD National Editor