Cardiovascular - August 2012 Archives

ROCHESTER, Minn. — August 27, 2012.  People who are of normal weight but have fat concentrated in their bellies have a higher death risk than those who are obese, according to Mayo Clinic research presented today at the European Society of Cardiology Congress in Munich. Those studied who had a normal body mass index but central obesity — a high waist-to-hip ratio — had the highest cardiovascular death risk and the highest death risk from all causes, the analysis found. "We knew from previous research that central obesity is bad, but what is new in this research is that the distribution of the fat is very important even in people with a normal weight," says senior author Francisco Lopez-Jimenez, M.D., a cardiologist at Mayo Clinic in Rochester. "This group has the highest death rate, even higher than those who are considered obese based on body mass index. From a public health perspective, this is a significant finding." The study included 12,785 people 18 and older from the Third National Health and Nutrition Examination Survey, a representative sample of the U.S. population. The survey recorded body measurements such as height, weight, waist circumference and hip circumference, as well as socioeconomic status, comorbidities, and physiological and laboratory measurements. Baseline data were matched to the National Death Index to assess deaths at follow-up. Those studied were divided by body mass index into three categories (normal: 18.5–24.9 kg/m2; overweight: 25.0–29.9 kg/m2; and obese: >30 kg/m2) and two categories of waist-to-hip ratio (normal: The mean age was 44; 47.4 percent were men. The median follow-up period was 14.3 years. There were 2,562 deaths, of which 1,138 were cardiovascular related. The risk of cardiovascular death was 2.75 times higher, and the risk of death from all causes was 2.08 times higher, in people of normal weight with central obesity, compared with those with a normal body mass index and waist-to-hip ratio. "The high risk of death may be related to a higher visceral fat accumulation in this group, which is associated with insulin resistance and other risk factors, the limited amount of fat located on the hips and legs, which is fat with presumed protective effects, and to the relatively limited amount of muscle mass," says Karine Sahakyan, M.D., Ph.D., a cardiovascular research fellow at Mayo Clinic in Rochester.

People who are of normal weight but have fat concentrated in their bellies have a higher death risk than those who are obese. The Mayo Clinic ...

In the U.S., hundreds of thousands of X-rays are performed each year to detect and treat common cardiovascular conditions. But there's growing concern about the potential risks of ...

ROCHESTER, Minn. — August 16, 2012.  Each year, hundreds of thousands of X-rays are performed across the country to help detect and treat common cardiovascular conditions such as coronary artery disease, valve disease and other heart problems. However, concern is growing within the medical community about the potential risks of radiation exposure from this imaging technology. Now, researchers at Mayo Clinic have been able to dramatically cut the amount of radiation that patients and medical personnel are exposed to during invasive cardiovascular procedures. The solution: targeted modifications to the use of standard X-ray equipment, coupled with intensive radiation safety training. The efforts are detailed in a paper published online Aug. 20 in the Journal of the American College of Cardiology: Cardiovascular Interventions. MULTIMEDIA ALERT: Video of Dr. Ken Fetterly is available for journalists to download on the Mayo Clinic News Network "Through our efforts, we were able to quickly cut the overall radiation exposure to patients by nearly half using simple but effective methods," said Charanjit Rihal, M.D., chair of Mayo's Division of Cardiovascular Diseases. "We think this program could serve as a useful model for other cath labs in the U.S." Cardiologists rely on X-ray images to identify heart problems and provide real-time guidance for procedures such as implanting stents to open narrowed arteries and aortic valve replacement. However, radiation from X-rays can be harmful. It can injure the skin if not administered judiciously, and can also damage DNA, which can increase the risk of certain cancers. The amount of radiation used in a procedure should not exceed the minimum necessary, Dr. Rihal says. Recognizing this, Mayo instituted a broad-based program that has raised awareness about radiation safety and changed the way standard X-ray systems are used in the cath lab. For example, medical staff now set the radiation output of their systems to a very low setting, minimizing the radiation dose to their patients. They only increase the radiation dose if higher-quality images are needed, such as temporarily during a critical portion of a procedure. As a result, they can obtain useful images while lowering radiation exposure. In addition, practice-wide radiation safety is now included when training fellows and junior faculty. The cath lab teams also are informed of the radiation dose delivered to patients during each procedure. Radiation exposure is routinely reported in the patient's medical record. "The reductions in the radiation dose administered to patients occurred practice-wide and across diverse procedures," says Kenneth Fetterly, Ph.D., Division of Cardiovascular Diseases. Dr. Fetterly says the initiative is part of Mayo's ongoing commitment to patient safety. The changes implemented by Mayo go well beyond standard procedures used in hospitals across the country. Buy-in across the practice is needed for such programs to succeed, Dr. Fetterly says. Success also requires physicians to shift their expectations from attaining the highest image quality to focusing on lower radiation exposure and accepting adequate image quality.