THURSDAY, Feb. 3 (HealthDay News) -- Besides enabling severely
obese people to lose weight, gastric bypass surgery seems to help
their overly stressed hearts return to more normal function and
appearance, a new study suggests.
Obesity is a risk factor for many types of heart problems,
including heart failure, atrial fibrillation (an abnormal heart
rhythm) and death, explained senior study author Dr. Sheldon
Litwin, chief of cardiology at the Medical College of Georgia.
The connection between obesity and cardiovascular disease isn't
fully understood, but obese people often show signs of structural
changes to the heart, including excess heart muscle mass in the
left ventricle and enlargement of the right ventricular cavity.
Both are linked to heart failure and other problems.
For this study, published in the Feb. 8 issue of the
Journal of the American College of Cardiology, researchers followed more than 400 severely obese people with an average age of 42 who had gastric bypass surgery, which reduces stomach size. They were compared with a reference group of more than 300 severely obese individuals who did not have the weight-loss surgery.
Two years later, patients' body mass index (BMI) fell from an
average of nearly 48 (morbidly obese) to about 32. Their average
weight loss was about 100 pounds, Litwin said. (A BMI of 30 is
obese, while a BMI of 25 is considered normal weight).
Participants also had smaller waistlines, lower blood pressure
and heart rate, healthier cholesterol levels and less insulin
resistance, a precursor to diabetes, the researchers found.
Echocardiograms, or ultrasounds of the heart, also showed a
"remodeling" of their heart structure, including a reduction in the
left ventricular mass and right ventricular cavity area.
Those reductions in heart mass and volume indicate a heart
that's less stressed, isn't having to work as hard pumping blood
and has returned to a more normal shape and function, Litwin
"We know obese people get cardiovascular disease more often than non-obese people," Litwin said. "One of the questions out there is: Is it reversible if they lose weight? The answer is yes."
Bariatric surgeries have increased steadily in the United States
-- from 16,800 in 1992 to about 205,000 in 2007, according to the
American Society for Metabolic & Bariatric Surgery.
The proportion of obese people having the surgery is still
small, however. Annually, less than one-fourth of 1 percent of all
obese people get it done, said Dr. Lee Kaplan, director of the
Massachusetts General Hospital Weight Center.
That's in part because the procedure remains controversial. It's
expensive and some insurance doesn't pay for it. In addition, like
all operations, bariatric surgery is not without risk. Potential
complications, for example, include blood clots, infection,
respiratory arrest, gastrointestinal bleeding, small bowel
obstruction and death, according to the American Society for
Metabolic & Bariatric Surgery.
"Would it be better if people could lose weight by eating better and exercising more? Probably yes," Litwin said. "But in general those lifestyle changes are ineffective, particularly in people who are severely obese."
The study provides more strong evidence for the benefits of
gastric bypass surgery on not only diabetes, hypertension,
cholesterol and sleep apnea, but on the heart muscle itself, Kaplan
"There are innumerable known benefits to gastric bypass surgery on most of the 60-odd diseases associated with obesity a patient may have," Kaplan said. "The question isn't if gastric bypass works. It does work. The issue has been at what cost, both in terms of health risks and financial? This study provides evidence there are additional substantial benefits with respect to heart muscle function, and we should consider gastric bypass more often in the appropriate patients."
The next step is to follow patients beyond two years to see if
they maintain their weight loss and if they have less heart trouble
over the long term, said Litwin, who was at the University of Utah
when he did the research.
U.S. National Library of Medicine describes