Doctors said the simple technique, which already is being used with some dramatic results at two Milwaukee hospitals, could revolutionize the acute treatment of congestive heart failure, a condition that leads to more than 1 million hospital admissions per year in the United States and costs the heath care system $28 billion annually.
Beyond that, there is hope that larger trials will show that the technique may improve survival for a condition that has a high mortality rate.
The clinical trial of the new blood filtration system, which compared the system with conventional intravenous diuretics in 200 patients, was presented Sunday at the American College of Cardiology's annual scientific sessions in Atlanta.
In patients with heart failure, the lungs and other organs can fill with fluid as a result of the heart's inability to pump adequate blood out to the body. Feet, legs, the heart and other areas can become swollen. Eventually, the situation can worsen so that patients can't breathe or walk and their kidneys fail, requiring hospitalization for treatment with IV diuretics.
More than 5 million people in the U.S. have heart failure.
Using a filtration device made by CHF Solutions of Brooklyn Park, Minn., doctors were able to remove up to a pint - about one pound - of water and sodium an hour.
Device already used locally
Since December, doctors at Froedtert Memorial Lutheran Hospital have treated about 10 patients, some with amazing results, said Mary Ann Papp, director of the hospital's heart failure clinic and an associate professor of cardiology at the Medical College of Wisconsin.
A man from Green Bay was hospitalized in early February with extensive fluid buildup, and the device drained off 27 pounds of water and sodium, she said. In the last five weeks, he has not gained back one pound of that the fluid, she said.
About the same time, a man from Ozaukee County had about 15 pounds of fluid filtered, she said.
"There is substantial improvement in the quality of life," Papp said. "For anybody who carries around 30 pounds of fluid . . . this is a blessing. Two years ago, I thought this was a gimmick. This is a real gift."
Doctors at Froedtert and St. Luke's Medical Center both were part of the clinical trial. St. Luke's has used the device on five patients.
"It works pretty quickly," said Barbara Pisani, a transplant cardiologist at St. Luke's.
Pisani said one of the big problems with conventional diuretics is that patients can become resistant to them. In addition, over time diuretics can become harmful to the kidneys, she said.
"I think it (filtration) probably will be very beneficial," she said.
Filtration has advantages
Compared with intravenous diuretics, filtration resulted in 28% more fluid loss and 38% more weight loss after 48 hours of treatment, according to the study.
Ninety days after treatment, there were 50% fewer hospitalizations in the filtration patients, 52% fewer visits to the emergency room and a 63% reduction in days of subsequent hospitalization.
Heart failure is the most common cause of hospitalization in the U.S., said lead author Maria Rosa Costanzo, a cardiologist and heart failure specialist with Midwest Heart Specialists of Naperville, Ill. Costanzo also is a consultant to CHS Solutions and owns stock in the company, which funded the study.
More than 90% of those admissions are caused by the buildup of water and salt in organs, Costanzo said.
Up until now, she said, diuretics have been the unchallenged preferred treatment. However, with repeated use those drugs become ineffective.
In fact, over the long term, the drugs are associated with a worsening of heart failure, she said.
That's because they can initiate a physiological response involving the kidneys that, ultimately, leads to the heart becoming larger and less efficient in its pumping as well as causing constriction of blood vessels in other organs, she said.
"It (IV diuretics) is the main factor that causes the progression of heart failure," she said.
Costanzo noted that there were two fewer deaths among the filtration patients in the study (9 vs. 11), although the trial was not large enough for that finding to be statistically significant. Costanzo said she believes a larger clinical trial will show improved survival with filtration.
The system works by placing a catheter in a vein in an arm or the neck and running the blood through a special filter before returning it through another vein after it has been filtered. The machine costs about $10,000. Each filter costs $800. |
