A heart-monitoring procedure used a million or more times a year in this country to treat critically ill patients may actually be killing some of them, researchers say.
Patients who underwent the procedure, called right heart catheterization, had a 21 percent higher risk of death in the next 30 days, according to figures on 5,735 intensive-care unit patients at five U.S. medical centers.
Right heart catheterization involves inserting a balloon-tipped catheter into a neck vein and guiding it into the heart’s right atrium. The procedure allows doctors to measure how the heart is performing and choose the right treatment.
The procedure, in use for 25 years, is a central element of care for critically ill patients who are in shock or whose hearts are functioning abnormally. The annual cost associated with its use is more than $2 billion.
Though some patients might benefit from the procedure, Dr. Alfred F. Connors Jr. of the University of Virginia said his study failed to identify any who did.
“What we determined is that there clearly is an association between the use of right heart catheters and a higher rate of death,” Connors said.
Connors offered some possible reasons why: Any time a foreign agent like a catheter is inserted into the body, there’s an infection risk. And the procedure has been known to irritate the heart muscles and sometimes cause irregular heartbeats that could be fatal.
Besides the higher death rate, his study linked the procedure to longer stays in the intensive-care unit and higher hospital costs.
Connors and his colleagues said the research is the largest, most detailed study on right heart catheterization. It was published in today’s Journal of the American Medical Association.
“There’s no question that the health establishment should pay attention to that,” said Dr. Claude Lenfant, director of the National Heart, Lung and Blood Institute at the National Institutes of Health. But he said banning the procedure in the absence of further research is “perhaps a little bit jumping to conclusions.”
In an accompanying JAMA editorial, two doctors said the findings are alarming enough to warrant either immediate clinical trials by the institute or a government moratorium on the procedure.
In the study, researchers compared patients who received right-heart catheters with patients of similar age and illness who did not. Thirty-eight percent of the 5,735 patients studied received the catheters.
Of the 2,179 catheterized patients, 1,354 were still alive 30 days later, compared with 2,463 of the 3,556 who didn’t have the procedure.
The Society of Critical Care Medicine, a 9,000-member group of doctors, nurses and others involved in such care, called the study inconclusive.
“Right heart catheterization is a safe and effective diagnostic procedure for many patients,” said Dr. John W. Hoyt, the society’s president. But he said his group will immediately help launch another study.