CHICAGO People on Medicare who get elective surgery to open blocked heart arteries often do not get the recommended stress tests to confirm the surgery is warranted, U.S. researchers said on Tuesday.
The surgery, known as PCI or percutaneous coronary intervention, involves threading a balloon-tipped catheter through the arteries and opening up a clog. A tiny wire-mesh coil called a stent is often inserted to prop open the artery.
PCI costs Medicare, the U.S. government's health insurance program for people age 65 and older, $10,000 to $15,000 per procedure and has contributed significantly to increases in Medicare spending since the mid-1990s.
"It's important to document that patients are receiving PCI for appropriate indications to ensure the optimal use of Medicare resources," said Dr. Grace Lin of the University of California, San Francisco, whose study appears in the Journal of the American Medical Association.
More than 800,000 PCI procedures are performed each year and they represent big business for medical device makers including Boston Scientific Corp, Medtronic Inc, Abbott Laboratories Inc and Johnson & Johnson.
A number of prior studies have suggested that many stable patients with chest pain can get about the same level of relief with standard drug therapy, but at far lower cost.
Lin and colleagues wanted to see if doctors who are performing PCI surgeries were following widely accepted practice guidelines that call for people to undergo a stress test to determine whether the procedure is needed.
Stress tests, which are typically done on a treadmill, can show whether a person has ischemia, or inadequate supply of blood to the heart caused by a blocked artery.
"What really matters is whether or not that blockage is affecting blood flow to the heart. That is why the stress test is important," Lin said in a telephone interview.
She and colleagues studied insurance claims in 2004 from Medicare beneficiaries.
They found that fewer than half of the patients took a stress test on a treadmill within 90 days of their elective surgery. This rate varied significantly depending on the hospital patients were referred to, with rates ranging from a low of 22.1 percent to a high of 70.6 percent.
"There was a tremendous amount of variation in the amount of stress testing that was done," Lin said.
She said older doctors and those who did a high volume of procedures tended to order fewer stress tests. Because the rates differed widely by geography, she thinks local practice patterns also played a role in the decision to do the test.
The Society for Cardiovascular Angiography and Interventions said the results warrant concern, but said stress tests are not always appropriate, including for patients who are too sick or immobile to take them.
"The guidelines are important, but they are meant to guide physicians based on the data available at the time of their development, not serve as a substitute for clinical judgment," Dr. Bonnie Weiner, the group's immediate past president, said in a statement.