Cutting angioplasty risks

Feb 16 2006

Significant gains made through multi-hospital cooperative effort led by U-M Cardiovascular Center and funded by Blue Cross Blue Shield of Michigan.

Each year, more than 600,000 Americans have angioplasty procedures to open clogged arteries near their hearts, and treat or prevent a heart attack. But a new study shows that the quality and risk of their treatment can vary widely depending on where they go - and demonstrates how it could be improved.

In a paper published in the journal Circulation, a group of Michigan researchers reports data from a multi-hospital project that studied angioplasty care and outcomes at five hospitals where doctors and nurses received guidance and data to help them improve angioplasty care, and seven hospitals where they did not.

The project is led by researchers from the University of Michigan Cardiovascular Center and was initially funded by the Blue Cross Blue Shield of Michigan Foundation, with ongoing funding from Blue Cross Blue Shield of Michigan and Blue Care Network. It's called the Blue Cross Blue Shield of Michigan Cardiovascular Consortium, or BMC2.

The results yielded a dramatic "before" and "after" contrast. Before the start of the project, the 3,731 patients treated at the five hospitals in one year received widely varying levels of care. Many never received drugs that could help prevent complications during or after their angioplasty, while others received far more than necessary of the blood-thinning drug heparin, or the dye that lets doctors see blockages while they perform the minimally invasive procedure.

There was also wide variation in how patients did afterward, including their risk of kidney damage related to the dye, and their need for emergency heart surgery and blood transfusions.

But five years later, after the intensive quality-improvement project was under way, the 5,901 patients treated at the same five hospitals in that year received much better and more uniform care, including much higher rates of preventive medication use, less use of heparin, and more appropriate amounts of dye. They also did better overall, with lower rates of complications related to their hearts and kidneys.

At the seven comparison hospitals, the researchers looked at data from 10,287 patients who had angioplasties during 2002, the same year as the "after" measurements at the five hospitals. They found wide variation in the use of preventive medications, heparin and dye, and higher rates of some complications than at the five other hospitals. All seven hospitals in the comparison group are now part of the quality-improvement project.

"The technology used in these procedures has reached such a point that patients' outcomes today depend more on practice variations than on limitations of technology," says Mauro Moscucci, M.D., the U-M cardiologist who leads the project with BCBSM's David Share, M.D., MPH. "It is crucial that we understand how individual physicians and hospitals vary, and work to reduce that variation so that each patient's care is delivered in a way that reduces risks and complications, and gives patients the best chance at a good outcome," he explains.

Adds Share, "The BMC2 project has provided physicians the resources they need to rigorously examine angioplasty practice, to better define optimal care, and to use what is learned to improve patient outcomes. It has been exceptionally gratifying to witness the high level of trust evidenced by otherwise competing physicians and hospitals as they work to raise the bar of quality for all patients undergoing angioplasty. The decreases in mortality and complications of care are a tremendous reward for the hard work of all involved."

Moscucci, who is director of Interventional Cardiology for the U-M CVC, notes that many factors are at the heart of the variation in angioplasty and other procedures known as percutaneous coronary interventions, and that it takes a focused effort to overcome them.

For example, a lack of time or up-to-the-minute knowledge on the part of an individual doctor may mean that he or she doesn't always make sure that patients scheduled for an angioplasty receive aspirin before their procedure, even though aspirin has been shown to reduce complications during and after angioplasty. Individual doctors may not realize how much their care differs from their colleagues at the same hospital, much less another hospital.

The BMC2 project helped hospitals and doctors understand just how they were doing on delivering key medications or reducing risks - and to adopt practices that would help them improve.

For instance, the project's participants developed quick-reference tools that could be used to calculate how much dye was appropriate for each patient, or what their risk of suffering complications might be - thereby allowing doctors and nurses to customize the treatment before, during and after that patient's angioplasty.

Each doctor and hospital in the study also received quarterly reports about how they measured up against the others in the project, on many different measures of preventive care, risk-reducing steps and outcomes. Regular meetings of participating clinicians, and visits by Moscucci and his team, helped all participants share results and plan new improvements. Each hospital team looked at their institution's own procedures and protocols and found new ways to make sure that patients didn't miss out on important medicines or face unnecessary risks.

While the data reported in the Circulation paper cannot show cause and effect because the hospitals were not randomized to the intervention or control groups, Moscucci and Share note that the association between the quality improvement project and the improvement in patient outcomes is strong. The effect was still statistically significant even after the data had been adjusted for patients' individual risk factors.

The project is especially relevant, they say, in light of the growing trend toward "pay for performance" incentives from insurers, and public reporting of quality measures for individual doctors and hospitals, including the number of angioplasties performed each year and patient-complication and survival rates. Moscucci and his colleagues from U-M, BCBSM and other institutions have recently reported data on how such factors influence the quality of care.

Meanwhile, the BMC2 project continues to grow. Seventeen Michigan hospitals now participate and continue to make improvements and share data. BCBSM now requires membership in the consortium for any hospital that wants to be listed as one of its Cardiac Centers of Excellence. Blue Cross Blue Shield of Michigan and Blue Care Network are independent licensees of the Blue Cross and Blue Shield Association.