A change in federal reimbursement for peripheral vascular interventions shifted the proportion of treatments away from inpatient to generally less expensive outpatient settings. But it may not have saved Medicare money, according to a study.

W. Schulyer Jones, MD, of Duke Clinical Research Institute in Durham, N.C., and colleagues looked at trends in peripheral vascular interventions before and after the Centers for Medicare & Medicaid Services increased reimbursement for procedures performed in outpatient hospitals, office-based clinic and ambulatory surgery centers. They based their analysis on a 5 percent sample of Medicare data on beneficiaries with diagnosed peripheral artery disease who had a revascularization claim between 2006 and 2011.

Of the nearly 40,000 patients in the sample, 79.4 percent had a peripheral vascular intervention. The rate of peripheral vascular interventions per 100,000 patients increased over time, from 401.4 in 2006 to 419.6 in 2011. The rates for angioplasty alone and atherectomy rose from 97.7 to 109.4 and 96.4 to 125.9, respectively, while the stenting rate dropped from 207.4 to 184.3.

The rates for interventions changed as well by setting, dropping from 209.7 per 100,000 beneficiaries in 2006 to 151.6 in 2011 in inhospital settings. Outpatient hospital interventions increased, from 184.7 to 228.5.  Office-based clinic interventions rose from six to 37.8.

The atherectomy rate jumped in outpatient hospital and office-based clinic settings, from 38.6 in 2006 to 83.7 in 2011. Jones et al calculated a twofold increase in the use of atherectomies in outpatient settings and a 50-fold spike in office-based clinics. They noted that this occurred despite any strong evidence that atherectomy was more effective than other established treatments.

The total cost for an atherectomy in an outpatient setting also increased, from $2,763 in 2006 to $8,680 in 2011. Office-based clinic interventions posted even higher costs by 2011, at $13,478. By comparison, inpatient atherectomy costs remained stable, at $11,342 in 2006 and $11,446 in 2011.

“[R]eimbursement rates likely contributed to the more frequent use of atherectomy during the study period, and this increased use likely neutralized some of the cost savings to Medicare after changes to the OPPS [outpatient prospective payment system], despite a lack of efficacy data supporting atherectomy use,” they wrote.

In an accompanying editorial, Paul Heidenreich, MD, of the VA Palo Alto Health Care System in California described physicians as the “wild card” in policy changes because their treatment decisions can influence costs. “[T]he rise in atherectomy use was likely unexpected and unintended,” he wrote.

Given the lack of data on outcomes, he recommended that Medicare call for a registry for peripheral vascular intervention technologies. “Although mandated registries are impractical for every procedure lacking in evidence, the substantial budgetary effect of PVI [peripheral vascular intervention] should make it a top priority.”

The study and editorial were published in the March 10 issue of the Journal of the American College of Cardiology.