Circ: Cards use of noninvasive imaging fuels Medicare growth

The services and allowed charges by cardiologists for treating Medicare patients increased dramatically between 1999 and 2008, according to an analysis published online Jan. 10 in Circulation: Cardiovascular Quality and Outcomes. Much of the growth was linked to noninvasive imaging, with resting echocardiograms and nuclear stress testing fueling the lion’s share of growth.

Bruce W. Andrus, MD, and H. Gilbert Welch, MD, MPH, both of the Dartmouth Institute for Health Care Policy and Clinical Practice at Dartmouth Medical School in Hanover, N.H., used fee-for-service Medicare Part B claims from 1999 to 2008 for their analysis. They grouped the roughly 1,000 CPT-9 codes submitted by cardiologists into 45 service categories and then assigned them to one of three types: evaluation and management, noninvasive procedures and invasive procedures.

They calculated utilization rates for each of the 45 categories and determined changes in volume using 1999 as a base year. Their primary outcome measures were services and allowed charges per 1,000 beneficiaries.

They found that cardiologists’ claims increased 44 percent between 1999 and 2008, and allowed charges rose 28 percent after adjusting for inflation. Noninvasive procedures gobbled up most of the growth, accounting for 78 percent of the total increase in services. Invasive procedures accounted for a modest 5 percent and evaluation and management totaled 17 percent.

When Andrus and Welch examined components within noninvasive procedures, they traced much of the rise to echocardiography and nuclear stress testing. They found that the rate of transthoracic echocardiography had nearly doubled while stress tests with nuclear imaging had tripled over the decade. Echocardiography and nuclear stress testing took up 32 percent and 16 percent, respectively, of total growth in services and 18 percent and 27 percent, respectively, of the total growth in charges.

“Increasing utilization of nuclear stress testing and echocardiography strains the sustainability of Medicare and drives declining reimbursement for these studies,” they wrote. “Increasing expenditures, more broadly, hinder efforts to maintain current benefits, consider new services or expand access to healthcare.”

They speculated on reasons for the uptick in noninvasive imaging: patient preference, lack of confidence in physical examinations, new indications for defibrillators and cardiac resynchronization therapy, a desire to monitor patients more closely, efforts to avoid litigation and more mid-level practitioners involved in care. They also added that utilization may be tied to efforts to compensate for losses from declining revenue in other areas of a cardiology practice.

Study limitations included the fact that within the 10-year period under study, designations in Medicare trended away from multispecialties, which could have led to some misattributions in the study. The data did not include charges for the technical component of services, which may have led to underestimation of the growth in spending, they wrote.

Andrus and Welch praised the use of appropriate use criteria and integration of evidence-based recommendations into EMR systems. They highlighted the approach as preferable to across-the-board cuts in reimbursements. “[W]e are concerned that increased expenditures on imaging puts undesirable downward pressure on reimbursement for bedside evaluation and management services—a careful history and examination, explaining the assessment and reviewing options—services that we believe are underrepresented,” they concluded.