The physicians who receive the most in Medicare payments are often surgeons who perform possibly unnecessary procedures in an outpatient setting. The 2012 billing data, released in April 2014, reveals that ophthalmologists, oncologists, and pathologists typically receive the highest Medicare reimbursements. However, Asad U. Qamar, MD, cardiologist at the Institute for Cardiovascular Excellence PLLC in Ocala, Florida, is among the highest billers, as a result of performing procedures to treat peripheral vascular disease (PVD). In fact, the data shows that 8 of the top 10 top-billing cardiologists in the U.S. received about half of their Medicare reimbursements from performing PVD procedures.

As the number of procedures for opening blockages in the heart fell by 30 percent from 2005 to 2013, the number of PVD procedures increased by 70 percent, according to the Advisory Board Company. While further research is needed to determine the appropriate treatment for PVD, many medical experts argue that PVD can be more safely treated with exercise and medication. However, doctors who perform PVD procedures say they reduce the number of more serious conditions, including leg amputations.

In 2012, Dr. Qamar received $18 million from Medicare—$13 million of which came from PVD procedures performed mainly in the legs. In January, the Justice Department joined two whistle-blower lawsuits against Dr. Qamar and his medical group in which he was accused of performing unnecessary operations. While only a small amount of patients require surgical procedures, from 2010 to 2011 nearly all of his patients scanned for PVD received surgical interventions, an amount “statistically impossible to medically support,” according to the lawsuit. In one instance, a female patient with blockages in her heart died of complications from a stent procedure in her legs before her heart blockage could be treated, the lawsuit contends.

Dr. Qamar denies accusations that he performed unnecessary procedures, emphasizing his clinic had the lowest amputation rates for peripheral disease in the U.S.

“Just looking at the sheer volume of work and billings from a single physician is not a sign of wrongdoing,” he said in an article in The New York Times.

He explained that PVD procedures are normally performed in a hospital in many other states. Therefore, his medical practice, which has a caseload of 23,000 patients and handles PVD procedures, had large payments.