Jury still out on cardiac CT scans

Radiologists appear thrilled to show the latest scanners in cardiac testing, but how best to use these new $1.5 million to $2 million machines is the question.

The 64-slice computed tomography (CT) scanners produce stunning, three-dimensional color images of arteries and internal organs. First introduced in 2004,    use of the scanners is spreading steadily through hospitals and radiology practices.

The CT scans take hundreds of pictures per second and computer programs convert them into three-dimensional images and motion pictures with incredible detail.

Coronary artery CT scans carry relatively few risks and the procedure is more comfortable compared to invasive angiograms, the standard cardiac test that involves inserting a catheter into the groin and up through the aorta. They're also more    accurate at detecting moderate levels of heart disease than stress tests. However,   there are no accepted guidelines on when a cardiologist should order a coronary  artery CT scan. And insurance companies haven't embraced them.

Since 2004, Dr. Claudio Smuclovisky has read more than 3,000 coronary artery CT scans at Holy Cross Hospital in Fort Lauderdale and at his Boca Raton imaging center. He also trains doctors nationwide in the new technology.

"This is a new technology and we're still trying to determine its best use," he said.   "The beauty of this is we can see the disease before you have a heart attack."

A coronary artery CT scan shows the precise level of blockage in arteries, and it can detect other cardiac problems. Smuclovisky said he recently used the scan to  diagnose a 17-year-old who had a heart attack with a dangerous heart abnormality that an invasive angiogram couldn't find.

These CT scanners can be very useful in the emergency room, said Dr. Wayne Lee, senior medical officer with Phoenix Physicians, which staffs hospital emergency departments in South Florida. They can quickly screen patients for multiple problems to determine if they have risky conditions, such as heart disease, before they're  treated. CT scans also let doctors use only one test to check for multiple conditions besides heart disease that may cause chest pain.

That's a reason some local hospitals are acquiring these scanners and situating them close to the ER. But they are not as likely to refer patients for CT scans before they are in critical condition.

"The exact issue as to what patient requires a particular study is still being worked  out," said Dr. Joshua Purow, an invasive cardiologist who practices at North Ridge Medical Center in Fort Lauderdale. "So far, the stress test remains the most widespread procedure that we use, but eventually the CT angiogram will replace   that."

There are several types of stress tests, most involving some sort of exercise and    heart monitoring devices. While these are good indicators of people with severe    heart problems - those with at least 70 percent blockage - they aren't any good at identifying people with moderate or early stages of heart disease, Purow said.

Even someone with 50 percent blockage can have the plaque rupture, causing a    heart attack. In fact, most heart attack victims only had moderate plaque buildup because they are less likely to experience symptoms and seek treatment before a  heart attack, Purow said.

If a patient has major symptoms of heart disease, he would recommend an invasive angiogram so it can be taken care of through surgery immediately. Purow would recommend a CT angiogram for patients with intermediate risks for heart disease.

Purow's eight-doctor practice, Cardiology Associates of Fort Lauderdale, is considering buying a 64-slice CT scanner, but is first observing how the test    develops before making such a major investment.

An invasive angiogram is still considered the gold standard for detecting heart   disease, said Dr. Melvin Feltcher, VP of field professional programs in South Florida for Blue Cross Blue Shield of Florida (BCBSF). There are no studies that conclude where a coronary artery CT should be placed in the mix, he said.

"A lot of people ask: What does the CT add?" Feltcher said. "Nobody is going to operate on you or decide to do a lifelong treatment based on the result of this CT  test."

A positive coronary artery CT scan, which has a 15 percent to 20 percent false-positive rate, only invites more testing, he said. It usually leads to an invasive angiogram.

Since the American Medical Association hasn't assigned coronary artery CT scans their own billing code, insurers can't track how many are ordered, Feltcher said. Doctors usually bill them under codes for other procedures and BCBSF sometimes covers them, but won't develop a set policy until the procedure is given its own code sometime this year, he said.

Insurance companies should eventually embrace CT scans over invasive angiograms, said Dr. Philip Oranburg, medical director of ProActive, a heart health center in    Boca Raton.

Invasive angiograms carry some risk of bleeding and a small risk of causing a heart attack or stroke versus a CT scan with little radioactive risks, Oranburg said.   Because of the hospital stay and hours of bed rest, an invasive angiogram can cost about $20,000. A CT scan can be done in an outpatient center and costs between $900 and $1,000, he said.

Dr. Smuclovisky believes the CT scan will become a standard screening tool for   heart disease in much the same way a colonoscopy is used to screen for cancer. But first, more doctors need to be trained on it and studies much be done on the   economic viability of screening.

"We used to think of the coronary arteries as plumbing, where, if it's clogged, then   you fix it," Smuclovisky said. "Now, we want to know there's a problem before we have a clog so the heart attack doesn't happen."