Turning to SPECT/CT for Calcium Scoring to Diagnose Coronary Artery Disease
Source: Medical University of South Carolina, Charleston. | |
MII: What is the rationale for SPECT/CT plus calcium scoring? Are there downsides to traditional nuclear stress testing?
Milbourne: Traditional nuclear testing with thallium or technetium can produce equivocal results. If a patient is asymptomatic or presents with unknown risk factors, a nuclear stress test alone can show normal perfusion and fail to detect ischemia. Many patients with significant CAD show normal perfusion via conventional testing. A Symbia T2 [study] with calcium score, on the other hand, shows not only any ischemia present, but also asseses the buildup of calcium in the coronary arteries.
With 20 percent of heart attacks occurring in patients with no risk factors, it is critical to definitively screen for and detect CAD.
MII: Can you provide some examples to illustrate how SPECT/CT with calcium scoring benefits patients?
Milbourne: I’ve seen a number of patients where Symbia T2 provided critical clinical information. Take for example a 45-year-old man with hypertension, moderate family risk factors and mildly elevated blood glucose. His EKG showed repolarization and his SPECT perfusion test was normal. The Symbia T2 calcium score of 600 showed a different picture and a much more accurate diagnosis. The patient did have underlying CAD, pointing to need for daily aspirin therapy and cholesterol-lowering lifestyle changes or medication. Another example is a recently married 26-year-old male with a strong family history of early arterial sclerosis. At the time of the calcium score, the patient was not hypertensive and had normal cholesterol. In addition, a traditional nuclear stress test showed normal perfusion. His calcium score of 170 indicated focal disease and underlying early CAD, providing the information needed to initiate a strong early preventative program.
MII: Using Symbia T2 for calcium scoring does represent an additional test. How does it impact workflow?
Milbourne: The workflow impact is negligible. The normal protocol consists of a regular nuclear stress test. The calcium score model also begins with a nuclear study and adds a 30-second CT for the calcium score.
MII: What infrastructure is needed to offer SPECT/CT for calcium scoring?
Milbourne: It is a simple program. The essential equipment is the Symbia T2 SPECT•CT camera. Siemens software that is part of their SPECT•CT Cardiology engine, delivers the calcium scoring quantification.
MII: Can you explain your practice model? How are patients referred? How has SPECT/CT calcium scoring impacted the bottom line?
Milbourne: Patients are referred from multiple avenues. Calcium scoring is straightforward and quick. Consequently, New Life Cardiovascular does not charge many patients for calcium scoring. The practice uses this model because it is better for the patient and facilitates early treatment.
Symbia T2 calcium scoring is improving the practice. It provides a great advantage over our competitors. We complete more tests because we offer better tests and clearer results.
MII: This is clearly a new model for cardiac care. Are there barriers to implementing SPECT/CT for calcium scoring?
Milbourne: The primary challenge is education. It takes a fair amount of time and effort to educate referring physicians to help them understand that screening for CAD is possible.
Insurers represent another barrier if physicians allow them to dictate how they practice medicine. The clash between the clinical and economic environments is minimized with Symbia T2 calcium scoring because the calcium score can be completed in conjunction with the nuclear test, and the additional time it takes to perform and interpret the scan is insignificant.
MII: Can you offer any predictions about the future penetration of SPECT/CT scanning and calcium scoring?
Milbourne: The paradigm is changing. We will see more patients because SPECT/CT calcium scoring is a better test than traditional nuclear stress testing, and it enables earlier diagnosis. Symbia T2 represents a quantum leap forward in our ability to see and treat coronary artery disease.