Clinical Applications

Each year, more than 5 million patients undergo perfusion testing in the United States. The main reason for these studies is to detect and evaluate ischemic heart disease and myocardial infarction.1 (Data on file, AMR)

Ischemic Heart Disease. A perfusion stress test might be performed in a patient with atypical chest pain, an abnormal ECG, severe coronary risk factors, and a previous nondiagnostic standard ECG stress test.1 (Berman 1995/p 30)

The data about the extent of ischemic heart disease gained from a perfusion study can aid in:

• Determining prognosis2-4 (Shaw 2000) (Shaw 2003) (Schinkel)
• Choosing therapy options5,6 (Palta/p310) (Berman 1996/pS42)
• Screening high-risk patients before noncardiac surgery1,5 (Berman 1995/p3D) (Palta/p310)
• Evaluating therapy efficacy1 (Berman 1995/p3D)
• Screening high-risk CD candidates1,6 (Berman 1995/p3D) (Berman 1996)

Patients who show transient ischemia on perfusion studies have a high risk of future cardiac events as do patients who show fixed defects. On the other hand, normal perfusion stress images in patients with documented CAD indicate a favorable prognosis.2-4 (Shaw 2000/p2,3,6) (Shaw 2003/p6) (Schinkel/p410,411)

By illustrating the extent of the defects, perfusion studies can also help determine the optimal therapy for a patient. For instance, severe scan abnormalities may indicate that a patient requires cardiac catheterization and subsequent bypass surgery, whereas less severe perfusion defects may indicate that the patient can be managed with a medical regimen.2-4 (Shaw 2000/p6) (Shaw 2003/p1,4-6) (Schinkel/p411)

Myocardial Infarction. Perfusion studies can refine the detection and treatment options between cardiac death and acute myocardial infarction (MI). Early studies with myocardial perfusion SPECT grouped cardiac death and MI together in defining hard events. However, because treatment strategies differ for prevention of MI and cardiac death, taking full advantage of prognostic testing should differentiate these two endpoints, as well as patient management.6 (Berman 1996 pS46-S49)

Perfusion studies are routinely performed in patients hospitalized with an acute MI in order to evaluate exercise capacity and the extent of ischemia before they leave the hospital. Information from the study is used for cardiac rehabilitation and to identify those patients at high risk for future cardiac events.4 (Schinkel/p410-411)

References: 1. Berman D, Kiat H, Friedman J, Diamond G. Clinical applications of exercise nuclear cardiology studies in the era of healthcare reform. Am J Cardiol. 1995;75:3D-13D. 2. Shaw LJ, Hachamovitch R, Heller GV, et al, for the Economics of Noninvasive Diagnosis (END) Study Group. Noninvasive strategies for the estimation of cardiac risk in stable chest pain patients. Am J Cardiol. 2000;86:1-7. 3. Shaw LJ, Hendel R, Borges-Neto S, et al, for the Myoview Multicenter Registry. Prognostic value of normal exercise and adenosine 99mTc-tetrofosmin SPECT imaging: results from the multicenter registry of 4,728 patients. J Nucl Med. 2003;44:134-139. 4. Schinkel AF, Elhendy A, van Domburg RT, et al. Incremental value of exercise technetium-99m tetrofosmin myocardial perfusion single-photon emission computed tomography for the prediction of cardiac events. Am J Cardiol 2003;91:408- 411. 5. Palda VA, Detsky AS. Guidelines for assessing and managing the perioperative risk from coronary artery disease associated with major noncardiac surgery. Ann Intern Med. 1997;127:309-312. 6. Berman DS, Hachamovitch R. Risk assessment in patients with stable coronary artery disease: incremental value of nuclear imaging. J Nucl Cardiol. 1996;3:S41-S49.