Clinical Nuclear Medicine:
In the article beginning on page 582 of the June 2014 issue, an abstract was inadvertently omitted. The Society regrets the omission. The full text of the abstract is below.
The Clinical Utility of Stress Myocardial Perfusion Imaging for Symptomatic Patients Within Three Years of a Prior Normal Study
Erica J. Cohen, D.O., M.P.H., C.C.D.
Loyola University Medical Center, Department of Nuclear Medicine, Maywood, IL
Objectives: There is a 99% negative predictive value for a major cardiac event or cardiac death over the 36 months following a normal myocardial perfusion exam. The American College of Cardiology Foundation along with key specialty and subspecialty societies recently released updated Appropriate Use Criteria for the evaluation of stable ischemic heart disease. In the setting of stable symptoms and a normal stress imaging study performed within the past 2 years, regardless of global CAD risk, repeat myocardial perfusion imaging is rarely appropriate. For those patients with a normal study performed greater than 2 years ago and with intermediate to high CAD risk, a repeat nuclear imaging exam may be appropriate. The purpose of this study was to determine the utility of performing a stress myocardial perfusion study for a clinically symptomatic patient within three years of a prior normal study, regardless of CAD risk or change in symptomatology.
Methods: Patients at Loyola University Medical Center were retrospectively reviewed between November 2011 and November 2013 for history of a prior normal stress myocardial perfusion study and a second study performed within 36 months in order to evaluate cardiac symptoms. Patients were excluded from the study if they were a recipient of a heart transplant, if testing was performed as part of a pre-operative evaluation, if patients had a history of CAD but were asymptomatic, if they did not reach at least 85% of maximum predicted heart rate during treadmill stress, if stress imaging was non-gated, or if there was any abnormal finding on their original stress exam (i.e., left ventricular dilatation, decreased ejection fraction, fixed or reversible perfusion defects, or transient ischemic dilatation). There were 206 patients who met inclusion criteria. These patients were subsequently evaluated for any new finding on their second exam, such as fixed or reversible perfusion abnormalities, left ventricular dilatation, or decreased ejection fraction. Patients who had a new finding on the second exam were further investigated in the electronic medical record to determine if there was any significant change in clinical management, such as percutaneous coronary intervention, addition of cardiac medications, or adjustment of prior cardiac medications. Four patients were excluded from the study as no information about further clinical management was available.
Results: Of 202 patients, 21 demonstrated new abnormal findings on their second examination (10%). Of those patients with new abnormal findings, 7 patients had a change in clinical management. The other 14 patients were not recommended any change in clinical management; this was based on normal findings at coronary angiography (5), a normal follow-up echocardiogram (4), or the cardiologist’s determination of only minor abnormalities on myocardial imaging (5). In total, only 7 of 202 patients (3%) had a significant change in clinical management. The average time between scanning was 20.5 months.
Conclusions: Stress myocardial perfusion imaging performed within three years of a prior normal study has low clinical utility, even in the setting of symptomatic patients. Only 3% of patients in this study had a change in clinical management as a result of a second examination. These findings generally support the recommendations of the American College of Cardiology Foundation, but do not discriminate based on CAD risk or change in symptomatology. It is therefore reasonable to conclude that rather than undergo repeat myocardial perfusion imaging, these patients may be treated by medical optimization with concurrent evaluation for other non-cardiac etiologies of their symptoms.
American College of Nuclear Medicine 2014 annual meeting and Society of Nuclear Medicine and Molecular Imaging mid-winter meeting resident and fellow abstracts Palm Springs, California: February 6–9, 2014. Clin Nucl Med 2014;39:582—591.