Effectiveness of nuclear scan strategy in low-risk chest pain patients

AIM: The aim this study is to update the diagnostic implementation of a costly scan strategy in chest pain (CP) patients. METHODS: Low-risk CP patients with a negative first-line work-up including clinical evaluation, serial ECGs, and serial troponins underwent stress myocardial perfusion imaging (MPI). Those with perfusion defects underwent angiography, whereas the remaining patients were discharged and followed up. The endpoint was coronary stenosis greater than or equal to 50% at angiography or cardiovascular death, myocardial infarction, unstable angina, and revascularization at follow-up. RESULTS: Out of 1089 patients enrolled, 966 underwent exercise-MPI and 123 pharmacological-MPI (91 adenosine-MPI and 32 dipyridamole-MPI). Areas under the receiver-operating characteristic curve of exercise-MPI and pharmacological-MPI were comparable. The sensitivity and negative predictive value were significantly higher in patients subjected to exercise-MPI or pharmacological-MPI versus exercise-ECG or pharmacological-ECG (P < 0.001). The presence of basal nonischemic ECG or basal nonischemic echocardiography alterations was an independent predictor of coronary events; in these patients, the positive predictive value of the nuclear scan was significantly higher compared with the remaining patients (72 vs. 43%, P < 0.0001). The predictive values in patients subjected to adenosine-MPI or dipyridamole-MPI were eventually comparable. CONCLUSION: In low-risk CP patients, a costly stress nuclear scan strategy added incremental prognostic value over stress-ECG and was appropriate especially in patients presenting basal nonischemic ECG or basal nonischemic echocardiography alterations.