[Utility of myocardial perfusion SPECT for evaluation of patients from Chest Pain Unit]

The Chest Pain Units (CPU) are currently the best solution to improve management of patients with acute chest pain in the Emergency Room thanks to the use of reliable ischemia diagnostic detection tests and early treatment.

To assess the value of myocardial perfusion SPECT (MPS) in the CPU in order to treat acute coronary syndromes (ACS) early and discharge patients with low risk of coronary artery disease (CAD) who can be treated as outpatients.

We studied 629 patients from January 2003 to September 2005 with acute chest pain suggestive of angina, normal cardiac enzymes and normal or non-diagnostic ECG who had been referred to Nuclear Medicine for evaluation with a stress test for ischemia: 32 p treadmill stress testing and 597 p MPS (525 p exercise-rest and 72 p pharmacologic stress test). We compared the results with catheterization and clinical follow up for a 6-months period, evaluating new coronary events.

76 % of MPS were normal and 24 % pathological. Only 1.5 % of the patients with normal MPS had CAD or coronary events in the follow-up, increasing to 35.2 % in patients with ischemia. A total of 45 catheterizations were performed, showing CAD 27 (24 with pathological MPS). A total of 2.6 % of the patients had coronary events during follow-up, 75 % of whom had pathological MPS.

The MPS improves diagnosis of ACS in the CPU, with a very low number of new coronary events at 6 months of the follow-up and permits safe discharge of these patients.