ABC | Volume 114, Nº2, February 2020

Update Update of the Brazilian Guideline on Nuclear Cardiology – 2020 Arq Bras Cardiol. 2020; 114(2):325-429 Figure 32 – Case 5 - Myocardial perfusion scintigraphy demonstrating significant ischemia in the territory of the anterior descending artery. Images acquired with dedicated cardiac equipment (gamma camera), equipped with conventional sodium iodide crystals. 6. Patient with abnormal ET, normal MPS, and normal coronary angio-CT results Clinical history: male, age 33, atypical chest pain, recent onset of DM, high blood pressure (HBP) and family history of early CAD, ET resulting in intermediate-risk Duke score (+3). Findings: The stress phase of the ET revealed high estimated metabolic expenditure (11 METs), with 9 minutes in the Ellestad protocol. ST-segment depression of up to 1.5 mm (measured in the J point), with a descending aspect (Figure 33), were observed in multiple leads, during the recovery phase only, and they were sustained until the end of this phase. The Duke score was +3 (intermediate-risk), and MPS showed homogenous radiopharmaceutical distribution throughout the walls of the LV, considered within normal limits (Figure 34). Due to persistence of symptoms during evolution, coronary angio-CT was solicited 2 months later, showing an absence of obstructive lesions and a CS of zero (Figure 35). Comments: In patients with intermediate probability of CAD, the indicated methods (MPS or angio-CT) are additional possibilities for investigation. At least 2 randomized studies have evaluated these strategies: I. The PROMISE study, 247 which included 10,003 individuals with suspected CAD, with 25 months of follow up regarding the primary outcome (composed of death, AMI, and hospitalization for UA), showed similar evolution in both randomization groups (A) functional tests, including MPS, 5,007 patients with 3% events versus B) angio-CT, 4,996 patients with 3.3% events (p = 0.75). There was, however, a higher number of revascularizations in the group that began with anatomical evaluation. II. The International Atomic Energy Agency study 248 demonstrated that the initial strategy of angio-CT entails the solicitation of additional diagnostic methods, including MPS itself or direct catheterization. These findings could have been foreseen due to the differences in information between both techniques, as coronary angio-CT is more sensitive for detection of anatomical diseases without 374