ABC | Volume 110, Nº2, February 2018

Original Article Current Practices in Myocardial Perfusion Scintigraphy in Brazil and Adherence to the IAEA Recommendations: Results of a Cross‑Sectional Study Carlos Vitor Braga Rodrigues, 1 Anderson Oliveira, 2 Christiane Cigagna Wiefels, 1 Maurício de Souza Leão, 1 Cláudio Tinoco Mesquita 1 Setor de Medicina Nuclear - Hospital Universitário Antônio Pedro (HUAP) - Universidade Federal Fluminense (UFF), 1 Niterói, RJ; Comissão Nacional de Energia Nuclear, 2 Rio de Janeiro, RJ – Brazil Mailing Address: Carlos Vitor Braga Rodrigues • Setor de Medicina Nuclear - HUAP - Rua Marques de Paraná, 303/2º andar - Prédio Principal. Postal Code 24033-900, Centro, Niterói, RJ - Brazil E-mail: carlosvitorbr@gmail.com , legserv@bol.com.br Manuscript received March 02, 2017, revised September 27, 2017, accepted October 06, 2017 DOI: 10.5935/abc.20180023 Abstract Background: Data on the current situation of nuclear medicine practices in cardiology in Brazil are scarce. The International Atomic Energy Agency (IAEA) has recommended eight “good practices” to minimize patients’ ionizing radiation exposure during myocardial perfusion scintigraphy (MPS). Objectives: To assess the adoption of the eight good practices in MPS in Brazil. Methods: Cross-sectional study with data obtained by use of a questionnaire. All hypothesis tests performed considered a significance level of 5%. Results: We observed that 100% of the nuclear medicine services (NMS) assessed do not use thallium-201 as the preferred protocol. Regarding the use of technetium-99m, 57% of the NMS administer activities above the threshold recommended by the IAEA (36 mCi) or achieve an effective dose greater than 15 millisievert (mSv). The abbreviated stress-only myocardial perfusion imaging is not employed by 94% of the NMS; thus, only 19% count on strategies to reduce the radioactive doses. Approximately 52% of the NMS reported always performing dose adjustment for patient’s weight, while 35% administer poorly calculated doses in the one-day protocol. Conclusion: A considerable number of NMS in Brazil have not adopted at least six practices recommended by the IAEA. Despite the difficulties found in nuclear practice in some Brazilian regions, almost all obstacles observed can be overcome with no cost increase, emphasizing the importance of developing strategies for adopting “good practices” when performing MPS. (Arq Bras Cardiol. 2018; 110(2):175-180) Keywords: Nuclear Medicine / methods; Myocardial Perfusion Imaging; Myocardial Ischemia / diagnostic imaging. Introduction Myocardial perfusion scintigraphy (MPS) is a non-invasive, safe technique that uses physical or pharmacological stress to detect the presence of ischemia, assessing its early changes. The complication rate of MPS does not exceed that of exercise testing, whose mortality is estimated at 0.01%. 1 Patients with ischemia evidenced on MPS are at higher risk for adverse outcomes as compared to those with a normal test. That stratification is fundamental, because invasive approaches are only beneficial to patients at increased risk. According to the European guidelines on revascularization, the best-established techniques for diagnosing ischemia are MPS and stress echocardiography. 2 Appropriate use of invasive procedures is fundamental, because they have a high cost. The IMPACT Study has shown that most of the cost to manage coronary disease derives from invasive procedures. 3 Myocardial perfusion scintigraphy is the nuclear medicine procedure most used in Brazil, accounting for 54% of all scintigraphies performed within the Brazilian Unified Health System (SUS). 4 Although widely used, the practices are heterogeneous and can be refined, especially because they employ ionizing radiation, which, by principle of radioprotection, should be used in a justified and optimized way. Santos et al., 5 assessing the use of scintigraphy in SUS, have observed a 12% rate of inappropriate use. Those authors have reported that, with appropriate use, there will be an 18.6% reduction in budget costs, in addition to a reduction in unnecessary radiation exposure. 5 Oliveira et al., 6 however, assessing the MPS use at another institution, have found a rate of inappropriate tests of only 5.2%. 6 Considering the heterogeneous use and radiation exposure, the International Atomic Energy Agency (IAEA) recommends eight “good practices” to minimize radiation exposure during MPS. 7 The INCAPS Study has assessed the adoption 175