IJCS | Volume 31, Nº4, July / August 2018

DOI: 10.5935/2359-4802.20180021 Abstract Background: Moderate coronary artery lesions can be, or not, responsible for myocardial ischemia. The functional analysis of these lesions can be performed by invasive and noninvasive methods. Objective: To compare the functional analysis of moderate coronary lesions by fractional flow reserve and myocardial perfusion scintigraphy. Methods: 47 patients with stable coronary artery disease and at least one moderate coronary artery obstruction were prospectively studied. They were submitted to fractional flow reserve and myocardial perfusion scintigraphy with a median interval of 24.5 days between January 2013 and December 2015. There was no change in clinical status or revascularization procedure between the exams. The population variables were described as medians and interquartile range. Fractional flow reserve was performed in one left main coronary artery; 37 left descending coronary arteries; 12 circumflex arteries and 4 right coronary arteries. Fractional flow reserve < 0.8 was considered positive. The comparative analysis between the results of the tests was performed by two-tailed Fisher’s test and a p-value ≤ 0.05 was considered significant. Results: Fractional flow reserve < 0.8 was found in the left main coronary artery (100%); 13 in the left descending coronary artery (35.14%); 6 in circumflex artery (50%) and 2 in the right coronary artery (50%). Among the patients with positive fractional flow reserve, 83% had myocardial ischemia demonstrated by the myocardial perfusion scintigraphy (p = 0.058). When analyzing specifically the left descending coronary artery, 83% of the patients with negative fractional flow reserve showed no ischemia at the myocardial perfusion scintigraphy, but 69% of the patients with positive fractional flow reserve showed no ischemia at the myocardial perfusion scintigraphy (p = 0.413). Conclusion: Disagreements can occur between the results of the functional analysis of moderate coronary lesions by invasive and noninvasive tests. (Int J Cardiovasc Sci. 2018;31(4)333-338) Keywords: Myocardial Ischemia; Praqctional Flow Reserve, Myocardial; Myocardial Perfusion / Diagnostic Imaging; Microvascular Angina. Introduction The presence of myocardial ischemia is one of the important prognostic factors in coronary artery disease (CAD) and in the decision-making on the best treatment to be implemented. The combination of coronary anatomy and information on the hemodynamic implication of the obstructive lesion is essential to define the treatment strategy to be carried out in patients with CAD. The fractional flow reserve (FFR) measurement is a valuable tool to evaluate the functional severity of a coronary stenosis, identifying changes in coronary flow resistance. The FFR can be obtained in the hemodynamic laboratory and can be performed together with the angiography. The FFR is defined as the maximum blood flow to the myocardium in the presence of a certain stenosis, divided by this flow, if there was no such stenosis. The FFR can be determined by dividing the 333 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2018;31(4)333-338 Mailing Address: Aurora Felice Castro Issa Rua Timóteo da Costa, 623/110. Postal Code: 22450-130, Leblon, Rio de Janeiro, RJ - Brazil E-mail: auroraissa@gmail.com; auroraissa@cardiol.br Comparison between Myocardial Ischemia Evaluation by Fractional Flow Reserve and Myocardial Perfusion Scintigraphy Aurora Felice Castro Issa, Felipe Pittella, Sergio Martins Leandro, Patricia Paço, Judas Tadeu, Renata Felix Instituto Nacional de Cardiologia, Rio de Janeiro, RJ - Brazil Manuscript received November 27, 2016, revised manuscript October 18, 2017, accepted November 13, 2017.