IJCS | Volume 31, Nº4, July / August 2018

335 Table 1. Patients’ characteristics Age, years 65.45 (58.03-69.59) Female, % 65.96 Ethnicity, % White 63.83 Mixed-race 25.53 Black 10.64 Diagnosis, % Stable angina 82.98 Previous AMI 14.89 Others 2.13 SAH 91.11 Dyslipidemia 91.11 Diabetes Mellitus 42.22 Smoker 40.00 Cerebrovascular disease 8.89 Kidney failure 4.44 Sedentary lifestyle 86.67 Obesity 13.95 Family history 52.27 LVEF < 50% 14.28 EF Teichholz 64.5 (45-71) Three-vessel anatomy or LMCA 38.80 AMI: acute myocardial infarction; SAH: systemic arterial hypertension; LVEF: left ventricular ejection fraction; EF: ejection fraction; LMCA: left main coronary artery. sensor at its tip and was positioned in the distal bed of each coronary to be analyzed. Intravenous adenosine at the dose of 140 mg/kg/minute was administered for 2 to 3 minutes to induce maximal hyperemia. The FFR was established as the ratio between the mean distal coronary pressure and the mean aortic pressure, measured by the guide catheter duringmaximal hyperemia. Stenoses with FFR < 0.8 were considered positive for ischemia. Myocardial perfusion scintigraphy The MPS was performed using the Single-Photon Emission Computed Tomography (SPECT) technique, using technetium-99m sestamibi (Tc-99m MIBI) with the 2-day protocol at rest and exercise or dipyridamole stress test. The images were semi-quantitatively analyzed using a 17-segment model. The test was considered abnormal when it disclosed evidence of one or more ischemic areas. The percentage of ischemic area was not evaluated in all patients. Statistical analysis A descriptive analysis of the selected patients’ basal characteristics was performed by calculating medians and interquartile ranges. The assessment of the association between the presence of ischemia in the MPS and FFR was assessed using the two-tailed Fisher’s exact test. A p-value < 0.05 was considered statistically significant. The STATA/MP software by StatCorp LP, version 14.2, was used for data analysis. Results When characterizing the sample of assessed patients, 47 individuals with stable coronary disease and a median age of 65.4 years (interquartile range between 58.03 and 69.59 years) were selected. Most were women (66%) and had stable angina (82%); and 7% were post-acute myocardial infarction. Regarding left ventricular function, only 14% had moderate to severe dysfunction. The ejection fraction calculated by the Teichholz method showed a median of 64.5%, with an interquartile range between 45% and 71% (Table 1). The stress assessment by MPS was performed in 68% with dipyridamole and in 32% through an exercise stress test. The interval between MPS and FFR was 24.5 days between January 2013 and October 2015. In the analyzed sample of patients, 38.8% had a three-vessel lesion or had a left main coronary artery lesion. FFR was performed in the following territories: one left main coronary artery, 37 anterior descending arteries (ADA), 12 circumflex arteries and 4 right coronary arteries. In the comparative analysis of the MPS and FFR results, 83% of the patients with positive FFR also had positive MPS, but with a non-significant p value (0.058) and 53.57% of the patients with positive MPS had a negative FFR (Figure 1). When discriminating the assessment of the ADA territory, 83% of patients with negative FFR also had negative MPS, but in those who obtained positive FFR Issa et al. Comparison between Fraction Flow Reserve and SPECT in Myocardial Ischemia Int J Cardiovasc Sci. 2018;31(4)333-338 Original Article