ABC | Volume 112, Nº2, February 2019

Brief Communication Miranda et al Analysis of iron metabolism in CCC Arq Bras Cardiol. 2019; 112(2):189-192 Table 1 – Demographic, clinical, laboratory and echocardiographic characteristics of the IND, CCC and NCh groups Characteristics IND (n = 40) CCC (n = 40) NCh (n = 40) p Age* 49.68 ± 5.28 50.98 ± 5.88 49.20 ± 10.09 0.929 Height (cm) 1.69 ± 0.065 1.97 ± 0.158 1.94 ± 0.123 0.889 Weight (kg)* 79.100 ± 8.58 73.75 ± 10.15 71.88 ± 11.47 0.621 Male [n(%)] 21/40 (52.2%) 20/40 (50%) 5/40 (12.5%) 0.979 NYHA functional class - - - - I 40/40 (100%) 12/40 (30%) 32/40 (80%) 0.410 II - 15/40 (37.5%) 6/40 (15%) 0.510 III - 8/40 (2.5%) 0.312 IV - 5/40 (12.5%) 1/40(2.5%) 0.112 FeSe (μg/dL)* 125.30 ± 22.79 93.15 ± 36.53 114.77 ± 18.90 0.004 Hb (g/dL)* 14.84 ± 1.56 13.62 ± 1.23 14.02 ± 1.25 0.010 TSI (%)* 30.95 ± 7.06 29.48 ± 6.59 39.70 ± 8.54 0.001 TIBC (μg/dL )* 196.52 ± 56.95 297.30 ± 36.46 275.18 ± 33.48 0.001 Ferritin (ng/mL)** 156.25 (1.7-42.20) 134.5 (1.56-42.36) 112.95 (2.8-42.66) 0.004 LVD (mm)* 46.38 ± 7.34 65.43 ± 7.70 46.38 ± 7.34 0.002 E/e’ ratio* 6.6 ± 2.82 14.9 ± 4.58 12.15 ± 12.06 0.001 LVEF** 65.85 ± 5.9 35.92 ± 8.59 34.95 ± 8.12 0.001 NYHA: New York Heart Association functional class; FeSe: serum iron; Hb: hemoglobin; TSI: transferrin saturation index; TIBC: total iron binding capacity; LVD: diameter of the left ventricle in diastole; E/e: diastolic velocity; LVEF: ejection fraction of the left ventricle. Table 2 – Variables of iron kinetics markers independently associated with left ventricular systolic dysfunction below 35% (multivariate Cox Hazard proportional hazard model) Univariate model Multivariate model Variables OR 95% CI X 2 p OR 95% CI X 2 p TSI% 0.89 0.816-0.979 5.86 0.015 1.12 1.02-1.22 6.3 0.012 FeSe 0.97 0.95-0.99 5.34 0.021 1.23 1.00-1.04 5.9 0.014 FERRITIN 1.27 1.044-1.56 5.65 0.017 - - - - Creatinine 1.01 7.54 ± 13.7 1.36 0.243 - - - - GFR, mL/min/1.73 m 1.00 0.95-1.05 1.41 0.786 - - - - Hb 0.99 0.56-1.74 0.001 0.99 - - - - Anemia 8.97 1.01-7.90 3.90 0.04 1.22 0.126-11.83 0.030 0.862 Univariate and multivariate logistic regression analysis of laboratory parameters. FeSe: serum iron; Hb: hemoglobin; TSI: transferrin saturation index; GFR: glomerular filtration rate. Regarding the analysis of the iron kinetics markers and the echocardiographic variables, we found that the higher the systolic ventricular dysfunction, the lower the serum FeSe, TSI, TIBC, and ferritin levels. This finding is interesting because it reinforces our hypothesis that low levels of iron kinetics markers correlate with the degree of ventricular dysfunction. In the multivariate analysis, we found low levels of FeSe (p = 0.014) and TSI (p = 0.012), as well as statistically significant results for gender (p = 0.038) as independent markers for left ventricular systolic dysfunction. The fall of ten units of iron is associated with a 23% higher chance of occurrence of systolic ventricular dysfunction. The fall of ten units of TSI is associated with a 12% higher chance of occurrence of systolic ventricular dysfunction. Conclusion In the population studied, analyzes of iron metabolism in patients with CCC showed that there is an association with the degree of myocardial impairment, and the lower the iron serum levels, the total iron binding capacity, the transferrin saturation index and ferritin, the greater the degree of ventricular dysfunction. It is concluded that in chagasic cardiopathy there is a change in the ironmetabolism, and it is more pronounced than in non-chagasic cardiopathies, thus evidencing its infectious nature. 191