ABC | Volume 113, Nº4, October 2019

Original Article Cruz et al. Surgical mitral valvuloplasty in paediatric patients Arq Bras Cardiol. 2019; 113(4):748-756 Table 2 – Description of surgical and echocardiographic variables in the preoperative and immediate postoperative periods of 54 children and adolescents with rheumatic mitral insufficiency undergoing mitral valvuloplasty Variables Preoperative Mean ± SD Post-operative Mean ± SD p value Duration of ECC (min) 62.7 ± 17.8 --- --- Duration of anoxia (min) 50.0 ± 15.7 --- --- Duration of VAD use (days) --- 1.0 (1.0 - 2.0) --- Ejection fraction (%) 70.2 ± 8.5 54.8 ± 13.9 0.015 § Dilation of left chambers n (%) No 01 (2.0) 06 (11.1) 0.063 ¥ Yes 48 (98.0) 32 (84.2) Mitral stenosis Absent/discrete 46 (93.9) 36 (94.7) 1.000 ¥ Moderate/significant 03 (6.1) 02 (5.3) Aortic insufficiency Absent/discrete 36 (73.5) 30 (78.9) 1.000 ¥ Moderate/significant 13 (26.5) 08 (21.1) Aortic stenosis Absent/discrete 49 (100.0) 38 (100.0) --- Mitral insufficiency Absent/discrete 01 (2.0) 32 (84.2) 0.000 ¥ Moderate/significant 48 (98.0) 06 (15.8) Tricuspid insufficiency Absent/discrete 36 (73.5) 31 (81.6) 0.508 ¥ Moderate/significant 13 (26.5) 07 (18.4) Pulmonary hypertension No 11 (22.4) 31 (81.6) 0.000 ¥ Yes 38 (77.6) 07 (18.4) ECC: extracorporeal circulation; VAD: vasoactive drug; § paired Student’s t test; ¥ McNemar test. anoxia, both with p < 0.05. Age, weight, height, gender, origin, outpatient follow-up, disease duration until surgery, functional classification, surgical team, surgery events and duration of extubation had no statistically proven relationship. When the variables of the echocardiogram were studied in the immediate and late postoperative period, as shown in Table 4, the relationship between the presence of outcomes with MI, TI, and PH is statistically significant. In preoperative echocardiography, no relationship of statistical significance with the outcomes was found. Predictive variables The predictive variables are presented in Table 5. In the final model, the variable duration of VAD use was found as an independent predictor for the immediate outcome, presenting OR 2.5 (95%CI, 1.3-4.9), while no independent predictor was found for the late outcome. The duration of ECC was close to statistical significance. Discussion MVP is universally accepted as superior to valve replacement (bioprostheses ormetal prostheses), especially in children inwhom growth, problems with anticoagulation, thromboembolism, rapid valve degeneration, increased risk of endocarditis and less preservation of ventricular function are unfavourable factors to this technique. 6-8,10-12 In the tertiary hospital in which the study was performed, MVP is the preferred technique. Patients in the study were followed up for two months after MVP, and in that period, there were no deaths in the sample studied. This is in accordance with the literature, in which the precocious or hospital mortality rate ranged from 0.9 to 3.5%. 7,12,13 The literature lacks in studies that identify probable clinical predictors of negative outcomes in patients undergoing MVP surgery. In the present study, PH presented statistical significance for both immediate (≤7 days) and late (up to 60 days) postoperative outcomes in the univariate analysis, 751