Outcomes of Supra-annular Mechanical Atrioventricular Valve Replacement with Polytetrafluoroethylene Graft in Infants and Children.

Despite improvements in valve repair techniques, conditions in which infants and children need for mechanical valve replacement (MVR) are still present. We analyzed supra-annular MVR outcomes in infants and children with small annulus and compared them with conventional annular MVR outcomes. Data were collected retrospectively from medical records of infants and children (weighing < 20 kg) who underwent atrioventricular valve replacement with mechanical valve in Seoul National University Children's Hospital between December 1984 and January 2019. We identified 8 patients (median age 20 months, median weight 10.2 kg) who underwent supra-annular MVR with polytetrafluoroethylene graft (supra-annular group). The patients were diagnosed with congenital mitral valve malformation (5 patients), complete atrioventricular septal defect (2 patients), and functional single ventricle (1 patient). The implanted mechanical valve size ranged from 16 to 23 mm. Thirty-three patients (median age 40 months, median weight 13 kg) underwent conventional annular MVR (annular group). The survival rate was not significantly different between the supra-annular and annular groups (75.0 vs 78.8%, P = 0.816). In patients with biventricular repair (7 patients with supra-annular MVR and 28 patients with annular MVR), mechanical valve-to-mitral valve annulus size ratio was higher in the supra-annular group than in the annular group (1.24 ± 0.30 vs 0.96 ± 0.22, P = 0.035). No coronary complication or heart block were observed in the supra-annular group. Supra-annular MVR with polytetrafluoroethylene graft may be a feasible surgical option in children with a small annulus when valve repair is unsuccessful.

Outcomes after extracardiac Fontan procedure with a 16-mm polytetrafluoroethylene conduit.

OBJECTIVES: We evaluated the outcomes of patients who underwent extracardiac Fontan circulation procedures (ECFP) and received 16-mm polytetrafluoroethylene conduits. METHODS: From June 1997 to May 2015, among the 408 patients who underwent ECFP, 66 patients (Group S) also received 16-mm polytetrafluoroethylene conduits. To compare this patient cohort with similarly sized patients who received larger conduits, a matched cohort (66 patients, Group L) was selected according to age and body weight. RESULTS: The mean age, body weight and Nakata index at ECFP in Groups S and L were 2.9 ± 1.2 and 3.1 ± 1.2 years (P = 0.243), 13.0 ± 2.4 and 13.0 ± 2.3 kg (P = 0.101), 175.3 ± 59.0 and 236.1 ± 75.1 mm2/m2 (P = 0.005), respectively. The mean follow-up periods for Groups S and L were 7.8 ± 6.0 and 9.1 ± 4.9 years (P = 0.150), respectively. The conduit size of Group L was 19.2 ± 1.4 mm (P < 0.001). There was no significant difference in mortality between the groups (P = 0.109). The freedom from reoperation was 94.0 ± 3.4% in Group S and 79.3 ± 5.7% in Group L after 10 years (P = 0.070). Late-occurring morbidities included protein-losing enteropathy (2 in Group S, 4 in Group L; P = 0.491) and thromboembolism (0 in Group S, 4 in Group L; P = 0.206). There was a significant difference in conduit-related events between the groups (1 in Group S, 5 in Group L; P = 0.031). In a paired cohort from the 2 groups including patients who were followed-up for more than 10 years (15 patients from each group), the body mass index was 51.0 ± 33.2% in Group S and 30.3 ± 34.2% in Group L. The decreases in the conduit cross-sectional areas for the paired patients in Group S (n = 20) and Group L (n = 20) were 14.9 ± 19.7% and 24.5 ± 15.5% (P = 0.076), respectively. Coarse liver parenchyma was detected in 9 of 23 (39.1%) patients from Group S and in 7 of 18 (38.8%) patients from Group L upon ultrasonography. CONCLUSIONS: The 16-mm polytetrafluoroethylene conduit for ECFP showed acceptable outcomes and good haemodynamic status in small-sized patients. According to our results, small patients do not require large conduits to accommodate their growth potential.