Neuro-developmental outcome in single-ventricle patients: is the Norwood procedure a risk factor?

OBJECTIVES: Complex neonatal surgery is considered a risk factor for neuro-developmental impairment in single-ventricle patients. Neuro-developmental outcome was compared between preschool-aged Fontan patients who underwent a Norwood procedure and single-ventricle patients not requiring neonatal surgery with cardiopulmonary bypass. METHODS: Verbal, performance and full-scale intelligence quotient (IQ) were evaluated with the Wechsler Preschool and Primary Scale of Intelligence. Cognitive functions were assessed with the German 'Kognitiver Entwicklungstest für das Kindergartenalter' (KET-KID). Risk factors for impaired neuro-development were evaluated. RESULTS: Neuro-developmental assessment was completed in 95 patients (Norwood: n = 69; non-Norwood: n = 26). Median (interquartile range) IQ and KET-KID scores were in the normal range. Except for verbal KET-KID, scores did not differ between Norwood and non-Norwood patients (verbal IQ: 98 (86-105) vs 93 (85-102), P = 0.312; performance IQ: 91 (86-100) vs 96 (86-100), P = 0.932; full-scale IQ: 93 (86-101) vs 89 (84-98), P = 0.314; KET-KID verbal: 48 (17-72) vs 25 (2-54), P = 0.020; KET-KID non-verbal: 33 (18-62) vs 45 (15-54), P = 0.771; KET-KID global: 42 (14-65) vs 28 (6-63), P = 0.208). Full-scale IQ was below average (<85 points) in 14 (20%) Norwood and 9 (35%) non-Norwood cases (P = 0.181). Global KET-KID was below average (<16th percentile) in 19 (28%) and 10 (38%) patients (P = 0.326). Smaller head circumference z-score and complications before neonatal surgery were independently associated with lower scores. CONCLUSIONS: Neuro-developmental outcome of preschool-aged Fontan patients was in the normal range. The Norwood procedure was not a risk factor for neuro-developmental impairment. Preoperative condition and patient-related factors were more important determinants than variables related to surgical palliation.

Neurodevelopmental outcome in hypoplastic left heart syndrome: Impact of perioperative cerebral tissue oxygenation of the Norwood procedure.

OBJECTIVES: Patients with hypoplastic left heart syndrome are at risk for neurodevelopmental impairment. Hypoxic-ischemic brain injury during neonatal treatment might be a relevant cause. We evaluated the association between cerebral oxygenation in the perioperative course of the Norwood procedure and neurodevelopmental outcome. METHODS: Cerebral tissue oxygen saturation (ScO2) was obtained by near-infrared spectroscopy for 24 hours before and 48 hours after surgery in 43 patients. Full-scale, verbal, and performance IQ scores were evaluated with the Wechsler Preschool and Primary Scale of Intelligence at a median of 4.5 years (range, 3.5-6.8 years). Cognitive functions were assessed with the German Kognitiver Entwicklungstest für das Kindergartenalter (KET-KID). RESULTS: Mean IQ scores and KET-KID percentile ranks were in the lower-normal range (full-scale IQ, 94 ± 11; verbal IQ, 97 ± 13; performance IQ, 93 ± 9; KET-KID global, 42 ± 27; verbal, 48 ± 29; nonverbal, 37 ± 23). Scores were below average (full scale IQ <85 or KET-KID <16th percentile) in 12 cases. Mean preoperative ScO2 was lower in patients scoring below average (56.8% ± 7.1% vs 61.7% ± 5.8%; P = .028) and was correlated with full-scale IQ (r = 0.495; P = .001), verbal IQ (r = 0.524; P = .001), and performance IQ (r = 0.386; P = .012) scores, and with global (r = 0.360; P = .018) and verbal (r = 0.395, P = .009) KET-KID scores. A relationship between IQ or KET-KID scores and postoperative ScO2 was not found. Gestational age, head circumference z-score, age at surgery, and postoperative length of stay were associated with IQ and KET-KID scores. CONCLUSIONS: Neurodevelopmental outcome was in the lower-normal range. Along with innate patient factors, preoperative cerebral tissue oxygenation is likely an important determinant of cognitive development.

Neuropsychological performance of school-aged children after staged surgical palliation of hypoplastic left heart syndrome.

OBJECTIVES: Despite advances in perioperative management during surgical treatment of hypoplastic left heart syndrome (HLHS), patients are still at risk for adverse neurodevelopmental sequelae including cognitive dysfunction. This study aimed to assess a neuropsychological profile of HLHS patients at school age who underwent the Norwood operation between 1996 and 2003 with deep hypothermic circulatory arrest (DHCA) or antegrade selective cerebral perfusion (ASCP), respectively. METHODS: Forty HLHS patients (DHCA: n = 11 and ASCP: n = 29) were compared with healthy controls (DHCA controls: n = 10 and ASCP controls: n = 24), recruited according to age, sex and socioeconomic status. Neuropsychological assessment included non-verbal intelligence (IQ norms) and raw score measures of visual and verbal short- and long-term memory as well as executive functions, processing speed and concentration. Neuropsychological data were correlated with bypass and circulatory arrest times. RESULTS: Compared with control subjects, both patient groups had average non-verbal intelligence scores [DHCA: 102 (72-112) and ASCP: 92 (70-127)], but showed reduced long-term memory capacities and decreased executive performance as well as reduced processing speed. DHCA patients, furthermore, had a reduced visual attention span, and ASCP patients scored less on the verbal learning task than controls. The duration of DHCA and cardiopulmonary bypass (CPB) was associated with visual executive functions and short-term memory. In the DHCA group, the duration of DHCA was correlated with the time to complete the Trail Making Test A measuring visual executive functions (Spearman rank correlation, rS = 0.867, P = 0.018). In patients provided with ASCP, the cumulated CPB duration was negatively correlated with the score of the block span test measuring visual short memory (rS = -0.476, P = 0.020) as well as with the copy score of the Rey Figure assessing visual executive functions (rS = -0.399, P = 0.032). CONCLUSIONS: School-age children with HLHS who underwent the Norwood procedure either with DHCA or ASCP show cognitive impairments compared with healthy controls. Our data indicate deficits in specific cognitive domains such as memory, executive functions and processing speed rather than basic intellectual dysfunction.