Long-Term Outcome Up To 40 Years after Single Patch Repair of Complete Atrioventricular Septal Defect in Infancy or Childhood.

OBJECTIVES: Patients with repaired complete atrioventricular septal defect (CAVSD) represent an increasing portion of grown-ups with congenital heart disease. For repair of CAVSD, the single-patch technique has been employed first. This technique requires division of the bridging leaflets, thus, among other issues, long-term function of the atrioventricular valves is of particular concern. METHODS: Between 1978 and 2001, 100 consecutive patients with isolated CAVSD underwent single-patch repair in our institution. Hospital mortality was 11%. Primary endpoints were clinical status, atrioventricular valve function, and freedom from reoperation in long term. Follow-up was obtained contacting the patient and/or caregiver, and the referring cardiologist. RESULTS: Eighty-three patients were eligible for long-term follow-up (21.0 ± 8.7, mean ± standard deviation [21.5; 2.1-40.0, median; min-max] years after surgical repair). Actual long-term mortality was 3.4%. Quality of life (QoL; self- or caregiver-reported in patients with Down syndrome) was excellent or good in 81%, mild congestive heart failure was present in 16%, moderate in 3.6% as estimated by New York Heart Association classification. Echocardiography revealed normal systolic left ventricular function in all cases. Regurgitation of the right atrioventricular valve was mild in 48%, mild-moderate in 3.6%, and moderate in 1.2%. The left atrioventricular valve was mildly stenotic in 15% and mild to moderately stenotic in 2%; regurgitation was mild in 54%, mild to moderate in 13%, and moderate in 15% of patients. Freedom from left atrioventricular-valve-related reoperation was 95.3, 92.7, and 89.3% after 5, 10, and 30 years, respectively. Permanent pacemaker therapy, as an immediate result of CAVSD repair (n = 7) or as a result of late-onset sick sinus syndrome (n = 5), required up to six reoperations in single patients. Freedom from pacemaker-related reoperation was 91.4, 84.4, and 51.5% after 5, 10, and 30 years, respectively. CONCLUSION: Up to 40 years after single-patch repair of CAVSD, clinical status and functional results are promising, particularly, in terms of atrioventricular valve function. Permanent pacemaker therapy results in a life-long need for surgical reinterventions.

Long-term outcome of speech and language in children after corrective surgery for cyanotic or acyanotic cardiac defects in infancy.

The purpose of this prospective study was to assess whether outcome of speech and language in children 5-10 years after corrective surgery for tetralogy of Fallot (TOF) or ventricular septal defect (VSD) in infancy was influenced by the preoperative condition of hypoxemia or cardiac insufficiency and whether it was associated with perioperative risk factors and neurodevelopmental outcome. A total of 35 unselected children, 19 with TOF and hypoxemia and 16 with VSD and cardiac insufficiency, operated with combined deep hypothermic circulatory arrest and low-flow cardiopulmonary bypass at mean age 0.7+/-0.3 (mean+/-standard deviation) years, underwent, at mean age 7.4+/-1.6 years, standardized evaluation of speech and language functions. Results were compared between subgroups and related to perioperative factors, sociodemographic and neurodevelopmental status. Age at testing, socioeconomic status and history of speech and language development were not different between the subgroups. In contrast, total scores on oral and speech motor control functions (TFS) as well as on oral and speech apraxia (Mayo Test) were significantly reduced (p<0.02 to <0.05), and scores on anatomical oral structures tended to be lower (p<0.09) in the TOF group as compared to the VSD group. No differences were found for auditory word recognition and phonological awareness as assessed by the Auditory Closure subtest of the Illinois Test of Psycholinguistic Abilities and the test of auditory analysis skills, respectively. In all children, higher age at testing and better socioeconomic status were associated with better results in all domains of assessment (p<0.001 to <0.04). Consistent impairments of all oral and speech motor control functions (TFS and Mayo Test) were present in 29% of all children with a mean age of 6.5 years in contrast to 43% with normal performance and a mean age of 8.3 years. On the receptive speech tasks, only 6% scored below the normal range of their age group. TFS subscores were significantly correlated with age, bypass duration and motor function, but not correlated with socioeconomic status, duration of cardiac arrest, intelligence and academic achievement. Children with preoperative hypoxemia due to cyanotic cardiac defects in infancy are at higher risk for dysfunction in speech and language than those with cardiac insufficiency due to acyanotic heart defects. Age at testing, socioeconomic status, and duration of cardiopulmonary bypass influenced test results. Long-term outcome in speech and language functions can be considered as a sensitive indicator of overall child development after cardiac surgery.

Children undergoing cardiac surgery for complex cardiac defects show imbalance between pro- and anti-thrombotic activity.

INTRODUCTION: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with the activation of inflammatory mediators that possess prothrombotic activity and could cause postoperative haemostatic disorders. This study was conducted to investigate the effect of cardiac surgery on prothrombotic activity in children undergoing cardiac surgery for complex cardiac defects. METHODS: Eighteen children (ages 3 to 163 months) undergoing univentricular palliation with total cavopulmonary connection (TCPC) (n = 10) or a biventricular repair (n = 8) for complex cardiac defects were studied. Prothrombotic activity was evaluated by measuring plasma levels of prothrombin fragment 1+2 (F1+2), thromboxane B2 (TxB2), and monocyte chemoattractant protein-1 (MCP-1). Anti-thrombotic activity was evaluated by measuring levels of tissue factor pathway inhibitor (TFPI) before, during, and after cardiac surgery. RESULTS: In all patients, cardiac surgery was associated with a significant but transient increase of F1+2, TxB2, TFPI, and MCP-1. Maximal values of F1+2, TxB2, and MCP-1 were found at the end of CPB. In contrast, maximal levels of TFPI were observed at the beginning of CPB. Concentrations of F1+2 at the end of CPB correlated negatively with the minimal oesophageal temperature during CPB. Markers of prothrombotic activity returned to preoperative values from the first postoperative day on. Early postoperative TFPI levels were significantly lower and TxB2 levels significantly higher in patients with TCPC than in those with biventricular repair. Thromboembolic events were not observed. CONCLUSION: Our data suggest that children with complex cardiac defects undergoing cardiac surgery show profound but transient imbalance between pro- and anti-thrombotic activity, which could lead to thromboembolic complications. These alterations are more important after TCPC than after biventricular repair but seem to be determined mainly by low antithrombin III.

Introduction of a flexible polymeric heart valve prosthesis with special design for mitral position.

BACKGROUND: Current heart valve prostheses are constructed mimicking the native aortic valve. Special hemodynamic characteristics of the mitral valve such as a nonaxial central inflow with creation of a left ventricular vortex have so far not been taken into account. A new polycarbonaturethane (PCU) bileaflet heart valve prosthesis with special design for the mitral position is introduced, and results of animal testing are presented. METHODS AND RESULTS: After in vitro testing, 7 PCU-prostheses and 7 commercial bioprostheses (Perimount, n=4; Mosaic, n=3) were implanted in mitral position into growing Jersey calves (age 3-5 months, weight 60-97 kg) for 20 weeks. 2-Dimensional echocardiography was performed after implantation and before sacrification. Autopsy included histologic, radiographic, and electron microscopic examination of the valves. In vitro durability was proven for >15 years. After implantation 2-dimensional-echocardiography showed no relevant gradient or regurgitation of any prosthesis. Clinical course of the animals with PCU valves was excellent. In contrast, 5 of 7 calves with bioprostheses were sacrificed after 1-9 weeks because of congestive heart failure. 2-Dimensional echocardiography of the PCU valves after 20 weeks showed mild leaflet thickening with trivial regurgitation; mean gradient was 8.1+/-5.0 mm Hg (weight: 160-170 kg). The explanted PCU prostheses revealed mild calcification and no structural degeneration. All of the Perimount bioprostheses were severely calcified and degenerated after 11+/-7 weeks. One Mosaic bioprosthesis was thrombosed after 1 week, and 2 showed severe and mild-to-moderate degeneration after 4 and 22 weeks, respectively. CONCLUSIONS: Polycarbonaturethane valve prostheses with special design for mitral position show excellent hemodynamic performance and durability in vivo. Calcification and structural changes are mild compared with bioprostheses. Controlled clinical studies are planned.

Long-term neurodevelopmental outcomes in school-aged children after neonatal arterial switch operation.

OBJECTIVE: Neurodevelopmental status of children between 8 and 14 years of age after neonatal arterial switch operation for transposition of the great arteries has not previously been systematically evaluated. METHODS: Within a longitudinal study, 60 unselected children operated on as neonates with combined deep hypothermic circulatory arrest and low-flow cardiopulmonary bypass were reevaluated at the age of 7.9 to 14.3 years (mean +/- SD 10.5 +/- 1.6 years). Clinical neurologic status and standardized tests to assess gross motor function, intelligence, acquired abilities, language, and speech were carried out, and the results were related to preoperative, perioperative, and postoperative status, to management, and to neurodevelopmental status at a mean age of 5.4 years. RESULTS: Neurologic and speech impairments were evidently more frequent (27% and 40%, respectively) than in the general population. Intelligence and socioeconomic status were not different (P =.29 and P =.11), whereas motor function, acquired abilities, and language were reduced (P < or =.04 for each). Overall rate of developmental impairment in one or more domains was 55%, compared with 26% at age 5.4 years. Multivariable analysis showed that severe preoperative acidosis and hypoxia predicted reduced motor function (mean deficit 52.7 points, P <.001), whereas longer bypass duration predicted both neurologic (odds ratio per 10 minutes of bypass duration 1.8, P =.04) and speech (odds ratio per 10 minutes of bypass duration 1.9, P =.02) dysfunction, and perioperative and postoperative cardiocirculatory insufficiency predicted neurologic (odds ratio 6.5, P =.04) and motor (mean deficit 6.8 points, P =.03) dysfunction. CONCLUSIONS: The neonatal arterial switch operation with combined circulatory arrest and low-flow bypass is associated increasingly with age, with reduced neurodevelopmental outcome but not with cognitive dysfunction. In our experience, the risk of long-term neurodevelopmental impairment after neonatal corrective cardiac surgery is related to deleterious effects of the global perioperative management and to special adverse effects of prolonged bypass duration. Severe preoperative acidosis and hypoxia and postoperative hemodynamic instability must be considered as important additional risk factors.

Moderate hypothermia during cardiopulmonary bypass increases intramyocardial synthesis of heat shock protein 72.

OBJECTIVES: This study was undertaken to test the hypothesis that the myocardial protective effect of moderate hypothermia during cardiopulmonary bypass involves upward regulation of heat shock protein 72. METHODS: Sixteen young pigs were randomly assigned to a temperature regimen during standardized cardiopulmonary bypass of normothermia or moderate hypothermia (temperatures 37 degrees C and 28 degrees C, respectively, n = 8 per group). Myocardial probes were sequentially sampled from the right ventricle before and during bypass and 6 hours after bypass. Messenger RNA encoding for heat shock protein 72 was assessed by competitive reverse transcriptase-polymerase chain reaction, and heat shock protein 72 synthesis was assessed by Western blot and immunohistochemical methods. Induction of apoptosis was assessed by gene expression of apoptosis-regulating proteins (Bcl-xL, Bak, and Fas) according to competitive reverse transcriptase polymerase chain reaction. Apoptotic cells were identified with an in situ apoptosis-detection kit (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling) in combination with morphologic criteria. Necrotic cells were detected by standard histologic methods. RESULTS: Moderate hypothermia rather than normothermia was associated with earlier and higher gene expression and synthesis of heat shock protein 72 in the myocardium during and after cardiac surgery. In the hypothermia group both heat shock protein 72 and the messenger RNA encoding it were detected as soon as 30 minutes after initiation of bypass and before aortic clamping, whereas in the normothermia group they were not detected before aortic clamping. Immunohistochemical methods showed localization of heat shock protein 72 in the cardiomyocytes, endothelial cells, and macrophages. Although the percentage of necrotic cells in the myocardium was lower in the hypothermic group, the induction of apoptosis regulatory proteins and the percentage of apoptotic cells did not differ between the groups. CONCLUSIONS: These results suggest that the myocardial protective effect of moderate hypothermia during cardiopulmonary bypass involves upward regulation of heat shock protein 72 and inhibition of necrosis but not of apoptosis.

Production of proinflammatory cytokines and myocardial dysfunction after arterial switch operation in neonates with transposition of the great arteries.

OBJECTIVE: Neonates undergoing cardiac surgery have a systemic inflammatory reaction with release of proinflammatory cytokines, which could be responsible for myocardial dysfunction as a result of myocardial cell damage. The purpose of this study was to test the hypothesis that the production of proinflammatory cytokines during cardiac surgery would be associated with myocardial dysfunction after the arterial switch operation in neonates. METHODS: A total of 63 neonates with transposition of the great arteries were operated on with combined deep hypothermic circulatory arrest and low-flow cardiopulmonary bypass at a median age of 7 days. Perioperative plasma concentrations of interleukins 6 and 8 were correlated with myocardial dysfunction, as assessed clinically and by echocardiography within 24 hours after the operation, and with perioperative cardiac troponin T blood levels as a marker of myocardial cell damage. RESULTS: Myocardial dysfunction was observed in 11 patients (17.5%), and 2 of them died. Durations of cardiopulmonary bypass and aortic crossclamping, but not of circulatory arrest, were correlated with myocardial dysfunction. Patients with myocardial dysfunction had significantly higher cardiac troponin T blood levels at the end of cardiopulmonary bypass and 4 and 24 hours after the operation than did patients without myocardial dysfunction. Patients with myocardial dysfunction also had higher interleukin 6 plasma concentrations after cardiopulmonary bypass and 4 hours after the operation, as well as higher interleukin 8 plasma concentrations 4 and 24 hours after the operation, than did those without myocardial dysfunction. Postoperative interleukin 6 and 8 plasma concentrations were significantly correlated with postoperative cardiac troponin T blood levels. Multivariable analysis of independent risk factors for myocardial dysfunction comprising cytokine and troponin levels and bypass duration revealed interleukin 6 levels 4 hours after the operation as significant (P =.047). CONCLUSIONS: Cardiac operations in neonates stimulate the production of proinflammatory cytokines, which may contribute to myocardial cell damage and myocardial dysfunction.

Long-term results of cardiac and general health status in children after neonatal arterial switch operation.

BACKGROUND: The purpose of this study was to assess cardiac and general health status 8 to 14 years after neonatal arterial switch operation for transposition of the great arteries. METHODS: Sixty unselected children with intact ventricular septum (78.3%) or ventricular septal defect (21.7%) without or with aortic isthmic stenosis (5.1%) were examined 10.5 +/- 1.6 (mean +/- SD) years after neonatal switch and 5.3 +/- 1.6 years after mid-term evaluation. Complete clinical examination, standard and 24-hour Holter electrocardiogram, M-mode, 2D-, Doppler, and color Doppler echocardiography were performed. Results were compared with normal values and to mid-term follow-up results. RESULTS: Rates of reoperation after arterial switch operation and operation to correct concomitant coarctation were 3.3% and 5.1%, respectively. No patient needed medication, and 93.3% had no limitation of physical activity. All children had normal height and weight; 31.6% had abnormal thoracic configuration after median sternotomy. Most patients (91.7%) were in sinus rhythm. Incidence of complete right bundle branch block (10.0%) was unchanged, as was prevalence of ectopic activity (occasional atrial ectopy 20.0%, ventricular ectopy: occasional 21.7%; frequent 1.7%). Left ventricular dimensions and shortening fraction did not change over time. Diameters of neo-aortic valve annulus and neo-aortic root did not increase, and z-scores decreased between mid-term and present evaluation. Incidence of neo-aortic insufficiency was 13.3% and remained unchanged in comparison with the pre-examination value. Neo-aortic stenosis was not seen. Compared with mid-term follow-up, incidence (41.6%) and degree of supravalvular pulmonary stenosis increased. CONCLUSIONS: Good cardiac results persist 10 years after neonatal arterial switch operation for transposition of the great arteries. Encouraging findings include preservation of left ventricular function, low incidence of rhythm disturbances, lack of further neo-aortic root dilatation, and unchanged incidence of neo-aortic insufficiency compared with mid-term follow-up. Increased incidence and degree of supravalvular pulmonary stenosis are of concern.

Thromboembolic complications after Fontan procedures: comparison of different therapeutic approaches.

BACKGROUND: Although patients after Fontan procedure have a high incidence of thromboembolic complications, anticoagulant therapy is not handled uniformly. We analyzed the frequency and clinical relevance of thromboembolism after Fontan procedure and compared different therapeutic approaches. METHODS: From 1986 to 1998, 101 patients (mean age, 7.3 +/- 8.1 years) underwent Fontan type procedure (modified Fontan, n = 40; total cavopulmonary connection, n = 61). In 85 of 87 survivors, transthoracic echocardiography was performed; and in 31 transesophageal echocardiography and/or angiography was performed. Mean follow-up was 5.7 +/- 3.5 years. Three groups with different anticoagulant regimen were compared: group I without medication (n = 45), group II with acetylsalicylic acid therapy (n = 14) and group III with Coumadin (n = 26). RESULTS: Thromboembolic events occurred in 13 of 85 patients (15.3%; 3.3 events/100 patient-years). Type of operation as well as other known risk factors had no influence on the rate of thromboembolism. Within the first postoperative year, seven of 13 events occurred. A second peak developed beyond 10 years of follow-up. Patients benefit significantly from Coumadin compared with those who did not receive any medication, with similar results in the entire population and the subgroup of patients with total cavopulmonary connection (log-rank, p = 0.031 and p = 0.033, respectively). With 4.2 events/100 patient-years, the cumulative event rate was substantially higher in group I than with 1.6 in group II and with 1.1 in group III. No relevant bleeding complications occurred. CONCLUSIONS: Thromboembolism is frequent after Fontan procedure with a peak during the first postoperative year and another peak beyond 10 years of follow-up. Coumadin is the most effective prophylactic therapy in preventing thromboembolism. Therefore, we suggest initial oral anticoagulation therapy in patients with Fontan type operation.

Injury of the common peroneal nerve after cardiothoracic operations.

BACKGROUND: To assess incidence, etiology, and clinical relevance of common peroneal nerve injury (CPNI) in patients after cardiothoracic surgery. METHODS: In an 11-year period, CPNI was detected in 39 out of 20,718 patients (0.19%): 38 times after cardiopulmonary bypass (CPB) (38 of 12,726; 0.30%) and in 1 patient after a non-CPB procedure (1 of 7,992; 0.013%). These patients underwent intensive physiotherapeutic treatment. As the majority of CPNI occurred after CPB (97.4%), data of these patients were compared with a 1-year set of 1,032 patients who underwent CPB procedures. RESULTS: Patients with CPNI were older, had a higher percentage of subnormal body weight, and had considerable comorbidity such as peripheral arteriosclerotic disease, diabetes mellitus, and arrhythmias. Follow-up was complete (mean: 5.2 years; 0.4 to 10.7 years). Twenty-eight patients were free of symptoms; 10 patients complained of moderate symptoms, but were not limited in their everyday life; 1 patient still suffers from severe sensorimotor symptoms. CONCLUSIONS: CPNI after cardiothoracic surgery is rare. Duration of the operative procedure, an increased comorbidity, and a subnormal body weight are assumed to have an etiologic impact. Prognosis is mostly good, but early physiotherapeutic treatment is crucial for prognosis.

Cytokine balance in infants undergoing cardiac operation.

BACKGROUND: The control of the systemic inflammatory response taking place during cardiac operations depends on adequate antiinflammatory reaction. In this prospective study we tested the hypothesis that cytokine balance during pediatric cardiac surgical procedures would be influenced by the patients' preoperative clinical condition, defined as hypoxemia or heart failure. METHODS: Twenty infants (median age, 8 months) with hypoxemia owing to intracardiac right-to-left shunt (group 1, n = 10) or with heart failure because of intracardiac left-to-right shunt (group 2, n = 10), scheduled for elective primary corrective operation, were enrolled. Plasma levels of the proinflammatory cytokine interleukin (IL) 6, the natural antiinflammatory cytokine IL-10, and the markers of the acute-phase response, C-reactive protein and procalcitonin, were sequentially measured before, during, and after cardiac operation up to the 10th postoperative day. The ratio of IL-10 to IL-6 levels served as a marker for the individual's antiinflammatory cytokine balance. RESULTS: Group 1 showed higher preoperative IL-6 (p < 0.001), lower IL-10 levels (p < 0.02), and lower ratio of IL-10 to IL-6 levels (p < 0.001) than group 2. Preoperative C-reactive protein and procalcitonin were not detectable. In group 1, preoperative IL-6 levels inversely correlated with preoperative oxygen saturation (Spearman correlation coefficient, -0.74, p < 0.02). During cardiopulmonary bypass, IL-6 levels were higher, whereas IL-10 and ratio of IL-10 to IL-6 levels were lower in group 1 than in group 2. In all patients, postoperative IL-6 levels were positively correlated with duration of inotropic support and serum creatinine value and inversely correlated with oxygenation index and diuresis. CONCLUSIONS: Infants with hypoxemia show a preoperative inflammatory state with low antiinflammatory cytokine balance in contrast to those with heart failure. This in turn is associated with lower perioperative antiinflammatory cytokine balance and might contribute to postoperative morbidity.

Antegrade palliation for diminutive pulmonary arteries in Tetralogy of Fallot.

OBJECTIVES: The purpose of this study was to evaluate the outcome following palliative reconstruction of right ventricular outflow tract in Tetralogy of Fallot (TOF) with diminutive pulmonary arteries with central and peripheral stenosis. METHODS: Between 1986 and 1999 in 15 children with the diagnosis of TOF palliative reconstruction of the right ventricular outflow tract without closure of the ventricular septal defect (VSD) was performed. All patients were not suitable for an AP-Shunt because of a diminutive pulmonary vascular bed. Six patients were younger than 1 year at operation. RESULTS: There was one hospital death (6.7%) in a child with additional aortic valve insufficiency in multi-organ failure. Although the postoperative course was prolonged (median duration on ICU: 8 days) and complicated by congestive heart failure, clinically the 14 patients discharged improved significantly. The arterial oxygen saturation increased from 67 to 93% (P<0.001), the hemoglobin decreased from 16.1 to 13.3g/l (P=0.02) and hematocrit from 0.52 to 0.40 (P=0.06). In control angiography, the McGoon Index increased in the average from 1.01 to 1.95 (P<0.001). VSD closure was performed in 12 patients (median: 2.5 years after initial operation) with one perioperative death. A homograft had to be implanted in seven patients and a mechanical prosthesis in the right ventricular outflow tract in one. One late death occurred due to ventricular arrhythmia 12 years after antegrade palliation (11 years after corrective operation). CONCLUSIONS: The antegrade palliation seems to be an adequate strategy for the treatment of selected children with diminutive pulmonary arteries in TOF, who were not candidates for primary correction or an AP-Shunt.

Introduction of a flexible polymeric heart valve prosthesis with special design for aortic position.

OBJECTIVE: Current prosthetic heart valves necessitate permanent anticoagulation or have limited durability and impaired hemodynamic performance compared to natural valves. Recently a polymeric valve prostheses with special design for mitral position demonstrated excellent in vitro and in vivo results with improved durability and no need for permanent anticoagulation. In this study, a respective flexible polymeric aortic valve is presented and in vitro and in vivo results are reported. METHODS: The aortic prosthesis (ADIAM lifescience AG, Erkelenz, Germany) is entirely made of polycarbonaturethane. The tri-leaflet flexible prosthesis mimicks the natural aortic valve and has a diminished pressure loss and reduced stress and strain peaks at the commissures. The valve underwent long-term in vitro testing and in vivo-testing in a growing calve animal model (20 weeks, 7 aortic valves) and was compared to two different commercial bioprostheses. RESULTS: The polymeric aortic heart valve substitute demonstrated excellent in vitro and in vivo hemodynamics. Five/seven animals with aortic PCU-prostheses had an excellent clinical long-term course. The explanted valves showed a variable degree of calcification. Two of the seven animals died at 27 and 77 days due to pannus overgrowth causing severe LVOTO without degeneration of the valve itself. Both animals with commercial bioprostheses had to be sacrificed because of congestive heart failure related to structural degeneration of the bioprosthesis after 10 and 30 days of implantation. There was no increased thrombogenity of the PCU valves compared to bioprostheses. CONCLUSION: The new flexible polymeric aortic valve prosthesis is superior to current bioprostheses in animal testing.

New flexible polymeric heart valve prostheses for the mitral and aortic positions.

OBJECTIVE: Current prosthetic heart valves necessitate permanent anticoagulation or have limited durability and impaired hemodynamic performance compared with natural valves. We report in vivo and in vitro results with new polymeric valve prostheses that have a special design for the mitral and aortic positions. The aims are improved durability and elimination of the need for permanent anticoagulation. METHODS: The mitral and aortic prostheses (Adiam Life Science, Erkelenz, Germany) are made entirely of polycarbonate urethane (PCU). The bileaflet asymmetric mitral valve mimics natural, nonaxial inflow, which creates a left ventricular vortex, saving energy for systolic ejection of blood. The trileaflet aortic prosthesis has diminished pressure loss and reduced stress and strain peaks at the commissures. The valves were subjected to long-term in vitro testing and in vivo testing in a growing calf model (20 weeks; 7 mitral and 7 aortic valves) with comparison with 2 commercial bioprostheses (7 mitral, 2 aortic). Two-dimensional echocardiography was performed after implantation and prior to sacrifice with autopsy and valve examination. RESULTS: In vitro durability of the PCU valves was proved up to 20 years. In vivo durability and hemodynamics were superior to those of all bioprostheses. Survival of PCU valves versus bioprostheses was 7 versus 2 mitral valves and 5 versus 0 aortic valves, respectively. Two animals with PCU aortic valves died of pannus overgrowth that caused severe left ventricular outflow tract obstruction without changes in the valves. Degeneration and calcification were mild (mitral) and moderate (aortic) in PCU valves but were severe in biological valves. There was no increased thrombogenicity of the PCU valves compared with bioprostheses. CONCLUSION: The new flexible polymeric aortic and mitral valve prostheses were superior to current bioprostheses in animal testing.

Neurologic and psycho-intellectual outcome related to structural brain imaging in adolescents and young adults after neonatal arterial switch operation for transposition of the great arteries.

OBJECTIVE: We studied brain structure abnormalities in adolescents and young adults who had undergone the neonatal arterial switch operation for transposition of the great arteries and related them to the neurologic and psycho-intellectual outcomes. METHODS: In a prospective longitudinal study, 60 unselected adolescents and young adults who had undergone surgery with combined deep hypothermic circulatory arrest and low flow cardiopulmonary bypass were re-evaluated at a mean age of 16.9±1.7 years to determine their clinical neurologic status, intellectual development, and psychological condition. The results were related to population norms and anatomic structural abnormalities assessed by brain magnetic resonance imaging, with consideration of the risk factors in the preoperative and perioperative periods. RESULTS: Neurologic impairment was more frequent (10%) than in the normal population. Although the average full-scale, verbal, and performance intelligence quotients were not reduced, scores>2 standard deviations less than the expected mean were increased. Above average scores were found for analytical thinking, but the orthography testing results were reduced. The self-rated psychological condition was better than expected. Magnetic resonance imaging demonstrated moderate or severe structural brain abnormalities in 32% of the patients. Periventricular leukomalacia was detected in >50%; its severity correlated with the grade of neurologic impairment, which correlated significantly with reduced intelligence, analytical thinking, and orthography. Preoperative acidosis and hypoxia were the only independent patient-related risk factors for neurologic dysfunction, reduced intelligence, periventricular leukomalacia, and reduced brain volume. CONCLUSIONS: Despite encouraging overall neurodevelopmental outcomes, a significant minority had performances below the expected level, emphasizing the need for ongoing surveillance. Considering the high frequency of structural brain abnormalities, prospective long-term studies are needed to define their prognostic value with respect to the neuropsychological outcomes in childhood and adolescence.

Prevalence of and risk factors for perioperative arrhythmias in neonates and children after cardiopulmonary bypass: continuous holter monitoring before and for three days after surgery.

BACKGROUND: A comprehensive evaluation of postoperative arrhythmias following surgery for congenital heart disease by continuous Holter monitoring has not been carried out. We aimed, firstly, to establish the time course of pre- and early postoperative arrhythmias by beat-to-beat analysis following cardiopulmonary bypass and, secondly, to examine which surgical procedures present risk factors for specific arrhythmias. METHODS: 494 consecutive patients, including 96 neonates, were studied with serial 24-hour Holter electrocardiograms before as well as uninterruptedly during the first 72 hours after surgery and prior to discharge. RESULTS: Within 24 hours of surgery 59% of the neonates and 79% of the older children developed arrhythmias. Junctional ectopic tachycardia occurred in 9% of neonates and 5% of non-neonates and ventricular tachycardia in 3% and 15%, respectively.For neonates, male sex and longer cross-clamping time independently increased the risk for arrhythmias (odds ratios 2.83 and 1.96/minute, respectively). Ventricular septal defect repair was a strong risk factor for junctional ectopic tachycardia in neonates and in older children (odds ratios 18.8 and 3.69, respectively). For infants and children, older age (odds ratio 1.01/month) and closure of atrial septal defects (odds ratio 2.68) predisposed to arrhythmias of any type. CONCLUSIONS: We present the largest cohort of neonates, infants and children that has been prospectively studied for the occurrence of arrhythmias after cardiac surgery. Postoperative arrhythmias are a frequent and transient phenomenon after cardiopulmonary bypass, provoked both by mechanical irritation of the conduction system and by humoral factors.

Attentional dysfunction in children after corrective cardiac surgery in infancy.

BACKGROUND: Attentional dysfunction in children after corrective cardiac surgery in infancy has rarely been evaluated and is the topic of the present work. METHODS: Forty unselected children, 20 with tetralogy of Fallot and hypoxemia and 20 with ventricular septal defect and cardiac insufficiency, operated on at a mean age 0.7 (SD 0.3) years with deep hypothermic circulatory arrest and low flow cardiopulmonary bypass, were evaluated at mean age 7.4 (SD 1.6) years by the computerized form of the Attention Network Test providing performance measures of three networks of attention: alerting, orienting, and executive control. Parental ratings of attentional dysfunction were derived from the Child Behavior Checklist. Results were compared with healthy controls, between patient groups, and correlated with perioperative risk factors and current neurodevelopmental status. RESULTS: Executive control was reduced in the tetralogy of Fallot group, alerting and orienting were found normal and not different between patient groups. Durations of aortic cross clamping inversely correlated with orienting; durations of cardiopulmonary bypass correlated with mean reaction time and inversely correlated with executive control. Motor function and acquired abilities correlated with executive control and orienting. Parent-reported problems on the Child Behavior Checklist inversely correlated with executive control and mean accuracy. CONCLUSIONS: Children with preoperative hypoxemia in infancy due to cyanotic cardiac defects are at increased risk for attentional dysfunction in the field of executive control, compared with normal children and with those who have acyanotic heart defects. Besides unfavorable perioperative influences, preoperative hypoxemia is considered responsible for additional damage to the highly oxygen sensitive regions of the prefrontal cortex and striate body assumed to be associated with the executive control network of attention.