Major infection after pediatric cardiac surgery: external validation of risk estimation model.

BACKGROUND: A multivariable risk estimation model, in which the primary outcome was major infection, was recently developed and published using The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database. We have applied this risk estimation model to our congenital heart surgery program over a 16-year time interval to validate this risk estimation model and verify its specific risk factors for major infection. METHODS: Using complete and verified data, we selected patients in whom major procedures had been classified using both Aristotle Basic Score and Risk Adjustment for Congenital Heart Surgery (RACHS-1) and created a multivariable model in which primary outcome was major infection (septicemia, mediastinitis, or endocarditis). We checked the STS risk estimation model for major infection. We also assessed the significance of the STS risk factors in our program. RESULTS: A total of 6,314 patients were analyzed. We identified 197 (3.1%) major infections (septicemia 3%, endocarditis 0.015%, mediastinitis 0.09%). Hospital mortality, ventilation time, and length of stay were greater in patients with major infections. The following preoperative risk factors identified by the STS risk estimation model were significant in multivariate analysis in our patients: young age, high complexity, medium complexity, previous operation, and preoperative ventilation (p<0.0001). Estimated infection risk ranged from 0.32% to 11.58%. The model discrimination was good (c index, 0.808). Risks of infections after most common congenital heart surgery procedures were similar in both studies (rs=0.952, p=0.0003). CONCLUSIONS: Our external validation study confirmed that the STS model can be used as a preoperative risk stratification tool for major infection risk at the single institutional level.

Late right pulmonary artery stenosis after arterial switch operation in mirror image dextrocardia and situs inversus totalis.

The operation of D-transposition of the great arteries is performed extremely rarely in patients with mirror image dextrocardia and situs inversus totalis. Therefore, it is not surprising that such unusual anatomy case presents problems with primary operation. We present a case of late right pulmonary artery stenosis after neonatal surgical anatomic correction of mirror image dextrocardia and situs inversus totalis.

Acute and late obstruction of a modified Blalock-Taussig shunt: a two-center experience in different catheter-based methods of treatment.

Modified Blalock-Taussig (B-T) shunt occlusion results in a sudden reduction of pulmonary vascular perfusion, causing dramatic saturation drop and cyanosis which pose a direct hazard to a child's life. The results of percutaneous local r-tpa infusion, balloon angioplasty and additionally stent implantation in obstructed modified B-T shunts were studied to assess their role as an alternative to a re-do surgery. We outline two pediatric centers' experience (period 2004-2008) regarding the effectiveness of various emergency treatment methods for occlusion or critical stenosis of systemic-to-pulmonary arterial shunts in 23 children. Local r-tpa infusion via catheter was performed in 12/23 patients, balloon angioplasty in 22/23 and additionally stent implantation in 3/23 children. Procedures were successful in 22/23 patients (96%), with an increase in arterial saturation [average: 30%; standard deviation (S.D.) 15%; Shapiro-Wilk test; dependent t-test-P<0.01]. Unrestricted contrast flow was achieved in 18 patients, reduced central flow in three and minimal flow in one child. Neither local nor systemic complications occurred. Our experience demonstrates the possibility of successful early shunt recanalization with the use of local thrombolytic therapy combined with the balloon angioplasty. The presence of old fixed thrombus with neointimal hypertrophy in the shunt constitutes an indication for endovascular stent implantation.

Chromosome 22q11.2 microdeletion in children with conotruncal heart defects: frequency, associated cardiovascular anomalies, and outcome following cardiac surgery.

The association of conotruncal heart defects with 22q11.2 chromosomal microdeletions is well established. However, it is not clear whether particular types of conotruncal malformations or additional cardiovascular anomalies are associated with microdeletions. In addition, cardiac surgery outcome in children with conotruncal defects and del22q11.2 is not well described. We prospectively enrolled 214 children with conotruncal defects: 126 with tetralogy of Fallot (TOF), 18 with pulmonary atresia-ventricular septal defect (PA-VSD), 15 with truncus arteriosus communis (TAC) type I, one with interrupted aortic arch (IAA) type B, and 54 with the transposition of great arteries, who were consecutively hospitalized at the Pediatric Cardiology Department between 2003 and 2005. 22q11.2 microdeletion was identified by fluorescence in situ hybridization. The postoperative course following cardiac surgery was compared in patients with TOF and its more severe form, PA-VSD, with/without del22q11.2 (groups A and B) and TAC with/without del22q11.2 (groups C and D). In 15 of 214 patients, 22q11.2 microdeletion was diagnosed (in 11 with TOF/PA-VSD, in three with TAC, in one with IAA type B). In patients with TOF/PA-VSD and microdeletion anatomic features that were significantly associated with 22q11.2, deletion included right aortic arch (p = 0.018), aberrant right subclavian artery (p < 0.001), and major aortopulmonary collateral arteries (p = 0.016). A complicated postoperative course was more frequent and mortality was higher in patients with conotruncal defects and with/without microdeletion. We conclude that additional cardiovascular anomalies are significantly more frequent in children with 22q11.2 microdeletion and TOF/PA-VSD. Children with conotruncal heart defects and 22q11.2 microdeletion more frequently experienced complicated postoperative course after cardiac surgery.

Evolving approach to aortic valve replacement in children and adolescents--a preliminary report.

BACKGROUND: Surgical treatment methods are still controversial in children with congenital or acquired aortic valve dysfunction. AIM: To evaluate treatment results in children after mechanical or biological valve implantation. METHODS: We analysed a group of 55 children after mechanical valve implantation (group A) and a group of 8 children after Freestyle biological valve implantation (group B). We evaluated in both groups: patient's age, type of valve dysfunctions, severity of heart failure symptoms, and quality of life. The parameters of physiological left ventricular (LV) remodelling were examined on the basis of echocardiographical signs of LV contractibility (%SF) and anatomical changes: LV diastolic diameter (LVDd), LV posterior wall thickness (LVPW), thickness of intra-ventricle septum (IVS) and pressure gradient between LV and aorta (LV-Ao). RESULTS: There were no hospital deaths in either group. There were two late deaths in children from group A. Thromboembolic (2), nonspecific bleeding complications (2), and infections (2) occurred in group A. There were two re-operations in children after mechanical valve implantation. The early postoperative period was good in groups A and B. Furthermore, late postoperative period was good in group B. Physiological LV remodelling occurred in children in groups A and B. Quality of life was good in both groups. CONCLUSIONS: Good clinical results, simplicity, repeatability and safety of surgical technique mean that mechanical valve implantation in the aortic position is still an attractive option for treatment in children and adults. However, absence of bleeding, thromboembolic and infection complications and improvement of durability mean that the Freestyle biological new generation valve could be a good option for future in children and adolescents who need aortic valve replacement.

Risk factors for cardiac arrhythmias in children with congenital heart disease after surgical intervention in the early postoperative period.

OBJECTIVE: Early postoperative arrhythmias are a recognized complication of pediatric cardiac surgery. METHODS: Diagnosis and treatment of early postoperative arrhythmias were prospectively analyzed in 402 consecutive patients aged 1 day to 18 years (mean 29.5 months) who underwent operation between January and December 2005 at our institute. All children were admitted to the intensive care unit, and continuous electrocardiogram monitoring was performed. Risk factors, such as age, weight, Aristotle Basic Score, cardiopulmonary bypass time, aortic crossclamp time, and use of deep hypothermia and circulatory arrest, were compared. Statistical analysis using the Student t test, Mann-Whitney U test, or Fisher exact test was performed. Multivariate stepwise logistic regression was used to assess the risk factors of postoperative arrhythmias. RESULTS: Arrhythmias occurred in 57 of 402 patients (14.2%). The most common types of arrhythmia were junctional ectopic tachycardia (21), supraventricular tachycardia (15), and arteriovenous block (6). Risk factors for arrhythmias, such as lower age (P = .0041*), lower body weight (P = .000001*), higher Aristotle Basic Score (P = .000001*), longer cardiopulmonary bypass time (P = .000001*), aortic crossclamp time (P = .000001*), and use of deep hypothermia and circulatory arrest (P = .0188*), were identified in a univariate analysis. In the multivariate stepwise logistic regression, only higher Aristotle Basic Score was statistically significant (P = .000003*) compared with weight (P = .62) and age (P = .40); in the cardiopulmonary bypass group, only longer aortic crossclamp time was statistically significant (P = .007*). CONCLUSION: Lower age, lower body weight, higher Aristotle Basic Score, longer cardiopulmonary bypass time, aortic crossclamp time, and use of deep hypothermia and circulatory arrest are the risk factors for postoperative arrhythmias. Junctional ectopic tachycardia and supraventricular tachycardia were the most common postoperative arrhythmias.