Short-term renal support in postoperative repair of tetralogy of Fallot in the paediatric intensive care unit: can we predict those who need it?

INTRODUCTION: Fluid balance and renal function can be difficult to manage in the postoperative infant with tetralogy of Fallot. High fluid volumes are often needed to maintain cardiac output. Aims To stratify patients at risk for advanced renal support following tetralogy of Fallot repair. METHODS: Retrospective analysis of all consecutive tetralogy of Fallot cases operated at a single centre in a 3-year period. RESULTS: A total of 41 children were identified. All cases had loop diuretics administered. Of the cases, 17% required support with a peritoneal dialysis catheter, with only one complication of peritoneal dialysis catheter blockage. The mean length of paediatric intensive care unit stay in those receiving peritoneal dialysis catheter insertion was prolonged by an additional mean of 6 days (p<0.001). No statistical significance was found between those children requiring peritoneal dialysis and those who did not when considering patient age and weight at time of repair, cardiopulmonary bypass and aortic cross clamp times, the presence of a transannular patch, or junctional ectopic tachycardia. However, volume requirement of more than 35 ml/kg in the first 12 hours following repair did increase the likelihood to need peritoneal dialysis (p<0.0001). Furthermore, the higher the peak creatinine, the longer the stay on intensive care (p<0.01). CONCLUSIONS: Peritoneal dialysis is an effective method of dealing with fluid balance in children after tetralogy of Fallot repair, with minimal complications. Early consideration should be given to peritoneal dialysis when it is clear that high fluid volumes are required postoperatively.

Implantable cardioverter defibrillator therapy in paediatric practice: a single-centre UK experience with focus on subcutaneous defibrillation.

AIMS: Sudden cardiac death (SCD) risk can be managed by implantable cardioverter defibrillators (ICD). Defibrillation shocks can be delivered via ICD generator and/or intracardiac or subcutaneous coil configurations. We present our single-centre use of childhood ICDs. METHODS AND RESULTS: Twenty-three patients had ICD implantation, with median age and weight of 12.96 years and 41.35 kg. Indications included eight long QT; four hypertrophic cardiomyopathy; three Brugada syndrome; two idiopathic ventricular fibrillation; two post-congenital heart repair; two family history of SCD with abnormal repolarization; one catecholaminergic polymorphic ventricular tachycardia; and one left ventricle non-compaction. Twelve had out of hospital cardiac arrests prior to implantation. Techniques included 13 conventional ICD implants (pre-pectoral device with endocardial leads), 7 with subcutaneous defibrillation coils (sensing via epicardial or endocardial leads tunnelled to the ICD), and 3 with exclusive subcutaneous ICD (sensing and defibrillation via the same subcutaneous lead). Satisfactory defibrillation efficacy and ventricular arrhythmia sensing was confirmed at implantation. Follow-up ranged from 0.17 to 11.08 years. One child died with the ICD in situ. Ten children received appropriate shocks; five on more than one occasion. Five received inappropriate shocks (for inappropriate recognition of sinus tachycardia or supraventricular tachycardia). Five children underwent six further interventions; all had intracardiac leads. CONCLUSION: Innovative shock delivery systems can be used in children requiring an ICD. The insertion technique and device used need to accommodate the age and weight of the child, and concomitant need for pacing therapy. We have demonstrated effective defibrillation with shocks delivered via configurations employing subcutaneous coils in children.

Acquired stenosis of normally connected pulmonary veins.

Pulmonary venous stenosis has been a challenge to paediatric cardiologists and surgeons. In spite of significant improvements in the management and outcome of various congenital cardiac problems, the prognosis of this condition continues to be dismal. Acquired stenosis of the pulmonary veins has been described in the adult population, especially after radiofrequency ablation for atrial arrhythmias. The outcome of this condition has generally been described to be favourable in the long term. Acquisition of pulmonary venous stenosis in childhood has a very different outcome, and is not a very well recognised entity, with symptoms and signs which are non-specific. We present 7 infants who, when first assessed, had normal pulmonary veins, but who subsequently acquired stenoses of the veins, with very significant resultant morbidity and mortality.

Correlations with operative anatomy of real time three-dimensional echocardiographic imaging of congenital aortic valvar stenosis.

OBJECTIVE: To define the anatomic characteristics of the congenitally malformed and severely stenotic aortic valve using trans-thoracic real time three-dimensional echocardiography, and to compare and contrast this with the valvar morphology as seen at surgery. DESIGN: Prospective cross-sectional observational study. SETTING: Tertiary centre for paediatric cardiology. METHODS: All patients requiring aortic valvotomy between December 2003 and July 2004 were evaluated prior to surgery with three-dimensional echocardiography. Full volume loop images were acquired using the Phillips Sonos 7500 system. A single observer analysed the images using "Q lab 4.1" software. The details were then compared with operative findings. RESULTS: We identified 8 consecutive patients, with a median age of 16 weeks, ranging from 1 day to 11 years, with median weight of 7.22 kilograms, ranging from 2.78 to 22 kilograms. The measured diameter of the valvar orifice, and the number of leaflets identified, corresponded closely with surgical assessment. The sites of fusion of the leaflets were correctly identified by the echocardiographic imaging in all cases. Fusion between the right and non-coronary leaflets was identified in half the patients. Dysplasia was observed in 3 patients, with 1 patient having nodules and 2 shown to have excrescences. At surgery, nodules were excised, and excrescences were trimmed. The dysplastic changes correlated well with operative findings, though statistically not significant. CONCLUSION: We recommend trans-thoracic real time three-dimensional echocardiography for the assessment of the congenitally malformed aortic valve, particularly to identify sites of fusion between leaflets and to measure the orificial diameter. The definition of nodularity, and the prognosis of nodules based on the mode of intervention, will need a comparative study of patients submitted to balloon dilation as well as those undergoing surgical valvotomy.

Annuloplasty of the regurgitant mitral valve after myocarditis in children.

Acute myocarditis is characterized by the development of rapid life-threatening congestive heart failure and arrhythmias. In many cases with hemodynamic compromise, medical therapy and mechanical support alone are not sufficient. Various surgical procedures have been tried to bridge patients with myocarditis to both transplant and recovery. Mitral regurgitation is a frequent association with end stage cardiomyopathy and predicts poor outcome. Mitral annuloplasty is well-established in adults with ischemic and dilated cardiomyopathy and the results are superior to medical therapy alone and are comparable to cardiac transplantation. However, its effectiveness and use is not well-established in children with cardiomyopathy. We report our experience in two children.

Quality of life after repair of tetralogy of Fallot.

OBJECTIVE: To determine the quality of life in individuals with corrected tetralogy of Fallot. METHODS AND SUBJECTS: Questionnaires concerning quality of life were sent to all 87 surviving patients aged between 16 and 40 years who had undergone intracardiac repair of tetralogy of Fallot and follow-up in the Wessex Cardiothoracic Unit, and to 87 age and sex matched controls, with medically treated haemodynamically insignificant ventricular septal defects. RESULTS: The only significant difference found between the cases and controls was in requirements for schooling, where those with tetralogy of Fallot were more likely to require additional educational help at school (p = 0.044). For all other aspects of quality of life examined by the questionnaire, including social and genetic history, exercise ability, and health related quality of life, no significant differences were found. Different operative techniques, such as transjunctional patching, right ventriculotomy, and previous palliative shunting, did not affect the quality of life of our population with Tetralogy of Fallot, on average twenty years after their surgery, although the range of operative techniques was limited. Neither age at surgery, nor time since surgery, was correlated with measurements of quality of life. CONCLUSIONS: Those who have undergone surgical correction of tetralogy of Fallot have a normal quality of life, with few differences compared to controls.