233 research outputs found
Realignment of the ventricular septum using partial direct closure of the ventricular septal defect in Tetralogy of Fallot
Objective: The aim is to describe our technique of partial direct closure of the ventricular septal defect (VSD) in Tetralogy of Fallot (TOF), and assess its influence on the realignment and remodeling of the left ventricular outflow tract. Methods: Between 2004 and 2010, 32 non-consecutive patients with TOF underwent a direct or partial direct closure of VSD. Median age and weight were 5.2 months and 6.7kg, respectively. An approach through the right atrium was used in 30 patients and through the infundibulum in two patients. The conal septum was mobilized by transecting the hypertrophic trabeculae to facilitate the approximation of the VSD. The membranous part of the VSD was closed (in the later part of the series) with a small xenopericardial patch to avoid tension on the suture line traversing the area of risk to the bundle of His. Follow-up was complete, with a median duration of 46.9 (range 12-75.3) months. Results: The VSD could be closed successfully in all patients. A residual VSD was partly responsible for one early postoperative re-operation. There were no early or late deaths. At follow-up, all patients were in sinus rhythm. Three patients showed a small residual VSD. Thirty patients had none, one showed trivial, and one had mild aortic regurgitation. The left ventricular outflow showed a good realignment of the ventricular septum in all the patients. Conclusions: Partial direct closure of the VSD corrects the primary defect in TOF, that is, the malalignment of the septum. It results in a straight, wide open left ventricular outflow tract and brings better support to the aortic roo
Remodelling of the right ventricle after early pulmonary valve replacement in children with repaired tetralogy of Fallot: assessment by cardiovascular magnetic resonance
Aims Correct timing of pulmonary valve replacement (PVR) is crucial for preventing complications of pulmonary regurgitation and right ventricular (RV) dilatation after repair of tetralogy of Fallot. We sought to assess the remodelling of the RV after early PVR in children, using cardiovascular magnetic resonance (CMR). Methods and results Twenty children with severe pulmonary regurgitation and RV dilatation and mean age 13.9±3 years underwent CMR evaluation 5.6±1.8 months before and 5.9±0.6 months after PVR. PVR was performed when the RV end-diastolic volume exceeded 150 mL/m2, as measured by CMR. The time interval between primary repair and PVR was 12±3 years. Post-operative CMR demonstrated a significant reduction of the RV end-diastolic volume from 189.8±33.4 to 108.7±25.8 mL/m2 (P<0.0001), of the RV end-systolic volume from 102.4±27.3 to 58.2±16.3 mL/m2 (P<0.0001), and of the RV mass from 48.7±12.3 to 35.8±7.7 g/m2 (P<0.0001). The RV ejection fraction did not change significantly. Conclusion Prompt RV remodelling, with reduction of RV volume and mass, is observed after performing PVR if the RV end-diastolic volume exceeds 150 mL/m2. Early PVR may prevent the detrimental complications of severe pulmonary regurgitatio
Management and outcome of Ebstein's anomaly in children
Abstract Objectives To assess clinical presentation, treatment, and outcome of children with Ebstein's anomaly. Background Data on long-term outcome of children with Ebstein's anomaly are scarce. Methods Retrospective analysis of all children with Ebstein's anomaly treated between February, 1979 and January, 2009 in a single tertiary institution. Primary outcomes included patient survival and need for intervention, either cardiac surgery or catheter intervention. Results A total of 42 patients were diagnosed with Ebstein's anomaly at a median age of 5 days ranging from 1 day to 11.7 years. Symptoms included cyanosis, heart murmur, and/or dyspnoea. Associated cardiac anomalies occurred in 90% of the patients. Average follow-up was 9.5 plus or minus 7.0 years. The overall mortality rate was 14%. Of the six patients, three died postnatally before treatment. Cardiac surgery and/or catheter-guided interventions were required in 33 patients (79%). Cardiac surgery was performed in 21 (50%) patients at a median age of 9.1 years (range 0.1-16.5 years), including biventricular repair in 13 (62%), one-and-a-half chamber repair in seven (33%), and a staged single-ventricle repair in one. Peri-operative mortality was 4%. Catheter-guided interventions consisted of device closure of an atrial septal defect in three cases and radiofrequency ablation of accessory pathways in nine patients. The estimated 10-year survival was 85.3 plus or minus 5.6%. Conclusion In children, Ebstein's anomaly is usually diagnosed in the first year of age. Even though children with Ebstein's anomaly often require an intervention, their peri-operative mortality is low and long-term survival is good. Symptomatic newborns requiring an intervention may have a worse outcom
Sinus node disease and arrhythmias in the long-term follow-up of former professional cyclists
Aims Significant brady- and tachyarrhythmias may occur in active endurance athletes. It is controversial whether these arrhythmias do persist after cessation of competitive endurance training. Methods and results Among all 134 former Swiss professional cyclists [hereafter, former athletes (FAs)] participating at least once in the professional bicycle race Tour de Suisse in 1955-1975, 62 (46%) were recruited for the study. The control group consisted of 62 male golfers matched for age, weight, hypertension, and cardiac medication. All participants were screened with history, clinical and echocardiographic examination, ECG, and 24 h ECG. The time for the last bicycle race of FAs was 38 ± 6 years. The mean age at examination was 66 ± 6 years in controls and 66 ± 7 years in FAs (P = 0.47). The percentage of study participants with >4 h current cardiovascular training per week was identical. QRS duration (102 ± 20 vs. 95 ± 13 ms, P = 0.03) and corrected QTc interval (416 ± 27 vs. 404 ± 18, P = 0.004) were longer in FAs. There was no significant difference in the number of isolated atrial or ventricular premature complexes, or supraventricular tachycardias in the 24 h ECG; however, ventricular tachycardias tended to occur more often in FAs than in controls (15 vs. 3%, P = 0.05). The average heart rate was lower in FAs (66 ± 9 vs. 70 ± 8 b.p.m.) (P = 0.004). Paroxysmal or persistent atrial fibrillation or flutter was reported more often in FAs (P = 0.028). Sinus node disease (SND), defined as bradycardia of 2.5 s (6 vs. 0%), was more common in FA (16%) than in controls (2%, P = 0.006). Observed survival of all FAs was not different from the expected. Conclusions Among FAs, SND occurred significantly more often compared with age-matched controls, and there is trend towards more frequent ventricular tachycardias. Further studies have to evaluate prevention of arrhythmias with extreme endurance training, the necessity of regular follow-up of heart rhythm, and management of arrhythmias in former competitive endurance athlete
Double left ventricular pacing following accidental malpositioning of the right ventricular electrode during implantation of a cardiac resynchronization therapy device
Accidental malpositioning of a right ventricular (RV) electrode has not been previously reported in the context of cardiac resynchronization therapy (CRT). The case of a 75-year old male patient with dilative cardiomyopathy, left ventricular (LV) ejection fraction 23%, New York Heart Association functional heart failure status stage III, left bundle branch block (LBBB) with QRS width of 136Â ms, and misplacement of the RV lead to the LV apex during implantation of a CRT defibrillator is described. Following unremarkable implantation, routine interrogation of the CRT device on the first day after the implantation revealed uneventful technical findings. The 12-lead surface electrocardiogram (ECG) showed biventricular stimulation featuring a narrow QRS complex with incomplete right bundle branch block (RBBB) and R>S in V1. The biplane postoperative chest X-ray was graded normal. On routine follow-up one month later, a transthoracic echocardiogram revealed an increased ejection fraction of 51% but the RV lead was placed in the LV apex. An additional transesophageal echocardiogram exhibited an Eustachian valve guiding the lead via the patent foramen ovale through the mitral valve into the LV apex. Operative revision was scheduled and the active fixation lead was uneventful removed from the LV. A new electrode was inserted and placed in the RV apex. Accidental malplacement of the RV electrode to the LV may be difficult to diagnose in the context of CRT patients as a stimulated biventricular ECG with incomplete RBBB appearance is expected in this situation. Careful analysis of lateral radiographic views during the operation is important to ensure correct lead positioning. As timely revision is the preferred procedure, early routine transthoracic echocardiography may be considered for detection of malplacement
Feasibility of perfusion cardiovascular magnetic resonance in paediatric patients
AIMS: As coronary artery disease may also occur during childhood in some specific conditions, we sought to assess the feasibility and accuracy of perfusion cardiovascular magnetic resonance (CMR) in paediatric patients. METHODS AND RESULTS: First-pass perfusion CMR studies were performed under pharmacological stress with adenosine and by using a hybrid echo-planar pulse sequence with slice-selective saturation recovery preparation. Fifty-six perfusion CMR examinations were performed in 47 patients. The median age was 12 years (1 month-18 years), and weight 42.8 kg (2.6-82 kg). General anaesthesia was required in 18 patients. Mean examination time was 67 +/- 19 min. Diagnostic image quality was obtained in 54/56 examinations. In 23 cases the acquisition parameters were adapted to patient's size. Perfusion CMR was abnormal in 16 examinations. The perfusion defects affected the territory of the left anterior descending coronary artery in 11, of the right coronary artery in 3, and of the circumflex coronary artery in 2 cases. Compared to coronary angiography, perfusion CMR showed a sensitivity of 87% (CI 52-97%) and a specificity of 95% (CI 79-99%). CONCLUSION: In children, perfusion CMR is feasible and accurate. In very young children (less than 1 year old), diagnostic image quality may be limited
The fate of children with microdeletion 22q11.2 syndrome and congenital heart defect: clinical course and cardiac outcome
BACKGROUND: This study aimed to evaluate the cardiac outcome for children with microdeletion 22q11.2 and congenital heart defect (CHD). METHODS: A total of 49 consecutive children with 22q11.2 and CHD were retrospectively identified. The CHD consisted of tetralogy of Fallot and variances (n = 22), interrupted aortic arch (n = 10), ventricular septal defect (n = 8), truncus arteriosus (n = 6), and double aortic arch (n = 1). Extracardiac anomalies were present in 46 of 47 children. RESULTS: The median follow-up time was 8.5 years (range, 3 months to 23.5 years). Cardiac surgical repair was performed for 35 children, whereas 5 had palliative surgery, and 9 never underwent cardiac surgery. The median age at repair was 7.5 months (range, 2 days to 5 years). The mean hospital stay was 35 days (range, 7-204 days), and the intensive care unit stay was 15 days (range, 3-194 days). Significant postoperative complications occurred for 26 children (74%), and surgery for extracardiac malformations was required for 21 patients (43%). The overall mortality rate was 22% (11/49), with 1-year survival for 86% and 5-year survival for 80% of the patients. A total of 27 cardiac reinterventions were performed for 16 patients (46%) including 15 reoperations and 12 interventional catheterizations. Residual cardiac findings were present in 25 patients (71%) at the end of the follow-up period. CONCLUSIONS: Children with microdeletion 22q11.2 and CHD are at high risk for mortality and morbidity, as determined by both the severity of the cardiac lesions and the extracardiac anomalies associated with the microdeletion
The phenomenology of the mathematics classroom
This paper describes the mathematics classroom from the perspective of social phenomenology. Here the classroom is seen as an environment of signs, comprising things and people, which impinge on the reality of the individual child. The paper introduces a framework through which mathematical work is seen as taking place in the imagined world through the filter of the world in immediate perception. This provides an approach to structuring evolving mathematical understanding. It is suggested that mathematical ideas are contained and shaped by the child's personal phenomenology, which evolves through time. Further, I argue these ideas are never encountered directly but rather are met through a circular hermeneutic process of reconciling expectation with experience. © 1996 Kluwer Academic Publishers
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