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Ralf Rauch

Publications and source records attributed to Ralf Rauch.

9 recordsLinked to original sources

Prophylaxis of thromboembolic complications after the Fontan operation (total cavopulmonary anastomosis).

OBJECTIVES: Thrombotic events have been reported as a major cause of morbidity after the Fontan procedure. There is no consensus concerning the postoperative mode and duration of anticoagulation prophylaxis. In a retrospective study, we evaluated the results of a prophylactic regimen on the basis of the surgical technique, potentially predisposing risk factors, and specific sequelae. METHODS: We evaluated 142 surviving patients after total cavopulmonary anastomosis (mean follow-up was 91.1 +/- 43.9 months). Prophylactic antithrombotic treatment was initiated in 86 patients with partial prosthetic venous pathway with acetylsalicylic acid; 45 patients with complete autologous tissue venous pathway or partial prosthetic venous pathway received no anticoagulation, and 11 patients received warfarin sodium (Coumadin). During long-term follow-up, 22 patients (12 after acetylsalicylic acid medication) crossed over to warfarin. RESULTS: Thrombotic events occurred in 10 patients (7%), with systemic venous thrombus formation in 8 (5.6%), stroke in 2 (1.4%), and a peak incidence during the first postoperative year. Eight of 10 patients were receiving heparin therapy mainly for prolonged postoperative immobilization. During follow-up, none of the 74 patients receiving acetylsalicylic acid and 1 of 40 patients without medication presented with thrombus formation. Under warfarin medication, 1 of 28 patients had an asymptomatic thrombus. Expected freedom from a thromboembolic event was 92% at 5 years and 79% at 10 years. There was no association with coagulation factor abnormalities. Protein-losing enteropathy was present in 4 of 10 patients. CONCLUSION: A prophylactic anticoagulation strategy that considers the surgical technique and potential predisposing circumstances proved effective in the prevention of late thrombotic complications after total cavopulmonary anastomosis. There is no need for routine anticoagulation during long-term follow-up after Fontan-type surgery in pediatric patients.

Anticoagulants↗

Laterality of the aortic arch and anomalies of the subclavian artery-reliable indicators for 22q11.2 deletion syndromes?

UNLABELLED: A variety of cardiac defects, encompassing truncus arteriosus, tetralogy of Fallot, pulmonary atresia with ventricular septal defect and interrupted aortic arch, are generally summarised as conotruncal malformations. Patients with these cardiac defects were frequently found to have a common microdeletion on chromosome 22, the so-called monosomy 22q11.2. The aim of our study was to determine whether the laterality of the aortic arch or the presence of subclavian artery anomalies (SAA) represent markers for monosomy 22q11.2 in these patients. 170 patients with these cardiac anomalies were recruited at presentation in the paediatric cardiology units of two tertiary referral centres from 1994 until 2003. Of the 170 children and young adults, 33 had interrupted aortic arch, 35 tetralogy of Fallot, 31 truncus arteriosus communis and 71 pulmonary atresia with ventricular septal defect. All were screened for monosomy 22q11.2 and the results were correlated with the laterality of the aortic arch and the presence of SAA contralateral to the aortic arch (aberrant origin from the descending aorta, isolation, distal ductal origin from the pulmonary artery and cervical origin of the right subclavian artery). Monosomy 22q11.2 was present in 59/170 patients (35%). A left aortic arch (LAA) was found in 118 (69%), a right aortic arch (RAA) in 52 (31%) patients. Almost 50% of the patients with RAA (46%), but only 30% of the patients with LAA had monosomy 22q11.2 ( P=0.054). A total of 47 patients (28%) had an anomaly of the subclavian artery, 81% of whom had monosomy 22q11.2. This deletion was found in decreasing percentage in patients with LAA+SAA (85%) >RAA+SAA (75%) >RAA without SAA (28%) >LAA without SAA (13%). CONCLUSION: In patients with conotruncal malformations, anomalies of the subclavian arteries are the most important anatomical marker for the presence of monosomy 22q11.2, independent of the laterality of the aortic arch. Therefore, we recommend cytogenetic testing for this microdeletion in all patients with subclavian artery anomalies and conotruncal malformations.

Adolescent↗

Search for somatic 22q11.2 deletions in patients with conotruncal heart defects.

A wide range of clinical variability in patients with 22q11.2 deletions has been demonstrated in numerous studies. Nevertheless, it is still an open question if major genetic factors contribute to clinical expression. Therefore one aim of this study was to investigate, if patients with 22q11.2 deletion and conotruncal heart defects show a "second hit" somatic 22q11.2 deletion in tissue from the conotruncus, heart vessels or thymus. The second aim was to analyse patients with conotruncal heart defects without 22q11.2 deletion in blood cells for somatic deletion mosaicism. We were able to study tissue samples from heart surgery from 23 patients, 9 of whom had 22q11 deletions by FISH analysis on metaphase spreads from peripheral lymphocytes. Analysis of 18 polymorphic markers from the 22q11.2 region in DNA prepared from thymus and/or heart vessels and/or conotruncus tissue and peripheral lymphocytes in each patient did not show any allelic loss. Thus somatic 22q11.2 deletions apparently do not play a major role in conotruncal heart defects in patients with or without germ line 22q11.2 deletion.

Child↗

Genotype-phenotype correlations in Noonan syndrome.

OBJECTIVE: To study genotype-phenotype correlations in a cohort of clinically well-characterized pediatric patients with Noonan syndrome (NS). Study design Fifty-seven unrelated patients with the clinical diagnosis of NS ascertained according to standardized inclusion criteria were prospectively enrolled. Mutational analysis was performed by direct sequencing of the entire coding sequence of the PTPN11 gene. RESULTS: Sixteen known and 3 novel PTPN11 mutations could be detected in 60% of index patients, in all familial and in 52% of the sporadic cases. Presence of pulmonic stenosis, short stature, easy bruising, and thorax deformities was significantly associated with a PTPN11 mutation, whereas cardiomyopathy was more common in patients without a mutation. On average, PTPN11 mutation-negative probands fulfilled fewer clinical criteria of NS, but more than half-among them all with cardiomyopathy-had the full clinical picture of NS indistinguishable from typical cases with PTPN11 mutation. CONCLUSIONS: The phenotype of NS due to PTPN11 mutations is clinically unambiguous in the majority of patients and represents a highly penetrant trait. Individuals with the clinical diagnosis of NS but without a PTPN11 mutation presumably represent a heterogeneous group in which patients with cardiomyopathy appear to constitute an interesting subgroup for future research.

Adolescent↗

Hypoparathyroidism in conotruncal heart defects.

UNLABELLED: This retrospective study was designed to evaluate serum levels of intact parathyroid hormone and calcium in patients with conotruncal heart defects with or without microdeletion 22q11.2 in order to investigate a correlation between various types of conotruncal heart defect and hypoparathyroidism. A total of 67 patients with truncus arteriosus, tetralogy of Fallot, pulmonary atresia and ventricular septal defect, interrupted aortic arch or vascular ring were included of whom 28 had a 22q11.2 deletion (Group I) and 39 did not (Group II). In two patients of Group I and in one patient of Group II, parathyroid hormone level was decreased with normal serum calcium levels. No patient of Group II showed hypocalcaemia. In Group I, complete hypoparathyroidism with low parathyroid hormone and hypocalcaemia occurred in seven patients; 5 patients had bilateral anomalies of the right and the left 4th aortic arch derivates. In addition to an interrupted aortic arch type B or a high aortic arch, the contralateral subclavian artery arose cervically, high thoracically or anomalously from the descending aorta. Two patients had unilateral anomalies of the 4th aortic arch system: The origin of the right subclavian artery was cervical or from the descending aorta. CONCLUSION: Hypoparathyroidism occurred in 7 of our 28 patients with conotruncal heart defect and monosomy 22q11.2 and was associated with an extended regression of the 4th aortic arch development on both sides of the aortic arch system.

Adolescent↗