Dirk A. Redel
University of Bonn
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Featured researches published by Dirk A. Redel.
Journal of Perinatal Medicine | 1988
U. Gembruch; M. Hansmann; Dirk A. Redel; Rainer Bald
In cases of fetal tachyarrhythmia with congestive heart failure accompanied by signs of non-immune hydrops fetalis, the transplacental treatment of the fetus with antiarrhythmic agents by administration of drugs to the mother is only rarely successful. In the two cases reported, the cardioversion of a supraventricular tachycardia to a sinus rhythm or a constant 2:1 AV conduction block to a 1:1 AV conduction with atrial flutter could only be achieved after additional antiarrhythmic treatment directly administered to the fetus using ultrasound guidance. Drugs used include: beta-methyldigoxin, verapamil, propafenon, and they were administered according to the dosing amounts for intravascular injections. This was carried out 12 times in case 1 by the intraperitoneal route into the fetal ascites and twice in case 2. This led in both cases to varying durations of a sustained sinus rhythm after 5-15 minutes. This technically relatively simple procedure affords the option of rapidly achieving high concentrations, even when antiarrhythmic agents are administered which do not adequately cross the placenta. This direct treatment is indicated in cases of tachyarrhythmia with advanced signs of non-immune hydrops fetalis as a supplement to the high-dose transplacental therapy using antiarrhythmic agents.
American Heart Journal | 1991
U. Gembruch; G. Knöpfle; Molly Chatteriee; Rainer Bald; Dirk A. Redel; Hans-Jörg Födisch; M. Hansmann
Fourteen fetuses with atrioventricular canal malformations were examined by two-dimensional echocardiography, pulsed-wave Doppler echocardiography, and color Doppler flow mapping. Eleven fetuses had complete and three fetuses had partial atrioventricular canal malformations. Nonimmune hydrops fetalis was associated with six cases, and fetal arrhythmia was seen in three cases. With two-dimensional echocardiography, the atrioventricular canal malformations could be diagnosed accurately. The inclusion of color Doppler flow mapping, however, provided additional hemodynamic information that was important from the prognostic point of view. Incompetence of atrioventricular valves could be demonstrated in 10 of 14 cases by Doppler echocardiography. In nine cases, detailed Doppler echocardiographic evaluation of the regurgitation jet was possible. The proportion of systolic time during which atrioventricular valve insufficiency was demonstrated was related to the occurrence of nonimmune hydrops fetalis. When insufficiency of atrioventricular valves was associated with hydrops (four cases), a pansystolic insufficiency was always present. In cases without hydrops (five), regurgitation was confined to early systole. Thus a reliable method for semiquantitative evaluation of the degree of insufficiency seems to have been found. Moreover, an association appeared to exist between the occurrence of hydrops fetalis and the proportion of atrial area that was taken up by regurgitant jet area, as determined by planimetry in the four-chamber view. Prenatal diagnosis was confirmed by autopsy or neonatal cardiac evaluation. Only one neonate survived in our series. Two were stillborn, four died during the neonatal period, two died during infancy, and pregnancy was electively terminated prematurely in five cases. Eight fetuses were found to have a karyotypic abnormality.
Journal of Perinatal Medicine | 1991
U. Gembruch; Chatterjee Ms; Rainer Bald; Dirk A. Redel; M. Hansmann
Color Doppler flow mapping of fetal heart was performed in 582 fetuses between 16 and 38 weeks of gestation. Congenital heart diseases were excluded in 522 fetuses correctly. In 59 fetuses structural and/or functional cardiac abnormalities were diagnosed. In one fetus small multiple ventricular septal defects were missed. The most important additional information obtained by color Doppler flow mapping was: (1) Diagnosis of insufficiencies of atrioventricular valves; (2) Demonstration of turbulent high velocity jet in stenosis of semilunar valve; (3) Reverse flow in ascending aorta in atresia of aortic valves and on ductus arteriosus and main pulmonary artery in atresia of pulmonary valves; (4) Reverse perfusion of ductus arteriosus and main pulmonary artery as well as an antegrade turbulent high velocity jet in severe pulmonary stenosis as part of tetralogy of Fallot; (5) Bidirectional interventricular shunting of blood in ventricular septal defect. Color Doppler flow mapping allows rapid screening for flow abnormalities of the fetal heart. Exact localisation of sample volume by pulsed wave Doppler in area of abnormal flow pattern is possible, thus significantly reducing the Doppler examination time. The accuracy of prenatal diagnosis of congenital heart diseases is improved by application of color Doppler flow mapping, in particular in presence of complex cardiac defects.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1990
U. Gembruch; Zwi Weinraub; Rainer Bald; Dirk A. Redel; G. Knöpfle; M. Hansmann
Prenatal diagnosis of tetralogy of Fallot by two-dimensional echocardiography, which is based on demonstration of a ventricular septal defect and a large overriding aorta, is difficult. In the majority of cases the main pulmonary artery is small. In utero, there is no pathologically increased degree of the physiological right-ventricular hypertrophy. Colour Doppler flow mapping of reverse flow from the descending aorta via the ductus arteriosus into the main pulmonary artery is easily demonstrated, and provides an indirect sign of severe right-ventricular outlet obstruction. The technique also differentiates between pulmonary stenosis and atresia; the stenotic jet, even small, is identified by demonstration of high velocities and turbulences in the main pulmonary artery.
Archive | 1993
U. Gembruch; Rainer Bald; Dirk A. Redel; Matthias Manz; M. Hansmann
Fetal arrhythmia is usually first suspected through ausculatory or cardiotocographic findings. The clinical importance of fetal arrhythmia may vary from cases which are benign and self-limited to those that are sustained and associated with fetal congestive heart failure, hydrops and/or death.
Archive | 1991
U. Gembruch; Dirk A. Redel; M. Hansmann
Zwischen 1987 bis April 1989 untersuchten wir 1488 Feten Farbdoppler-echokardiographisch. Bei 102 dieser Feten lag ein angeborener Herzfehler vor. Bei 29 von ihnen konnte pranatal ein Ventrikelseptumdefekt (VSD) nachgewiesen werden. Feten mit AV-Kanal-Defekten wurden wegen ihrer besonderen Anatomie (funktionell gemeinsamer Einflustrakt beider Ventrikel) in dieser Studie nicht berucksichtigt.
Archives of Gynecology and Obstetrics | 1989
U. Gembruch; M. Hansmann; Dirk A. Redel; Rainer Bald
The fetuses of 352 patients at between 16 and 38 weeks of gestation were studied by using two-dimensional Doppler echocardiography (2-DDE). In 32 fetuses, structural and/or functional abnormalities were detected. The advantages of 2-DDE are, in particular, rapid screening for flow abnormalities and, thus, shortening of the Doppler examination time. Further benefits include a rapid diagnosis of valvular regurgitation, valvular stenosis, and abnormal shunting of blood across the cardiac septa. The diagnosis of complex heart defects is facilitated by and, in certain cases, only possible at all using 2-DDE.SummaryThe fetuses of 352 patients at between 16 and 38 weeks of gestation were studied by using two-dimensional Doppler echocardiography (2-DDE). In 32 fetuses, structural and/or functional abnormalities were detected. The advantages of 2-DDE are, in particular, rapid screening for flow abnormalities and, thus, shortening of the Doppler examination time. Further benefits include a rapid diagnosis of valvular regurgitation, valvular stenosis, and abnormal shunting of blood across the cardiac septa. The diagnosis of complex heart defects is facilitated by and, in certain cases, only possible at all using 2-DDE.ZusammenfassungZwischen der 17. und 39. Schwangerschaftswoche wurden 352 Patientinnen mittles der fetalen zweidimensionalen Doppler-Echokardiographie (2-DDE) untersucht. Bei 32 Feten wurden strukturelle und/oder funktionelle Anomalien nachgewiesen. Die Vorteile der 2-DDE waren: schnelles screening nach Flußanomalien und somit beträchtliche Verkürzung der Untersuchungszeit der Doppler-Echokardiographie; rasche Diagnose valvulärer Insuffizienzen und Stenosen sowie interventrikulärer Shunts. So ist die Diagnose komplexer kardialer Fehlbildungen erleichtert und in einzelnen Fällen erst durch die 2-DDE möglich.
Archives of Gynecology and Obstetrics | 1989
U. Gembruch; M. Hansmann; Dirk A. Redel; Rainer Bald
The fetuses of 352 patients at between 16 and 38 weeks of gestation were studied by using two-dimensional Doppler echocardiography (2-DDE). In 32 fetuses, structural and/or functional abnormalities were detected. The advantages of 2-DDE are, in particular, rapid screening for flow abnormalities and, thus, shortening of the Doppler examination time. Further benefits include a rapid diagnosis of valvular regurgitation, valvular stenosis, and abnormal shunting of blood across the cardiac septa. The diagnosis of complex heart defects is facilitated by and, in certain cases, only possible at all using 2-DDE.SummaryThe fetuses of 352 patients at between 16 and 38 weeks of gestation were studied by using two-dimensional Doppler echocardiography (2-DDE). In 32 fetuses, structural and/or functional abnormalities were detected. The advantages of 2-DDE are, in particular, rapid screening for flow abnormalities and, thus, shortening of the Doppler examination time. Further benefits include a rapid diagnosis of valvular regurgitation, valvular stenosis, and abnormal shunting of blood across the cardiac septa. The diagnosis of complex heart defects is facilitated by and, in certain cases, only possible at all using 2-DDE.ZusammenfassungZwischen der 17. und 39. Schwangerschaftswoche wurden 352 Patientinnen mittles der fetalen zweidimensionalen Doppler-Echokardiographie (2-DDE) untersucht. Bei 32 Feten wurden strukturelle und/oder funktionelle Anomalien nachgewiesen. Die Vorteile der 2-DDE waren: schnelles screening nach Flußanomalien und somit beträchtliche Verkürzung der Untersuchungszeit der Doppler-Echokardiographie; rasche Diagnose valvulärer Insuffizienzen und Stenosen sowie interventrikulärer Shunts. So ist die Diagnose komplexer kardialer Fehlbildungen erleichtert und in einzelnen Fällen erst durch die 2-DDE möglich.
Archives of Gynecology and Obstetrics | 1989
U. Gembruch; M. Hansmann; Dirk A. Redel; A. Gottschlich; Rainer Bald
Die Inzidenz angeborener Herzfehler ist 0,7%–0,8%. In 90% der Falle liegt ein multifaktorieller Erbgang zugrunde. Innerhalb dieser Gruppe liegt das Wiederholungsrisiko bei 2% – 5% (abhangig von Typ und Haufigkeit des Herzfehlers in der Bevolkerung), wenn ein Verwandter ersten Grades betroffen war (vorheriges Kind, Elternteil).
Ultrasound in Obstetrics & Gynecology | 1991
M. Hansmann; U. Gembruch; Rainer Bald; Matthias Manz; Dirk A. Redel