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D A Redel

Publications and source records attributed to D A Redel.

33 records · Page 2Linked to original sources
PubMed1989

Fetal complete heart block: antenatal diagnosis, significance and management.

Complete heart block was diagnosed prenatally in 21 fetuses. Associated structural cardiac defects were present in 18 fetuses, in particular complete atrioventricular canal with atrial isomerism (5 cases), and 'corrected' transposition of the great arteries (4 cases). Maternal systemic lupus erythematosus was proved in only one case. In 11 fetuses, intra-uterine congestive heart failure with the signs of non-immune hydrops fetalis occurred. In all 11 fetuses, the hydrops was associated with a cardiac defect, in particular complete atrioventricular canal with atrial isomerism in 5 cases. A review of the literature confirms that only the association of complete heart block and cardiac malformation can cause intra-uterine congestive heart failure, whereas in the case of fetal complete heart block without cardiac malformation or with prenatally hemodynamically insignificant cardiac malformation, congestive heart failure is rare. Only 30% of newborns with complete heart block have associated cardiac malformations. In our series, however, 86% of the fetuses with complete heart block had cardiac malformations. The most important reason for this percentage discrepancy is that almost all fetuses with associated severe cardiac defects, in particular atrioventricular canal defects, develop heart failure which frequently results in prenatal death. Thus, fetal deaths are not included in pediatric statistics. Nevertheless, fetuses with isolated complete heart block generally do not develop heart failure and in almost all of the cases are born alive.

Adult↗
PubMed1989

[Color Doppler echocardiography--possibilities and limits of a new procedure].

Color-flow-mapping (CFM) has added a new dimension to the echocardiographic diagnosis of heart disease. Typical characteristics of blood flow, i.e., flow direction, relative velocities, and degree of "turbulence" in the cardiovascular system are displayed within the two-dimensional echocardiographic image. This gives hitherto unknown insights into the physiology of blood flow velocity profiles. Pathological flow patterns in heart disease are easily recognizable and their display within the CFM image allows a straightforward diagnosis of the underlying heart disease. This feature is especially valuable in the diagnosis of heart disease with shunt and in valvular regurgitations in children, as well as in adults. CFM is also useful for optimal angulation in the assessment of gradients using the simplified Bernouilli equation. It is characterized by a remarkably high diagnostic sensitivity and specificity. However, quantitation of heart disease causing volume load is still limited by the lack of standardization in the process of color encoding of the Doppler data. Digital flow mapping (DFM) offers an opportunity for the standardized sampling of Doppler data offering development of an established modality for color encoding. Moreover, DFM offers the opportunity for calculation of angle-corrected velocities. Here a new non-invasive way for a reliable calculation of cardiac output may present itself.

Blood Flow Velocity↗
PubMed1989

[Detection and localization of the ventricular septum defect using color Doppler echocardiography. Sensitivity, specificity, limitations].

In part 1 of this study 50 healthy children and 56 patients with known VSD were examined by color-Doppler-echocardiography to derive criteria for the diagnosis of a VSD by this technique. Using a defined Nyquist velocity the healthy children showed a monochrome ventricular bloodflow pattern. In patients with VSD and an interventricular pressure gradient greater than 15 mm Hg a turquois-yellow jet could be seen additionally in the ventricle with the lower pressure. The same pattern could be observed within the defect itself, except for four patients, in whom the VSD could not be visualized by two-dimensional echocardiography. In these patients, however, the VSD could be localized by tracing the jet to the septal endocardium. In patients with equal left and right ventricular pressures a monochrome transseptal bloodflow could be seen. Its color pattern was not significantly different from the normal bloodflow pattern. In these cases it was difficult to diagnose a small VSD, if the defect itself could not be visualized. Thus, the following criteria for the diagnosis of a VSD by color-Doppler-echocardiography were derived depending on the interventricular pressure gradient: 1) Interventricular pressure gradient greater than 15 mm Hg: visualization of the VSD-jet including its origin at the septal endocardium. 2) Equal left and right ventricular pressures: visualization of the VSD as echo drop-out as well as a transseptal bloodflow. Using these criteria, sensitivity and specificity of color-Doppler-echocardiography in the detection of VSD were evaluated in part II; 234 consecutive patients, of which 119 had a VSD, were examined. All had undergone cardiac catheterisation. A high sensitivity of 98.3% and a specificity of 99.1% were found. Diagnostic problems remain in patients with a small VSD and also in patients with equal left and right ventricular pressures. In particular, multiple VSD with equal left and right ventricular pressures are difficult to visualize completely, as compared to cases with significant interventricular pressure gradients.

Adolescent↗
PubMed1988

[Cardiologic diagnosis using color Doppler echocardiography].

Colour-coded Doppler echocardiography (Colour Flow Imaging) is a new noninvasive method that offers new perspectives in the cardiographical diagnosis of cardiac defects with regard to diagnostic safety, easily interpreted manner of presentation, and in coping with the complexities of cardiac blood flow. This method also helps to optimise the use of well-established methods such as continuous-wave Doppler echocardiography enabling quantitative pressure measurement in children. Finally, the quantifiability of regurgitations and shunt lesions will be considerably improved by the introduction of digital flow mapping which is expected to be introduced in near future.

Adult↗
PubMed1988

[Non-immunologically-induced hydrops fetalis in complete atrioventricular block of the fetus. A summary of 11 prenatally diagnosed cases].

In 11 of 21 fetuses with prenatally diagnosed complete heart block, congestive heart failure with signs of non-immune hydrops fetalis was seen. In all 11 fetuses, cardiac malformations were present: complete atrioventricular canal with levocardia, situs inversus viscerum, and polysplenia: 5 cases; tricuspid atresia with situs inversus viscerum, endocardial fibroelastosis, common atrium with aortic valve atresia, hypoplastic left heart, atrial septal defect of secundum type: one case each. All these cardiac malformations can also cause intrauterine heart failure without heart block except hypoplastic left heart and atrial septal defect. A review of the literature confirms, that only the association between complete heart block and cardiac malformation--in particular AV-canal and endocardial fibroelastosis--can cause an intrauterine congestive heart failure, whereas in the case of fetal complete heart block without cardiac malformation or with prenatally hemodynamically insignificant cardiac malformations--in particular "corrected" transposition of great arteries--a congestive heart failure is rare.

Echocardiography↗
PubMed1988

[2-dimensional color-coded fetal Doppler echocardiography--its value in prenatal diagnosis].

105 fetuses between 16 and 38 weeks of gestation were studied by fetal echocardiography using color-coded two-dimensional Doppler-echocardiography (2-DDE). Two-dimensional, M-mode, and spectral-Doppler analyses were also performed. In 11 fetuses, structural and/or functional abnormalities were detected. Abnormalities were correctly excluded in all other fetuses. The advantages of the 2-DDE are, in particular: rapid screening for flow abnormalities in the fetal heart and, thus, shortening of the Doppler-examination time; furthermore, a rapid diagnosis of valvular regurgitation, valvular stenosis and abnormal shunting of blood across the interatrial and interventricular septa; the diagnosis of complex congenital heart defects is facilitated by and, in certain case, only possible using 2-DDE.

Blood Flow Velocity↗
PubMed1988

Intrauterine therapy of fetal tachyarrhythmias: intraperitoneal administration of antiarrhythmic drugs to the fetus in fetal tachyarrhythmias with severe hydrops fetalis.

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.

Adult↗
PubMed1986

[Diagnosis of congenital heart defects using color-coded Doppler echocardiography].

Color Doppler echocardiography (CDE) enables visualization of blood flow and of cardiac morphology within color coded two-dimensional images. The diagnostic usefulness of this method in pediatric cardiology has been analyzed based on studies performed in 2414 children. Normal cardiac findings were seen in 769 patients according to the clinical and echocardiographic examinations. Normal diastolic inflow into the ventricles in the apical four-chamber-view is characterized by a similar distribution of the color spectrum across the inflow tracts, blood flowing on the two sides of the heart is completely separated from each other. Normal systolic outflow imaged from parasternal position shows an increase in velocity in the outflow tract passing through the semilunar valves without any change in flow patterns. Heart disease was present in 1645 patients, simple cardiac defects were found in 1473 cases and complex heart disease in 172 cases. Shunt lesions are detectable by the demonstration of blood flow in regions where normally no flow is detectable, flow velocities being pathologically increased in many cases. Diagnostic sensitivity and specificity of CDE as compared to invasive procedures is between 96 and 98%. In left-to-right shunting the shunt flow can be followed into the right-sided cardiovascular regions where its extent is a measure for the size of the shunt as indicated by initial results. In ventricular septal defects, bidirectional shunting is indicative of a rise in pressure in the right ventricle and can be reliably detected with the use of CDE. In valvular stenoses high flow velocities are found in the appropriate time which are associated with turbulence and poststenotic eddies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

MR angiography of congenital heart disease: value of segmented two-dimensional inflow technique and maximum-intensity-projection display.

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40-50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65 degrees and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.

Aorta↗
PubMedDate not supplied

Occlusion of the neonatal patent ductus arteriosus with a simple retrievable device: a feasibility study.

PURPOSE: To examine the feasibility of transvenous placement of a new memory-shaped, small, retrievable coil that has a smaller-caliber delivery system than currently available devices, for closure of the patent ductus arteriosus (PDA). METHODS: Through 4 or 5 Fr vascular sheaths and 4 or 5 Fr end-hold catheters, the coils were delivered and placed in piglets (n = 10) with PDA. The coils were made from 0.018" (0.46 mm) or 0.028" (0.71 mm) stainless steel guidewire. Mounted for delivery, the new device has the appearance of a conventional guidewire. This neonatal PDA model was created without major surgery or drugs by stenting the ductus arteriosus. RESULTS: The memory-shaped coils were easily delivered. Coils not optimally placed were retrieved and repositioned. Occlusion of the ductus arteriosus as early as a half-hour after delivery was shown angiographically and confirmed by histopathology. CONCLUSION: This new, small-caliber, simple device was found to be effective for closure of the PDA in this animal model. Longer-term observations are needed.

Animals↗
PubMedDate not supplied

Acute mitral regurgitation due to chordal rupture in a patient with neonatal Marfan syndrome caused by a deletion in exon 29 of the FBN1 gene.

The neonatal Marfan syndrome is an autosomal dominantly inherited disease with an extremely poor prognosis. This report gives a clinical and echocardiographic description of an infant with a mutation in exon 29 of the fibrillin-1 gene (FBN1), a region in which this severe form of Marfan syndrome seems to cluster. The infant died at the age of 3 months due to severe acute mitral regurgitation leading to intractable heart failure.

Acute Disease↗
PubMedDate not supplied

Flow analysis in the pulmonary trunc in fetuses with tetralogy of Fallot by colour Doppler flow mapping; two case reports.

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.

Adult↗
PubMedDate not supplied

Diagnosis and follow-up of congenital heart disease in children with the use of two-dimensional Doppler echocardiography.

Two-dimensional echocardiography (2D) represents a major advance in non-invasive diagnosis of congenital heart disease (CHD) in children. Nevertheless it has diagnostic limitations in nearly all kinds of heart lesions. These can be overcome for the most part by integration of a pulsed Doppler system. This may be called two-dimensional Doppler echocardiography (2DD). Hereby blood flow information is added to the 2D image. Some common types of CHD including ventricular and atrial septal defects, persistent ductus arteriosus, pulmonic stenosis and coarctation are described with their typical 2DD findings. Non-invasive follow up of children with CHD and early recognition of typical complications can be achieved reliably using 2DD. Future prospects consist in a more quantitative diagnostic application of 2DD.

Adolescent↗
PubMedDate not supplied

[Wolff-Parkinson-White syndrome with paroxysmal supraventricular tachycardias of the fetus and the newborn--case report].

Paroxysmal supraventricular tachycardia causing an intrauterine congestive heart failure was diagnosed in a fetus at 33 week's gestation. After maternal digitalization the tachycardias and the signs of heart failure disappears. Postpartum a Wolff-Parkinson-White syndrome was recognised by electrocardiography. The paroxysmal supraventricular tachycardias of the newborn was terminated abruptly by intravenous application of propafenon. Recurrences were prevented by the oral administration of propafenon.

Adult↗