Background-The objectives of this study were to establish reference ranges for left and right cardiac output and to investigate blood flow distribution through the foramen ovale, ductus arteriosus, and pulmonary bed in human fetuses. Methods and Results-A prospective study was performed in 222 normal fetuses from 13 to 41 weeks of gestation with high-resolution color Doppler ultrasound. Cardiac output and ductal flow were calculated by use of vessel diameter and the time-velocity integral. Pulmonary blood flow was expressed as the difference between right cardiac output and ductal flow. Foramen ovale flow was estimated as the difference between pulmonary flow and left cardiac output. Gestational age-specific reference ranges are given for left, right, and biventricular output and volume of ductal blood flow, showing an exponential increase with gestational age. Median ratio of right to left cardiac output was 1.42 and was not associated with gestational age. Right cardiac output was 59% and left cardiac output was 41% of biventricular cardiac output. Median biventricular cardiac output was estimated to be 425 mL · min Ϫ1 · kg Ϫ1 fetal weight. Ductal blood flow was 46%, estimated pulmonary flow was 11%, and estimated foramen ovale flow was 33% of biventricular output. Conclusions-The study establishes reference ranges for fetal cardiac output and offers insights into the central blood flow distribution in human fetuses from 13 weeks to term. There is a clear right heart dominance. The estimated ratio of pulmonary blood flow to cardiac output is higher than in fetal lamb studies. (Circulation. 2001;103:1662-1668.)

Introduction: The German PID-NET registry was founded in 2009, serving as the first national registry of patients with primary immunodeficiencies (PID) in Germany. It is part of the European Society for Immunodeficiencies (ESID) registry. The primary purpose of the registry is to gather data on the epidemiology, diagnostic delay, diagnosis, and treatment of PIDs. Methods: Clinical and laboratory data was collected from 2,453 patients from 36 German PID centres in an online registry. Data was analysed with the software Stata® and Excel. Results: The minimum prevalence of PID in Germany is 2.72 per 100,000 inhabitants. Among patients aged 1–25, there was a clear predominance of males. The median age of living patients ranged between 7 and 40 years, depending on the respective PID. Predominantly antibody disorders were the most prevalent group with 57% of all 2,453 PID patients (including 728 CVID patients). A gene defect was identified in 36% of patients. Familial cases were observed in 21% of patients. The age of onset for presenting symptoms ranged from birth to late adulthood (range 0–88 years). Presenting symptoms comprised infections (74%) and immune dysregulation (22%). Ninety-three patients were diagnosed without prior clinical symptoms. Regarding the general and clinical diagnostic delay, no PID had undergone a slight decrease within the last decade. However, both, SCID and hyper IgE- syndrome showed a substantial improvement in shortening the time between onset of symptoms and genetic diagnosis. Regarding treatment, 49% of all patients received immunoglobulin G (IgG) substitution (70%—subcutaneous; 29%—intravenous; 1%—unknown). Three-hundred patients underwent at least one hematopoietic stem cell transplantation (HSCT). Five patients had gene therapy. Conclusion: The German PID-NET registry is a precious tool for physicians, researchers, the pharmaceutical industry, politicians, and ultimately the patients, for whom the outcomes will eventually lead to a more timely diagnosis and better treatment.

Based on a prospective study in more than 200 normal fetuses, the data provide gestational age specific reference ranges for blood flow velocity waveforms of the fetal pulmonary artery and the ductus arteriosus. The reference ranges may be helpful in prenatal diagnosis of cardiac malformations and ductal obstruction from 13 to 41 weeks of gestation.

Introduction !The umbilical cord (UC) is the essential life-sustaining connection between fetus and placenta. It constitutes a stable connection to the fetomaternal interface, while allowing fetal mobility that is essential for fetal development in general and neuromotor development in particular. This combination of mechanical stability and flexibility is due to the architecture of the UC. There is however a range of umbilical cord complications that may be life threatening to the fetus, and these too can be explained to a large extent by the cordʼs structural characteristics. Examination of cord vessels using Doppler ultrasound enables investigators to deduce the state of the fetoplacental vascular bed, providing essential information on the condition of the fetus. Development and Architecture of the Umbilical Cord !In its embryonic stage the UC develops in the region of the body stalk to become the embryoʼs connection to the fetal portion of the placenta (fetal placenta). The amniotic cavity expands from dorsal to ventral while the chorionic cavity shrinks in volume. During cephalo-caudal and lateral folding the early UC arises as it is "enveloped" by the expanding amnion (l " Fig. 1) (see also textbooks of embryology, www.embryology.ch). In this early stage at around 7-8 weeks postmenstrual age the UC contains the body stalk with umbilical vessels as well as other structures that will later regress and disappear entirely: the allantoic diverticulum (an outpouching from the endoderm connected to the (future) urinary bladder, later the urachus), as well as the extra-embryonic coelom that at this early stage still forms a connection to the cho- Abstract !The umbilical cord (UC) is a vital connection between fetus and placenta. It constitutes a stable connection to the fetomaternal interface, while allowing the fetal mobility that is of great importance for fetal development in general and fetal neuromotor development in particular. This combination of mechanical stability and flexibility is due to the architecture of the UC. There is however a range of umbilical cord complications that may be life threatening to the fetus and these too can be explained to a large extent by the cordʼs structural characteristics. This review article discusses clinically relevant aspects of UC ultrasound. Zusammenfassung !Die Nabelschnur ist die lebenswichtige Verbindung zwischen Fetus und Plazenta. Sie bildet einerseits eine stabile Verbindung zur zentralen Einheit des fetomaternalen Stoffwechsels und ermöglicht dem Feten andererseits eine Beweglichkeit, die für die körperliche -insbesondere die neuromotorische -Entwicklung von großer Bedeutung ist. Diese Kombination aus mechanischer Stabilität und Flexibilität begründet sich in der Architektur der Nabelschnur. Es gibt jedoch eine Reihe an Nabelschnurkomplikationen, die den Feten z. T. lebensbedrohlich gefährden können. Auch diese lassen sich vor allem auf die strukturellen Eigenschaften der Nabelschnur zurückfüh-ren. Im Rahmen einer Übersichtsarbeit werden klinisch relevante Asp...

The presented data derived from a study group of 222 normal fetuses provide in-vivo insights into the morphology of the ductus arteriosus and its relationship to the adjacent vessels. The reference ranges may be helpful in prenatal diagnosis of cardiac malformations and abnormalities of the ductus arteriosus, such as obstruction or aneurysm from 13 to 41 weeks of gestation.