Normal Cardiac Structures Research Articles

ISUOG Practice Guidelines (updated): fetal cardiac screening.

ISUOG Practice Guidelines (updated): fetal cardiac screening.

Acute Idiopathic Pulmonic and Tricuspid Regurgitation after Heart Transplant

Introduction Right sided valvular regurgitation is a rare complication after heart transplantation, and can occur with hyperacute rejection or later from repeated endomyocardial biopsy. Early surgical intervention has been recommended when managing a tricuspid regurgitant valve post transplantation. We describe a case of severe tricuspid and pulmonic valve regurgitation after heart transplantation. Case Report A 39 yo male with D-TGA, post Mustard repair that progressed into end stage HF. He underwent uncomplicated orthotopic heart transplantation with bicaval anastomosis from a young donor with normal cardiac structures and function on TEE and visual survey. Intraoperative TEE showed moderate tricuspid and moderate pulmonic valve regurgitation. A PA catheter was thought to be contributing to the central regurgitant jet; the RV size and function were normal, the PA pressures were also normal. Post operatively patient developed progressive right heart failure syndrome with worsening regurgitation despite diuresis and removal of the PA catheter. Endomyocardial biopsy did not show any signs of rejection. Repeated TEE showed normal biventricular function, torrential TR with pan systolic flow reversal in the hepatic vein due to non coaptation of the leaflets. The pulmonic valve was also severely insufficient with a central regurgitant jet and holodiastolic flow reversal in the pulmonary arteries. The patient underwent a tricuspid repair with a 30mm tricuspid ring and pulmonic valve replacement with a 25 mm bovine valve on POD 10. Surgical endomyocardial biopsy had no evidence of rejection. His heart failure symptoms resolved and he was discharged 4 weeks post op. Summary We describe a novel case of a 39 yo orthotopic heart transplant recipient with acute post operative concomitant TR and PI with right heart failure requiring a tricuspid ring annuloplasty and pulmonic valve replacement. To date, there are no such reported complications after heart transplant. The incidence of isolated tricuspid valve regurgitation after heart transplant have decreased with the bicaval transplantation technique however not eliminated. Literature suggests that isolated moderate to severe tricuspid valve regurgitation should under a repair or replacement early post transplantation. Pulmonic valve insufficiency is extremely rare after heart transplant and management strategies are not well defined.

Evaluation of the effect of deep inspiration breath-hold on radiation therapy for left breast cancer and the correlation between cardiac chest wall contact distance and cardiac exposure

Objective To compare the exposure to heart and other organs of the application of DIBH(deep inspiration breath-hold) and FB(free breath) in the left breast cancer radiotherapy, and the relationship between CCD (cardiac contact distance) and heart dose was analyzed. Methods Thirty patients with left breast cancer were examined with CT scans using DIBH and FB respectively, and then the dose was calculated by TPS(treatment planning system). The dose of heart, left anterior descending branch and left ventricle were analyzed by DVH(dose volume histogram). FB-CCDax (Axial cardiac chest wall contact distance) and FB-CCDps (sagittal heart chest wall contact distance) in CT images were measured based on FB. Results The parameters showed that, in radiotherapy with the application of DBIH technology, the irradiated volume of heart, left anterior descending branch(LAD), left ventricle(LV) of were significantly lower than that in the organs in the FB, the mean dose (Dmean) of heart of the former was 0.8 Gy, compared with 2.7 Gy in the latter one (P<0.005). The Dmean of LAD was 4.0Gy, compared with 12.7Gy in the latter one (P<0.001); The Dmean of LV was 1.2Gy, compared with 3.6Gy in the latter one (P<0.005). In the DIBH and FB radiotherapy, the Dmean of the heart, left anterior descending branch and left ventricle was correlated with FB-CCDps, but not with FB-CCDax. Conclusion DIBH is a simple treatment technique that can effectively reduce the cardiac radiation dose without loss of target dose.FB-CCDps is a potential predictor of cardiac exposure, and the longer the FB-CCDps distance is, the higher the cardiac dose is.The study found that at least 70% of patients with left breast cancer would benefit from DIBH and reduce the radiation exposure to normal cardiac structures, so DIBH should be used as a routine clinical application. Key words: Deep Inspiration Breath-hold; Breast Cancer; Cardiac dose; Radiotherapy; CCD

P22.06: HDliveFlow with spatiotemporal image correlation for diagnosing congenital heart diseases

To present our experiences of using HDliveFlow and/or HDliveFlow silhouette mode with spatiotemporal image correlation (STIC) to reconstruct normal and abnormal fetal cardiac structures, and to assess detection rates of these techniques for the three-vessel, and panoramic views in normal fetuses. 61 normal fetuses and three fetuses with congenital heart anomalies [transposition of great arteries (TGA), hypoplastic left heart syndrome (HLHS), and pulmonary valve stenosis (PS)] at 18-34 weeks were included. Detection rates of spatial three-vessel and panoramic views in normal fetuses were evaluated. In spatial three-vessel view, relationships and course of the outflow tracts and superior vena cava were clearly identified. The panoramic view facilitated visualisation of the course and relationships of out- and inflow tracts. Spatial relationships between cardiac chamber and vessels were clearly understood. Detection rate of spatial three-vessel view was 90.2%, for panoramic view was 75.4%. In TGA fetus, spatial parallel arrangement of aorta originating from the right ventricle and pulmonary artery left from left ventricle was clearly identified. In HLHS, extremely small aorta and tear-drop-like heart were depicted. In PS, a markedly large main pulmonary artery due to poststenotic dilatation was evident. HDliveFLow and HDliveFlow silhouette mode with STIC provide novel visual experience for operators due to clear visualisation of fetal cardiac structure. They may provide easier way of demonstration of spatial relationship among fetal cardiac chambers, great arteries, veins and the difference in the size of great vessels. These techniques might become important diagnostic modalities for assessment of fetal congenital heart disease.

Recognition of Normal Fetal Cardiac Structures

AbstractFetal heart examination requires in depth knowledge of fetal cardiac physiology and fetal cardiac anatomy. Therefore, the cardiac sonographer must possess considerable skills to acquire optimum images on cardiac anatomy on predefined standard views. An appropriate interpretation of acquired fetal cardiac images is also a basic requirement that is expected from a cardiac sonographer. Any cardiac ultrasound operator who performs the fetal heart scan is expected to recognize normal cardiac structures, to assess myocardial function and heart rhythm but also should be able to pick up any deviation from well-defined normality.

HDlive Silhouette Mode With Spatiotemporal Image Correlation for Assessment of the Fetal Heart.

The purpose of this article is to present our experience with normal and abnormal fetal cardiac structures reconstructed in the HDlive silhouette mode (GE Healthcare Japan, Tokyo, Japan) with spatiotemporal image correlation (STIC). Twenty-two fetuses with normal hearts and 1 fetus with a congenital heart anomaly (Ebstein anomaly) at 20 to 36 weeks' gestation were studied in the HDlive silhouette mode with STIC. In normal fetal hearts, 4 cardiac chambers and crisscross arrangements of the pulmonary artery and aorta were clearly identified. This modality facilitated visualization of the relationships and course of the outflow and inflow tracts, thus helping the operators more effectively understand the spatial relationships among the cardiac chambers and vessels. The opening and closing of mitral, tricuspid, pulmonary, and aortic valves were ascertained in the en face view of both atrioventricular valves and great vessels. In the fetus with Ebstein anomaly, a low attachment of the tricuspid valve and an enlarged right atrium were evident. The HDlive silhouette mode with STIC provides new visual experiences for physicians, owing to the anatomically clear depiction of fetal cardiac structures, and it may be an easier way to depict the spatial relationships among fetal cardiac chambers, great arteries, and veins.

Echocardiographic evaluation in Rett children with cardiac dysautonomia

The incidence of sudden death in Rett syndrome is greater than that of the general population. Previous studies suggested cardiac dysautonomia and long QT interval as a prime suspect cause but there are no echocardiographic studies in Rett girls. The aim of this study was the analysis of the cardiac dysautonomia and echocardiographic abnormalities in females affected with Rett syndrome as a possible explanation of the higher risk for sudden death, observed in these subjects. Standard transthoracic echocardiography, heart rate variability and corrected QT interval were studied in 32 Rett girls (4 ± 4.1 years) and in 30 age-matched healthy females (6.8 ± 2.1 years). All Rett girls had cardiac dysautonomia, with loss of physiological heart rate variability but normal cardiac structures, dimensions and function. These results suggest that sudden death in Rett girls may be linked to an electrical instability and not to cardiac structures or valve alterations. (J Pediatr Neurol 2004; 2(3): 145–148).

Four-Dimensional Color Doppler Reconstruction of the Fetal Heart With Glass-Body Rendering Mode

The investigators present their experience with normal fetal cardiac structures and congenital heart anomalies reconstructed using 4-dimensional color Doppler with glass-body rendering mode and spatiotemporal image correlation. Two normal fetuses and 6 fetuses with congenital heart anomalies (1 case each of ventricular septal defect, Ebstein's anomaly, hypoplastic left heart syndrome, and ductus arteriosus aneurysm and 2 of double-outlet right ventricle) at 26 to 36 weeks' gestation were studied using 4-dimensional color Doppler with glass-body rendering mode. In normal fetal hearts, blood flow through the 4 cardiac chambers and crisscross arrangements of the pulmonary artery and aorta were clearly recognized. In the fetus with a ventricular septal defect, significant shunt flow through the defect between the left and right ventricles was evident. In the fetus with Ebstein's anomaly, giant tricuspid regurgitant flow was noted. In the fetus with hypoplastic left heart syndrome, large tricuspid regurgitant flow was identified. In the fetuses with double-outlet right ventricles, large aortas and small pulmonary arteries leaving the right ventricles in parallel were clearly shown. In the fetus with a ductus arteriosus aneurysm, an enlarged ductus arteriosus following the pulmonary artery was clearly depicted. In conclusion, fetal 4-dimensional color Doppler may assist in the evaluation of spatial relations between the great vessels and both ventricles and differences in the sizes of the great vessels and cardiac chambers.

Chamber dimensions and functional assessment with coronary computed tomographic angiography as compared to echocardiography using American Society of Echocardiography guidelines.

Background:The correlation between normal cardiac chamber linear dimensions measured during retrospective coronary computed tomographic angiography as compared to transthoracic echocardiography using the American Society of Echocardiography guidelines is not well established.Methods:We performed a review from January 2005 to July 2011 to identify subjects with retrospective electrocardiogram-gated coronary computed tomographic angiography scans for chest pain and transthoracic echocardiography with normal cardiac structures performed within 90 days. Dimensions were manually calculated in both imaging modalities in accordance with the American Society of Echocardiography published guidelines. Left ventricular ejection fraction was calculated on echocardiography manually using the Simpson’s formula and by coronary computed tomographic angiography using the end-systolic and end-diastolic volumes.Results:We reviewed 532 studies, rejected 412 and had 120 cases for review with a median time between studies of 7 days (interquartile range (IQR25,75) = 0–22 days) with no correlation between the measurements made by coronary computed tomographic angiography and transthoracic echocardiography using Bland–Altman analysis. We generated coronary computed tomographic angiography cardiac dimension reference ranges for both genders for our population.Conclusion:Our findings represent a step towards generating cardiac chamber dimensions’ reference ranges for coronary computed tomographic angiography as compared to transthoracic echocardiography in patients with normal cardiac morphology and function using the American Society of Echocardiography guideline measurements that are commonly used by cardiologists.

Three-Dimensional HDlive Rendering Images of the Fetal Heart

Our objective is to describe our experience with reconstruction of normal fetal cardiac structures and congenital heart anomalies using the 3-D HDlive rendering mode with spatiotemporal image correlation (STIC). Four normal fetuses and three fetuses with congenital heart anomalies (Ebstein’s anomaly, hypoplastic left heart syndrome and tetralogy of Fallot) at 25–35 wk of gestation were studied using the 3-D HDlive rendering mode with STIC. In normal fetuses, the natural appearance of the dynamic motion of the foramen ovale flap and both atrioventricular valves was clearly visualized in real time in the four-chamber view. Moreover, new, realistic sensations of each leaflet of atrioventricular valves and semilunar valves of the pulmonary artery were obtained in the en face view of both atrioventricular valves and great vessels. In the case of Ebstein’s anomaly, the procedure rendered the natural and anatomically realistic appearance of significantly low attachment of the tricuspid valve and atrialized portion of the right ventricle. In hypoplastic left heart syndrome, thickened tricuspid and dysplastic pulmonary valves were clearly revealed. In tetralogy of Fallot, an overriding aorta and ventricular septal defect were realistically depicted. The 3-D HDlive rendering mode with STIC provides entirely new visual experiences for obstetricians and pediatric cardiologists owing to the anatomically realistic depiction of normal and abnormal fetal cardiac structures of the beating heart.

A morphometric study of the human fetal heart on post‐mortem 3‐tesla magnetic resonance imaging

To report on the feasibility of assessing cardiac structures on post-mortem 3-tesla MRI (pmMRI) and to provide morphometric data in fetuses without cardiac abnormalities. Retrospective single center study on 3T pmMRI of 39 consecutive fetuses without cardiac abnormalities (13-38 weeks of gestation). Fetal cardiac anatomy was assessed and measurements of cardiac structures were performed on T2-weighted 3D multiplanar reconstructed images. Linear regression analysis was performed to examine changes of cardiac dimensions during gestation. The four-chamber view of the fetal heart could be obtained and the measurements of cardiac chambers and ventricular walls could be performed in all 39 cases. The aorta and the pulmonary artery were visualized and their diameters were measured in 38 (97.4%) fetuses, ductus arteriosus in 32 (82%). All measurements showed strong linear correlation with gestational age. The relationship of the diameters of the pulmonary artery, aorta, and ductus arteriosus remained constant over pregnancy. All these observations are consistent with what is known from prenatal ultrasound. The present study proves the feasibility of visualizing normal cardiac structures on 3-tesla pmMRI in fetuses beyond 14 weeks. We provide morphometric data that may enable diagnostic evaluation of cardiac abnormalities on pmMRI.

Lack of clean water exacerbates cholera outbreak in Haiti

<h3>Abstract</h3> <h3>Background</h3> Congenital heart disease (CHD) affecting the conotruncal region of the heart, occur in half of patients with 22q11.2 deletion syndrome. This syndrome is a rare disorder with relative genetic homogeneity that can facilitate identification of genetic modifiers. Haploinsufficiency of <i>TBX1</i>, mapped to the 22q11.2 region, encoding a T-box transcription factor, is one of the main genes for the etiology of the syndrome. We suggest that genetic modifiers of CHD in patients with 22q11.2 deletion syndrome may be in the <i>TBX1</i> gene network. <h3>Methods</h3> To identify genetic modifiers of 22q11.2 deletion syndrome, we analyzed whole genome sequence of subjects with 22q11.2DS, of which 456 were cases with conotruncal heart defects and 537 were controls with normal cardiac structures. We retained the most damaging rare coding variants and examined 19 functional gene sets for association that were weighted upon expression of genes in cardiac progenitor cells in mouse embryos identified by RNA-sequencing. <h3>Results</h3> We identified rare damaging coding variants in chromatin regulatory genes as modifiers of conotruncal heart defects in 22q11.2DS. Chromatin genes with recurrent damaging variants include <i>EP400, KAT6A, KMT2C, KMT2D, NSD1, CHD7</i> and <i>PHF21A</i>. In total, we identified 37 chromatin regulatory genes, that may increase risk for conotruncal heart defects in 8.5% of 22q11.2 deletion syndrome cases. Many of these genes were identified as risk factors for sporadic CHD in the general population increasing the likelihood that these genes are medically important contributors for CHD. These genes are co-expressed in cardiac progenitor cells with <i>TBX1</i>, suggesting that they may be in the same genetic network. Some of the genes identified, such as <i>KAT6A, KMT2C, CHD7</i> and <i>EZH2</i>, have been previously shown to genetically interact with <i>TBX1</i> in mouse models, providing mechanistic validation of these genes found. <h3>Conclusions</h3> Our findings indicate that disturbance of chromatin regulatory genes impact a <i>TBX1</i> gene network serving as genetic modifiers of 22q11.2 deletion syndrome. Since some of these chromatin regulatory genes were found in individuals with sporadic CHD, we suggest that there are shared mechanisms involving the <i>TBX1</i> gene network in the etiology of CHD.

Frequent Premature Ventricular Contractions in an Orbital Spaceflight Participant

Commercial spaceflight participants on orbital flights typically are older than career astronauts and they often have medical conditions that have not been studied at high g or in microgravity. This is a case report of a 56-yr-old orbital spaceflight participant with essential tremor and frequent premature ventricular contractions that occurred at rates up to 7000 per day. Before training and spaceflight, he was required to complete extensive clinical investigations to demonstrate normal cardiac structures and the absence of cardiac pathology. The evaluation included signal averaged ECG, transthoracic stress echocardiography, exercise tolerance tests, electrophysiological studies, cardiac MRI, electron beam CT, Holter monitoring, and overnight oximetry. While no cardiac pathology was demonstrated, the Russian medical team required that the PVCs be treated prior to training and spaceflight. For the initial flight, a selective beta-1 receptor beta blocker was used and for the second a calcium channel blocker was used in combination with a nonselective beta blocker for tremor control. Analogue environment testing assured that this combination of medications was compatible. The spaceflight participant's PVCs were incompletely suppressed with a low-dose selective beta-1 blocker, but were well suppressed by a calcium channel blocker. He tolerated in-flight periodic use of a nonselective beta blocker in combination with a calcium channel blocker. In-flight ECG and blood pressure monitoring results were normal, and an ECG obtained midmission and on landing day showed successful PVC suppression. He did not have any cardiac difficulty with launch, on-orbit operations, entry, or recovery

Three-Dimensional Transesophageal Echocardiography Is a Major Advance for Intraoperative Clinical Management of Patients Undergoing Cardiac Surgery

Echocardiography is a key assessment tool for the evaluation of cardiac structure and function. The ability to image cardiac structures using 3-dimensional (3D) echocardiography is evolving. In this article, we present some of the key features of the emerging 3D technology and review its applications with an emphasis on real-time 3D transesophageal echocardiography.

Distended azygos and hemiazygos vein without interrupted inferior vena cava in a case of agenesis of the ductus venosus

A 26-year-old woman, gravida 2 para 0, was referred for a detailed scan including uterine artery Doppler ultrasound examination, as her previous pregnancy ended in the intrauterine death of twins. Uteroplacental resistance in the index pregnancy was markedly increased with bilateral notching of the uterine artery waveform. At 26 weeks detailed fetal echocardiography showed normal cardiac structures. However, a blood vessel with venous flow velocity waveforms running in parallel to the thoracic aorta, which was classified as a distended azygos vein, was detected by color Doppler ultrasound imaging (Figure 1). The possibility of a heterotaxy syndrome could be excluded due to situs solitus and a non-interrupted inferior vena cava (IVC) (Figures 2-4). Furthermore, abnormal draining of the umbilical vein (UV) directly into the abdominal part of the IVC was detected (Figures 3 and 4). This was classified as agenesis of the ductus venosus (DV) with portocaval shunt, and was similar to that described in a recently published case1, 2. Posterior to this connection a collateral venous vessel originated from the IVC, joining the dilated hemiazygos vein on the left side of the abdominal aorta. In the thorax the hemiazygos vein crossed to the right, joining the azygos vein (Figure 5), before finally running into the superior vena cava. Color Doppler ultrasound examination showing distended azygos vein (red) posterior to the thoracic aorta (blue). Ultrasound scan showing normal four-chamber view and cross-section through the thoracic aorta and azygos vein. Gray-scale ultrasound image showing direct connection of the umbilical vein to the inferior vena cava. Color Doppler image with glass-body rendering, showing connection of the umbilical vein (UV) and the inferior vena cava (IVC). Color Doppler image of the fetal thoracic region, showing the hemiazygos vein crossing from the left to the right side and joining the azygos vein. A possible complication caused by a direct connection between the UV and the IVC may be the development of high-output cardiac failure owing to chronic volume overload of the central venous system and the heart3, 4. However, in our case no signs of cardiac overload were detected. At 31 + 4 weeks the woman developed pre-eclampsia and fetal arterial blood flow redistribution indicated low resistance in the middle cerebral artery. After induction of lung maturity, a boy with a birth weight of 1550 g, Apgar scores of 7, 9 and 9 at 1, 5 and 10 min, respectively, and arterial pH 7.28 was delivered by Cesarean section. The neonatal course was uneventful. Pediatric echocardiography at the age of 10 weeks showed normal cardiac function, a closed DV and an enlarged hemiazygos vein on the left side of the abdominal aorta. The liver circulation was normal. At the time of writing, the infant was 10 months old and healthy. To our knowledge, this is the first description of a distended azygos/hemiazygos vein coexistent with a non-interrupted IVC and without association with heterotaxy syndrome. The collateral venous circulation through the hemiazygos vein in the presence of an abnormal direct connection between the UV and IVC may have resulted in a protective effect against cardiac overload. However, owing to the development of pre-eclampsia and fetal blood flow redistribution with decreasing resistance in the middle cerebral artery, a Cesarean section was indicated. We would advise longitudinal fetal monitoring with Doppler ultrasound imaging and echocardiography in similar cases. H. Hille*, R. Chaoui , S. Renz , K. Hecher?, * Lappenbergsallee 50, Hamburg, D-20257, Germany, Center for Pediatric Cardiology, Hamburg, Germany, Obstetrics and Fetal Medicine, University Medical Center, Hamburg, Germany, ? Center for Prenatal Diagnosis and Human Genetics, Berlin, Germany

Increasing the Detection Rate of Normal Fetal Cardiac Structures: A Real-Time Approach

The purpose of this study was to determine if acquiring real-time sweeps of the fetal heart would be a more effective method of identifying normal cardiac structures compared with using static images during routine second-trimester obstetric sonograms. Subjects were scanned using three different techniques. The static image acquisition (protocol A) included three images of the fetal heart. Protocol B used two gray-scale sweeps through the fetal heart. Protocol C acquired three color loops of the fetal heart. The sweeps demonstrated a complete normal cardiac assessment in 71% of studies, compared with the static image and color Doppler techniques that completed a normal cardiac assessment in only 39% of studies, respectively. The real-time technique detected four chambers, the left ventricular outflow tract (LVOT), the right ventricular outflow tract (RVOT), the LVOT/RVOT crossover, and size and axis of the heart with a greater frequency than the static images and color loops in all cases. In addition, the real-time technique was able to demonstrate the pulmonary veins in 56% of cases compared with 3.6% for static images. The color Doppler acquisition demonstrated blood flow through the atrial-ventricular and semilunar valves in 86% of cases.

Münchhausen Syndrome Simulating Acute Aortic Dissection

A young adult man presented to the emergency department reporting a convincing story for acute aortic dissection, a disorder in which diagnostic evaluations should occur in parallel with pharmacologic management. Transesophageal echocardiography demonstrated normal cardiac and aortic structures. Additional history was notable for extensive travel across numerous medical facilities with associated misrepresentation of his diagnosis and treatment. The patient was willing to undergo unpleasant and invasive procedures and succeeded at least once in the past to deceive clinicians to the point of performing a median sternotomy. The intentional presentation of false information leading to unnecessary treatments is consistent with Münchhausen Syndrome.

Live Three‐Dimensional Right Parasternal and Supraclavicular Transthoracic Echocardiographic Examination*

In the present study, we describe the usefulness of the recently developed technique of live three-dimensional transthoracic echocardiography in the assessment of normal cardiac structures and adjacent vessels using the right parasternal and supraclavicular approaches. Examples of some abnormalities diagnosed from these approaches are also illustrated.

Real-time three-dimensional fetal echocardiography using matrix probe

To investigate the feasibility of using real-time three-dimensional echocardiography (3DE) to evaluate the fetal heart. Sixty fetuses were studied with gestational age between 22 and 34 weeks. The fetal heart was normal in 44 fetuses. In 16 fetuses, the fetal heart had morphologic abnormalities (hypoplastic left ventricle in 4, tetralogy of Fallot in 2, Ebstein anomaly in 2, rhabdomyomes in 2, hypoplastic right ventricle in 1) or myocardial dysfunction (in 5 fetuses). Real-time 3DE was performed with a cardiac matrix probe (2-4 MHz). Two modalities of 3D imaging were performed: Biplane and Live 3D imaging. Real-time 3DE was performed successfully in 93%. Biplane imaging allowed a multiplanar scanning of the fetal heart. Using rotation, lateral and vertical tilts, the normal cardiac structures were identified from a unique reference image plane: atria and ventricles, atrioventricular valves, aorta and pulmonary artery. Live 3D imaging allowed surface imaging of the fetal heart. 'En face' view of the foramen ovale from the right atrium was obtained, showing the shape of the orifice. By cropping the pyramidal imaging volume, ascending aorta, aortic arch and ductus arteriosus were depicted from a single dataset. In pathologic fetal hearts, 3DE was helpful for (1) localizing multiple cardiac tumors; (2) estimating size and function of the right and left ventricles; (3) evaluating mechanism of valvular regurgitation and pulmonary obstruction. Real-time 3DE is a feasible and non-time-consuming method, allowing a multiplanar scanning and new inside 3D views of the fetal heart.

Manipulating parallel circuits: the perioperative management of patients with complex congenital cardiac disease

In all patients undergoing cardiac surgery, the effective delivery of oxygen to the tissues is of paramount importance. In the patient with relatively normal cardiac structures, the pulmonary and systemic circulations are relatively independent of each other. In the patient with a functional single ventricle, the pulmonary and systemic circulations are dependent on the same pump. As a consequence of this interdependency, the haemodynamic changes following complex palliative procedures, such as the Norwood operation, can be difficult to understand. Comparison of the newly created surgical connections to a simple set of direct current electrical circuits may help the practitioner to successfully care for the patient. In patients undergoing complex palliations, the pulmonary and systemic circulations can be compared to two circuits in parallel. Manipulations of variables, such as resistance or flow, in one circuit, can profoundly affect the performance of the other circuit. A large pulmonary flow might result in a large increase in the saturation of haemoglobin with oxygen returning to the heart via the pulmonary veins at the expense of a decreased systemic flow. Accurate balancing of these parallel circulations requires an appreciation of all interventions that can affect individual components of both circulations.