Project description:Scimitar syndrome is a variant of partial anomalous pulmonary venous connection (PAPVC), in which all or part of the right lung is drained by right pulmonary veins that anomalously connect to the inferior vena cava (IVC). The affected lung and its associated airways are often hypoplastic. In addition, aortopulmonary collateral vessels may be involved on the affected side, causing sequestration of that side; such involvement is commonly associated with cardiac defects. We report a case of infantile scimitar syndrome that involved a typical association with the right lung, but with extremely unusual associations with congenital hydrocephalus and heart blockage. The presentation of this case and the role of different diagnostic approaches and management are discussed.
Project description:A 56-year-old Chinese man presented with giddiness and vertigo. Subsequent chest radiography showed the classic scimitar sign of an abnormal pulmonary venous return. Further evaluation with non-contrast computed tomography substantiated the finding of a partial anomalous venous drainage pattern and identified an associated rare lung anomaly, horseshoe lung. The imaging findings of scimitar syndrome and its association with horseshoe lung are reviewed.
Project description:BackgroundScimitar syndrome (SS) comprises of an anomalously draining right pulmonary vein (APV), to the inferior vena cava (IVC), maldevelopment of the right pulmonary artery (RPA), and the right lung, with variable number of aorto-pulmonary collaterals (APC) to the right lung. It can cause pulmonary hypertension if left untreated. Surgical correction is the method of choice. We report a case of variant SS with dual drainage of the APV to the IVC and left atrium (LA) that was addressed with a transcatheter approach.Case summaryA 13-year-old child was evaluated for dyspnoea. Chest x-ray and transthoracic echo (TTE) were suggestive of SS with an additional central atrial septal defect (ASD). Cardiac computed tomography (CT) revealed dual drainage of the APV to the IVC and via a meandering vein to the LA and three APCs. The ASD was closed, and the APCs were coiled. The connection of the APV to the IVC was closed with a device, rerouting the pulmonary vein blood to the LA. The child is doing well on follow-up after 2 years.DiscussionVariant forms of SS are rare. Our case had ASD, multiple APCs, well-developed RPA and right lung and a dual drainage of the APV. This allowed for transcatheter management. Otherwise, surgery is the default choice. Multimodality imaging with TTE, CT, magnetic resonance imaging, and cardiac catheterization will help in diagnosis and anatomical delineation.
Project description:Scimitar syndrome is a rare congenital anomaly where the right pulmonary veins return to the inferior vena cava (IVC) just below the diaphragm. On chest X-ray (CXR), an IVC catheter will be in a bizarre location outside the heart if it inadvertently passes into the scimitar vein rather than into the right atrium.
Project description:BackgroundScimitar syndrome is a rare congenital disease characterized by partial or total anomalous pulmonary venous return from the right lung into the systemic venous system, and accounts for 0.5-2% of all congenital heart disease. Severe forms of the disease are diagnosed in childhood. However, because of the benign form of the syndrome in adults, many are asymptomatic, or present only mild symptoms including exertional dyspnoea, arrhythmias, and respiratory infections. We report an atypical presentation with hepatomegaly.Case summaryA 24-year-old woman was evaluated for abdominal discomfort. Physical examination revealed a remarkable hepatomegaly. Chest X-ray revealed dextroversion, enlargement of the right cavities, and a curvilinear opacity known as 'scimitar sign'. A transthoracic echocardiography demonstrated right ventricular dilation and a venous collector draining into right suprahepatic vein, which was severely dilated, with large hepatomegaly. Scimitar syndrome was confirmed by magnetic resonance imaging (MRI). Therefore, the patient underwent surgery, redirecting the pulmonary venous return to left atrium. Three months later, the patient remained asymptomatic and both the hepatomegaly and the right chamber volumes normalized.DiscussionAbdominal discomfort, as in our clinical case, is a highly atypical presentation of scimitar syndrome. It is important for physicians to be aware that diagnostic suspicion can be established from a chest X-ray, on which the scimitar sign can be distinguished in many cases. The diagnosis must be confirmed with other imaging modalities, such as echocardiography, MRI, or computed tomography. Corrective surgery may relieve the symptoms related to liver congestion at follow-up.
Project description:Heart rate biologging has been successfully used to study wildlife responses to natural and human-caused stressors (e.g., hunting, landscape of fear). Although rarely deployed to inform conservation, heart rate biologging may be particularly valuable for assessing success in wildlife reintroductions. We conducted a case study for testing and validating the use of subcutaneous heart rate monitors in eight captive scimitar-horned oryx (Oryx dammah), a once-extinct species that is currently being restored to the wild. We evaluated biologger safety and accuracy while collecting long-term baseline data and assessing factors explaining variation in heart rate. None of the biologgers were rejected after implantation, with successful data capture for 16-21 months. Heart rate detection accuracy was high (83%-99%) for six of the individuals with left lateral placement of the biologgers. We excluded data from two individuals with a right lateral placement because accuracies were below 60%. Average heart rate for the six scimitar-horned oryx was 60.3 ± 12.7 bpm, and varied by about 12 bpm between individuals, with a minimum of 31 bpm and a maximum of 188 bpm across individuals. Scimitar-horned oryx displayed distinct circadian rhythms in heart rate and activity. Heart rate and activity were low early in the morning and peaked near dusk. Circadian rhythm in heart rate and activity were relatively unchanged across season, but hourly averages for heart rate and activity were higher in spring and summer, respectively. Variation in hourly heart rate averages was best explained by a combination of activity, hour, astronomical season, ambient temperature, and an interaction term for hour and season. Increases in activity appeared to result in the largest changes in heart rate. We concluded that biologgers are safe and accurate and can be deployed in free-ranging and reintroduced scimitar-horned oryx. In addition to current monitoring practices of reintroduced scimitar-horned oryx, the resulting biologging data could significantly aid in 1) evaluating care and management action prior to release, 2) characterizing different animal personalities and how these might affect reintroduction outcomes for individual animals, and 3) identifying stressors after release to determine their timing, duration, and impact on released animals. Heart rate monitoring in released scimitar-horned oryx may also aid in advancing our knowledge about how desert ungulates adapt to extreme environmental variation in their habitats (e.g., heat, drought).
Project description:BackgroundScimitar syndrome is a rare CHD composed of partial anomalous pulmonary venous connection from the right lung, via a scimitar vein, to the inferior vena cava rather than the left atrium. Genetic conditions associated with scimitar syndrome have not been well investigated at present.MethodsOur study included patients with scimitar syndrome diagnosed at Texas Children's Hospital from January 1987 to July 2020. Medical records were evaluated to determine if genetic testing was performed, including chromosomal microarray analysis or whole-exome sequencing. Copy number variants identified as pathogenic/likely pathogenic and variants of unknown significance were collected. Analyses of cardiac and extracardiac findings were performed via chart review.ResultsNinety-eight patients were identified with scimitar syndrome, 89 of which met inclusion criteria. A chromosome analysis or chromosomal microarray analysis was performed in 18 patients (20%). Whole-exome sequencing was performed in six patients following negative chromosomal microarray analysis testing. A molecular genetic diagnosis was made in 7 of 18 cases (39% of those tested). Ninety-six per cent of the cohort had some type of extracardiac finding, with 43% having asthma and 20% having a gastrointestinal pathology. Of the seven patients with positive genetic testing, all had extracardiac anomalies with all but one having gastrointestinal findings and 30% having congenital diaphragmatic hernia.ConclusionsGenetic testing revealed an underlying diagnosis in roughly 40% of those tested. Given the relatively high prevalence of pathogenic variants, we recommend chromosomal microarray analysis and whole-exome sequencing for patients with scimitar syndrome and extracardiac defects.
Project description:ObjectiveA review of our center's experience before March 2011 showed that one half of 36 patients who had a baffling or reimplantation procedure to repair scimitar syndrome developed pulmonary vein obstruction. We analyzed the results of a new operation that enlarges the left atrium and avoids circuitous pathways or tension on the scimitar pulmonary vein.MethodsBetween April 2011 and November 2018, 22 patients underwent scimitar vein surgery; 11 had baffling or reimplantation and 11 only had the new operation that included resection of the atrial septum with removal of the muscular limbus. The left atrium was pulled down toward the scimitar vein and a V-shaped incision made at the scimitar vein atrial junction with the space filled with a pulmonary homograft. If the scimitar vein coursed adjacent to the atrium, a V-shaped incision was made into the scimitar vein and directly anastomosed to the atrium. A patch of autologous pericardium was used to septate the atrium and an additional patch placed anteriorly to augment the inferior vena cava.ResultsOf the 11 patients who had baffling or reimplantation, 5 developed pulmonary vein obstruction between 45 days and 9.5 months after surgery associated with baffle thrombosis or tension on the pulmonary vein. None of the 11 patients who only had the new procedure developed pulmonary vein obstruction during postoperative monitoring up to 3.6 years.ConclusionsPatients having only the multipatch procedure for repair of scimitar syndrome have not developed postoperative pulmonary vein obstruction in the short to intermediate term.