Clinical presentation of Scimitar syndrome varies greatly from one individual to another. However, an asymptomatic course is usually observed in adult patients, in whom this syndrome may be incidentally diagnosed. On the other hand, a symptomatic and often more severe course is observed in infants, with symptoms of heart failure, tachypnea, tachycardia, and sometimes hemoptysis [10].

Physical examination may reveal the presence of heart murmurs, and auscultation of the heart may reveal dextrocardia, which can be confirmed by radiographic studies. Family history may reveal prior heart disease in the family, but not necessarily.

• Atrial Septal Defect

  The patient had a reimplantation of the "scimitar" vein to the left atrium and closure of the inferior sinus venosus and secundum atrial septal defect. [ncbi.nlm.nih.gov]

  Presentation may be delayed in the presence of a nonrestrictive atrial septal defect until growth results in the atrial septal defect becoming restrictive causing a fall in arterial oxygen pressure (PaO 2 ). [accessanesthesiology.mhmedical.com]

  The transesophageal echocardiogram additionally revealed an ostium secundum atrial septal defect with a left-to-right shunt (Figure 1E). [revespcardiol.org]

  Echocardiography identified the scimitar vein and an atrial septal defect. [circ.ahajournals.org]

• Asymptomatic

  It was decided a close monitoring in cardiology consultation, because patient was asymptomatic, without data of pulmonary hypertension. The patient remains asymptomatic at present after completing a 7-year followup. 3. [hindawi.com]

  However, an asymptomatic course is usually observed in adult patients, in whom this syndrome may be incidentally diagnosed. [symptoma.com]

  The incidence is estimated to be 1-3 per 100,000 births, however the true incidence is unknown because the syndrome may remain undetected in asymptomatic patients. [eurorad.org]

  Survivors were asymptomatic at the long-term follow-up. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. [ncbi.nlm.nih.gov]

  In this article, 5 patients are presented to illustrate the variable presentation of this syndrome, ranging from infants who are asymptomatic to those with heart failure and severe pulmonary hypertension. [medscape.com]

• Turkish

  This single and expanded pulmonary vein is monitored in plain graphics as a shadow resembling a Turkish scimitar, extending from the mid-zone of the right lung towards the cardiophrenic angle. [oatext.com]

  Scimitar syndrome is named for the crescent- or Turkish sword-like shadow in the chest radiography and is often associated with hypoplasia of the right lung and right pulmonary artery, and dextroposition of the heart. [mesh.kib.ki.se]

  […] is a rare congenital anomaly characterized by partial anomalous pulmonary venous drainage of the right lung to the inferior vena cava (IVC) creating a tubular opacity paralleling the right cardiac border on chest radiography which resembles a curved Turkish [ncbi.nlm.nih.gov]

• Congestive Heart Failure

  Nonetheless, when associated with other cardiac defects and pulmonary arterial hypertension, there was an increased risk of congestive heart failure and mortality. [ncbi.nlm.nih.gov]

  The latter presentation is characterized by cyanosis, respiratory distress, congestive heart failure, and pulmonary artery hypertension. [childrenswi.org]

  Clinical considerations Patients with scimitar syndrome present with a wide range of signs and symptoms from cyanosis and congestive heart failure at birth to no signs or symptoms at all. [posterng.netkey.at]

  Occlusion of the anomalous systemic arteries was generally associated with clinical improvement, but congestive heart failure and pulmonary hypertension recurred in those patients with associated cardiovascular anomalies, whose condition subsequently [onlinejacc.org]

• Recurrent Respiratory Infection

  It has been reported most widely in adults and older children and is usually found during a workup for dyspnea, fatigue, recurrent respiratory infections, or as an incidental finding on a routine chest radiograph.[4,5,6] This adult form of scimitar syndrome [medscape.com]

  Rarely, the disease may manifest with a small shunt, a cardiac murmur, and recurrent respiratory infections in children and adults. [orpha.net]

  Depending on the degree of left to right intracardiac shunting and right lung hypoplasia, the patient with scimitar syndrome may present with recurrent respiratory infections and mild exertional dyspnea (older children and adults), or with severe disease [childrenswi.org]

  In older children it may present as recurrent respiratory infections or a heart murmur. On plain radiograph varying degree of right lung hypoplasia and dextroposed cardiac silhouette are seen. [ijri.org]

• Respiratory Distress

  The common clinical presentation in infancy is respiratory distress and tachypnoea due to associated pulmonary hypoplasia, pulmonary overcirculation and/or pulmonary hypertension. [ncbi.nlm.nih.gov]

  The triad of respiratory distress, right lung hypoplasia, and dextroposition of the heart should alert the clinician to the possibility of this syndrome. [medscape.com]

  In the neonatal period, the disease presents with congestive cardiac failure, most commonly due to pulmonary hypertension and respiratory distress. The right lung is most frequently involved. [orpha.net]

• Hemoptysis

  Hemoptysis and telangiectasia may be seen in hereditary hemorrhagic telangiectasia. [thoracickey.com]

  Pulmonary artery hypertension and hemoptysis both are uncommon features of this syndrome in adult life. [ncbi.nlm.nih.gov]

  The procedure brought about an improvement in right-sided hemodynamic pressures and resolution of hemoptysis. [atsjournals.org]

  The clinical spectrum of Scimitar syndrome ranges from severely ill infants to asymptomatic adults, which may present respiratory or cardiac failure, hemoptysis and pulmonary hypertension, tachypnea, chest infection, and failure to thrive. [ijp.mums.ac.ir]

  Although our patient was felt to be somewhat thin and not terribly athletic, she had only one episode of hemoptysis which may be attributable to her anomalies. [hawaii.edu]

• Respiratory Insufficiency

  Prognosis When diagnosed in infancy, the syndrome is associated with significant mortality due to severe respiratory insufficiency, cardiac failure, and pulmonary infections. [orpha.net]

  Some patients, approximately one fourth, are symptomatic in the newborn period presenting with respiratory insufficiency and/or cardiac failure. [hawaii.edu]

  Scimitar syndrome has a variable presentation such as severe respiratory insufficiency, cardiac failure [ 13 ], pulmonary hypertension, recurrent respiratory infections and heart murmur [ 6 ]. [cardiothoracicsurgery.biomedcentral.com]

• Rales

  Auscultation revealed bilateral rales and slightly suppressed respiration of the right lung. A CT chest examination was requested for evaluation. [siemens-healthineers.com]

  /crackles (consistent with effusions and/or consolidation) Congestive heart failure: Poor air entry and dullness to percussion at the bases (pleural effusion), along with basal rales/crackles (pulmonary edema) Please note that an approach to murmurs is [learn.pediatrics.ubc.ca]

• Failure to Thrive

  We report a four-year-old girl with recurrent pneumonia and failure to thrive, who was diagnosed as having scimitar syndrome. [ncbi.nlm.nih.gov]

  Failure to thrive, cyanosis, tachycardia, signs and symptoms of right ventricular failure. [accessanesthesiology.mhmedical.com]

  The clinical spectrum of Scimitar syndrome ranges from severely ill infants to asymptomatic adults, which may present respiratory or cardiac failure, hemoptysis and pulmonary hypertension, tachypnea, chest infection, and failure to thrive. [ijp.mums.ac.ir]

  Severe obstruction : Cyanosis, respiratory distress, tachypnea Symptoms can appear early after birth Prominent S2, low blood pressure and diminished pulses, hepatomegaly Can lead to right heart failure Unobstructed : Tachypnea, poor feeding, failure to [pedclerk.bsd.uchicago.edu]

• Diarrhea

  She did have some intermittent crampy abdominal pain for three days previous but had an increased appetite, attended school and had no vomiting or diarrhea. There is no history of ill contacts, unusual ingestions, trauma, bleeding or bruising. [hawaii.edu]

• Heart Disease

  Physical examination may reveal the presence of heart murmurs, and auscultation of the heart may reveal dextrocardia, which can be confirmed by radiographic studies. Family history may reveal prior heart disease in the family, but not necessarily. [symptoma.com]

  J Thorac Cardiovasc Surg 2003;125(2):238-45. v t e Circulatory system pathology ( I, 390-459 ) Hypertension Hypertensive heart disease - Hypertensive nephropathy - Secondary hypertension ( Renovascular hypertension ) Ischaemic heart disease Angina pectoris [wikidoc.org]

  Presentation in infancy is rare but can occur in those infants with concomitant congenital heart disease. [eurorad.org]

  Scimitar syndrome is a relatively rare variety of congenital heart disease characterized by partial or complete anomalous pulmonary venous connection of the right lung into the inferior vena cava. [ncbi.nlm.nih.gov]

• Heart Failure

  Thirty-three patients (75%) had an isolated form; 11 patients (25%) had associated congenital heart diseases. Twenty-two patients (50%) were symptomatic at diagnosis, including respiratory symptoms (n=20) and congestive heart failure (n=6). [ncbi.nlm.nih.gov]

  On the other hand, a symptomatic and often more severe course is observed in infants, with symptoms of heart failure, tachypnea, tachycardia, and sometimes hemoptysis. [symptoma.com]

  Adult patients usually have a benign clinical course; however, they may develop heart failure or repeated respiratory infections. [hindawi.com]

  left-to-right shunt - absence of pulmonary hypoplasia with sequestration: real systemic arterio-venous fistula with risk of heart failure. [sites.uclouvain.be]

  The latter presentation is characterized by cyanosis, respiratory distress, congestive heart failure, and pulmonary artery hypertension. [childrenswi.org]

• Vertigo

  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. [ncbi.nlm.nih.gov]

Scimitar syndrome is diagnosed through radiographic findings, most commonly through the presence of characteristic "Scimitar sign" (A curved Turkish sword) on plain chest X-rays, which describes the shadow created by the right pulmonary vein as it descends toward the cardiophrenic angle, and drains into the inferior vena cava [11]. To confirm the diagnosis, echocardiography may be performed, or a CT scan may be done. Magnetic resonance imaging (MRI) may also provide a good view into the vascular anatomy of the mediastinum, as well as angiography, but angiography is an invasive procedure and is reserved only if the mentioned methods do not provide sufficient data.

Fetal echocardiography will usually reveal the presence of anomalous venous drainage during pregnancy, and treatment strategies may be discussed early on to decide on optimal treatment.

• Scimitar Sign

  The 'scimitar sign' on plain chest radiograph is most commonly attributed to the presence of a scimitar vein, which is a variant of partial anomalous pulmonary venous drainage (PAPVD). [ncbi.nlm.nih.gov]

  Scimitar sign with normal pulmonary venous drainage and anomalous inferior vena cava. Thorax. 43(8):651-2, 1988 Aug. [rwjms1.umdnj.edu]

• Mediastinal Shift

  Therefore, only cases with a pronounced mediastinal shift to the right are usually detected prenatally. [mdpi.com]

  Mediastinal shift and dextroposition of the heart on plain film are indicators of pulmonary hypoplasia, which warrants further investigation. [sajr.org.za]

  Patient Data Age: 2 days Gender: Male From the case: Scimitar syndrome x-ray Frontal Mediastinal shift to the right with near white-out of the right hemithorax. From the case: Scimitar syndrome ct Loading images... [radiopaedia.org]

  Mediastinal shift to the right with dextroversion of the heart. [slideshare.net]

• Cardiac Catheterization Abnormal

  The diagnosis can be somewhat difficult to make, and may require cardiac catheterization. Abnormal cardiac rhythm is another late complication of total anomalous pulmonary venous return, but is also rare. [cincinnatichildrens.org]

Surgery is the treatment of choice for patients with Scimitar syndrome, especially for those who have symptomatic and severe forms of the disease, such as those with severe left-to-right shunting, pulmonary hypertension, and signs of heart failure [12].

For patients in whom the anomalous venous drainage is small and partial, no therapy is required, as the heart is able to compensate these changes. On the other hand, for patients in whom development of complete anomalous drainage occurs, surgical therapy is necessary. The principal mechanism of surgical treatment is to somehow reestablish delivery of blood from the right lung into the left atrium, either through re-implanting the pulmonary vein into the left atrium, or creating an inter-atrial baffle, so that pulmonary venous circulation into the left atrium can be restored. Ligation of the vessel is also sometimes performed, but it is important to mention that all surgical procedures carry a significant risk, since patients in whom these procedures are performed have accompanying factors which further complicate treatment, such as pulmonary hypertension, hemodynamic instability, while other accompanying congenital heart defects also cause further issues.

The prognosis depends on the severity of disease and its presentation. Patients who are asymptomatic usually have a better prognosis with proper treatment, while infants who present with symptoms of the disease require extensive surgical treatment, and this syndrome is potentially fatal when presenting in severe forms [7]. Surgical procedures in infants carry a high mortality rate [8] [9], and treatment is further complicated by the presence of other accompanying defects.

When this disorder is diagnosed early, prompt surgical intervention may significantly benefit, and provide better outcomes, which is why an early diagnosis is vital in having a good prognosis.

The exact cause of Scimitar syndrome is not known, but a genetic component has been implied since some cases have occurred in patients with a positive family history of cardiopulmonary disorders.

Scimitar syndrome is a rare occurrence, and its incidence rate is approximately 1 to 3 per 100 000 live births [4]. However, the actual number of cases is speculated to be higher, since a significant number of patients are asymptomatic, and are yet to be diagnosed.

Under physiological circumstances, the left atrium receives oxygen-rich blood from the left and right pulmonary veins, and this blood is then pumped by the left ventricle into systemic circulation. In patients with Scimitar syndrome, the left atrium receives either partially or no blood at all from the right lung, because of the right pulmonary vein, which is responsible for bringing oxygen-rich blood into the left atrium, drains into the inferior vena cava, or sometimes into the right atrium and even the portal vein. Other associated conditions include hypoplasia of the right lung, dextrocardia, as well as several forms of congenital heart disease, such as atrial septal defect (ASD), ventricular septal defect (VSD), tetralogy of Fallot, and others [5].

From a functional point of view, this syndrome behaves as a left-to-right shunt, which implies a possible asymptomatic course, but infants often have severe forms of the disease with heart failure and development of pulmonary hypertension [6].

Having in mind the fact that the cause of Scimitar syndrome is not known, and that little is understood about the pathogenesis of this disorder, prevention strategies do not currently exist. Genetic counseling has been suggested to patients with congenital heart disease, and to those who already have Scimitar syndrome.

Scimitar syndrome is characterized by anomalous venous drainage of the right lung, usually into the right atrium or the inferior vena cava, rather than the left atrium [1], and this abnormal venous drainage may be either partial or total. The name is derived from a "Scimitar-like" appearance of the pulmonary vein that drains into the inferior vena cava on chest X-rays. Other accompanying disorders include hypoplasia of the right lung, dextrocardia, and deranged systemic circulation [2]. The cause is unknown, and it is uncertain why does this syndrome occur exclusively on the right side. This disorder is rarely observed, with incidence rates of 1 to 3 per 100,000 live births. The clinical presentation may vary from asymptomatic and present as an incidental finding, which is more commonly observed in adults, to possibly life-threatening heart failure and pulmonary hypertension [3], which is usually the case in infants, and necessitates rapid treatment. A significant number of patients who present with symptoms during childhood have accompanying congenital heart disease, most common being an atrial septal defect (ASD). The diagnosis is made using radiographic techniques, including echocardiography and computed tomography (CT) as the primary choices, and treatment is aimed at correcting the anatomical anomaly through various surgical procedures.

Scimitar syndrome is a condition in which the part of the circulation which is responsible for delivering oxygen-rich blood into the heart is not properly connected. Namely, the blood vessel of the right lung, which should carry blood filled with oxygen from the lungs into the heart, specifically into the left atrium, from where the blood travels into the left ventricle, and into the systemic circulation through the aorta, instead carry blood into other sites, such as the right atrium. This abnormal drainage may be either partial (meaning only a fraction of blood follows the unusual course) or total, and as a result, there is less oxygenated blood available for the heart to pump it into the body, which can sometimes lead to heart failure and pulmonary hypertension, and is life-threatening if left untreated.

It is not known how or why this syndrome occurs, and it is rarely encountered, about 1 to 3 cases per 100 000 live births, and these patients usually have some additional conditions, such as dextrocardia (the heart is situated on the right side, instead of the left), an underdeveloped right lung, or they may have some form of congenital heart disease, most commonly atrial septal defect.

It is important to distinguish two forms of disease - asymptomatic, which is usually observed in adults, who present without complaints, and in whom the diagnosis is made incidentally, and symptomatic (and usually severe) form, which is encountered in infants in most cases, as their condition severely impairs the circulatory system from birth. The diagnosis can be made on chest X-rays, where a Scimitar-like (derived from a curved Turkish sword Scimitar) finding of the pulmonary vein can be observed, while echocardiography, computed tomography (CT scan), or magnetic resonance imaging, may provide a definite diagnosis.

Treatment includes surgical repair of the anomaly, and the principle is to reestablish normal circulation of the right lung and the heart, although these techniques carry a significant risk, especially in infants who have severe forms of the disease.

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