Scimitar Syndrome
What Is Scimitar Syndrome?
Scimitar Syndrome is medically defined as a rare congenital malformation of the heart and lungs, marked by displacement to the right of the heart.
To clearly understand, Scimitar syndrome is described as an anomalous pulmonary venous return wherein the right pulmonary vein is not connected to the left atrium instead it is connected in the inferior vena cava.
Historically, it is named for the crescent or Turkish sword-like shadow appeared in the chest radiography. This condition is typically correlates with hypoplasia of the right lung and right pulmonary artery and dextroposition of the heart.
Epidemiology
Since the syndrome is considered to be rare disease. Approximately 1 to 3 out of 100,000 live births are being affected by scimitar syndrome. Meanwhile, the true incidence is high because lot of patients are asymptomatic or no occurrence of symptoms at all.
Factually, it has been reported that most widely in adults and older children is usually observed during a workup for dyspnea, recurrent respiratory infection, fatigue or as an incidental findings on a routine chest radiograph.
Causes
In medical world the exact cause of scimitar syndrome is still unknown. Some medical experts believed that is undetermined phenomena during birth defect meaning children can have higher chances of developing the syndrome anytime in their lives.
It is also prevails in the family that simply suggests it is more associated with hereditary factors or passing the mutated gene to their offspring.
Signs & Symptoms
Most of the percentage of scimitar patient is asymptomatic or no occurrence of symptoms at all but for others who have it may experience;
Adults
- Rapid breathing
- Cyanosis which means an appearance of bluish color to the mucous membranes and skin as a result of lack of oxygen passing in the blood.
- Respiratory distress
- Shortness of breath
- Rib cage muscle retraction
Infant
If the infant was born to have scimitar syndrome, the symptoms will appear right away after they are born or may appear in their early childhood. And these include;
- Intense crying
- Easily becoming fatigue or exhausted
- Shortness of breath or baby will struggle for breathing
- Appearance of bluish color in their skin, extremities indication of the body is not getting enough amount of oxygen.
Diagnosis
Some similar conditions may arise that is similarly to scimitar syndrome and diagnosing accurately will eliminate some following conditions such as;
- Unilateral Absence of Pulmonary Artery or UAPA
- Arteriovenous Malformation
- Intralobar Sequestration
- Mucoid Impaction or Bronchial Atresia
- Pulmonary Sequestration
- Right Middle Lobe Atelectasis
- Pulmonary Varix
Diagnostic Approach
The severity of the scimitar syndrome is significantly differentiated. Since, this syndrome can be asymptomatic for some people the tendency is they are not aware of it until it is diagnosed. In order to examine intensively the suspected scimitar patient he or she will undergo some diagnostic testing such as;
- Chest x-ray
- Transesophageal or transthoracic echocardiography
- Angiography
- CT angiography
- MR Angiography
- MRI (Magnetic Resonance Imaging)
Treatment
Patient with symptomatic and other form of disease such as pulmonary hypertension and other signs of heart failure should undergo surgery. But for patients who are asymptomatic do not require any general treatment however they are must kept under constant observation for any signs of deterioration.
According to Prime health Channel, the major objective of surgery is to create an inter-atrial baffle in which it redirects the pulmonary venous circulation into the left atrium of the patient while other surgical operation option involves re-implanting the abnormal vein directly into the left atrium.
Furthermore, for those patients who are suffering from pulmonary hypertension that is also associated with scimitar syndrome are also required to undergo surgical management.
Finally, doctor is the decision maker in what kind of treatment is appropriate in treating the severity and nature of the symptoms along with the associated disorder. It is highly significant also to take consideration some factors like number of blood flow passing into inferior vena cava together with the degree of propelling of left going to the right.
Surgical Method
According to the paper (A New Surgical Approach to Scimitar Syndrome) published at “The Annals of Thoracic Surgery” by Ignacio Lugones and Ruben Garcia of Fundacion Favaloro University Hospital at Buenos Aires, Argentina, an outline have been made to understand the step by step process to treat scimitar syndrome and these includes;
- During the surgery, the right lung is subject for deflation by using the selective bronchial intubation with a double-lumen endotracheal tube.
- Then, the right pleural space is widely opened after the median sternotomy.
- The pulmonary venous canal is recognized. On this stage, a tiny distance between the link of the lobar branches going to the scimitar vain and its entry into the IVC of the abdominal cavity is observed.
- Followed by a careful dissection of the pulmonary veins, the pericardium or the outer lining of the heart tissue is then opened and the right pulmonary arteries are cross-clamped.
- Next is the Scimitar Vein is transected along to the level of the diaphragm and the both ends are tightly compressed with running sutures.
- After being transected the SV is longitudinally opened on its lateral aspect. Then, will be subjected for anastomosed to the right later wall of the pericardium.
- Anastomosis is the termed used to join two ducts, blood vessels, or bowel segments to allow flow from one another. During this procedure, a wide anastomosis is conducted between both incisions. However, the tension and kinking may occur therefore it must be avoided because the pericardium is mobilized to reach the scimitar vein (SV).
- Afterward, the aortic and bicaval cannulation is executed and the cardiopulmonary is implemented.
- Coming from the both vertices of the incision, the continuous sutures is running continually, attaching the pericardium to the right atrial wall.
- It is highly crucial that the superficial bites must be taken away in the inner surface of the pericardium to limit the injury to the phrenic nerve. Then, air is removed just before the suture is complete.
- Finally, the aortic clamp is detached and the patient is prevented from cardiopulmonary bypass.
Complications
The most serious and severe potential complications that may occur due to scimitar syndrome is the development of pulmonary hypertension. This is a condition wherein there is an increase of blood pressure in the pulmonary artery, veins, and capillaries that branded as lung vasculature which leads to shortness of breath, dizziness, fainting, and swelling of legs.
Reference
- http://healthh.com/scimitar-syndrome/es
- https://en.wikipedia.org/wiki/Scimitar_syndrome#Presentation
- http://www.heart-consult.com/articles/scimitar-syndrome
- http://circ.ahajournals.org/content/121/23/e434
- https://www.symptoma.com/en/info/scimitar-syndrome#treatment
- http://www.primehealthchannel.com/scimitar-syndrome.html