A pericardial cyst is an uncommon benign dilatation of the pericardial sac surrounding the heart. It can lead to symptoms by compressing nearby structures, but is usually asymptomatic. [1] Pericardial cysts can be congenital or acquired, and they are typically diagnosed with radiologic imaging. [1] [2] [3] Management of pericardial cysts can include follow-up imaging, percutaneous aspiration, or surgical resection. [1] [2] [3]
Pericardial cysts most often are asymptomatic, with 50 to 75% of patients experiencing no symptoms. [1] [2] The presentation of symptomatic cysts depends on the cyst location and effects on nearby structures, including the heart, lungs, and esophagus. [2] [3] Symptoms can include chest pain, cough, shortness of breath, palpitations, syncope, recurrent pneumonia, congestive heart failure, difficulty swallowing, and weight loss. [1] [2] [3]
Pericardial cysts can be congenital or acquired, with the majority being congenital. [2] [3] Congenital pericardial cysts happen due to an abnormality in the development of the pericardial sac that creates a bulge which is walled off to form a cyst. [1] [3] Acquired pericardial cysts can be caused by inflammation from surgery, pericarditis, trauma, echinococcosis, tuberculosis, metastasis, or hemodialysis. [2] [3] The inflammation can lead to a walled-off pocket of fluid that is a pericardial cyst. [3]
Since pericardial cysts are often asymptomatic, the most common diagnosis is through incidental finding on a chest x-ray. [1] [2] Differentiation of pericardial cysts from diverticula is usually impossible as both the lesions have similar radiological appearance. The lone differentiating feature is the presence of communicating tract between pericardium and the cyst cavity in the diverticula, unlike the fully walled off pericardial cyst. [4] [5] When patients have symptoms, transthoracic echocardiogram is one of the first tests used to look for a pericardial cyst. [3] CT or MRI may also be used to diagnose pericardial cysts. [4] [6] [7] On CT and MRI a pericardial cyst will commonly appear as a round, fluid-filled structure surrounded by thin walls. [4] [6] [7] Diagnosis of a pericardial cyst can also be made before birth using ultrasound. [2]
The differential diagnosis for a suspected pericardial cyst includes a bronchial cyst, pericardial effusion, teratoma, lymphangioma, pericardial fat, congenital diaphragmatic hernia, neuroenteric cyst, and congenital cyst from the primitive foregut. [1] [2] [3]
Pericardial cysts that are small and cause no symptoms can be followed with repeat imaging through echocardiogram, CT, or MRI to assess for changes. [1] [2] Pericardial cysts that are large or cause symptoms may be candidates for percutaneous aspiration, ethanol sclerosis, or surgery. [1] [2] [3] Percutaneous aspiration removes the fluid from inside the cyst, and ethanol sclerosis uses the injection of ethanol into the cyst after aspiration to decrease the likelihood of cyst recurrence. [2] [3] Percutaneous aspiration with ethanol sclerosis is typically the first treatment for pericardial cyst that requires management. [2] [3] Surgery can remove a pericardial cyst through a thoracotomy, sternotomy, mediastinoscopy, or video-assisted thoracic surgery. [1] [2] The type of surgery is chosen based on the size and location of the pericardial cyst. [2]
With most pericardial cysts having no symptoms, the prognosis is very good. [1] The cysts can resolve without intervention. [1] [3] If percutaneous aspiration is performed, the recurrence rate of pericardial cysts is about 30-33%. [1] [3] Although pericardial cysts are benign, the location of cysts can rarely cause life-threatening emergencies by compressing the heart or lungs. [1] [2]
Pericardial cysts have an incidence of 1 in 100,000. [2] [7] Pericardial cysts make up 6-7% of all mediastinal masses. [2] [3] They can present at any age, but are most commonly diagnosed between the third and fifth decade of life. [2] [3] Females and males have approximately equal incidences of pericardial cysts. [2]
Pericardial cysts were first reported on during autopsies in the 19th century by pathologists. [2] [8] As the field of radiology progressed, pericardial cysts could be identified in living patients. [2] [8] In 1931, the first surgical resection of a pericardial cyst was performed by Otto Pickhardt at Lenox Hill Hospital in New York using a thoracoscopy. [2] [8] In 1943, Greenfield and his colleagues coined the term "spring water cysts" for pericardial cysts since the cysts contain clear fluid. [2] [8]
The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong inelastic connective tissue, and an inner layer made of serous membrane. It encloses the pericardial cavity, which contains pericardial fluid, and defines the middle mediastinum. It separates the heart from interference of other structures, protects it against infection and blunt trauma, and lubricates the heart's movements.
Cardiac tamponade, also known as pericardial tamponade, is a compression of the heart due to pericardial effusion. Onset may be rapid or gradual. Symptoms typically include those of obstructive shock including shortness of breath, weakness, lightheadedness, and cough. Other symptoms may relate to the underlying cause.
Pericarditis is inflammation of the pericardium, the fibrous sac surrounding the heart. Symptoms typically include sudden onset of sharp chest pain, which may also be felt in the shoulders, neck, or back. The pain is typically less severe when sitting up and more severe when lying down or breathing deeply. Other symptoms of pericarditis can include fever, weakness, palpitations, and shortness of breath. The onset of symptoms can occasionally be gradual rather than sudden.
Aneurysm of the aortic sinus, also known as the sinus of Valsalva, is a rare abnormality of the aorta, the largest artery in the body. The aorta normally has three small pouches that sit directly above the aortic valve, and an aneurysm of one of these sinuses is a thin-walled swelling. Aneurysms may affect the right (65–85%), non-coronary (10–30%), or rarely the left coronary sinus. These aneurysms may not cause any symptoms but if large can cause shortness of breath, palpitations or blackouts. Aortic sinus aneurysms can burst or rupture into adjacent cardiac chambers, which can lead to heart failure if untreated.
In medicine or biology, a diverticulum is an outpouching of a hollow structure in the body. Depending upon which layers of the structure are involved, diverticula are described as being either true or false.
A chylothorax is an abnormal accumulation of chyle, a type of lipid-rich lymph, in the space surrounding the lung. The lymphatics of the digestive system normally returns lipids absorbed from the small bowel via the thoracic duct, which ascends behind the esophagus to drain into the left brachiocephalic vein. If normal thoracic duct drainage is disrupted, either due to obstruction or rupture, chyle can leak and accumulate within the negative-pressured pleural space. In people on a normal diet, this fluid collection can sometimes be identified by its turbid, milky white appearance, since chyle contains emulsified triglycerides.
A pericardial effusion is an abnormal accumulation of fluid in the pericardial cavity. The pericardium is a two-part membrane surrounding the heart: the outer fibrous connective membrane and an inner two-layered serous membrane. The two layers of the serous membrane enclose the pericardial cavity between them. This pericardial space contains a small amount of pericardial fluid, normally 15-50 mL in volume. The pericardium, specifically the pericardial fluid provides lubrication, maintains the anatomic position of the heart in the chest, and also serves as a barrier to protect the heart from infection and inflammation in adjacent tissues and organs.
Angiomyolipomas are the most common benign tumour of the kidney. Although regarded as benign, angiomyolipomas may grow such that kidney function is impaired or the blood vessels may dilate and burst, leading to bleeding.
Lymphangiomatosis is a condition where a lymphangioma is not present in a single localised mass, but in a widespread or multifocal manner. It is a rare type of tumor which results from an abnormal development of the lymphatic system.
Primary tumors of the heart are extremely rare tumors that arise from the normal tissues that make up the heart. The incidence of primary cardiac tumors has been found to be approximately 0.02%. This is in contrast to secondary tumors of the heart, which are typically either metastatic from another part of the body, or infiltrate the heart via direct extension from the surrounding tissues. Metastatic tumors to the heart are about 20 times more common than primary cardiac tumors.
Pneumopericardium is a medical condition where air enters the pericardial cavity. This condition has been recognized in preterm neonates, in which it is associated with severe lung pathology, after vigorous resuscitation, or in the presence of assisted ventilation. This is a serious complication, which if untreated may lead to cardiac tamponade and death. Pneumomediastinum, which is the presence of air in the mediastinum, may mimic and also coexist with pneumopericardium.
Obstructive shock is one of the four types of shock, caused by a physical obstruction in the flow of blood. Obstruction can occur at the level of the great vessels or the heart itself. Causes include pulmonary embolism, cardiac tamponade, and tension pneumothorax. These are all life-threatening. Symptoms may include shortness of breath, weakness, or altered mental status. Low blood pressure and tachycardia are often seen in shock. Other symptoms depend on the underlying cause.
Congenital stenosis of vena cava is a congenital anomaly in which the superior vena cava or inferior vena cava has an aberrant interruption or coarctation.
Tarlov cysts, are type II innervated meningeal cysts, cerebrospinal-fluid-filled (CSF) sacs most frequently located in the spinal canal of the sacral region of the spinal cord (S1–S5) and much less often in the cervical, thoracic or lumbar spine. They can be distinguished from other meningeal cysts by their nerve-fiber-filled walls. Tarlov cysts are defined as cysts formed within the nerve-root sheath at the dorsal root ganglion. The etiology of these cysts is not well understood; some current theories explaining this phenomenon have not yet been tested or challenged but include increased pressure in CSF, filling of congenital cysts with one-way valves, inflammation in response to trauma and disease. They are named for American neurosurgeon Isadore Tarlov, who described them in 1938.
Theca lutein cyst is a type of bilateral functional ovarian cyst filled with clear, straw-colored fluid. These cysts result from exaggerated physiological stimulation due to elevated levels of beta-human chorionic gonadotropin (beta-hCG) or hypersensitivity to beta-hCG. On ultrasound and MRI, theca lutein cysts appear in multiples on ovaries that are enlarged.
Cardiac fibroma, also known as cardiac fibromatosis, cardiac fibrous hamartoma, fibroelastic hamartoma of heart and fibroma of heart is the second highest type of primary cardiac tumor seen in infants and children. This benign tumor made by connective tissue and fibroblast is largely observed in the ventricles of the heart. The left ventricle is the most common location of cardiac fibroma and accounts for approximately 57% of cardiac fibroma cases followed by the right ventricle with 27.5% of cases. Symptoms of the disease depend on the size of the tumor, its location relative to the conduction system, and whether it obstructs blood flow. Two-thirds of children with this tumor are asymptomatic, showing no signs and symptoms. Therefore the cause of cardiac fibroma is unexplained but has been associated with Gorlin Syndrome. Echocardiography is the primarily diagnostic method used to detect if an individual has cardiac fibroma. Resection of the tumor is recommended however heart transplantation is done if surgery is not possible. Overall prognosis of resection is favorable and the chance of recurrence is scarcely reported.
Ectopic thymus is a condition where thymus tissue is found in an abnormal location. It usually does not cause symptoms, but may leads to a mass in the neck that may compress the trachea and the esophagus. It is thought to be the result of either a failure of descent or a failure of involution of normal thymus tissue. It may be diagnosed with radiology, such as an ultrasound or magnetic resonance imaging. If it causes illness, surgery can be used to remove it. Recurrence after surgery is very unlikely.
A urethral diverticulum is a condition where the urethra or the periurethral glands push into the connective tissue layers (fascia) that surround it.
Radiologically isolated syndrome (RIS) is a clinical situation in which a person has white matter lesions suggestive of multiple sclerosis (MS), as shown on an MRI scan that was done for reasons unrelated to MS symptoms. The nerve lesions in these people show dissemination in space with an otherwise normal neurological examination and without historical accounts of typical MS symptoms.
A biloma is a circumscribed abdominal collection of bile outside the biliary tree. It occurs when there is excess bile in the abdominal cavity. It can occur during or after a bile leak. There is an increased chance of a person developing biloma after having a gallbladder removal surgery, known as laparoscopic cholecystectomy. This procedure can be complicated by biloma with incidence of 0.3–2%. Other causes are liver biopsy, abdominal trauma, and, rarely, spontaneous perforation. The formation of biloma does not occur frequently. Biliary fistulas are also caused by injury to the bile duct and can result in the formation of bile leaks. Biliary fistulas are abnormal communications between organs and the biliary tract. Once diagnosed, they usually require drainage. The term "biloma" was first coined in 1979 by Gould and Patel. They discovered it in a case with extrahepatic bile leakage. The cause of this was trauma to the upper right quadrant of the abdomen. Originally, biloma was described as an "encapsulated collection" of extrahepatic bile. Biloma is now described as extrabiliary collections of bile that can be either intrahepatic or extrahepatic. The most common cause of biloma is trauma to the liver. There are other causes such as abdominal surgery, endoscopic surgery and percutaneous catheter drainage. Injury and abdominal trauma can cause damage to the biliary tree. The biliary tree is a system of vessels that direct secreations from the liver, gallbladder, and pancreas through a series of ducts into the duodenum. This can result in a bile leak which is a common cause of the formation of biloma. It is possible for biloma to be associated with mortality, though it is not common. Bile leaks occur in about one percent of causes.