Myxoma overview
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: Maria Fernanda Villarreal, M.D. [2]Cafer Zorkun, M.D., Ph.D. [3]Ahmad Al Maradni, M.D. [4]
Overview
A myxoma (Myxo- = Latin for mucus) is the most common primary tumor of the heart. Cardiac myxomas are usually located in either the left or right atrium of the heart; about 86 percent occur in the left atrium.[1] Myxomas are typically pedunculated, with a stalk that is attached to the interatrial septum. The most common location for attachment of the stalk is the fossa ovalis region of the interatrial septum. The phrase "myxomatous degeneration" refers to the process in which connective tissue becomes filled with mucus. About 71% of myxomas occur in the heart, 41% on the skin, and 7% in the oral cavity (usually on the palate). Common physical examination findings of cardiac myxoma include murmur and abnormal heart sounds that change when the patient changes positions. Complications that can develop as a result of myxoma are: arrhythmias, pulmonary edema, peripheral emboli, metastasis, blockage of the mitral heart valve. Surgery is the mainstay of treatment for myxomas.[2]
Historical Perspective
Cardiac myxoma was first described in 1845.[3] In 1951, Prichard described a kind of microscopic endocardial structure of the atrial septum, which was suggested to be associated with cardiac myxoma.[4] Clarence Crafoord, a Swedish cardiovascular surgeon successfully removed a cardiac myxoma for the first time in 1954.[5] Before 1951, cardiac myxoma diagnosis was made only at post-mortem examination.[6] In 1959, the first M-mode echocardiogram of a left atrial myxoma was reported.[7]
Classification
Cardiac myxomas are classified by the WHO histological classification of tumors of the heart "Benign tumors and tumor-like lesions" and categorized into a type of pluripotent mesenchymal tumor.[8][9]
Pathophysiology
Cardiac myxoma arises from remnants of subendocardial vasoformative reserve cells, which are primitive mesenchymal cells that are normally involved in the supportive structure of the endocardium.[10][11] Myxomas are usually located in the fossa ovalis and endocardium of the atrial septum
Some symptoms of myxoma may be associated with the release of interleukin 6 (IL-6).[12][13] On gross pathology, a gelatinous, irregular surface that fills the left atrium is characteristic finding of myxoma. A common hystopathological finding is the Gamna-Gandy Bodies that consist of fibrosis and deposition of iron pigments.
Causes
The main cause of cardiac myxoma remains unknown.[14][15] However, in some cases like inherited myxomatosis there is a strong relation with genetic mutations of PRKAR1A gene.
Differentiating Myxoma from other Diseases
Cardiac myxoma should be differentiated from other benign and malignant primary heart tumors including papillary fibroelastoma, lipoma, rhabdomyoma, and cardiac metastasis.[16]
Epidemiology and Demographics
Cardiac myxomas are the most common primary cardiac tumor in adults, with a reported prevalence of 0.03% in general population.[17] The incidence of cardiac myxoma is about 1/ 100,000 per year.[18] The majority of patients with cardiac myxoma are diagnosed between 30 to 60 years; children are rarely affected. Females are more commonly affected with cardiac myxoma than men. The female-to-male ratio is approximately 1.8 to 1.[17][19] Cardiac myxomas represent 78% of heart tumors.
Risk Factors
Common risk factors in the development of myxoma are female gender and genetic predisposition. In some cases, right atrial myxoma has been associated with tricuspid stenosis and atrial fibrillation.[20]
Natural History, Complications and Prognosis
If left untreated, cardiac myxoma progression occurs slowly. The overlap of various phenomena such as thrombosis, hemorrhage, or fragmentation may influence tumor growth, detachment, and consequently embolism.[21] Constitutional symptoms, such as: weight loss, fatigue, weakness are often the initial clinical onset of cardiac myxoma, and may resemble those from endocarditis. Metastases are uncommon in cardiac myxoma.
Since the majority of the cardiac myxomas are left sided, it may progress to develop mitral valve obstruction or systemic embolic events, such as stroke. Whereas, right atrial myxomas may obstruct the tricuspid valve and can present as right sided heart failure. Approximately 20% of patients with cardiac myxoma are asymptomatic. Overall, clinical features of cardiac myxoma are associated with the size of the tumor, location, size, and mobility.[22]
Diagnosis
Staging
There is no established system for the staging of myxoma.[20]
History and Symptoms
Symptoms associated with cardiac myxomas are typically due to the effect of the mass of the tumor obstructing the normal blood flow within the heart chambers. Left atrial myxoma symptoms may mimic mitral stenosis, while right atrial myxomas rarely produce symptoms until they have grown to be at least 13 cm wide.[23] General symptoms may also mimic those of infective endocarditis. [20] Cardiac myxoma symptoms may occur at any time, but most often they tend to occur with changes in body position. Common symptoms include: chest pain, palpitation, dizziness, syncope and dyspnea on exertion.
Physical Examination
There are no specific physical findings for cardiac myxoma.[24][25][26] The ascultatory presence of a "tumor plop" (which is caused by the obstruction of the mitral valve orifice by the tumor) on physical examination is highly suggestive of cardiac myxoma.[25] Common physical examination findings of cardiac myxoma include systolic or diastolic murmurs (depending on size, mobility, and location of the tumor).[25]
Laboratory Findings
Laboratory findings consistent with cardiac myxoma are generally non-specific, results often demonstrate anemia, leukocytosis and elevated erythrocyte sedimentation rate.[27]
Chest X-ray
On chest x-ray, cardiac myxoma is characterized by normal results and in some cases a calcification overlying the heart.[2]
CT Scan
On cardiac myxoma, CT scan is characterized by low attenuation and areas of dystrophic calcification in cardiac chambers.[28] CT scan may be helpful in the diagnosis of cardiac myxoma, because it provides better soft-tissue contrast than echocardiography, and it can also differentiate calcification and fat, and may allow tissue diagnosis of some masses such as lipomas.[29]
MRI
On Magnetic Resonance Imaging (MRI) or Cardiac Magenetic Resonance (CMR), cardiac myxoma is characterized by a soft tissue mass within the cardiac chambers isointense to skeletal muscle. This imaging modality, plays an important role in the evaluation of cardiac masses and is of great value when echocardiographic findings are suboptimal or when the lesion has an atypical location or appearance.[26]
Echocardiography
The echocardiogram is the initial modality and most useful diagnostic imaging study in cardiac myxoma. On cardiac ultrasound, cardiac myxoma is characterised by the presence of a heterogeneous pedunculated mass that is commonly located in the left atrium. Echocardiography allows for evaluation assessment of tumor mobility, as it often protrudes through valve flaps. As a test modality, two-dimensional echocardiography is often coupled with other modalities (such as, Doppler echocardiography) to detect vascular abnormalities that frequently occur in cardiac myxomas.[30]
Other Diagnostic Studies
Other diagnostic study for cardiac myxoma is cardiac angiography, which often demonstrates contrast media-enhanced tumor vasculature.[31]
Treatment
Medical Therapy
There is no known medical therapy for cardiac myxomas.[2]
Surgery
Surgery is the mainstay of treatment for cardiac myxoma. [32] The feasibility of surgery depends on the patient hemodynamic stability at diagnosis.[33] Cardiac myxoma surgery has an operative mortality around 0 to 3%, depending on risk factors or mechanical damage to a heart valve, as well as adhesion of the tumor to valve leaflets.[34] The short and long-term prognosis is generally regarded as excellent.
References
- ↑ Knepper LE, Biller J, Adams HP Jr, Bruno A. Neurologic manifestations of atrial myxoma. A 12-year experience and review. Stroke. 1988 Nov;19(11):1435-40. (Medline abstract)
- ↑ 2.0 2.1 2.2 Cardiac Myxoma. Dr Henry Knipe and Dr Frank Gaillard et al. Radiopaedia 2015. http://radiopaedia.org/articles/cardiac-myxoma Accessed on November 30, 2015
- ↑ King TW. On simple vascular growths in the left auricle of the heart. Lancet 1845; 2:428-9
- ↑ Amano J, Kono T, Wada Y, Zhang T, Koide N, Fujimori M, Ito K (2003). "Cardiac myxoma: its origin and tumor characteristics". Ann Thorac Cardiovasc Surg. 9 (4): 215–21. PMID 13129418.
- ↑ Chitwood WR (1992). "Clarence Crafoord and the first successful resection of a cardiac myxoma". Ann. Thorac. Surg. 54 (5): 997–8. PMID 1417305.
- ↑ PRICHARD RW (1951). "Tumors of the heart; review of the subject and report of 150 cases". AMA Arch Pathol. 51 (1): 98–128. PMID 14789340.
- ↑ Pinede L, Duhaut P, Loire R (2001). "Clinical presentation of left atrial cardiac myxoma. A series of 112 consecutive cases". Medicine (Baltimore). 80 (3): 159–72. PMID 11388092.
- ↑ Amano J, Nakayama J, Yoshimura Y, Ikeda U (2013). "Clinical classification of cardiovascular tumors and tumor-like lesions, and its incidences". Gen Thorac Cardiovasc Surg. 61 (8): 435–47. doi:10.1007/s11748-013-0214-8. PMC 3732772. PMID 23460447.
- ↑ Wold LE, Lie JT (1980). "Cardiac myxomas: a clinicopathologic profile". Am. J. Pathol. 101 (1): 219–40. PMC 1903582. PMID 7446701.
- ↑ Roscher AA, Kato NS, Quan H, Padmanabhan M (1996). "Intra-atrial myxomas, clinical-pathologic correlation based on two case studies including historical review". J Cardiovasc Surg (Torino). 37 (6 Suppl 1): 131–7. PMID 10064365.
- ↑ Acebo E, Val-Bernal JF, Gómez-Román JJ (2001). "Prichard's structures of the fossa ovalis are not histogenetically related to cardiac myxoma". Histopathology. 39 (5): 529–35. PMID 11737312.
- ↑ Seino Y, Ikeda U, Shimada K. (1993). "Increased expression of interleukin 6 mRNA in cardiac myxomas". Br Heart J. 69 (6): 565–7. PMID 8343326.
- ↑ Jourdan M, Bataille R, Seguin J, Zhang XG, Chaptal PA, Klein B (1990). "Constitutive production of interleukin-6 and immunologic features in cardiac myxomas". Arthritis Rheum. 33 (3): 398–402. PMID 1690543.
- ↑ Amano J, Kono T, Wada Y, Zhang T, Koide N, Fujimori M, Ito K (2003). "Cardiac myxoma: its origin and tumor characteristics". Ann Thorac Cardiovasc Surg. 9 (4): 215–21. PMID 13129418.
- ↑ Messina F, Romano P, Crosca S (2015). "Atrial myxomas and different clinical presentations". Int. J. Cardiol. doi:10.1016/j.ijcard.2015.08.063. PMID 26442965.
- ↑ Hartig I, Kraatz EG, Beurich HW, Moosig F (2014). "[Atrial myxoma with clinical signs of systemic inflammatory disease.]". Z Rheumatol. doi:10.1007/s00393-013-1347-y. PMID 24599357.
- ↑ 17.0 17.1 Yoon DH, Roberts W (2002). "Sex distribution in cardiac myxomas". Am. J. Cardiol. 90 (5): 563–5. PMID 12208428.
- ↑ National Cancer Institute. Physician Data Query Database 2015. http://www.cancer.gov/publications/pdp
- ↑ Grebenc ML, Rosado de Christenson ML, Burke AP, Green CE, Galvin JR (2000). "Primary cardiac and pericardial neoplasms: radiologic-pathologic correlation". Radiographics. 20 (4): 1073–103, quiz 1110–1, 1112. doi:10.1148/radiographics.20.4.g00jl081073. PMID 10903697.
- ↑ 20.0 20.1 20.2 Atrial Myxoma.Wikipedia URL https://en.wikipedia.org/wiki/Atrial_myxoma Accessed November 13, 2015
- ↑ Markel ML, Waller BF, Armstrong WF (1987). "Cardiac myxoma. A review". Medicine (Baltimore). 66 (2): 114–25. PMID 3547010.
- ↑ Burke A, Virmani R. Tumors of the Heart and Great Vessels. Amer Registry of Pathology; 1996.
- ↑ Ramchandani M (2010). "Less invasive surgery for cardiac tumors". Methodist Debakey Cardiovasc J. 6 (3): 27–31. PMID 20834208.
- ↑ Bulkley BH, Hutchins GM (1979). "Atrial myxomas: a fifty year review". Am. Heart J. 97 (5): 639–43. PMID 433739.
- ↑ 25.0 25.1 25.2 Goswami KC, Shrivastava S, Bahl VK, Saxena A, Manchanda SC, Wasir HS (1998). "Cardiac myxomas: clinical and echocardiographic profile". Int. J. Cardiol. 63 (3): 251–9. PMID 9578352.
- ↑ 26.0 26.1 Grebenc ML, Rosado-de-Christenson ML, Green CE, Burke AP, Galvin JR (2002). "Cardiac myxoma: imaging features in 83 patients". Radiographics. 22 (3): 673–89. doi:10.1148/radiographics.22.3.g02ma02673. PMID 12006696.
- ↑ Reynen K (1995). "Cardiac myxomas". N. Engl. J. Med. 333 (24): 1610–7. doi:10.1056/NEJM199512143332407. PMID 7477198.
- ↑ Schoepf UJ. CT of the Heart, Principles and Applications.Springer Science & Business Media; 2007
- ↑ Araoz PA, Eklund HE, Welch TJ, Breen JF (1999). "CT and MR imaging of primary cardiac malignancies". Radiographics. 19 (6): 1421–34. doi:10.1148/radiographics.19.6.g99no031421. PMID 10555666.
- ↑ Bentivoglio M, Savino K, Corea L, Verdecchia P, Porcellati C (1989). "[Doppler echocardiography in atrial myxoma]". Cardiologia (in Italian). 34 (9): 783–6. PMID 2605587.
- ↑ Huang CY, Yu WC, Chen KC, Lin SJ (2005). "Coronary angiography of cardiac myxoma". Clin Cardiol. 28 (11): 505–9. PMID 16450793.
- ↑ Cardiac Myxoma. Radiopedia. http://radiopaedia.org/articles/cardiac-myxoma Accessed on November 30,2015
- ↑ Berdajs DA, Ferrari E. Surgical treatment for heart myxomas. Multimed Man Cardiothorac Surg. 2012;2012:mms016.
- ↑ Jain S, Maleszewski JJ, Stephenson CR, Klarich KW (2015). "Current diagnosis and management of cardiac myxomas". Expert Rev Cardiovasc Ther. 13 (4): 369–75. doi:10.1586/14779072.2015.1024108. PMID 25797902.