Cardiac amyloidosis overview
|
Cardiac amyloidosis Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Cardiac amyloidosis overview On the Web |
|
American Roentgen Ray Society Images of Cardiac amyloidosis overview |
|
Risk calculators and risk factors for Cardiac amyloidosis overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Aarti Narayan, M.B.B.S [2]; Raviteja Guddeti, M.B.B.S. [3]
Overview
Cardiac amyloidosis is a well-known progressive condition, which has been reported with varying incidence rates. It refers to extracellular deposition of light chains of some serum proteins, that assume a beta pleated structure.
Myocardial involvement results in congestive heart failure and fatal arrhythmias and is the leading cause of death in patients with amyloidosis. Systemic amyloidosis of AL and TTR type is often associated with amyloid deposition in heart valves, in addition to blood vessels and myocardium [1] [2] In this classical type of valvular amyloidosis are the deposits occur in previously unaltered valves.
There is also another type of cardiac amyloidosis restricted entirely to the heart valves (surgically removed for chronic valvular disease) or only the atria (also called isolated atrial amyloidosis). The deposits are small and restricted to the areas of scarring and calcification.[3] The amyloid protein has not been identified but it has been demonstrated not to be AL or AA [4] [5]
This condition is heavily underdiagnosed because the thickening of ventricles from extracellular deposition of amyloid material in the heart is mostly attributed to chronic hypertension, which is also a feature of cardiac amyloidosis.
Pathophysiology
The characteristic feature of cardiac amyloidosis is abnormal deposition of abnormally folded light chains of several serum proteins, making them insoluble and accumulate in various organs. This abnormal folding of proteins is most commonly a result of genetic mutations or excessive formation. Involvement of cardiac muscle can lead to heart failure, arrhythmias and advanced conduction disorders [6].
Differentiating Cardiac Amyloidosis from Other Diseases
Cardiomyopathy with congestive heart failure is the most common amyloidosis syndrome, especially in patients with no history of ischemia such as the presence of prior documented myocardial infarction or presence of coronary artery disease risk factors.[7] Cardiac amyloidosis should be included in the differential diagnoses in patients with unexplained congestive heart failure and no history of valvular disease, long-standing hypertension or ischemia.[7]
Natural History, Complications and Prognosis
The presence or absence of cardiac involvement with amyloid is the most important prognostic factor.[7] Untreated CA is associated with very high mortality rate. Most common complications include heart failure, sudden cardiac death due to electromechanical dissociation and pericardial effusion.
Diagnosis
History and Symptoms
Amyloidosis is a multi-system disease involving many organs simultaneously. Approximately more than 50% of the patients with amyloidosis present with right heart failure symptoms. The most common symptoms observed in patients with cardiac amyloidosis include fatigue, weight loss, and periorbital purpura.[8]
References
- ↑ Pomerance, A. The pathology of senile cardiac amyloidosis. J. Pathol. Bacteriol. 91, 357. 1966
- ↑ Buja, L. M., Khoi, N. B., and Roberts W. C. Clinically significant cardiac amyloidosis. Clinicopathologic findings in 15 patients. Am. J. Cardiol., 26, 394. 1970
- ↑ Goffin, Y. A. Microscopic amyloid deposits in the heart valves: a common local complication of chronic damage and scarring. J. Clin. Pathol., 33, 262. 1980
- ↑ Goffin, Y. A., Murdoch, W., Cornwell, G. G. III, and Sorenson, G. D. Microdeposits of amyloid in sclerocalcific heart valves: a histochemical and immunoflourescence study. J. Clin. Pathol., 36, 1342. 1983
- ↑ Amyloid and amyloidosis. Gilles Grateau, Robert A. Kyle, Martha Skinner, 2005 ISBN 0-8493-3534-5
- ↑ Dharmarajan K, Maurer MS (2012). "Transthyretin cardiac amyloidoses in older North Americans". Journal of the American Geriatrics Society. 60 (4): 765–74. doi:10.1111/j.1532-5415.2011.03868.x. PMC 3325376. PMID 22329529. Unknown parameter
|month=ignored (help) - ↑ 7.0 7.1 7.2 Gertz MA, Lacy MQ, Dispenzieri A (1999). "Amyloidosis: recognition, confirmation, prognosis, and therapy". Mayo Clinic Proceedings. Mayo Clinic. 74 (5): 490–4. doi:10.4065/74.5.490. PMID 10319082. Retrieved 2012-02-13. Unknown parameter
|month=ignored (help) - ↑ Kyle RA, Gertz MA (1995). "Primary systemic amyloidosis: clinical and laboratory features in 474 cases". Seminars in Hematology. 32 (1): 45–59. PMID 7878478. Unknown parameter
|month=ignored (help);|access-date=requires|url=(help)