Lev's disease
| Lev's disease | |
|---|---|
| Other names | Lenegre–Lev syndrome |
 | |
| Pacemaker used for treatment of Lev's disease | |
| Specialty | Cardiology |
Lev's disease, also known as Lenegre disease, is an idiopathic disease that can result in a complete heart block, or an extremely slowed heart rate, in patients with this condition. It is thought that for certain patients, this impairment of heart's electrical conduction system is due to fibrosis and calcification of conduction cells. This disease is considered to be age related, with increasing decline seen in elderly patients.
One form has been associated with mutations in the gene that encodes SCN5A.[1]
The use of electrocardiograms, especially in non-specialized settings like emergency rooms, may incidentally reveal a dysrhythmia that can confuse diagnosis, however serial ECGs will demonstrate an evolving conduction block arrhythmia characteristic of Lev’s disease, thus allowing for correct diagnosis.[2]
Presentation
[edit]Signs and symptoms
[edit]Associated conditions
[edit]Stokes–Adams attacks can be precipitated by this condition. These involve a temporary loss of consciousness resulting from marked slowing of the heart when the atrial impulse is no longer conducted to the ventricles. This should not be confused with the catastrophic loss of heartbeat seen with ventricular fibrillation or asystole.[citation needed]
History
[edit]In March 1954, researchers Richman and Wolff analyzed several patient cases using electrocardiograms and vectorcardiograms.[3] In terms of the different cardiovascular diagnostic tests available, electrocardiograms are the most widely used between physicians.[4] Many providers prefer the use of electrocardiograms since the process of interpreting vectorcardiograms are more complex and are more labor intensive as it requires more electrode placement on patients.[5] Electrocardiograms record and detect the electrical impulses generated by the heart.[5] By doing so, medical professionals are able to analyze the electrical activity of the heart and detect any irregularities that may impact the function of the heart.[5] However, vectorcardiogram diagnostic tests operate differently from electrocardiograms.[5] This vectorcardiogram method analyzes the transverse, sagittal, and frontal planes to measure the electrical activity of the heart.[5] This diagnostic test examines different factors such as rotations, contours, and the direction of the cardiac axis of the heart.[5] Although the use of electrocardiograms are commonly used in clinical settings by many providers, vectorcardiograms are able to be more precise due to it's ability to detect and identify the location of myocardial infarction, cardiac blockage, and hypertrophy.[5] Among cases studied, patients exhibited a left bundle branch block that resembled a right bundle branch block.[3] In comparison however, although the electrocardiograms showed a right bundle branch block, the vectorcardiograms detected a left bundle branch block in the patient.[3]
In March 1964, Jean Lenègre published a paper discussing the pathology behind the gradual damage and scarring of the ventricular conduction system.[6]
In November 1964, Maurice Lev published a paper with similar findings as Lenègre where he saw the degenerative processes of the ventricular conduction system associated with calcification in older patient populations. Lev focused primarily on the anatomical process leading to atrioventricular blocks in patients and was able to build off the research conducted by Lenègre.[7]
Epidemiology
[edit]![[icon]](/wiki/File:Wiki_letter_w_cropped.svg){kind=small} | This section is empty. You can help by adding to it. (July 2024) |
Pathophysiology
[edit]Lev's disease operates similarly to other atrioventricular (AV) conduction disturbances. Unfortunately, the specific mechanisms of this condition are not yet fully clear. However, it is suspected that like other AV conduction disorders, Lev's disease can occur via two ways, acquired or congenital.[8] Individuals with congenital Lev's disease typically come from pregnancies with lupus erthematosus complications or transfer of SSA/Ro and SSB/LA antibodies.[8] In contrast, there are many theories on how Lev's disease may be aquired by a patient, however, there is strong evidence of fibrosis of the conduction system leading to impairments of the conduction system.
The heart is composed of two primary types of cell, contractile cells and specific cells that carry out conduction roles, including directing the actions of contractile cells.[9] In the case of Lev's disease, calcification or fibrosis of these cells will impact their ability to work optimally, hindering the propagation of electrical currents through the heart.
Diagnosis
[edit] | This section is empty. You can help by adding to it. (July 2024) |
Prevention
[edit]Lev's disease remains an area of ongoing research and the specific underlying mechanisms of this disease state are not fully understood. As a result, effective prevention methods are currently limited.
Researchers do understand that Lev's disease can be presented in two primary forms: acquired and congenital. Individuals who have acquired Lev's disease presents signs and symptoms later in life and are often linked to the use of medication, medical conditions, surgical procedures, or environmental factors. In cases of congenital Lev's disease, it is present from birth and is commonly caused by genetic or developmental factors.[10] Depending if the patient has acquired or congenital Lev's disease, the prevention strategies may differ and vary to address the needs associated with each form.
A preventive strategy can involve regular electrocardiogram tests, especially if the individual has a genetic family history of cardiac conditions such as Lev's disease.[11] Additionally, the use of certain medications can impact the conduction of the heart.[10] Studies have shown that medications such as Digoxin, beta blockers, calcium channel blockers, and anti-arrhythmic medications can slow down heart conduction in patients with pre-existing cardiac conditions.[10] Since other cardiac conditions can be associated with Lev's disease, it is important to promote a heart healthy lifestyle.[12] This includes adopting dietary and lifestyle changes that support and promote healthy heart health.[12]
Treatment and management
[edit]Lev's disease is also known as Progressive cardiac conduction defect (PCCD)[1]
There are no studies that were conducted to determine what is the best treatment option for Lev's disease. However, this disease is typically treated with a pacemaker[13][14]
Case studies
[edit]Genetic testing
[edit]Over the years, many clinical studies have been conducted to give insight on the congenital acquirement of Lev's Disease, particularly to answer the question of if there is a genetic component that puts patients at a predisposed risk. A mouse model studied mice with a heterogenous mutation to their SCN5a gene, which impacts the formation of Na+ channels, leaving them with myocardial conditions similar to those with Lev's disease.[15] The study used these mice to gain a further understanding into the progression of such abnormalites, and how it can be applied to the similar impacts of fibrosis and calcifcation in human myocardial systems.
See also
[edit]References
[edit]- ^ a b Schott JJ, Alshinawi C, Kyndt F, Probst V, Hoorntje TM, Hulsbeek M, et al. (September 1999). "Cardiac conduction defects associate with mutations in SCN5A". Nature Genetics. 23 (1): 20–21. doi:10.1038/12618. PMID 10471492. S2CID 7595466.
- ^ Carius BM, Long B, Schauer S (May 2019). "Lev's Syndrome: A rare case of progressive cardiac conduction disorder presenting to the emergency department". The American Journal of Emergency Medicine. 37 (5): 1006.e1–1006.e4. doi:10.1016/j.ajem.2019.01.054. PMID 30723001.
- ^ a b c Richman JL, Wolff L (March 1954). "Left bundle branch block masquerading as right bundle branch block". American Heart Journal. 47 (3): 383–393. doi:10.1016/0002-8703(54)90295-1. PMID 13124253.
- ^ Cook DA, Oh SY, Pusic MV (November 2020). "Accuracy of Physicians' Electrocardiogram Interpretations: A Systematic Review and Meta-analysis". JAMA Internal Medicine. 180 (11): 1461–1471. doi:10.1001/jamainternmed.2020.3989. PMC 7522782. PMID 32986084.
- ^ a b c d e f g Jaros R, Martinek R, Danys L (July 2019). "Comparison of Different Electrocardiography with Vectorcardiography Transformations". Sensors. 19 (14): 3072. Bibcode:2019Senso..19.3072J. doi:10.3390/s19143072. PMC 6678609. PMID 31336798.
- ^ Lenegre J (March 1964). "Etiology and pathology of bilateral bundle branch block in relation to complete heart block". Progress in Cardiovascular Diseases. 6 (5): 409–444. doi:10.1016/S0033-0620(64)80001-3. PMID 14153648.
- ^ Lev M (November 1964). "Anatomic basis for atrioventricular block". The American Journal of Medicine. 37 (5): 742–748. doi:10.1016/0002-9343(64)90022-1. PMID 14237429.
- ^ a b Wessels A, McQuinn T (2009). "Atrioventricular Conduction Disturbances". In Lang F (ed.). Encyclopedia of Molecular Mechanisms of Disease. Berlin, Heidelberg: Springer. pp. 179–181. doi:10.1007/978-3-540-29676-8_173. ISBN 978-3-540-29676-8.
- ^ Waller BF, Gering LE, Branyas NA, Slack JD (July 1993). "Anatomy, histology, and pathology of the cardiac conduction system—part V". Clinical Cardiology. 16 (7): 565–569. doi:10.1002/clc.4960160710. ISSN 0160-9289.
- ^ a b c Issa ZF, Miller JM, Zipes DP (2009-01-01), Issa ZF, Miller JM, Zipes DP (eds.), "CHAPTER 6 - Atrioventricular Conduction Abnormalities", Clinical Arrhythmology and Electrophysiology, Philadelphia: W.B. Saunders, pp. 127–142, doi:10.1016/b978-1-4160-5998-1.00009-4, ISBN 978-1-4160-5998-1, retrieved 2024-07-28
- ^ Harkness WT, Hicks M (2024), "Right Bundle Branch Block", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 29939649, retrieved 2024-07-28
- ^ a b Kaminsky LA, German C, Imboden M, Ozemek C, Peterman JE, Brubaker PH (2022-01-01). "The importance of healthy lifestyle behaviors in the prevention of cardiovascular disease". Progress in Cardiovascular Diseases. 70: 8–15. doi:10.1016/j.pcad.2021.12.001. ISSN 0033-0620.
- ^ Barra SN, Providência R, Paiva L, Nascimento J, Marques AL (November 2012). "A review on advanced atrioventricular block in young or middle-aged adults". Pacing and Clinical Electrophysiology. 35 (11): 1395–1405. doi:10.1111/j.1540-8159.2012.03489.x. PMID 22897386.
- ^ Carius BM, Long B, Schauer S (May 2019). "Lev's Syndrome: A rare case of progressive cardiac conduction disorder presenting to the emergency department". The American Journal of Emergency Medicine. 37 (5): 1006.e1–1006.e4. doi:10.1016/j.ajem.2019.01.054. PMID 30723001.
- ^ Schott JJ, Alshinawi C, Kyndt F, Probst V, Hoorntje TM, Hulsbeek M, et al. (September 1999). "Cardiac conduction defects associate with mutations in SCN5A". Nature Genetics. 23 (1): 20–21. doi:10.1038/12618. ISSN 1546-1718.