Eisenmenger’s syndrome pathophysiology: Difference between revisions
| Line 11: | Line 11: | ||
=== Pathogenesis === | === Pathogenesis === | ||
** Size of left to right shunt | * Eisenmenger's syndrome can develop in many types of [[Congenital heart disease|congenital heart diseases]]. | ||
* It has been found that among all the congenital heart defects, [[ventricular septal defect]] most frequently develops Eisenmenger's syndrome followed by [[atrial septal defect]] and [[patent ductus arteriosus]]<ref name="pmid7960265">{{cite journal| author=Saha A, Balakrishnan KG, Jaiswal PK, Venkitachalam CG, Tharakan J, Titus T et al.| title=Prognosis for patients with Eisenmenger syndrome of various aetiology. | journal=Int J Cardiol | year= 1994 | volume= 45 | issue= 3 | pages= 199-207 | pmid=7960265 | doi= | pmc= | url= }} </ref>. | |||
* The progression of a heart defect to Eisenmenger's syndrome depends on: | |||
** Size of left to right [[Shunt (medical)|shunt]] | |||
** Severity of pulmonary vascular disease. | ** Severity of pulmonary vascular disease. | ||
** Type of defect (it develops more frequently in uncorrected ventricular septal defect compared to atrial septal defect)<ref name="pmid12371012">{{cite journal| author=Granton JT, Rabinovitch M| title=Pulmonary arterial hypertension in congenital heart disease. | journal=Cardiol Clin | year= 2002 | volume= 20 | issue= 3 | pages= 441-57, vii | pmid=12371012 | doi= | pmc= | url= }} </ref> The left-to-right shunting causes an increase in pulmonary vascular flow. The increased pulmonary resistance in turn causes the development of pulmonary artery hypertension. This leads to reversal of shunt(right-to-left,(Qp:Qs <1 | ** Type of defect (it develops more frequently in uncorrected [[ventricular septal defect]] compared to [[atrial septal defect]])<ref name="pmid12371012">{{cite journal| author=Granton JT, Rabinovitch M| title=Pulmonary arterial hypertension in congenital heart disease. | journal=Cardiol Clin | year= 2002 | volume= 20 | issue= 3 | pages= 441-57, vii | pmid=12371012 | doi= | pmc= | url= }} </ref> | ||
The left-to-right shunting causes an increase in pulmonary vascular flow. The increased pulmonary resistance in turn causes the development of [[Pulmonary hypertension|pulmonary artery hypertension]]. This leads to reversal of shunt (right-to-left,(Qp:Qs <1) and development of [[cyanosis]] in the patient. The left side of the heart supplies to the whole body, and as a result has higher pressures than the right side, which supplies only deoxygenated blood to the lungs. If a large anatomic defect exists between the sides of the heart, blood will flow from the left side to the right side. This results in high blood flow and pressure travelling through the lungs. The increased pressure causes damage to delicate capillaries, which then are replaced with scar tissue. Scar tissue does not contribute to oxygen transfer, therefore decreasing the useful volume of the pulmonary vasculature. The scar tissue also provides less flexibility than normal lung tissue, causing further increases in blood pressure, and the heart must pump harder to continue supplying the lungs, leading to damage of more capillaries. The reduction in oxygen transfer reduces [[oxygen saturation]] in the blood, leading to increased production of red blood cells in an attempt to bring the oxygen saturation up. The excess of red blood cells is called [[polycythemia]]. Desperate for enough circulating oxygen, the body begins to dump immature red cells into the blood stream. Immature red cells are not as efficient at carrying oxygen as mature red cells, and they are less flexible, less able to easily squeeze through tiny capillaries in the lungs, and so contribute to death of pulmonary capillary beds. The increase in red blood cells also causes [[hyperviscosity syndrome]]. A person with Eisenmenger's Syndrome is paradoxically subject to the possibility of both uncontrolled bleeding due to damaged capillaries and high pressure, and random clots due to hyperviscosity and [[stasis (medicine)|stasis]] of blood. The rough places in the heart lining at the site of the septal defects/shunts tend to gather platelets and keep them out of circulation, and may be the source of random clots. Eventually, due to increased resistance, pulmonary pressures may increase sufficiently to cause a reversal of blood flow, so blood begins to travel from the right side of the heart to the left side, and the body is supplied with deoxygenated blood, leading to [[cyanosis]] and resultant organ damage. | |||
== Genetics == | == Genetics == | ||
Revision as of 05:06, 10 January 2020
|
Eisenmenger’s syndrome Microchapters |
|
Diagnosis |
|---|
|
Eisenmenger’s syndrome ACC/AHA Guidelines for Evaluation of Patients |
|
Treatment |
|
Eisenmenger’s syndrome pathophysiology On the Web |
|
American Roentgen Ray Society Images of Eisenmenger’s syndrome pathophysiology |
|
Risk calculators and risk factors for Eisenmenger’s syndrome pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Abdelrahman Ibrahim Abushouk, MD[2]
Overview
Pathophysiology
Physiology
The normal physiology of [name of process] can be understood as follows:
Pathogenesis
- Eisenmenger's syndrome can develop in many types of congenital heart diseases.
- It has been found that among all the congenital heart defects, ventricular septal defect most frequently develops Eisenmenger's syndrome followed by atrial septal defect and patent ductus arteriosus[1].
- The progression of a heart defect to Eisenmenger's syndrome depends on:
- Size of left to right shunt
- Severity of pulmonary vascular disease.
- Type of defect (it develops more frequently in uncorrected ventricular septal defect compared to atrial septal defect)[2]
The left-to-right shunting causes an increase in pulmonary vascular flow. The increased pulmonary resistance in turn causes the development of pulmonary artery hypertension. This leads to reversal of shunt (right-to-left,(Qp:Qs <1) and development of cyanosis in the patient. The left side of the heart supplies to the whole body, and as a result has higher pressures than the right side, which supplies only deoxygenated blood to the lungs. If a large anatomic defect exists between the sides of the heart, blood will flow from the left side to the right side. This results in high blood flow and pressure travelling through the lungs. The increased pressure causes damage to delicate capillaries, which then are replaced with scar tissue. Scar tissue does not contribute to oxygen transfer, therefore decreasing the useful volume of the pulmonary vasculature. The scar tissue also provides less flexibility than normal lung tissue, causing further increases in blood pressure, and the heart must pump harder to continue supplying the lungs, leading to damage of more capillaries. The reduction in oxygen transfer reduces oxygen saturation in the blood, leading to increased production of red blood cells in an attempt to bring the oxygen saturation up. The excess of red blood cells is called polycythemia. Desperate for enough circulating oxygen, the body begins to dump immature red cells into the blood stream. Immature red cells are not as efficient at carrying oxygen as mature red cells, and they are less flexible, less able to easily squeeze through tiny capillaries in the lungs, and so contribute to death of pulmonary capillary beds. The increase in red blood cells also causes hyperviscosity syndrome. A person with Eisenmenger's Syndrome is paradoxically subject to the possibility of both uncontrolled bleeding due to damaged capillaries and high pressure, and random clots due to hyperviscosity and stasis of blood. The rough places in the heart lining at the site of the septal defects/shunts tend to gather platelets and keep them out of circulation, and may be the source of random clots. Eventually, due to increased resistance, pulmonary pressures may increase sufficiently to cause a reversal of blood flow, so blood begins to travel from the right side of the heart to the left side, and the body is supplied with deoxygenated blood, leading to cyanosis and resultant organ damage.
Genetics
Genes involved in the pathogenesis of [disease name] include:
- [Gene1]
- [Gene2]
- [Gene3]
Associated Conditions
Conditions associated with [disease name] include:
- [Condition 1]
- [Condition 2]
- [Condition 3]
Gross Pathology
On gross pathology, [feature1], [feature2], and [feature3] are characteristic findings of [disease name].
Microscopic Pathology
On microscopic histopathological analysis, [feature1], [feature2], and [feature3] are characteristic findings of [disease name].
References
- ↑ Saha A, Balakrishnan KG, Jaiswal PK, Venkitachalam CG, Tharakan J, Titus T; et al. (1994). "Prognosis for patients with Eisenmenger syndrome of various aetiology". Int J Cardiol. 45 (3): 199–207. PMID 7960265.
- ↑ Granton JT, Rabinovitch M (2002). "Pulmonary arterial hypertension in congenital heart disease". Cardiol Clin. 20 (3): 441–57, vii. PMID 12371012.