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Encyclopedia > Atrial septal defect
Atrial septal defect
Heart of human embryo of about thirty-five days
ICD-10 Q211
ICD-9 745.5-745.6
OMIM 108800
DiseasesDB 1089
eMedicine med/3519
MeSH C14.240.400.560.375

Atrial septal defects (ASD) are a group of congenital heart diseases that enables communication between atria of the heart and may involve the interatrial septum. The inter-atrial septum is the tissue that separates the right and left atria from each other. Without this septum, or if there is a defect in this septum, it is possible for blood to travel from the left side of the heart to the right side of the heart, or the other way around, resulting in mixing of arterial and venous blood. Image File history File links Gray468. ... Embryos (and one tadpole) of the wrinkled frog (Rana rugosa). ... The following codes are used with International Statistical Classification of Diseases and Related Health Problems. ... // Q00-Q99 - Congenital malformations, deformations and chromosomal abnormalities (Q00-Q07) Congenital malformations of the nervous system (Q00) Anencephaly and similar malformations (Q01) Encephalocele (Q02) Microcephaly (Q03) Congenital hydrocephalus (Q04) Other congenital malformations of brain (Q05) Spina bifida (Q06) Other congenital malformations of spinal cord (Q07) Other congenital malformations of nervous... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Mendelian Inheritance in Man project is a database that catalogues all the known diseases with a genetic component, and - when possible - links them to the relevant genes in the human genome. ... The Diseases Database is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... eMedicine is an online clinical medical knowledge base that was founded in 1996. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... The heart and lungs, from an older edition of Grays Anatomy. ... The interatrial septum is the wall of tissue that separates the right and left atria of the heart. ... This page is about the muscular organ, the Heart. ... This page is about the muscular organ, the Heart. ...


Since the right side of the heart contains venous blood with a low oxygen content, and the left side of the heart contains arterial blood with a high oxygen content, it is beneficial to prevent any communication between the two sides of the heart and prevent the blood from the two sides of the heart from mixing with each other. In biology, a vein is a blood vessel which carries blood toward the heart. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... Section of an artery An arterial road is a class of highway. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ...


During development of the fetus, the inter-atrial septum develops to eventually separate the left and right atria. The foramen ovale remains open during fetal development to allow blood from the venous system to bypass the lungs and go to the systemic circulation. This is because prior to birth, the oxygenation of the blood is via the placenta and not the lungs. A layer of tissue begins to cover the foramen ovale during fetal development, and will close it completely soon after birth. After birth, the pressure in the pulmonary circulation drops, and the foramen ovale closes. In approximately 30% of adults the foramen ovale does not seal over. In this case, elevation of pressure in the pulmonary circulation (ie: pulmonary hypertension due to various causes, or transiently during a cough) can cause opening of the foramen ovale. This is known as a patent foramen ovale (PFO). Fetus at eight weeks Foetus redirects here. ... This page is about the muscular organ, the Heart. ... This page is about the muscular organ, the Heart. ... Two structures in the human body are called foramen ovale, meaning circular hole. ... The placenta is an ephemeral (temporary) organ present only in female placental mammals during gestation (pregnancy). ... The lungs flank the heart and great vessels in the chest cavity. ... In medicine, pulmonary hypertension (PH) is an increase in blood pressure in the pulmonary artery or lung vasculature. ...

Contents


Pathophysiology

In normal individuals, the chambers of the left side of the heart make up a higher pressure system than the chambers of the right side of the heart. This is because the left ventricle has to produce enough pressure to eject blood to the entire body, while the right ventricle has to produce enough pressure to eject blood to only the lungs. In the heart, a ventricle is a chamber which collects blood from an atrium (another heart chamber) and pumps it out of the heart. ... The right ventricle is one of four chambers (two atria and two ventricles) in the human heart. ... The lungs flank the heart and great vessels in the chest cavity. ...


In the event of an atrial septal defect, blood will flow from the left atrium to the right atrium. This is called a left-to-right shunt. This extra blood will cause a volume overload of both the right atrium and the right ventricle. This page is about the muscular organ, the Heart. ... This page is about the muscular organ, the Heart. ... A left-to-right shunt is a cardiac shunt which allows, or is designed to cause, blood to flow from the left heart to the right heart. ... This page is about the muscular organ, the Heart. ... The right ventricle is one of four chambers (two atria and two ventricles) in the human heart. ...


Any process that increases the pressure in the left ventricle can cause worsening of the left-to-right shunt. This includes hypertension, which increases the pressure that the left ventricle has to generate in order to open the aortic valve during ventricular systole, and coronary artery disease which increases the stiffness of the left ventricle, thereby increasing the filling pressure of the left ventricle during ventricular diastole. In the heart, a ventricle is a chamber which collects blood from an atrium (another heart chamber) and pumps it out of the heart. ... For other forms of hypertension see hypertension (disambiguation). ... The aortic valve is one of the valves of the heart. ... Systole can mean the following: Systole (medicine) is a term describing the contraction of the heart. ... Coronary heart disease (CHD), also called coronary artery disease (CAD) and atherosclerotic heart disease, is the end result of the accumulation of atheromatous plaques within the walls of the arteries that supply the myocardium (the muscle of the heart). ... Diastole is the period of time when the heart relaxes after contraction. ...


The right ventricle will have to push out more blood than the left ventricle due to the left-to-right shunt. This constant overload of the right side of the heart will cause an overload of the entire pulmonary vasculature. Eventually the pulmonary vasculature will develop pulmonary hypertension to try to divert the extra blood volume away from the lungs. In medicine, pulmonary hypertension (PH) is an increase in blood pressure in the pulmonary artery or lung vasculature. ...


The pulmonary hypertension will cause the right ventricle to face increased afterload in addition to the increased preload that the shunted blood from the left atrium to the right atrium caused. The right ventricle will be forced to generate higher pressures to try to overcome the pulmonary hypertension. This may lead to right ventricular failure (dilatation and decreased systolic function of the right ventricle) or elevations of the right sided pressures to levels greater than the left sided pressures. In cardiac physiology, afterload is the tension produced by a chamber of the heart in order to contract. ... In cardiac physiology, preload is the volume of blood present in a ventricle of the heart, after passive filling and atrial contraction. ... Systole can mean the following: Systole (medicine) is a term describing the contraction of the heart. ...


When the pressure in the right atrium rises to the level in the left atrium, there will no longer be a pressure gradient between these heart chambers, and the left-to-right shunt will diminish or cease.


If left uncorrected, the pressure in the right side of the heart will be greater than the left side of the heart. This will cause the pressure in the right atrium to be higher than the pressure in the left atrium. This will reverse the pressure gradient across the ASD, and the shunt will reverse; a right-to-left shunt will exist. This phenomenon is known as Eisenmenger's syndrome. Eisenmengers syndrome or Eisenmengers reaction is defined as the process in which a left-to-right shunt in the heart causes increased flow through the pulmonary vasculature, causing pulmonary hypertension, which in turn, causes increased pressures in the right side of the heart and reversal of the shunt...


Once right-to-left shunting occurs, a portion of the oxygen-poor blood will get shunted to the left side of the heart and ejected to the peripheral vascular system. This will cause signs of cyanosis. Cyanosis refers to the bluish coloration of the skin due to the presence of deoxygenated hemoglobin in blood vessels near the skin surface. ...


Epidemiology

As a group, atrial septal defects are detected in 1 child per 1500 live births. PFO are quite common (appearing in 10 - 20% of adults) but asymptomatic and therefore undiagnosed. ASDs make up 30 to 40% of all congenital heart disease that is seen in adults.1


The ostium secundum atrial septal defect accounts for 7% of all congenital heart lesions. This lesion shows a female preponderance, with a male : female ratio of 1:2.2


Types of atrial septal defects

Schemating drawing showing the location of different types of ASD, the view is into an opened right atrium. HV: right ventricle; VCS: superior caval vein; VCI: inferior caval vein; 1: upper sinus venosus defect; 2: lower sinus venosus defect; 3: secundum defect; 4: defect involving coronary sinus; 5; primum defect.
Schemating drawing showing the location of different types of ASD, the view is into an opened right atrium. HV: right ventricle; VCS: superior caval vein; VCI: inferior caval vein; 1: upper sinus venosus defect; 2: lower sinus venosus defect; 3: secundum defect; 4: defect involving coronary sinus; 5; primum defect.

There are many types of atrial septal defects. They are differentiated from each other by whether they involve other structures of the heart and how they are formed during the developmental process during early fetal development. Image File history File links ASD.png This is aschematic drawing of different types of the heart defect called ASD, atrial septal defect. ... Image File history File links ASD.png This is aschematic drawing of different types of the heart defect called ASD, atrial septal defect. ... Fetus at eight weeks Foetus redirects here. ...


Ostium secundum atrial septal defect

The ostium secundum atrial septal defect is the most common type of atrial septal defect, and comprises 6-10% of all congenital heart diseases.


The secundum atrial septal defect usually arises from an enlarged foramen ovale, inadequate growth of the septum secundum, or excessive absorption of the septum primum. 10 to 20 percent of individuals with ostium secundum ASDs also have mitral valve prolapse.3 Mitral valve prolapse (MVP) is a heart valve condition marked by the displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. ...


Natural history

Most individuals with an uncorrected secundum ASD don't have significant symptoms through early adulthood. About 70% develop symptoms by the time they are in their 40s. Symptoms are typically decreased exercise tolerance, easy fatigueability, palpitations, and syncope. A palpitation is an awareness of the beating of the heart, whether it is too slow, too fast, or at its normal frequency; brought on by overexertion, adrenaline, alcohol, disease or drugs, or as a symptom of panic disorder. ... Syncope may also refer to a linguistic phenomenon. ...


Complications of an uncorrected secundum ASD include pulmonary hypertension, right-sided heart failure, atrial fibrillation or flutter, stroke, and Eisenmenger's syndrome. In medicine, pulmonary hypertension (PH) is an increase in blood pressure in the pulmonary artery or lung vasculature. ... Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ... Atrial flutter is a rhythmic, fast rhythm that occurs in the atria of the heart. ... A stroke or cerebrovascular accident (CVA) occurs when the blood supply to a part of the brain is suddenly interrupted by occlusion (an ischemic stroke- approximately 90% of strokes), by hemorrhage (a hemorrhagic stroke - less than 10% of strokes) or other causes. ... Eisenmengers syndrome or Eisenmengers reaction is defined as the process in which a left-to-right shunt in the heart causes increased flow through the pulmonary vasculature, causing pulmonary hypertension, which in turn, causes increased pressures in the right side of the heart and reversal of the shunt...


While pulmonary hypertension is unusual before 20 years of age, it is seen in 50% of individuals above the age of 40. Progression to Eisenmenger's syndrome occurs in 5 to 10% of individuals late in the disease process. Eisenmengers syndrome or Eisenmengers reaction is defined as the process in which a left-to-right shunt in the heart causes increased flow through the pulmonary vasculature, causing pulmonary hypertension, which in turn, causes increased pressures in the right side of the heart and reversal of the shunt...


Patent foramen ovale

A patent foramen ovale (PAY-tent for-AYE-mun oh-VALL-ee) (PFO) is a small channel that has little hemodynamic consequence. Clinically it is linked to decompression sickness, paradoxical embolism and migraine. On echocardiography, there may not be any shunting of blood noted except when the patient coughs. In the fetal heart, the foramen ovale allows blood to enter the left atrium from the right atrium. ... Decompression sickness (DCS), divers disease, the bends, or caisson disease is the name given to a variety of symptoms suffered by a person exposed to a reduction in the pressure surrounding their body. ...


There is debate within the neurology and cardiology communities about the role of a PFO in cryptogenic neurologic events, i.e. strokes and transient ischemia attacks (TIAs) without any other potential cause. In addition, there is some data to suggest that PFOs may be involved in the pathogenesis of some migraine headaches. Several clinical trials are currently underway to investigate the role of PFO in these clinical situations.


Ostium primum atrial septal defect

The ostium primum atrial septal defect (also known as an endocardial cushion defect) is a defect in the atrial septum at the level of the tricuspid and mitral valves. This is sometimes known as an endocardial cushion defect because it often involves the endocardial cushion, which is the portion of the heart where the atrial septum meets the ventricular septum and the mitral valve meets the tricuspid valve. In anatomy, the heart valves are valves in the heart that prevent blood from flowing the wrong way. ... The mitral valve, also known as the bicuspid valve, is a valve in the heart that lies between the left atrium (LA) and the left ventricle (LV). ... The lumen of the atrial canal is reduced to a transverse slit, and two thickenings appear, one on its dorsal and another on its ventral wall. ...


Endocardial cushion defects are associated with abnormalities of the atrioventricular valves (the mitral valve and the tricuspid valve). These include the cleft mitral valve, and the single atrioventricular valve (a single large, deformed valve that flows into both the right ventricle and the left ventricle). The mitral valve, also known as the bicuspid valve, is a valve in the heart that lies between the left atrium (LA) and the left ventricle (LV). ... In anatomy, the heart valves are valves in the heart that prevent blood from flowing the wrong way. ...


Endocardial cushion defects are the most common congenital heart defect that is associated with Down's syndrome.


Sinus venosus atrial septal defect

A sinus venosus ASD is a type of atrial septum defect in which the defect in the septum involves the venous inflow of either the superior vena cava or the inferior vena cava. Superior vena cava - Wikipedia, the free encyclopedia /**/ @import /skins-1. ... This article may be too technical for most readers to understand. ...


A sinus venosus ASD that involves the superior vena cava makes up 2 to 3% of all intraatrial communications. It is located at the junction of the superior vena cava and the right atrium. It is frequently associated with anomalous drainage of the right-sided pulmonary veins into the right atrium (instead of the normal drainage of the pulmonary veins into the left atrium).4 The pulmonary veins carry oxygen rich blood from the lungs to the left atrium of the heart. ...

Ultrasound picture of the heart, seen in a subcostal view. The apex towards the right, atria to the left. ASD secundum seen as a discuntinuation of the white band of the atrial septum. Enlarged right atrium below, enlarged pulmonary veins seen entering left atrium above. (Echocardiogram: Wikipedia editor Kjetil Lenes (Ekko) )
Ultrasound picture of the heart, seen in a subcostal view. The apex towards the right, atria to the left. ASD secundum seen as a discuntinuation of the white band of the atrial septum. Enlarged right atrium below, enlarged pulmonary veins seen entering left atrium above. (Echocardiogram: Wikipedia editor Kjetil Lenes (Ekko) )

down sindrome child File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... down sindrome child File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... It has been suggested that Transesophageal_echocardiogram be merged into this article or section. ... A Wikipedia editor or Wikipedian is a person who has contributed changes to the articles of Wikipedia, the free online encyclopedia that anyone can edit. ...

Common or single atrium

is a failure of development of the embyologic components that contribute to the atrial septal complex. It is frequently associated with heterotaxy syndrome9.


Diagnosis

Diagnosis in children

Most individuals with a significant ASD are diagnosed in utero or in early childhood with the use of ultrasonography or auscultation of the heart sounds during physical examination. In Utero is the third and final studio album from the American grunge band, Nirvana. ... Medical ultrasonography is an ultrasound-based imaging diagnostic technique used to visualize internal organs, their size, structure and their pathological lesions. ... Auscultation is the technical term for listening to the internal sounds of the body, usually using a stethoscope. ... Front of thorax, showing surface relations of bones, lungs (purple), pleura (blue), and heart (red outline). ... In medicine, the physical examination or clinical examination is the process by which the physician investigates the body of a patient for signs of disease. ...


Diagnosis in adults

Many individuals with an ASD will have undergone surgical repair during childhood. The development of signs and symptoms due to an ASD are related to the size of the intracardiac shunt and the age of the individual. Individuals with a larger shunt tend to present with symptoms at a younger age.


Adults with an uncorrected ASD will present with symptoms of dyspnea on exertion (shortness of breath with minimal exercise), congestive heart failure, or cerebrovascular accident (stroke). They may be noted on routine testing to have an abnormal chest x-ray or an abnormal EKG and may have atrial fibrillation. Congestive heart failure (CHF), also called congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood throughout the body. ... A stroke or cerebrovascular accident (CVA) occurs when the blood supply to a part of the brain is suddenly interrupted by occlusion (an ischemic stroke- approximately 90% of strokes), by hemorrhage (a hemorrhagic stroke - less than 10% of strokes) or other causes. ... Frontal chest X-ray. ... ECG may also refer to the East Coast Greenway Lead II An Electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ... Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ...


Physical exam auscultation of the heart

The physical findings in adult with an ASD include those related directly to the intracardiac shunt, and those that are secondary to the right heart failure that may be present in these individuals. In medicine, the physical examination or clinical examination is the process by which the physician investigates the body of a patient for signs of disease. ... Auscultation is the technical term for listening to the internal sounds of the body, usually using a stethoscope. ... Congestive heart failure (CHF), also called congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood throughout the body. ...


Upon auscultation of the Heart sounds, there may be an ejection systolic murmur that is attributed to the pulmonic valve. This is due to the increased flow of blood through the pulmonic valve rather than any structural abnormality of the valve leaflets. Auscultation is the technical term for listening to the internal sounds of the body, usually using a stethoscope. ... Front of thorax, showing surface relations of bones, lungs (purple), pleura (blue), and heart (red outline). ...


In normal individuals, there is respiratory variations in the splitting of the second heart sound (S2). During respiratory inspiration, the negative intrathoracic pressure causes increased blood return into the right side of the heart. The increased blood volume in the right ventricle causes the pulmonic valve to stay open longer during ventricular systole. This causes a normal delay in the P2 component of S2. During expiration, the positive intrathoracic pressure causes decreased blood return to the right side of the heart. The reduced volume in the right ventricle allows the pulmonic valve to close earlier at the end of ventricular systole, causing P2 to occur earlier. Systole can mean the following: Systole (medicine) is a term describing the contraction of the heart. ...


In individuals with an ASD, there is a fixed splitting of S2. The reason why there is a fixed splitting of the second heart sound is that the extra blood return during inspiration gets equalized between the left and right atrium due to the communication that exists between the atria in individuals with ASD.


Echocardiography

On trans-thoracic echocardiography, an atrial septal defect may be seen on color flow imaging as a jet of blood from the left atrium to the right atrium. It has been suggested that Transesophageal_echocardiogram be merged into this article or section. ...


If agitated saline is injected into a peripheral vein during echocardiography, small air bubbles can be seen on echocardiographic imaging. It may be possible to see bubbles travel across an ASD either at rest or during a cough. (Bubbles will only flow from right atrium to left atrium if the RA pressure is greater than LA). In biology, a vein is a blood vessel which carries blood toward the heart. ...


Because better visualization of the atria is achieved on a trans-esophageal echocardiogram, this test may be performed in individuals with a suspected ASD which is not visualized on trans-thoracic imaging.


Newer techniques to visualize these defects involve intracardiac imaging with special catheters that are typically placed in the venous system and advanced to the level of the heart. This type of imaging is becoming more common and involves only mild sedation for the patient typically.


If the individual has adequate echocardiographic windows, it is possible to use the echocardiogram to measure the cardiac output of the left ventricle and the right ventricle independently. In this way, it is possible to estimate the shunt fraction using echocardiograpy.


Trans-Cranial Doppler (TCD)

A less invasive for finding PFO or other ASDs, than trans-esophagal ultrasound, is trans-cranial Doppler.


Electrocardiogram

The ECG findings in atrial septal defect vary with the type of defect the individual has. Individuals with atrial septal defects may have a prolonged PR interval (a first degree heart block). The prolongation of the PR interval is probably due to the enlargement of the atria that is common in ASDs and the increased distance due to the defect itself. Both of these can cause an increased distance of internodal conduction from the SA node to the AV node.5 ECG may also refer to the East Coast Greenway Lead II An Electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ... First degree heart block is a disease of the electrical conduction system of the heart. ... The sinoatrial node (abbreviated SA node, also called the sinus node) is the impulse generating (pacemaker) tissue located in the right atrium of the heart. ... The atrioventricular node (abbreviated AV node) is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles. ...


In addition to the PR prolongation, individuals with a primum ASD have a left axis deviation of the QRS complex while those with a secundum ASD have a right axis deviation of the QRS complex. Individuals with a sinus venosus ASD exhibit a left axis deviation of the P wave (not the QRS complex).


Treatment

Once an individual is found to have an atrial septal defect, a determination of whether it should be closed has to be made.


Surgical mortality due to closure of an ASD is lowest when the procedure is performed prior to the development of significant pulmonary hypertension. The lowest mortality rates are achieved in individuals with a pulmonary artery systolic pressure of less than 40 mmHg. One way of defining pressure is in terms of the height of a column of fluid that may be supported by that pressure; or the height of a column of fluid that exerts that pressure at its base. ...


If Eisenmenger's syndrome has occurred, there is significant risk of mortality regardless of the method of closure of the ASD. In individuals who have developed Eisenmenger's syndrome, the pressure in the right ventricle has raised high enough to reverse the shunt in the atria. If the ASD is then closed, the afterload that the right ventricle has to act against has suddenly increased. This may cause immediate right ventricular failure, since it may not be able to pump the blood against the pulmonary hypertension. Eisenmengers syndrome or Eisenmengers reaction is defined as the process in which a left-to-right shunt in the heart causes increased flow through the pulmonary vasculature, causing pulmonary hypertension, which in turn, causes increased pressures in the right side of the heart and reversal of the shunt... In cardiac physiology, afterload is the tension produced by a chamber of the heart in order to contract. ...


Closure of an ASD in individuals under age 25 has been shown to have a low risk of complications, and individuals have a normal lifespan (comparable to a healthy age-matched population). Closure of an ASD in individuals between the ages of 25 and 40 who are asymptomatic but have a significant shunt is controversial. Those that perform the procedure believe that they are preventing long-term deterioration in cardiac function and preventing progression of pulmonary hypertension.


If closure of an ASD is performed after age 40, there is improvement in symptoms compared to individuals who were treated medically. However, risk of cardiovascular problems were not decreased compared to the medically treated group.


Methods of closure of an ASD include surgical closure and percutaneous closure.


Evaluation prior to correction

Prior to correction of an ASD, an evaluation is made of the severity of the individual's pulmonary hypertension and whether it is reversible.


The evaluation may include a right heart catheterization. This involves placing a catheter in the venous system of the heart and measuring pressures and oxygen saturations in the SVC, IVC, right atrium, right ventricle, pulmonary artery, and in the wedge position. Individuals with a pulmonary vascular resistance (PVR) of less than 7 wood units show regression of symptoms (including NYHA functional class). On the other hand, individuals with a PVR of greater than 15 wood units have increased mortality associated with closure of the ASD. Superior vena cava - Wikipedia, the free encyclopedia /**/ @import /skins-1. ... This article may be too technical for most readers to understand. ... This page is about the muscular organ, the Heart. ... The right ventricle is one of four chambers (two atria and two ventricles) in the human heart. ... The pulmonary arteries carry blood from the heart to the lungs. ... The New York Heart Association (NYHA) Functional Classification provides a simple way of classifying the extent of heart failure. ...


If the pulmonary arterial pressure is more than 2/3 the systemic systolic pressure, there should be a net left-to-right shunt of at least 1.5:1 or evidence of reversibility of the shunt when given pulmonary artery vasodilators prior to surgery. (If eisenmenger's physiology has set in, it must be proven that the right-to-left shunt is reversible with pulmonary artery vasodilators prior to surgery.)


Surgical ASD closure

Surgical closure of an ASD involves opening up at least one atrium and closing the defect with a patch under direct visualization. In anatomy, the atrium (plural: atria) is the blood collection chamber of a heart. ...


Percutaneous ASD closure

Percutaneous closure of an ASD is currently only indicated for the closure of secundum ASDs with a sufficient rim of tissue around the septal defect so that the closure device does not impinge upon the SVC, IVC, or the tricuspid or mitral valves. Amplatzer Septal Occluder is commonly used to closed ASD. The ASO consists of two self-expandable round discs connected to each other with a 4-mm waist, made up of 0.004–0.005´´ nitinol wire mesh filled with Dacron fabric. Implantation of the device is relatively easy. The prevalence of residual defect is low. The disadvantages are a thick profile of the device and concern related to a large amount of nitinol (a nickel-titanium compound) in the device and consequent potential for nickel toxicity. Superior vena cava - Wikipedia, the free encyclopedia /**/ @import /skins-1. ... This article may be too technical for most readers to understand. ... In anatomy, the heart valves are valves in the heart that prevent blood from flowing the wrong way. ... The mitral valve, also known as the bicuspid valve, is a valve in the heart that lies between the left atrium (LA) and the left ventricle (LV). ...


Percutaneous closure is the method of choice in most centres.10


Associated conditions

Due to the communication between the atria that occurs with ASDs, a number of disease entities are possible.


Decompression sickness

ASDs, and particularly PFOs, are a predisposing risk factor for decompression sickness in divers because a proportion of venous blood carrying inert gases, such as helium or nitrogen does not pass through the lungs.6,7 The only way to release the excess inert gases from the body is to pass the blood carrying the inert gases through the lungs to be exhaled. If some of the inert gas-laden blood passes through the PFO, it avoids the lungs and the inert gas is more likely to form large bubbles in the arterial blood stream causing decompression sickness. Decompression sickness (DCS), divers disease, the bends, or caisson disease is the name given to a variety of symptoms suffered by a person exposed to a reduction in the pressure surrounding their body. ... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... The lungs flank the heart and great vessels in the chest cavity. ...


Paradoxical emboli

Venous thrombi (clots in the veins) are quite common. Embolization (dislogdement of thrombi) normally go to the lung and cause pulmonary emboli. In an individual with ASD, these emboli can potentially enter the arterial system. This can cause any phenomenon that is attributed to acute loss of blood to a portion of the body, including cerebrovascular accident (stroke), infarction of the spleen or intestines, or even a distal extremity (ie: finger or toe). A thrombus or blood clot is the final product of blood coagulation, through the aggregation of platelets and the activation of the humoral coagulation system. ... In biology, a vein is a blood vessel which carries blood toward the heart. ... A pulmonary embolism (thromboembolism) occurs when a blood clot, generally a venous thrombus, becomes dislodged from its site of formation and embolizes to the arterial blood supply of one of the lungs. ... A stroke or cerebrovascular accident (CVA) occurs when the blood supply to a part of the brain is suddenly interrupted by occlusion (an ischemic stroke- approximately 90% of strokes), by hemorrhage (a hemorrhagic stroke - less than 10% of strokes) or other causes. ... The spleen is a ductless, vertebrate gland that is not necessary for life but is closely associated with the circulatory system, where it functions in the destruction of old red blood cells in holding a reservoir of blood. ... The intestine is the portion of the alimentary canal extending from the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine. ...


This is known as a paradoxical embolus because the clot material paradoxially enters the arterial system instead of going to the lungs.


Migraine

Some recent research has suggested that a proportion of cases of migraine may be caused by patent foramen ovale. While the exact mechanism remains unclear, closure of a PFO can reduce symptoms in certain cases8.


External links

  • Atrial Septal Defect information from Seattle Children's Hospital Heart Center
  • Patent Foramen Ovale from HealthONE Denver ONE Magazine

References

1. Kaplan S. Congenital heart disease in adolescents and adults. Natural and postoperative history across age groups. Cardiol Clin. 1993 Nov;11(4):543-56. (Medline abstract)


2. Feldt RH, Avasthey P, Yoshimasu F, Kurland LT, Titus JL. Incidence of congenital heart disease in children born to residents of Olmsted County, Minnesota, 1950-1969. Mayo Clin Proc. 1971 Dec;46(12):794-9. (Medline abstract)


3. Leachman RD, Cokkinos DV, Cooley DA. Association of ostium secundum atrial septal defects with mitral valve prolapse. Am J Cardiol. 1976 Aug;38(2):167-9. (Medline abstract)


4. Davia JE, Cheitlin MD, Bedynek JL. Sinus venosus atrial septal defect: analysis of fifty cases. Am Heart J. 1973 Feb;85(2):177-85. (Medline abstract)


5. Clark EB, Kugler JD. Preoperative secundum atrial septal defect with coexisting sinus node and atrioventricular node dysfunction. Circulation. 1982 May;65(5):976-80. (Medline abstract)


6. Lier H, Schroeder S, Hering R. Patent foramen ovale: an underrated risk for divers? Dtsch Med Wochenschr. 2004 Jan 2;129(1-2):27-30. (Medline abstract)


7. Saary MJ, Gray GW. A review of the relationship between patent foramen ovale and type II decompression sickness. Aviat Space Environ Med. 2001 Dec;72(12):1113-20. (Medline abstract)


8. Adams HP. Patent foramen ovale: paroxical embolism and paradoxical data. Mayo Clin Proc 2004;79:15-20.


9. Valdes-Cruz LM, cayre RO. Echocardiographic diagnosis of congenital heart disease. Philadelphia, 1998.


10. Bjornstad PG. Is interventional closure the current treatment of choice for selected patients with deficient atrial septation? Cardiology in the Young. 2006;16:3-10.


See also


  Results from FactBites:
 
Atrial septal defect - Wikipedia, the free encyclopedia (2907 words)
Atrial septal defects [ASD] are a group of congenital heart diseases that enables communication between atria of the heart and may involve the interatrial septum.
Endocardial cushion defects are associated with abnormalities of the atrioventricular valves (the mitral valve and the tricuspid valve).
A sinus venosus ASD is a type of atrial septum defect in which the defect in the septum involves the venous inflow of either the superior vena cava or the inferior vena cava.
  More results at FactBites »

 
 

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