heart author" faq
 
     
Atrial Septal Defect
      

This condition accounts for a third of the adult cases of congenital heart disease, occurring two to three times more frequent in women.

It may occur in various positions in the atrial septum (see figure 20):

1) lower part, ostium primum, 15% of cases;

2) ostium secundum, in area of fossa ovalis (prior site of foramen avalis in the fetus, allowing both left and right atrium to communicate), 75%;

3) upper atrial septum, sinus (site of sinus or pocket where inferior vena cava (IVC) and superior vena cava (SVC) empty into right atrium) venosus, 10%.

Most cases are due to spontaneous genetic mutations, but others are inherited.

The results of these defects come from the shunting of blood from one atrium to the other.

The direction and size of the shunting are determined by the size of the defect and compliance of the ventricles.

A small defect less than 0.5 cm in diameter is associated with a small shunt and no significant sequelae.

But a larger defect, more than 2 cm in diameter may be associated with a large shunt with important blood flow changes.

In most cases with atrial defects, the right ventricle is more flexible than the left; thus, the left atrial oxygenated blood is shunted to the right atrium causing increased blood flow and enlargement of the atria, right ventricle, and pulmonary arteries (see figure 112a ).

 

But if the right ventricle fails, the shunt may reverse and go right to left.

Diagnosis includes the following:


1) Auscultation of the heart sounds and searching for heart murmurs


2) EKG


3) Echocardiography including transesophageal, and doppler ( Figure 112b )


4) Heart catherterization to determine size and direction of shunt and whether there is high blood pressure in the pulmonary arteries.

Patients with moderate or even large atrial septal defects often have no symptoms until 30 to 40 years of age.

Ultimately, with the increased blood flow through the right heart chambers, right ventricular enlargement and failure occurs.

Symptoms include fatigue and shortness of breath on exertion.

Also, supraventricular arrhythmia like atrial tachycardia (see figure 1) and fibrillation (see figure 14), heart failure, and embolism through the defect may occur and can result in death.

An example of a complication of a paradoxical embolism in a case of a patent foramen ovale is illustrated below(New England Journal of Medicine 2007;357(22):2285):

Supplement to: Dörr M and Hummel A. Paradoxical Embolism — Thrombus in a Patent Foramen Ovale. N Engl J Med 2007;357(22):2285.

An 85-year-old woman was admitted with progressive dyspnea and chest pain that had started suddenly 2 days earlier. Physical examination revealed formerly undiagnosed atrial fibrillation with a normal heart rate and normal blood pressure. Examination of the lungs did not show any pathological findings. Pulmonary embolism was diagnosed on spiral computed tomography (Panel A, sagittal reconstruction), which showed intraluminal filling defects (arrows) and total occlusions of the upper and lower segmental arteries by clots (arrowheads). Duplex ultrasonography revealed an underlying deep-vein thrombosis of the right superficial femoral vein. Transthoracic echocardiography showed typical signs of moderate right heart strain. Anticoagulation therapy with low-molecular-weight heparin was started. One week later, repeated transthoracic echocardiography showed a fluttering thrombus within the right atrium (Panel B, arrow). Two-dimensional transesophageal echocardiography revealed a vermicular thrombus trapped in the patent foramen ovale with floating parts in the right and left atrium (Panel C, arrow, and video clip, available with the full text of this article at www.nejm.org). Emergency cardiac surgery was performed in which a thrombus of approximately 8 cm in length was extracted and the foramen ovale was closed. Surprisingly, the left atrial fraction of the thrombus had already disappeared without clinical signs of arterial embolism. The patient was discharged in good clinical condition 2 weeks later while receiving anticoagulant therapy for persistent atrial fibrillation. Ten months later, she was still doing well without relapse.

 

see video

This video is copyright protected, not downloadable and can be found in the New England Journal of Medicine, issue November 29, 2007, page , volume , in the article called Paradoxical Embolism. It is shown here to point out the embolus's fragile, serpigenous, loosely structured, thin , floating, mobile state(altered by the periodic contractions of the heart) caught in the hole (Foramen Ovale) connecting the two atria.

 

 

Treatment

If the blood flow through the pulmonary artery is 1.5 times larger than the flow out of the left ventricle, surgical closure of the defect is recommended.

But surgery is not recommended for patients with irreversible pulmonary arterial disease and high pulmonary blood pressure.

Defects of the secundum type of atrial septal defect usually go undetected in the first year or two of life because of the lack of symptoms and unimpressive auscultatory findings. A soft systolic murmur is the usual reason for referral. Symptoms become more common in persons in their late teens and twenties, and by age 40 the majority of these individuals are symptomatic, some severely so.
Spontaneous closure of these defects is rare beyond the first two years of life. Transcatheter closure of centrally located secundum in selected older infants, children and adults using a double umbrella or a buttoned device appears to be an acceptable alternative to surgical closure(i.e.the Amplatzer septal occluder).

THE AMPLATZER SEPTAL OCCLUDER

http://www.amplatzer.com/images/asdsmall.jpg

Device Description

The Amplatzer septal occluder is a self-expandable, double disc device made from a Nitinol wire mesh. The two discs are linked together by a short connecting waist corresponding to the size of the ASD. In order to increase its closing ability, the discs and the waist are filled with polyester fabric. The polyester fabric is securely sewn to each disc by a polyester thread.

asdsmall Fig.1

clamshell device atrial septal defect Fig.1a

The Amplatzer delivery system was designed specifically to facilitate attachment, loading, delivery and deployment of the Amplatzer septal occluder and is comprised of a delivery sheath, dilator, loading device, plastic vise and delivery cable.

TRANSCATHETER CLOSURE OF ATRIAL SEPTAL DEFECT

Isolated atrial septal defect accounts for approximately 6% of CHD. The pathophysiology is that of a low-pressure left-to-right shunt with right heart dilation and pulmonary overcirculation. Symptoms are rare before the third decade and include CHF, pulmonary hypertension and atrial arrhythmia. Rarely a very large defect may cause CHF with growth failure in a young child. It is difficult to predict which patients will go on to develop symptoms. Not all symptoms are reversible if the defect is repaired in adulthood. For these reasons, moderate to large defects found in young children are usually closed before the child starts school or as soon as they are found in older children.

Surgical closure performed since 1948 enjoys excellent results and very low morbidity and mortality. A sternal or more uncommonly thoracic incision is required as is cardio-pulmonary bypass and a three-day to a one-week hospitalization.

King et al. reported the first transcatheter closure of an ASD in 1976 using a device that required an extremely large sheath (or catheter) for implantation. Since then, several different designs have undergone and continue to undergo clinical testing with generally good results. As of this writing, there are several active clinical trials in the United States and abroad using devices such as the Amplatzer, the CardioSeal, and the Angel Wings. Although varying in specific details of construction, most devices have in common two discs connected together in the center and designed so that they can collapse to fit inside a catheter and expand again when positioned in the heart.

In the typical "clamshell" design, two large discs positioned on either side of the defect are responsible for closure of the defect. Potential disadvantages of this design include the need for large discs relative to the size of the defect and—because of the lack of a centering mechanism—the technical difficulty in getting the device to sit properly within the defect. The Amplatzer ASD occluder is an example of the "self-centering design" where the connection between the two discs is larger in diameter and serves to center the device within the defect and also aids in occlusion (asdwax-Fig1b.jpg).

asdwax-Fig1b.jpg

Implantation of the Amplatzer ASD occluder. From A to E: The delivery catheter is positioned across the atrial defect; the left atrial disc with the self-centering connecting stalk is delivered; the device is withdrawn so that the connecting stalk is within the ASD and the left disc is firm against the atrial septum; the right atrial disc is delivered, and the delivery cable is disconnected from the device. Until the delivery cable is disconnected, the device can be withdrawn back into the catheter and removed from the body.

The Amplatzer has been used in over 2,700 patients world wide since 1995 .The Amplatzer offers several advantages over competing designs. Because of its Nitinol (memory wire) construction and unique design it can be withdrawn back into the catheter and removed from the body if proper positioning in the heart is not possible. The device is available in a range of sizes from 4 mm to 32 mm; the appropriate size allows the connecting stalk to fill the ASD, center the device, ensure complete closure and allow the atrial discs to be relatively smaller than those of competing designs.

asdwax-Fig1b.jpg above demonstrates the technique for inserting the Amplatzer. The procedure is currently performed under general anesthesia to allow for transesophageal echo during the procedure. The patient is observed overnight and discharged the next morning. Patients take a baby aspirin daily for six months until endothelialization of the device is complete. Follow-up consists of an echocardiogram and a chest x-ray at six months and one year. Possible complications include infection at the catheter site, arrhythmia, stroke, cardiac perforation, device embolization and incomplete closure.

Most, but not all, secundum atrial septal defects are amenable to closure by the Amplatzer device. Currently criteria include a defect size of less than or equal to 32 mm and a 4 mm rim of atrial septal tissue surrounding the defect. These anatomical details can usually be ascertained by a careful transthoracic echocardiogram. Occasionally, in larger patients a transesphogeal echo is needed to properly visualize the defect. If this is required, we offer patients the option of having the TEE under general anesthesia with catheter closure of the defect to follow if appropriate.

At the last reporting of U.S. results, 186 patients had atrial defects closed with the Amplatzer device with no major complications. There were 8 (4.3%) minor complications including 4 device embolizations (2 removed percutaneously and 2 removed surgically) and 4 instances of arrhythmia (3 transient, 1 persistent complete heart block). The closure rate for the 121 patients with 6 months follow-up was 99%.

Therapeutic cardiac catheterization in children :DAVID F. WAX, MD;Fall 1999

http://www.childsdoc.org/Fall99/catheterization.asp

Sandwich cookie figure1c analogy of Amplatzer device:The two cookies form the two slices of the sandwich and the atrial septal defect the creme .


The risk of surgery are minimal (>than 0.5%) with all these children home by the fourth postoperative day. Morbidity in adults and the low risk of surgical closure in young children mandate surgery in the preschool or preadolescent years.
Although life-threatening complications after closure of ASDs are rare, transient postoperative atrial arrhythmias and postpericardiotomy syndrome with pericardial effusions occasionally seen. The long term prognosis for a normal life expectancy and functional capability is excellent for patients who have closure of an uncomplicated ASD during the first two decades of life.

MEDICAL MANAGEMENT
The few infants who present with symptoms of congestive failure are treated with digoxin and, if necessary, diuretics and are studied by cardiac catheterization. If the defect is uncomplicated and the symptoms persist despite a trial of therapy, surgical closure is advised without further delay. For asymptomatic infants and children, closure is recommended just before entry into school. Restrictions of activity or exercise are unnecessary. If the physical, laboratory, and echocardiographic findings are completely characteristic, preoperative catheterization is not necessary. Closure is recommended if the defect is large and if there is right ventricular volume overload or (ecbocardiography. In those with puImonary hypertension closure is recommended for patients with Qy/Q, ratios >1.5:1 by catheterization provided that the systemic arterial saturation is >92 percent and total Rf < 15 Wood units. Closure would seem prudent before pregnancy or the use of contraceptives in view of the tendency to develop rapidly progressive PVOD in this setting.

Transcatheter closure of centrally located secundum in selected older infants, children, and adults using a double-umbrella ("clamshell") or a buttoned device appears to be an acceptable alternative to surgical closure(see above).. Infective endocarditis is rare, and antibiotic coverage at times of possible bacteremia is recommended only if associated mitral value disease is suspected.

Below is a summary of a recent article appearing in the JACC,17 January 03 issue describing the safe use of intracardiac echocardiography to guide the placement of the Amplatzer septal occluder over atrial septal defects successfully without general anesthesia ,which is required with transesophageal echocardioigraphy ,allowing the patient to be discharged the same day as the procedure.

INTRACARDIAC ECHOCARDIOGRAPHIC-GUIDED DEVICE CLOSURE OF ATRIAL SEPTAL DEFECTS

Michael J. Mullen, MD, MRCP,* Bryan F. Dias, MD,* Fiona Walker, MD, MRCP,*
Samuel C. Siu, MD, SM,* Lee N. Benson, MD, FACC,t Peter R. McLaughlin, MD, FACC*
Toronto, Canada
OBJECTIVES This study was designed to determine the feasibility and accuracy of intracardiac echocardiography, (ICE) in guiding percutaneous closure of atrial septal defects (ASD).
BACKGROUND Intracardiac echocardiography is a novel imaging technique that might be used to guide interventional procedures. The sensitivity and specificity of ICE, compared to standard imaging techniques, in detecting potentially adverse procedural events and guiding remedial action will be an important consideration in its use.
METHODS In a prospective study, 24 patients underwent device closure of ASD using ICE as the primary echocardiographic imaging modality. Feasibility was expressed as proportion of cases in which complete diagnostic ICE imaging was achieved. Accuracy was expressed as the percent agreement between ICE and simultaneously performed transesophageal echocardiography (TEE).
RESULTS Hligh-quality ICE images were acquired in all patients, though images were limited in two patients with aneurvsmal septa(See figures below). Intracardiac echocardiography successfully guided closure of 24 out of 25 ASDs (96%) in 23 patients. There was close agreement between ICE and TEE in their assessment of device position and the adequacy of septal capture before device release (98%) and in identifying the presence of significant residual shunts. Intracardiac echocardiography detected all potentially adverse events, including four malpositions, and guided appropriate remedial action.
CONCLUSIONS Intracardiac echocardiography guided device closure of secundum ASDs is feasible in the majority of patients and provides diagnostic data comparable to TEE. These data indicate that ICE may be used to guide routine closure of ASDs in adults without the need for TEE and general anesthesia. JAm Coll Cardiol 2003;41:285-92) © 2003 by the American College of Cardiology Foundation

asdICE-Fig16.jpg: Fluoroscopic position of the intracardiac transducer with corresponding echocardiographic images. (A) Long-axis view of the tricuspid valve (TV), right ventricle (RV), and right ventricular outflow tract viewed from the right atrium (RA). (B) Rotation of the catheter clockwise reveals a long-axis view of atrial septum and the left atrium (LA); color Doppler demonstrates an atrial septal defect. (C) Advancing the transducer cranially with slight posterior flexion reveals the sinus venosus septum, superior vena cava (SVC), and origin of the right upper pulmonary vein (RUPV). (D) Further posterior flexion and rotation of the transducer towards the TV provides a short axis image of the aorta (Ao), atrial septum, and atrial septal defect.

asdICE-Fig17.jpg (A) Amplatzer septal occluder with both left atrial (LA) and right atrial (RA) discs visible during deployment. (B) Short-axis view of Amplatzcr device following deployment. (C and D) Long-axis views illustrating capture of the membranous inferior and muscular superior septum.

asdICE-Fig18.jpg. Adverse procedural events detected by intracardiac echocardiography. (A and B) Malpositioned Cardioscal and Amplatzer devices with both discs on right atrial (RA) side of aorta (Ao). (C) Color flow demonstrates a residual leak in this patient, with two devices already deployed. Intracardiac echocardiography demonstrated this to be a small additional fenestration. (D) This second large inferior defect was not identified bytransesophageal echocardiograhy.Note the sizing ballon inflated within a more superior defect and the coronary sinus(CS) and mitral valve(MV).

 

 


ATRIAL ANEURYSM.

A bulging or ballooning out of part of the wall of one of the heart's upper chambers (atria ). If the aneurysm is present in the wall between the atria (the atrial septum), it is also known as an atrial septal aneurysm (ASA), an aneurysm of septum primum or an aneurysm of the septum secundum.

An ASA has been associated with an increased risk of stroke and is often accompanied by the presence of a patent foramen ovale (PFO), an opening between the upper chambers (atria) of the heart. Normally, this opening is present in the developing fetus, and closes shortly after birth. It is often present since birth (congenital).

 

Atrial Septal Aneurysm

Banu Mahalingam, M.D.,Echocardiography Journal:http://www2.umdnj.edu/%7Eshindler/ias2la.gif

Atrial Septal Aneurysm: case presentation at the Froedtert Hospital Grand Rounds web site.

Echocardiographic Classifications of Atrial Septal Aneurysm Motion

J Am Soc Echocardiogr 1997;10:644-56.

asaFig.22a-fig6.jpg :Atrial septal aneurysm protrudes from the midline of the atrial septum to the left atrium .

Type 1R: The ASA protrudes from the midline of the atria to the right atrium throughout the cardiorespiratory cycle.
Type 2L: The ASA protrudes from the midline of the atrial septum to the left atrium throughout the cardiorespiratory cycle.
Type 3RL: The maximal excursion of the ASA is toward the right atrium with a lesser excursion toward the left atrium.
Type 4LR: The maximal excursion of the ASA is toward the left atrium with a lesser excursion toward the right atrium.
Type 5: The ASA movement is bidirectional and equidistant to the right as well as to the left atrium during the cardiorespiratory cycle.

Am J Cardiol 1985;56:653-67.

Type 1: The ASA projects into the right atrium during diastole, with early systolic bulging into the left atrium, followed by a rightward crossing-over motion in mid-systole and during inspiration or expiration.
Type 2: Sustained rightward deviation during expiration and a leftward motion only during inspiration in early ventricular systole.
Type 3: The ASA remains in the right atrium, with an undulating motion during all phases of the cardiorespiratory cycle.

J Am Coll Cardiol 1985;6:1370-82.

Type 1A: The bulging in the right atrium is motionless.
Type 1B: The bulging is confined to the right atrium but with rapid phasic oscillation during inspiration.
Type 2: The ASA protrudes maximally into the left atrium and is accompanied by excursion into the right atrium.

Association with Cerebrovascular Events:

Low incidence of embolic strokes with atrial septal aneurysms: A prospective, long-term study
Burger AJ; Sherman HB; Charlamb MJ
Am Heart J 2000 Jan;139(1 Pt 1):149-52


Abstract


BACKGROUND:

Previous retrospective studies have suggested that atrial septal aneurysms (ASA) are associated with embolic strokes. The purpose of this study was to evaluate prospectively the embolic potential of ASA. METHODS: Of 846 consecutive patients undergoing cardiac surgery from December 1990 to March 1993, we identified 42 patients who had ASA as an incidental finding on intraoperative transesophageal echocardiography. Patency was determined by color and/or contrast echocardiography. The majority of patients were given aspirin postoperatively. Patients were monitored by personal and/or telephone interviews, and their clinical conditions were confirmed by their personal physicians. Any patient with any question of a neurologic event had a detailed neurologic history, examination, and computed tomographic or magnetic resonance imaging scan. RESULTS: The incidence of ASA in our population was 4.9%; there were 22 men and 20 women with a mean age of 72 years. Oscillating ASA were present in 28 patients and fixed aneurysm in 10. The mean diameter of the ASA was 21 +/- 4 mm. Eighteen (56%) of 32 patients had a patent ASA. Patients were monitored for a mean period of 69.5 months (56 to 85 months). No patient had a cerebrovascular event or systemic embolization.

CONCLUSION:

The risk of cerebrovascular events or embolic strokes in our patient population with incidental ASA was low. If treatment is needed for this condition, aspirin appears to be effective therapy.

 

Mugge A. Daniel WG. Angermann C. Spes C. Khandheria BK. Kronzon I. Freedberg RS. Keren A. Denning K. Engberding R. et al.


Atrial septal aneurysm in adult patients. A multicenter study using transthoracic and transesophageal echocardiography
Circulation. 91(11):2785-92, 1995 Jun 1.


Abstract


BACKGROUND:

An atrial septal aneurysm (ASA) is a well-recognized abnormality of uncertain clinical relevance. We reevaluated the clinical significance of ASA in a large series of patients. The aims of the study were to define morphological characteristics of ASA by transesophageal echocardiography (TEE), to define the incidence of ASA-associated abnormalities, and to investigate whether certain morphological characteristics of ASA are different in patients with and without previous events compatible with cardiogenic embolism.

METHODS AND RESULTS:

Patients with ASA were enrolled from 11 centers between May 1989 and October 1993. All patients had to undergo transthoracic and transesophageal echocardiography within 24 hours of each other; ASA was defined as a protrusion of the aneurysm > 10 mm beyond the plane of the atrial septum as measured by TEE. Patients with mitral stenosis or prosthesis or after cardiothoracic surgery involving the atrial septum were excluded. Based on these criteria, 195 patients 54.6 +/- 16.0 years old (mean +/- SD) were included in this study. Whereas TEE could visualize the region of the atrial septum and therefore diagnose ASA in all patients, ASA defined by TEE was missed by transthoracic echocardiography in 92 patients (47%). As judged from TEE, ASA involved the entire septum in 100 patients (51%) and was limited to the fossa ovalis in 95 (49%). ASA was an isolated structural defect in 62 patients (32%). In 106 patients (54%), ASA was associated with interatrial shunting (atrial septal defect, n = 38; patent foramen ovale, n = 65; sinus venosus defect, n = 3). In only 2 patients (1%), thrombi attached to the region of the ASA were noted. Prior clinical events compatible with cardiogenic embolism were associated with 87 patients (44%) with ASA; in 21 patients (24%) with prior presumed cardiogenic embolism, no other potential cardiac sources of embolism were present. Length of ASA, extent of bulging, and incidence of spontaneous oscillations were similar in patients with and without previous cardiogenic embolism; however, associated abnormalities such as atrial shunts were significantly more frequent in patients with possible embolism.

CONCLUSIONS:

As shown previously, TEE is superior to the transthoracic approach in the diagnosis of ASA. The most common abnormalities associated with ASA are interatrial shunts, in particular patent foramen ovale. In this retrospective study, patients with ASA (especially with shunts) showed a high frequency of previous clinical events compatible with cardiogenic embolism; in a significant subgroup of patients, ASA appears to be the only source of embolism, as judged by TEE. Our data are consistent with the view that ASA is a risk factor for cardiogenic embolism, but thrombi attached to ASA as detected by TEE are apparently rare.

 

Cabanes L. Mas JL. Cohen A. Amarenco P. Cabanes PA. Oubary P. Chedru F. Guerin F. Bousser MG. de Recondo J.
Atrial septal aneurysm and patent foramen ovale as risk factors for cryptogenic stroke in patients less than 55 years of age. A study using transesophageal echocardiography.
Stroke. 24(12):1865-73, 1993 Dec.


Abstract


BACKGROUND AND PURPOSE:

An association between atrial septal aneurysm and embolic events has been suggested. Atrial septal aneurysm has been shown to be associated with patent foramen ovale and, in some reports, with mitral valve prolapse. These two latter cardiac disorders have been identified as potential risk factors for ischemic stroke. The aim of this prospective study was to assess the role of atrial septal aneurysm as an independent risk factor for stroke, especially for cryptogenic stroke.

METHODS:

We studied the prevalence of atrial septal aneurysm, patent foramen ovale, and mitral valve prolapse in 100 consecutive patients < 55 years of age with ischemic stroke who underwent extensive etiological investigations. We compared these results with those in a control group of 50 consecutive patients. The diagnosis of atrial septal aneurysm and patent foramen ovale relied on transesophageal echocardiography with a contrast study and that of mitral valve prolapse, on two-dimensional transthoracic echocardiography. RESULTS: Stepwise logistic regression analysis showed that atrial septal aneurysm (odds ratio, 4.3; 95% confidence interval, 1.3 to 14.6; P = .01) and patent foramen ovale (odds ratio, 3.9; 95% confidence interval, 1.5 to 10; P = .003) but not mitral valve prolapse were significantly associated with the diagnosis of cryptogenic stroke. The stroke odds of a patient with both atrial septal aneurysm and patent foramen ovale were 33.3 times (95% confidence interval, 4.1 to 270) the stroke odds of a patient with neither of these cardiac disorders. For a patient with atrial septal aneurysm of > 10-mm excursion, the stroke odds were approximately 8 times the stroke odds of a patient with atrial septal aneurysm of < 10 mm.

CONCLUSIONS:

This study shows that atrial septal aneurysm and patent foramen ovale are both significantly associated with cryptogenic stroke and that their association has a marked synergistic effect. Atrial septal aneurysms of > 10-mm excursion are associated with a higher risk of stroke.

 

Pearson AC. Nagelhout D. Castello R. Gomez CR. Labovitz AJ.
Atrial septal aneurysm and stroke: a transesophageal echocardiographic study.
Journal of the American College of Cardiology. 18(5):1223-9, 1991 Nov 1.


Abstract


The prevalence and morphologic characteristics of atrial septal aneurysms identified by transesophageal echocardiography in 410 consecutive patients are described. Two groups of patients were compared: Group I consisted of 133 patients referred for evaluation of the potential source of an embolus and Group II consisted of 277 patients referred for other reasons. An atrial septal aneurysm was diagnosed by transesophageal echocardiography in 32 (8%) of the 410 patients. Surface echocardiography identified only 12 of these aneurysms. Atrial septal aneurysm was significantly more common in patients with stroke (20 [15%] of 133 vs. 12 [4%] of 277) (p less than 0.05); right to left shunting at the atrial level was demonstrated in 70% of patients in Group I and 75% of patients in Group II by saline contrast echocardiography. Four patients in Group I had an atrial septal defect with additional left to right flow. There was no difference between the two groups in aneurysm base width, total excursion or left atrial or right atrial excursion. However, Group I patients had a thinner atrial septal aneurysm than did Group II patients.

It is concluded that an atrial septal aneurysm occurs commonly in patients with unexplained stroke, is more frequently detected by transesophageal echocardiography than by surface echocardiography and is usually associated with right to left atrial shunting.

Treatment (anticoagulant therapy vs. surgery) of atrial septal aneurysm identified in stroke patients can be determined only by long-term follow-up studies.

 

Belkin RN., Hurwitz BJ., Kisslo J.
Atrial septal aneurysm: association with cerebrovascular and peripheral embolic events.
Stroke. 18(5):856-62, 1987 Sep-Oct.


Abstract


Patient records in 36 consecutively identified patients with typical echocardiographic findings of atrial septal aneurysm were reviewed. Ten of the 36 (28%) had cerebrovascular events. Of these 10, 5 had completed strokes of definite embolic origin on the basis of clinical, angiographic, and computed tomographic findings; 2 had transient ischemic attacks of probable embolic origin. One of the 36 patients had a definite peripheral vascular embolus. Thus, 6 of 36 consecutively identified patients with atrial septal aneurysm (17%) had definite embolic events and 8 of 36 (22%) had definite or possible embolic events.

The cause of the association between atrial septal aneurysm and emboli is unknown. While aneurysm-associated thrombus has been suggested, the high proportion (90%) of patients with interatrial shunting demonstrated by contrast echocardiography in this study suggests paradoxical embolization as a potential cause. Whatever its mechanism, the high prevalence of embolic events in this series strongly supports the premise that atrial septal aneurysm is a cardiac abnormality with embolic potential.

 

JANUARY 2002: Contents
Clin. Cardiol. 25,42 (2002)
Images in Cardiology
This section edited by Edward A. Geiser, M.D.


A Jumping Rope Giant Atrial Septal Aneurysm and Territorial Disputes
Ara Sadaniantz, M.D., FACC, FESC
The Miriam Hospital, Brown University School of Medicine, Providence, Rhode Island. USA

asaFIG22b-fig7.jpg:In the short-axis view a spherical cystic-appearing mass (arrows) measures 2 cm in diameter. Arrows = septum secundum, RA = right atrium.

 

 

 

asaFIG22c-fig8.Base of ostium secundum measured 1.2cm.The menbrane had the appearance of a jumping rope,protruding 3.7cm into the right atrium with phasic excursion, but it did not enter the left atrium(LA).

 

 

asaFIG22d-fig.9.jpg: Agitated saline contrast injection into an antecubital vein opacifies the right atrium without any evidence of left to right shunting. Abbreviations as in asa figures 7and 8.


Interatrial shunt is the most common abnormality associated with atrial septal aneurysm (ASA) and its detection is more common with transesophageal echocardiogram. The definition of ASA includes protrusion of atrial septum 15 mm or greater beyond the plane of interatrial septum with phasic excursion during cardiorespiratory cycle.


An 81-year-old woman was referred for transesophageal echocardiogram to further evaluate a possible mass in the right atrium that appeared to be suspicious on transthoracic. echocardiogram. She was sedated with 1 mg Versed® and 25 mg Demerol(R) IV and her oropharynx was anesthetized with xylocaine spray. The probe was introduced without difficulty into the esophagus. In the short-axis view a spherical cystic-appearing mass measuring 2 cm in diameter was identified (asaFig22b-fig.7.jpg). In the long-axis view visualizing the atrial septum, an extensively redundant septum secundum membrane was identified overlaying the ostium secundum. The base of ostium secundum measured 1.2 cm (asaFig22c-fig:8). The membrane, when seen in real time, had the appearance of a jumping rope. It protruded 3.7 cm into the right atrium with phasic excursion but it did not enter the left atrium. An agitated saline solution that filled the right atrium without any evidence of left to right shunting was used as contrast agent. The negative contrast in the right atrium, beyond the ostium secundum, is functionally within the territory of the left atrium due to the giant atrial septal aneurysm (asasFig. 22d-fig:9).


In conclusion, what is justly the right atrial territory is utilized by and functions as the left atrium.

Reference
1. Agmon Y, Khandheria BK, Meissner I, Gentile F, Whisnant .JP, Sicks JD, O'Fallon WhM, Covalt JL. Wiebers DO, Seward JB: Frequency of atrial septal aneurysms in patients with cerebral ischemic events. Circulation 1999;99:1942-1944

 

Atrial Septal Aneurysm: A Study in Five Hundred Adult Patients


Olivares-Reyes Alexander; Al-Kamme Ahmad; Gonzalez JavierCardiology Department The Brooklyn Hospital Brooklyn, New York, USA


Abstract


Introduction:

Today, atrial septal aneurysm (ASA) is well recognized pathology, characterized as a «saccularv deformity, generally at the level of the fossa ovale, which protrudes to the right or left atrium or both. This entity is strongly associated to cardioembolic events as well as other acquired and congenital heart diseases.
Material and Methods: Over a six and one half year period we have prospectively studied clinically and echocardiographically (including transesophageal echocardiogram (TEE) in 200 (40% ) patients), 500 consecutive adults from a total of 22,224 patients (pts) with the diagnosis of ASA.


Results:

We found a prevalence of 2.2%, a mean age of 65 yr. , 317 (63%) women and 183 (37%) men. Clinical associations included, HTN 64%, pulmonary HTN 36%, cerebrovascular events (CVE) 23%, Diabetes 23%, heart failure 16%, atrial arrhythmias 13%, COPD 7%, and chronic renal failure 5%. Echocardiographically: valvular abnormality 86% vs 14% without, left ventricular hypertrophy 44%, PFO 36% (40/110), LA enlargement (LAE) 31%, valvuiar prolapse 13%, RAE 11%, LVE 10%, RVE 8%, atrial septal defect 7 %, vegetations 2.4%, and thrombi 1.2%. The types of ASA were: 1R 16%, 2L 31%, 3RL 12%, 4LR 33%, and type 5, 8% (according to our previously published ASA classification). Mobile ASA 54%, fixed ASA 46%. Left bulging predominance 69% vs 31% right bulging predominance. Type 5 was excluded. Interesting data were found when we analyzed and compared variables like age, gender, type of ASA as well as other concomitant heart diseases. In pts with pulmonary HTN, predominantly left bulging ASA were 114 (69%) vs 52 (31%)* right bulging; COPD 27 (84%) vs 5 (16%)*. In pts with atrial septal defect, predominantly right bulging, 25 (78%) vs 9 (22%)*, while patent foramen ovale pts had left bulging 28 (80%) vs 7 (20%)* of right bulging. (* p <0.05).


Conclusions:

This study supports the commonality in identifying ASA by transthorasic as well as transesophageal echocardiogram. Its definitive association with acquired as well as congenital heart diseases, but also as an isolated and totally asymptomatic entity. Its frequent correlation with cerebrovascular embolic events. It is more prevalent in female, left atrial bulging types of ASA, and a tendency towards the mobile types of ASA.


Introduction


Atrial Septal Aneurysm (ASA) is a localized c<saccular>> deformity of the interatrial septum (IAS), generally at the level of the fossa ovale, which bulges into the right or left atrium or both. ASA was initially thought to be a rare congenital abnormality, however, with the advent of two-dimensional echocardiography and more recently, the widespread use of transesophageal echocardiography (TEE) it has become more easily and more frequently identified in patients.


Prevalence.

The prevalence of ASA varies, but transthoracic echocardiographic (TTE) studies estimate the rate to be between 0.08% and 1.2%. In a large autopsy series the prevalence reported was 1 %. More recent studies using TEE have demonstrated a prevalence between 2% and 10%. In the pediatric patient population the prevalence reported by TTE is 0.9% to 1.7% in children and 4.9% in infants

.
ASA association.

Atrial septa) aneurysm has been associated with congenital heart diseases such as patent foramen ovale (PFO), atrial septal defects (ASD), ventricular septa) defects (VSD), valvular prolapse (VP), patent ductus arteriosus (PDA), Ebstein's anomaly, and tricuspid and pulmonary atresia as well as acquired heart diseases including valvular disease, cardiomyopathy, systemic and pulmonary hypertension, ischemic heart disease, arrhythmias and thrombus formation. More recently a number of studies found an association between ASA and cerebrovascular events (CVE) of embolic origin, including transient ischemic attacks (TIA) and cerebrovascular accidents (CVA).


Objectives


The main objective of this study is to analyze and correlate the clinical and echocardiographic characteristics of patients with this, everyday more diagnosed, cardiac abnormality.


Material and Methods


During the period of January 1991 and June 1997, we studied 22,224 patients which were referred for transthoracic echocardiography. Of these, 500 patients fulfilled the echocardiographic criteria for atria) septal aneurysm.


Echocardiographic examination.

The echocardiographic studies were performed using three commercially available ultrasound systems (Acuson 128, Acuson 128 XP/10c, and Hewlett-Packard sonos 500) with 2.5 to 4 MHz phased array imaging transducers. All systems were capable of both Doppler color and spectral flow. All patients underwent standard TTE views including parasternal long axis, short axis, apical five, four, three, and two chamber views as well as subcostal four chamber and short axis views. The studies were performed with the patient in supine and left lateral decubitus positions during quiet respiration. Particular attention was given to subcostal views with appropriate transducer angulation to visualize the heart completely.


In four chamber view and the interatrial septum with its foramen ovale segment in particular. The atria, including the atrioventricular valves, was magnified to ease the visualization of movement and measurement of the ASA. Patients were placed in the supine position with legs and knees flexed. They were in quiet respiration and sustained inspiration.


Transesophageal echocardiogram was performed in 200 patients with prior TTE studies and who had a diagnosis or suspicion of ASA. All of them had additional indications such as rule-out source of embolism, masses or thrombus, intracavitary shunts, vegetations, etc. TEE was performed after administration of oropharyngeal anesthesia with lidocaine (10%) or aerosolized benzocaine (14%), and occasionally diazepam for sedation. The studies were performed using an Acuson 128 and Acuson 128 XP/10c ultrasound system, with 5-7 MHz single or bi-plane TEE probes. Standard TEE views were obtained.


Contrast study.

Contrast studies were performed during the TEE in patients in whom intracavitary shunt was suspected.
Criteria for atrial septal aneurysm.

The diagnostic criteria for ASA was made if a sacculation or deformity in the interatrial septum or the foramen ovale region was seen. An excursion of = 10 mm into the right or left atrium or if the sum of bilateral excursions of > 10 mm was required. The minimal aneurysmal base amplitude (width) accepted in this study was 15 mm in diameter. The aneurysm was observed in subcostal view, apical four chamber, and parasternal short axis views at the level of the great vessels. Sometimes the bulging was also seen in apical two and three chamber views. The classification of ASA was made according to its different movements, as in previous classifications and regardless of its possibly different etiology. All measurements done in this study were made according to the recommendations of the American Society of Echocardiography. All the studies were taped and hard copies were taken for further analysis and measurements. All cases were reviewed by three different observers.
Statistical analysis. The data were analyzed with Student's t test and chi-square test and are given as mean +- standard deviation. A p value <0.05 was considered significant.


Results


We found an ASA prevalence of 2.2% (500 ASA in 22,224 patients studied in our laboratory during a period of 6 + years.The mean age was 65 years.A predominance in women with 317 Pts.(63%).See Table1(asafig22e-fig10.jpg)below:

All patients with ASA were studied and classified in one of five types of ASA, according to a new classification previously published by us. asaFig22f -fig:11 describes the new classification, while asaFig22g-fig:12 shows the numbers and percentages of patients with the different types of ASA, Patients with left bulging predominance represented the majority with a 64% of the total population and a 69% if compared with the predominantly right bulging type of ASA.

asaFig22f -fig:11:New Classification of Atrial Septal Aneurysm:

Echocardiographic four-chamber view,as well as the different bulgings of the atrial septum with aneurysm, showing the new classification of atrial septal aneurysm and how normally the atrial septum is seen in a two-dimensional depiction.

TYPE 1R: The ASA protrudes from the midline of the atrial to the right atrium throughout the cardiorespiratory cycle.


TYPE 2L: The ASA protrudes from the midline of the atrial septum to de left atrium throughout the cardiorespiratory cycle.


TYPE 3RL: The maximal excursion of the ASA is toward the right atrium with a lesser excursion toward the left atrium.

TYPE 4LR:The maximal excursion of the ASA is toward the left atrium with a lesser excursion toward the right atrium.toward the left atrium with a lesser excursion toward the right atrium.

TYPE 5:The ASA movement is bidirectional and equidistant to the right as well as to the left atrium during the cardiorespiratory cycle.

asaFig22h-fig13:Clinical and echocardiographic variables are described in Table 2 above.
In this study we also analyzed the mobility of the ASA, and we divide them into 2 groups: the <fixed >ASA (types 1R and 2L, which only bulge within an atrium) 231 Pts. (46%), and the <mobile> ASA (types 3RL, 4LR, and Type-5, which bulge bidirectionally into both atria), 269 Pts. (54%),asaFig22h-fig13.

A highlight of these variables are represented in asaFig22i-fig14. In patients with pulmonary HTN, predominantly left bulging ASA were 114 (69%) vs 52 (31 %) right bulging; COPD 27 (84%) vs 5 (16%); PFO 28 (80%) vs 7 (20%). In the other hand, patients with ASD had predominantly right bulging in 25 (78%) vs 9 (22%)of left bulging. ('p< 0.05).

Discussion


ASA is becoming more prominent in clinical cardiology. Its association with cardiac abnormalities, in particular cardiogenic embolic events, contributes to its significance. Only about 100 cases of ASA had been reported before 1985; however, in the last 10 years, and because of new and better 2D echo machines and TEE, a considerable number of cases has been published. To date, this is the largest casuistic study of patients with ASA. The association of ASA with clinical variables like CVE, HTN, CAD, DM, valvular prolapses, arrhythmias, valvulopathies, PFO, ASD, etc., is identified in this large group of patients like can be observed in Table 2.


An Echo with an ASA type 1 R is represented in asafig22j-fig15.jpg. This is an amplified 4C subcostal view of a 65 yr old lady with history of CHF and moderate mitral regurgitation.

 

Conclusions

From this study we can conclude: 1) the commonality in identifying ASA by TTE and TEE, 2) Its association with acquired as well as congenital heart diseases, 3) that there is a group of patients with isolated and asymptomatic ASA, 4) Its frequent association to stroke, 5) the left predominance type and mobile ASA., and 6) the tendency to be more frequent in female patients.


References

1. Olivares-Reyes A, et at. Atrial Septal Aneurysm: A new classification in 205 adults. J Am Soc Echocardiogr 1997:10:644-56.
2. Silver MD, Dorsey JS. Aneurysm of the septum primum in adults. Arch Pathol Lab Med 1978;102:62-5.
3. Henley PC et al. Diagnosis and classification of atrial septa) aneurysm by two-dimensional echocardiography: report of 80 consecutive cases. J Am Coll Cardiol 1985;6:1370-82.
4. Longhini C, et al. Atdal septet aneurysm: echocardiographic study. Am J Cardiol 1985;56:653-67,
5. Mugge A, et al. Atrial septet aneurysm in adult patientsi a multicenter study using transthoracic and transesophageal echocardiography. Circulation 1995;19:2785-92.
6. Hauser AM, et al. Aneurysm of the atria) septum as diagnosed by echocardiography: analysis of 11 patients. Am J Cardiol 1984;53:1401-2.
7. Gondi B, Nanda NC. Two-dimensional echocardiographic features of atria) septa aneurysm. Circulation 1981,63:452-57

2) Cyanotic Congenital Heart Disease

This group features bluish discoloration of the skin and lips as opposed to the normal pink appearance. The cyanosis is due to the shunting of systemic venous blood to the arterial circulation causing arterial blood desaturation of oxygen.

The size of the shunt determines the degree of desaturation.

In adults the most common causes of cyanotic congenital heart disease are tertralogy of Fallot and Eisenmenger's syndrome.

1.Tetralogy of Fallot

It is characterized by a large ventricular septal deftect (VSD), an aorta that overrides the left and right ventricles, obstruction of the right ventricular (RV) outflow tract, and RV hypertrophy (increased wall thickness).

As obstruction in RV outflow tract increases, more blood is shunted through the VSD to the left side of the heart to cause more cyanosis (see figure 23c).

Increases in resistance to flow in the general arteries of the body causes less shunting, and decreases cause more shunting to the left.

Symptoms in adults include shortness of breath and limited exercise tolerance.

Complications include brain abscesses, strokes and heart infections.

Such patients may have enlargement of the distal ends of their fingers called clubbing.

Most patients without surgical correction die in childhood.

Echocardiography can establish the diagnosis. Color Doppler can visualize the VSD.

Heat catherterization can confirm the diagnosis.

Surgical repair is recommended to relieve symptoms and to improve survival.

Complete surgical correction (closure of the VSD and relief of RV outflow obstruction is performed currently when patients are very young.

Patients are at risk for heart infections and should thus receive prevention with antibiotics before dental or elective surgical procedures.

Even with repair these patients have a poorer survival rate (apparently due to cardiac causes such as arrhythmias).

2. Ebstein's Anomaly

This anomaly is due to a defect in the tricuspid valve (TV) with the septal and posterior leaflets displaced down into the right ventricle, while the anterior leaflet is malformed and abnormally attached to the RV free wall (see figure 23d).

This valve often allows blood to regurgitate from the small RV back into the large RA.

Eighty percent of these patients have ASD's through which right-to-left shunting of blood may occur with cyanosis.

Such patients are at risk for a paradoxical embolus (blood clot) from the RA through the LA to the brain with abscess, and sudden death.

There is usually a heart murmur.

EKG abnormalities are often present including WPW syndrome (see figure 1, figure 2 and figure 3).

Twenty percent have an accessory electrical pathway between the atrium and ventricle (see figure 1).

Echocardiogram can define the abnormalities, and a color Doppler imaging can determine the presence and size of interatrial shunting.

Management involves prevention of complications, such as heart infection, prevented with antibiotic prophylaxis.

Heart failure is treated with diuretics (diuril, lasix, etc) (to eliminate fluid) and digoxin (a heart drug to improve heart muscle contractions).

Arrhythmias may be treated with medication or catheter ablation (see figure 11).

Repair or replacement of TV in conjunction with closure of the interatrial communication is recommended in older patients with severe symptoms despite medical therapy and heart enlargement.

3. Transposition of the Great Arteries

In d-transposition of the great arteries, the aorta arises in an anterior position from RV and the pulmonary artery arises from LV (see figure 23e).

In two thirds of cases the ductus arteriosus (see figure 22) and foramen ovale allow communication between the aortic and pulmonary circulations.

Severe cyanosis is present.

The one third with other defects that permit intracardiac mixing (i.e. ASD figure 20, VSD figure 21, PDA) are less critically ill with loss severe cyanosis, but they are at risk of LV failure.

Findings include cyanosis and heart murmur.

RVH (RV wall enlargement) or LVH (LV wall enlargement) may be present. Chest X ray shows heart enlargement.

Immediate management involves creating intracardiac mixing or increasing its extent:

1) use of infusing of medication, prostaglandine E to maintain or restore patency of ductus arterioses, the creation of an ASD or both.

Also, oxygen is administered to most patients (to decrease pulmonary [lung] vascular (blood vessel) resistance and to increase lung blood flow), as are digoxin and diuretic drugs like diuril or lasix (to treat heart failure).

Figure 23e

Two surgical operations have been used (see figure 23e regarding the atrial switch operation).

The atrial switch operation as shown in figure 23e has been replaced by the arterial switch operation in which the pulmonary artery and ascending aorta are transected above the semilunar valves and coronary arteries (see figure 23e), and then switched, so that the aorta is connected to the neoaortic valve (formerly the pulmonary valve) arising from the left ventricle (LV), and the pulmonary artery is connected to the neopulmonary valve (formerly the aorta valve) arising from the RV (see figure 23e).

The coronary arteries are relocated to the neoaorta to restore normal coronary circulation.

This operation can be performed in neonates (newly born) and is associated with a low operative mortality and an excellent long-term outcome.

4. Esenmenger's Syndrome

This consist of a large left (L) to right (R) shunt, which causes severe pulmonary (lung) vascular disease and high blood pressure (in the lungs) with resulting reversal of the direction of shunting ( figure 23f ).

This shunting with increase pressure causes the lung arteries to narrow due to thickening of their walls (especially the middle wall, called tunica media, see figure 23f) and cause obstruction.

Initially the changes may be reversible, but ultimately they become irreversible due to inflammation of the arteries.

Hence, much of the lung arteries are occluded, leading to increase pulmonary blood vessel resistance. Ultimately the resistance in the lungs may exceed the resistance in the arteries of the rest of the body, which leads to a reversal of flow from left-to-right to right-to-left shunt.

The reversal of the shunt leads to cyanosis, as well as shortness of breath, coughing up blood, reduced exercise tolerance, syncope (fainting), palpitations, and atrial fibrillation (see figure 15a, figure 15b).

Brain events such paradoxical embolus, thrombosis (stroke) and hemorrhage may occur.

Heart failure suggest a poor prognosis, and sudden death is possible.

Digital swelling (clubbing) may occur. Heart murmurs may occur.

EKG may show RVH and atrial arrhythmias (see figure 2, figure 3, figure 4 and figure 5).

Echocardiogram shows RV pressure overload, pulmonary high blood pressure, and the underlying heart defect.

Using intravenous contrast injections along with echocardiogram will visualize the intracardiac defect. Heart catherterization is necessary to assess the lung hypertension and the size of the defect.

Rate of survival is 80% 10 years after diagnosis, 77% at 15 years, and 42% at 25 years. Death is usually sudden, presumably due to arrhythmias, but some die of the above mentioned complications.

Lung transplantation with repair of the cardiac or combined heart-lung transplantation is an option for patients with a poor prognosis (failing to respond to medical therapy).