The importance of increased interatrial septal thickness in patients with atrial fibrillation: a transesophageal echocardiographic study

BACKGROUND: Histological studies in animal models have showed that extensive atrial fibrosis or fatty deposition as a result of loss of atrial cardiomyocytes increases the propensity to develop atrial fibrillation (AF). Although several reports have suggested that AF in humans may be a consequence of these mechanisms, no study has correlated the presence of AF with interatrial septal thickness (IAST). METHODS: Accordingly, we conducted a prospective analysis in 150 consecutive patients referred for transesophageal echocardiography (TEE) for numerous medical reasons. A total of 105 patients (mean age 62 +/- 14 years) who met inclusion and exclusion criteria were included for analysis. Pertinent demographics, echocardiographic chamber dimensions, left ventricular ejection fraction (LVEF), color flow, and spectral Doppler analysis, as well as IAST measured in both systole (S) and diastole (D) were obtained. RESULTS: When patients with a documented history of AF were compared to patients without documented AF, no statistical difference was noted in terms of patients' height, weight, IVS thickness, or LVEF. Patients with AF had a significantly larger left and right atrial dimensions (P < 0.001), lower left atrial appendage emptying velocities (P < 0.002), and pulmonary vein systolic Doppler signal (P < 0.01). The IAST in systole in patients with AF was 0.75 +/- 0.27 cm versus 0.60 +/- 0.16 cm in patients without AF (P < 0.006) while the IAST in diastole was 0.61 +/- 0.22 cm versus 0.49 +/- 0.12 cm, respectively (P < 0.009). However, no statistical difference was noted between IAST in either systole (P < 0.8) or diastole (P < 0.8) among patients with AF based on the duration of this arrhythmia. CONCLUSIONS: The results of this prospective TEE study show a statistically significant increase in IAST with the presence of AF independent of patient's age, height, weight, and the degree of IVS thickness. In addition, since no significant valvular abnormalities or compromise in left ventricular systolic function were present, the increase in IAST in patients with AF then suggest possible changes in the material properties of the atrial wall, easily identified by TEE on the interatrial septum, either as a cause or as a result of AF. Since no correlation was found between the degree of IAST and the duration of AF, the presence of IAST not only might identify patients with a higher propensity to have or develop this atrial arrhythmia; but also be a surrogate marker of changes within the components of the atrial wall in AF.     

A large epicardial lipoma--an insight into the surgical anatomy of the interatrial septum

A large epicardial lipoma was successfully resected. Consideration of the origin of this tumour gives an insight into the surgical anatomy of the interatrial septum.     

Atrial septal aneurysm and stroke: a transesophageal echocardiographic study

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.     

Electrostimulation of the interatrial septum

The first clinical experience of the successful application of electrostimulation of the atrial septum is described. Sickle-shaped electrodes were used for this purpose. Electrostimulation of the atrial septum was medically indicated in all cases. In 2 cases the electrode was fixed to the atrial septum after open-heart surgery and in 3 cases it was done because of an excessively high threshold of cardiac electrostimulation. Sickle-shaped electrodes are shown to be the most optimal for continuous electrostimulation of the atrial septum.     

Aneurysm of the interatrial septum and right-to-left shunt during biventricular infarction. Diagnosis by transesophageal echocardiography

A right-to-left shunt during infarction with right ventricular extension is a rare and recently described complication. It results from opening of a foramen ovale due to increased right heart pressures. The authors describe another case occurring in a patient with an interatrial septal aneurysm, the diagnosis of which was made by transoesophageal echocardiography.     

Diagnostic criteria of interatrial defects: a single gate pulsed Doppler echocardiographic study

Functional closure of the oval foramen occurs during the first days of life. Nevertheless, range-gated pulsed Doppler echocardiography shows a transatrial flow pattern in many newborns. In this situation, cross-sectional echocardiography often fails in differentiating the valve-incompetent oval foramen from an atrial septal defect. In order to establish Dopplersonographic criteria for these diagnoses, we performed a prospective echocardiographic and pulsed Doppler study in 34 newborns with valve-incompetent oval foramen and in 30 children with atrial septal defect. We could not find any significant difference of flow pattern in either group, although a so-called "flap" signal could be demonstrated in 73.5% of the patients with an oval foramen, but in only 23% of the children with atrial septal defect. We suggest this feature reflects a distinct movement of the flap of oval foramen which passively follows the different interatrial pressure-flow dynamics. Nevertheless, this sign was insufficiently constant to prove presence of an oval foramen and not that specific to exclude an atrial septal defect. We conclude, therefore, that the precise nature of interatrial defects cannot be differentiated by single gate pulsed Doppler echocardiography.     

Lipomatous hypertrophy of the interatrial septum

Lipomatous hypertrophy of the interatrial septum is a rare conditionand it does not require any specific treatment. We present thetransoesophageal echocardiogram findings of a 70-year-old ladydemonstrating the appearances that were typical of lipomatoushypertrophy of the interatrial septum.     

Lipomatous hypertrophy of the interatrial septum

The mechanism of pseudoaneurysm formation caused by prolonged sepsis is thought to be related to the vascular endothelium being directly invaded and broken by bacteria. Moreover, matrix metalloproteinases (MMPs) which are up-regulated by chronic inflammation have been reported to be implicated in the pathogenesis of aneurysm development through increased proteolysis of extracellular matrix proteins. An effective treatment for infected pseudoaneurysm remains unsettled. Surgery is generally performed, however, because the patients in most of these cases are in very poor physical condition, the operation is associated with high morbidity and mortality. A more successful alternative is endovascular treatment. Recent reports indicate low morbidity and mortality rates with this treatment. If the patient in this case had been in better condition, we could have selected endovascular stent-grafting for her treatment.     

The case of a cyst hydatid localized within the interatrial septum

The ratio of cardiac involvement of Echinoccocus granulosus is 0.02-2% and although seen rarely, involvement of the interatrial septum has also been reported in the published literature. The present case was a 19-year-old male university student admitted to hospital with complaints of headache and dizziness. Computerized tomography of the cranium revealed a cystic mass located at the frontal region and enucleation of the cyst was performed during surgery. A cystic lesion 5 x 4 cm in size was detected within the interatrial septum on two-dimensional transthoracic echocardiography during the postoperative period and the patient was referred to our clinic. Open heart surgery was performed and a hydatid cyst that involved the interatrial septum was enucleated. The cyst wall was sutured to the interatrial septum. No complications developed during the postoperative period. The patient was discharged on the fifth day of hospitalization and medical therapy was started with albendazole.     

Primary antiphospholipid syndrome: a 5-year transesophageal echocardiographic followup study

OBJECTIVE: To study valvular abnormalities in patients with primary antiphospholipid syndrome (APS) assessed by transesophageal echocardiography (TEE). METHODS: This was a 5-year followup study. Between 1995 and 1997, 29 consecutive patients with primary APS were studied by TEE. Twenty-four patients were evaluated in our institution and 5 were referred from elsewhere. Four patients had died, 12 patients had the 5-year followup TEE, and 8 failed to report for the study. RESULTS: In the first TEE, valve lesions were found in 17 patients (70.8%), myocardial infarction in 5 cases (29.4%), pulmonary hypertension in 4 (23.5%), and a calcified thrombus in the right atrium in one patient. Five-year followup TEE was performed in 12 patients. Valve lesions were unchanged in 3 cases, and in one of them a new apical akinesis of the left ventricle appeared. New valve lesions were detected in 3 patients. In 6 patients, the valve lesions had progressed and in 2, abnormalities of ventricular wall motion had appeared. CONCLUSION: In this highly selected population of patients with primary APS, the predominant cardiac lesion was a noninfective valve lesion. Oral anticoagulant treatment and aspirin proved ineffective in terms of valvular lesion regression. Altogether, myocardial infarction occurred in 9 (37.5%) patients. All had coronary angiography and coronary arteries were normal in 6.     

Catecholamine-secreting paraganglioma of the interatrial septum

A 29-year-old woman was found to have clinical and biochemical evidence of a functioning paraganglioma (pheochromocytoma) five years after the onset of symptoms. Despite extensive investigation of known potential sites of paragangliomas (including laparatomy), the suspected tumor eluded localization. Adrenergic blocking agents controlled her blood pressure but did not affect the other manifestations of catecholamine excess. Ischemic perforation of the colon and refractory gram-negative sepsis resulted in death. At autopsy, a large paraganglioma was found within the heart; the unique tumor location was an important factor in the fatal clinical course.     

Cardiac troponin I release after transcatheter closure of the interatrial septum: a prospective study

OBJECTIVE: To identify cTnI rise after percutaneous ISD closure and to determine its prognostic significance. BACKGROUND: Cardiac troponin-I (cTnI) is a very specific and sensitive marker of myocardial injury. A significant increase of cTnI levels after percutaneous interatrial septal defect (ISD) closure has been reported. METHODS: Patients admitted for transcatheter atrial septal defect (ASD) and patent foramen ovale (PFO) closure, were enrolled in this prospective study. Standard protocol was unchanged, except for blood sampling, to which serial cTnI before, 6, and 24 hours after the procedure was added. RESULTS: Seventy-eight patients (female/male 37/41, mean age 55 +/- 13 y, 14 ASD and 64 PFO) were included. In none of the patients cTnI was elevated before the procedure and in no patients a cTnI rise above the WHO-criteria for myocardial infarction (> = 0.4 ng/ml) was seen. However, in 32 patients (41%) minimal cTnI rise (range from 0.04 ng/ml to 0.37 ng/ml) was present within a time frame of 24 hours. The increase in cTnI was not related to peri-procedural complications and to short-term outcome (mean follow-up time of 7 +/- 5 months). In addition, cTnI rise was significantly related with the presence of hyperlipideamia (P = 0.004), device size (P = 0.008), and the absence of balloon sizing (P = 0.017). CONCLUSIONS: Transcatheter closure of ISD seems to be a safe procedure. A minimal but significant increase of cTnI is noted in some patients after the procedure, but it seems not to be related to short-term prognosis. However, cTnI rise is clearly associated with patients' characteristics and peri-procedural variables.