Thickness Of Interatrial Septum Research Articles

Characterization of the interatrial septum by high-field cardiac MRI: a comparison with multi-slice computed tomography

BackgroundAssessment of the interatrial septum (IAS) has become an attractive area of interest for a variety of important interventional procedures. Newer imaging modalities like multi-slice computed tomography (MSCT) and cardiac MRI (CMR) can provide higher resolution and wider field of view than echocardiography. Moreover, high-field (3-Tesla) CMR can even enhance spatial and temporal resolution.The characteristics of the interatrial septum were retrospectively studied in 371 consecutive subjects (201 men, 31–73 years old) in whom MSCT was performed primarily for non-invasive evaluation of the coronary arteries. All subjects underwent both MSCT and MRI scans within 0–30 day’s interval. A 3D volume covering the whole heart was acquired across the heart with and without contrast enhancement. Also, patients underwent cardiac MSCT examinations using 64-row MSCT scanners.ResultsThe mean scan time of MSCT was 10.4 ± 2.8 s and 9.7 ± 2.9 min for CMR. The mean length of IAS by CMR and CT was 39.65 ± 4.6 mm and 39.28 ± 4.7 mm, respectively. The mean maximal thickness of IAS by CMR and CT was 3.1 ± 0.97 mm and 3.15 ± 0.95 mm, respectively. The mean thickness of fossa ovalis by CMR and CT was 1.04 ± 0.36 mm and 1.04 ± 0.44 mm, respectively. The mean length of fossa ovalis by CMR and CT was 12.8 ± 3.7 mm and 12.8 ± 3.5 mm, respectively. Finally, the mean angle of IAS by CMR and CT was identical (155 ± 9.2°). Measurements of various morphological features of IAS showed no statistically significant difference between CMR and CT, with an excellent correlation and close relationship regarding IAS length, maximal IAS thickness, fossa ovalis thickness, fossa ovalis length, and IAS angle (r = 0.98, 0.98, 0.95, 0.96, and 0.92, respectively).ConclusionWhole-heart 3D acquisition at 3-T MRI using a free-breathing technique provides a valuable non-invasive imaging tool for excellent assessment of the interatrial septum—as compared to MSCT—that may have significant clinical implication for diagnostic purposes and therapeutic interventional procedures, as it may facilitate planning, improve outcome, and shorten its duration.

Decreased left atrial global longitudinal strain predicts the risk of atrial fibrillation recurrence after cryoablation in paroxysmal atrial fibrillation.

We aimed to investigate the association of atrial fibrillation (AF) recurrence with left atrial (LA) strain in nonvalvular paroxysmal AF patients after cryoablation. We included 190 patients who underwent successful cryoablation due to paroxysmal AF. In addition to classical echocardiographic data, LA apical 2-chamber (A2C) strain, LA apical 4-chamber (A4C) strain, and LA global longitudinal strain (LA-GLS) values were calculated by speckle tracking echocardiography. Forty-eight-hour Holter monitoring was performed to all patients no later than 6months after ablation. AF recurrence was detected in 42 patients (22.1%). End-systolic diameter, LA end-systolic diameter, LA-volume, LA-volume index, interatrial septum thickness, coronary sinus diameter, epicardial fat thickness (EFT), and septal E/E` ratio were significantly higher, LV-EF, IVRT, septal S and A` wave, lateral S wave, LA-A2C strain, LA-A4C strain, and LA-GLS were significantly lower in patients with AF recurrence. LA-GLS, LA-volume index, and EFT were found to be independent parameters for predicting AF recurrence. LA-GLS and LAVI should be included in routine evaluations to determine long-term AF recurrence preoperatively.

TCTAP A-090 Association of Interatrial Septal Thickness with Severity of Coronary Artery Disease

Paracrine effect of the epicardial adipose tissue may promote coronary atherosclerosis. Adipose tissue is the main determinant of interatrial septum thickness (IST) and is a true marker of cardiac adiposity. The relationship of IST with the presence and severity of coronary artery disease (CAD) is

Interatrial block and interatrial septal thickness in patients with paroxysmal atrial fibrillation undergoing catheter ablation: Long-term follow-up study.

Interatrial block (IAB) is a strong predictor of recurrence of atrial fibrillation (AF). IAB is a conduction delay through the Bachman region, which is located in the upper region of the interatrial space. During IAB, the impulse travels from the right atrium to the interatrial septum (IAS) and coronary sinus to finally reach the left atrium in a caudocranial direction. No relation between the presence of IAB and IAS thickness has been established yet. To determine whether a correlation exists between the degree of IAB and the thickness of the IAS and to determine whether IAS thickness predicts AF recurrence. Sixty-two patients with diagnosis of paroxysmal AF undergoing catheter ablation were enrolled. IAB was defined as P-wave duration ≥120ms. IAS thickness was measured by cardiac computed tomography. Among 62 patients with paroxysmal AF, 45 patients (72%) were diagnosed with IAB. Advanced IAB was diagnosed in 24 patients (39%). Forty-seven patients were male. During a mean follow-up period of 49.8±22months (range 12-60months), 32 patients (51%) developed AF recurrence. IAS thickness was similar in patients with and without IAB (4.5±2.0mm vs. 4.0±1.4mm; p=.45) and did not predict AF. Left atrial size was significantly enlarged in patients with IAB (40.9±5.7mm vs. 37.2±4.0mm; p=.03). Advanced IAB predicted AF recurrence after the ablation (OR: 3.34, CI: 1.12-9.93; p=.03). IAS thickness was not significantly correlated to IAB and did not predict AF recurrence. IAB as previously demonstrated was an independent predictor of AF recurrence.

Comparison of different types of cardiac amyloidosis by cardiac magnetic resonance imaging

Objectives: We sought to determine cardiac morphological and functional differences between light-chain (AL), mutant-type transthyretin (ATTRmt) and wild-type TTR (ATTRwt) amyloidosis using contrast-enhancement cardiac magnetic resonance imaging (CE-CMR). Finally, we attempted to establish the diagnostic and prognostic impact of these findings. Introduction: The most common forms of cardiac amyloid are AL and ATTR amyloidosis, but the clinical courses of these variants are quite heterogeneous. While CE-CMR is used to evaluate patients with cardiac amyloidosis, its ability to predict prognosis in these patients is debatable.Methods: About 130 patients with cardiac amyloidosis (AL, n = 62; ATTRmt, n = 30, ATTRwt, n = 33) were assessed by CE-CMR (cardiac morphology, cardiac function, late gadolinium enhancement).Results: Left ventricular (LV) mass, basal and mid-ventricular maximal wall thickness, and thickness of the inter-atrial septum were higher in ATTRwt when compared to AL and ATTRmt amyloidosis. Tricuspid annular excursion was lower in ATTRwt amyloidosis than in AL amyloidosis. CE was observed in 94.6% of the patients (AL 80.6%; ATTRmt 90%; ATTRwt 87.9%) with significant differences in quality and intensity between the groups. Differentiation of amyloid types was achieved by combination of age, number of organs, the presence of inferolateral CE-CMR, thickness of inter-atrial septum and troponin T. Overall 1-year-survival rates were 93.3, 93.9 and 70.5% in ATTRwt, ATTRmt and AL amyloidosis, respectively. LV mass, mitral annular excursion and NT-proBNP in AL amyloidosis, LV mass maximal apical wall thickness and troponin T in ATTRwt amyloidosis, and finally NT-proBNP and renal function in ATTRmt amyloidosis were independent predictors of outcome.Conclusions: This study demonstrates that CE-CMR can highlight morphological and functional differences between different types of cardiac amyloidosis. In addition, CE-CMR and cardiac biomarkers provide useful prognostic information in patients with cardiac amyloidosis.

Thickness of the midventricular left ventricular wall is predictive of survival in different forms of cardiac amyloidosis

Background Systemic amyloidosis is a disorder characterized by extracellular deposition of different insoluble protein fibrils in various organs leading to organ dysfunction. Cardiac involvement is associated with limited survival. We aimed to use cardiac magnetic resonance imaging (CMR) to identify structural and functional alterations related to the different forms of amyloidosis, e. g. hereditary and wild-type transthyretin (TTR) amyloidosis as well as light-chain (AL) amyloidosis. Methods In total, 130 patients (82 male, 38 female; mean age 60.7 ±1.1 years) with different forms of amyloidosis (AL n= 72, TTR n=58) were evaluated by two blinded experienced observers employing a Vector-ECG gated 1.5T wholebody CMR (Achieva Intera ® Philips Medical Systems, Best, The Netherlands). The study included SSFP and gadolinium contrast delayed enhancement (CE-CMR) 2,3-,4-chamber and short-axis planes. EDV, ESV, EF and myocardial mass were analyzed on a standard workstation (Philips Viewform). Regional wall thickness was analyzed in modified 16 segment AHA-model of the left ventricle as well as the interatrial wall and compared between the different forms of amyloidosis. Univariate and multivariate analysis were performed to define predictors of survival. Results Patients with TTR amyloidosis were significantly older as compared to patients with AL. They had higher left ventricular mass (171.9±8.1g vs. 146.1±6.9g, p<0.01) and thickness of interatrial septum (7.3±0.3mm vs. 5.7±0.2mm; p<0.001) with highest LV mass and thickness of interatrial septum in patients with wild-type amyloidosis (n=26). Distribution of regional wall thickness is shown in figure 1. In AL patients univariate analysis revealed median of maximal wall thickness of the basal (14 mm), midventricular (10 mm) and apical (7 mm) segments as predictors of survival. In multivariate analysis midventricular maximal wall thickness was the only independent predictor of survival. In TTR patients univariate analysis revealed median of maximal wall thickness of the midventricular (13.5 mm) and apical (8 mm), but not basal (16.0 mm) segments as predictors of survival. There was no independent predictor of survival in multivariate analysis of these patients.

Interatrial Septal Thickness as a Marker of Structural Remodeling of the Left Atrium in Patients with Atrial Fibrillation

Background: Although periatrial adipose tissue, especially in interatrial septum, has been known to be related with atrial fibrillation (AF) chronicity, the association between interatrial septum thickness (IST) and atrial remodeling has not been elucidated. Objective: The aims of the present study are to determine whether IST correlates with structural remodeling of the left atrium (LA), and to identify whether it predicts clinical outcome after catheter ablation (CA) for AF. Methods: We consecutively enrolled 104 patients undergoing CA for AF [paroxysmal AF (PAF)=82, persistent AF (PeAF)=22]. An echocardiography and voltage mapping using NavX system were performed. LA was divided into 6 segments and the mean voltage for each region was determined by averaging the bipolar voltage of the points. IST and integrated backscatter signal (IBS) reflecity of interatrial septum were assessed. Results: IST was significantly correlated with the mean voltage of LA (r=−0.537, p<0.001), IBS reflecity (r=0.476, p<0.001), LA volume index (LAVI) (r=0.203, p=0.038), and CHA2RD2-VASc score (r=0.348, p<0.001). During the mean follow-up of 17 months after a single ablation procedure, 27 subjects (26.0%, PAF=20, PeAF=7) had arrhythmia recurrence. Multivariate analysis revealed that LAVI, IBS, and IST were independent predictors for AF recurrence after CA. Conclusion: IST was a reliable non-invasive parameter for structural remodeling of the LA and might predict thromboembolic risk.

Interatrial Septum Thickness and Difficulty with Transseptal Puncture during Redo Catheter Ablation of Atrial Fibrillation

Patients undergoing catheter ablation for atrial fibrillation (AF) frequently require redo procedures, but there are no data reporting interatrial septum thickness (IAS) and difficulty during repeat transseptal puncture (TSP). Patients undergoing two separate AF ablation procedures had preprocedural fossa ovalis (FO) thickness measured using transesophageal echocardiography (TEE). "Difficult" TSP was defined by two observers as requiring excessive force, or conversion to TEE guidance. The study comprised 42 patients (37 male) with mean+/-SD age 55+/-9 years. Mean FO thickness was significantly greater at the time of redo TSP (2.2+/-1.6 mm vs 2.6+/-1.5 mm at redo, P=0.03); however, this finding was limited to those who underwent initial dual transseptal sheath procedures, FO thickness 2.0+/-1.5 mm and 2.5+/-1.4 mm for TEE 1 and 2, respectively (P=0.048). There was a trend for more frequent difficult redo TSP procedures, 7/42 (17%; 95% confidence interval [CI] 8-31) redo, versus 4/42 (10%; 95% CI 3-23) first TSP. On univariate analysis, FO thickness was not predictive of TSP difficulty; the only predictor of difficult redo TSP was diabetes. IAS thickness at the FO increased following catheter ablation of AF, yet on subgroup analysis this was limited to initial procedures utilizing dual transseptal sheaths. There was a trend toward more frequent difficulty during redo TSP, yet this was not associated with FO thickening. Diabetes may predispose to difficulty during redo TSP; this finding requires confirmation in a larger study population.

Morpho-functional assessment of interatrial septum: a transesophageal echocardiographic study

Background: Despite the increasing number of reports on lipomatous hypertrophy of interatrial septum, a standardization of measurement of the dimensions of the interatrial septum (IAS) in the different phases of cardiac cycle has not been reported. Moreover, no data on modification of thickness with age and in specific cardiac diseases are available. Objective: Our purpose was to study whether the changes of thickness and thinning of IAS may be related to age, left atrial dimension, cardiac cycle and different cardiac diseases. Methods: 248 patients (mean age 52.7 ± 19.9 years) underwent transthoracic (TTE) and transesophageal (TEE) echocardiography. IAS was measured at the constant regions anterior and posterior to the fossa ovalis. IAS thickness (tk), thinning (th) and % thinning (% th) were measured. Results: IAS thickness ranged from 4 to 13 mm at the time of ventricular end-systolic phase (mean 6.7 ± 1.9 mm) and from 6 to 16 mm at the time of atrial systole (mean 9.9 ± 1.8 mm); significant statistical difference between these values was found ( P < 0.01). IAS thinning ranged from 1 to 7 mm (mean 3.42 ± 1.8) while % IAS thinning from 18 to 76% (mean 36.53 ± 16.36%). Statistical analysis showed a significant positive correlation between age and ventricular end-systolic thickness and atrial systolic thickness and thinning. An insignificant correlation was found between age and % IAS thinning and between left atrial dimension and IAS tk and th. Conclusions: Our results demonstrate that IAS thickness increases by age; no correlation exists between IAS thinning and age. There is no difference between IAS thickness and thinning in patients with or without cardiac disease. We believe that the thickness of IAS can be considered hypertrophic only if it exceeds the value of 15 mm during both ventricular end-systolic and atrial systolic phases of the cardiac cycle. IAS thickness and thinning might be an additional parameter to evaluate systolic atrial function particulary with regard to maintenance of synus rhythm after conversion from atrial fibrillation as well as to better understand its role in determining the filling of ventricles in different clinical conditions.