Left Atrial Diverticula Research Articles

Atrial anatomical variations on computed tomography angiography associated with atrial fibrillation and those predicting recurrence following pulmonary vein isolation

Abstract Background We aim to investigate the atrial anatomical variations in patients with and without atrial fibrillation (AF) using cardiac-computed tomography angiography (CCTA) and identify features associated with AF recurrence following pulmonary vein isolation. Materials and Methods We retrospectively reviewed 502 CCTAs of patients with AF performed prior to a pulmonary vein isolation procedure with 1058 CCTAs of patients without AF performed to rule out coronary artery disease between 2014 and 2017. Anatomical variations of both atria including left atrial diverticula (LAD), right atrial diverticula (RAD), Bachmann bundle shunt (BBS), and pulmonary vein anatomy were assessed. Results We found that patients with AF were older (67 ± 14 vs 63 ± 13 years, P = .039), had a higher prevalence of diabetes (24.4%) versus (14.7%), P = .006, and cerebrovascular accidents (3.8%) versus (0.9%), P = .044 when compared with patients without AF. Furthermore, on CCTAs patients with AF demonstrated a significantly higher prevalence of BBS (11% vs 4.1%, P < .001), LAD (19% vs 7.7%, P < .001), and RAD (9.8% vs 2.1%, P < .001) when compared to patients without AF. Logistic multivariable regression analyses of CCTA findings demonstrated increased odd ratios (OR) in those with AF of BBS (OR = 3.51, 95% CI, 2.32-5.35, P < .001), LAD (OR = 2.94, 95% CI, 2.12-4.07, P < .001), RAD (OR = 1.54, 95% CI, 1.19-2.11, P = .03), LA diameter (OR = 2.42, 95% CI, 1.65-3.39, P < .001). Importantly, multivariate Cox regression showed that the LA dimension is a predictor of AF recurrence (HR = 1.019, 95% CI, 1.001-1.051, P = .02). Conclusion AF patients have a higher prevalence of BBS, LAD, and RAD in comparison to patients without AF. Mean LA diameter predicts AF recurrence after the pulmonary vein isolation procedure.

Abstract 14789: Atrial Anatomical Variations Between Atrial Fibrillation Patients Compared to Other Subjects Without Atrial Fibrillation

Introduction: In this study, we evaluated the anatomical atrial variations using gated cardiac computed tomography (CCT) between patients with and without atrial fibrillation (AF). Hypothesis: The aim of the study is to evaluate if there are specific anatomical characteristics that are associated with poor clinical outcomes following ablation in patients with AF. Methods: We retrospectively included 502 CCT scans of patients with AF prior to their pulmonary vein isolation procedure, and 1058 CCT scans of patients without AF performed to evaluate pulmonary vein anatomy and to rule out coronary artery disease between 2014 to 2017. Anatomical variations of the atria and interatrial septum included the Bachman bundle shunt (BBS - defined as a vascular channel crossing between the atria through the Bachman bundle), and atrial diverticulae. Results: Five-hundred and two patients with AF were older (67±14 vs. 63±13 years, P = 0.039), had a higher prevalence of diabetes mellitus (24.4% vs 14.7%, p = 0.006), and cerebrovascular disease (3.8% vs. 0.9%, p = 0.044) compared to patients without AF. Furthermore, CCTs analysis of AF patients demonstrated a significantly higher prevalence of BBS: (11% vs 4.1%, p <0.0001, left atrial diverticula (19% vs 7.7%), p <0.0001, and right atrial diverticula (9.8% vs 2.1%), P <0.0001 compared to patients without AF. Conclusions: This study is the first to analyze BBS and atrial diverticular prevalence in patients using CCT. We found that patients with AF are associated with a higher prevalence of structural atrial abnormalities including BBS, left and right atrial diverticula in comparison to individuals with no previous history of AF. Whether these anatomical variations influence AF incidence or AF recurrence after catheter ablation is yet to be determined.

Association between pouch morphology, cardiovascular risk factors and ischemic brain lesions in patients with left-sided septal pouches

BackgroundLeft atrial outpouching structures such as left atrial diverticula (LADs) and left-sided septal pouches (LSSPs) might be a source of cryptogenic stroke. This imaging study evaluates the association between pouch morphology, patient comorbidities and ischemic brain lesions (IBLs). MethodsThis is a retrospective single-center analysis of 195 patients who received both a cardiac CT and a cerebral MRI. LADs, LSSPs, and IBLs were retrospectively identified. Size measurements included pouch width, length and volume for LADs and circumference, area and volume for LSSPs. The association between LADs/LSSPs, IBLs and cardiovascular comorbidities was determined by univariate and bivariate regression analyses. ResultsThe prevalence and mean volume were 36.4% and 372 ± 569 mm3 for LSSPs, and 40.5% and 415 ± 541 mm3 for LADs. The IBL prevalence was 67.6% in the LSSP group and 48.1% in the LAD group. LSSPs had 2.9-fold increased hazards of IBLs (95%CI: 1.2–7.4, p = 0.024), and LADs showed no significant correlation with IBLs. Size measurements had no impact on IBLs. A co-existing LSSP was associated with an increased prevalence of IBLs in patients with coronary artery disease (HR: 1.5, 95%CI: 1.1–1.9, p = 0.048), heart failure (HR: 3.7, 95%CI: 1.1–14.6, p = 0.032), arterial hypertension (HR: 1.9, 95%CI: 1.1–3.3, p = 0.017), and hyperlipidemia (HR: 2.2, 95%CI: 1.1–4.4, p = 0.018). ConclusionCo-existing LSSPs were associated with IBLs in patients with cardiovascular risk factors, however, pouch morphology did not correlate with the IBL rate. Upon confirmation by further studies, these findings might be considered in the treatment, risk stratification, and stroke prophylaxis of these patients.

Is there an association between left atrial outpouching structures and recurrence of atrial fibrillation after catheter ablation?

ObjectiveThe aim of this study was to investigate the impact of left atrial diverticula (LADs), left sided septal pouches (LSSPs) and middle right pulmonary veins (MRPVs) on recurrent atrial fibrillation (rAF) in patients undergoing laser pulmonary vein isolation procedure (PVI).Material and methodsThis retrospective study enrolled 139 patients with pre-procedural multiple detector computed tomography (MDCT) imaging and 12 months follow-up examination. LADs, LSSPs and MRPV were identified by two radiologists on a dedicated workstation using multiplanar reconstructions and volume rendering technique. Univariate and bivariate regression analyses with patient demographics and cardiovascular risk factors as covariates were performed to reveal independent factors associated with rAF.ResultsLADs were recorded in 41 patients (29%), LSSPs in 20 (14%) and MRPVs in 15 (11%). The right anterosuperior wall of the left atrium was the most prevalent location of LADs (68%). rAF occured in 20 patients, thereof, 15 exhibited an outpouching structure of the left atrium (LAD: 9, LSSP: 2 and MRPV: 3). Presence of an LAD (HR: 2.7, 95%CI: 1.0–8.4, p = 0.04) and permanent AF (HR: 4.8, 95%CI: 1.5–16.3, p = 0.01) were independently associated with rAF.ConclusionsLAD, LSSP and MRPV were common findings on pre-procedural cardiac computed tomography. LADs were revealed as potential independent risk factor of rAF, which might be considered for treatment planning and post-treatment observation.

Left atrial diverticula: Innocent bystanders or wolves in sheep's clothing?

The finding of left atria diverticula (LAD) on cardiac computed tomographyimages obtained from patients with atrial fibrillation (AF) referred for pulmonary vein isolation is not uncommon. Prior studies reporting on LAD do not always provide definitions of LAD resulting in confusion with other anatomical structures such as left atrial accessory appendages (LAAA) and atrial aneurysms. The aim of this review is to identify an accurate definition of LAD and to describe distinctive properties between LAD and other left atrial structures, such as LAAA and aneurysms. Also, the relation between LAD and development of atrial tachyarrhythmias is discussed. PubMed was searched for studies reporting on atrial aneurysms, left atrial diverticula, left atrial accessory appendages and atrial congenital aneurysms, resulting in 36 papers. LAD can be distinguished from LAAA by taking into account embryologic origins of the left atrium and their locations, resulting in the following definitions: (a) LAAA are contractile, trabeculated structures with circumscriptive ostia and narrow necks, originating from the primitive atria, (b) LAD are contractile, sac like structures with either smooth or trabeculated inner surfaces, circumscriptive ostia, narrow necks, and variable morphologies, originating from the embryologic common pulmonary vein, that incorporates into the LA, and (c) atrial aneurysms are non-contractile structures with wide necks and sac like bodies. There are no differences in prevalences of LAD between patients with sinus rhythm and AF. The pathophysiology of LAD is not yet fully understood. It is unlikely, that LAD are related to the development of atrial tachycardia's and AF by either being a source of ectopic activity or being part of an arrhythmogenic substrate. No differences in LAD prevalences between patients with sinus rhythm and AF have been found. Thus, it is unlikely that LAD could potentially be wolves in sheep's clothing.

Are left atrial diverticula and left-sided septal pouches relevant additional findings in cardiac CT? Correlation between left atrial outpouching structures and ischemic brain alterations

PurposeTo evaluate the correlation between left atrial diverticula (LAD) and left-sided septal pouches (LSSP) with ischemic brain alterations in MRI. MethodsA retrospective analysis of 174 patients who received both, a dedicated cardiac CT angiography (CCTA) and a brain MRI examination was performed. Two radiologists independently reviewed all examinations for the presence of LAD and LSSP as well as ischemic alterations of the brain. Subsequently, the correlation between these cardiac and cerebral findings as well as to other potentially related risk factors was assessed. Results71 LAD (total prevalence 41%) and 65 LSSP (total prevalence 37%) were identified in 174 patients. Combined prevalence was 10%. Ischemic brain alterations were found in patients with a LAD in 42.3% (30/71) and with a LSSP in 64.6% (42/65). Patients without any anatomical variant in the left atrium showed ischemic brain alterations in 39.4% (26/66). The presence of a LSSP was associated with an increased risk for ischemic brain alterations in multivariate logistic regression analysis after adjusting for other risk factors (OR = 3.57, 95% CI = 0.51–2.09, p < .01). ConclusionIn our study cohort LAD and LSSP are highly prevalent anatomical structures within the left atrium. Patients with LSSP showed an approximated 3.5-fold higher probability for ischemic brain alterations. Therefore, LSSP should be considered as a potential risk factor for cardioembolic strokes and its presence should be stated in cardiac CT reports.

Prevalence of left atrial diverticula and accessory appendages and origins of the sinoatrial nodal artery in patients with atrial fibrillation

Background: Considering the importance of knowledge about anatomical variations in the left atrium (LA) and its nearby structures for clinical decision-making and the lack of pertinent studies on Iranian patients, this study was conducted to determine the prevalence of LA diverticula and accessory appendages and the origins of the sinoatrial (SA) nodal artery in patients with atrial fibrillation. Methods: In this observational cross-sectional study, 45 consecutive patients with atrial fibrillation undergoing preprocedural computed tomography angiography were enrolled. The prevalence rates of LA diverticula and accessory appendages and the origins of the SA nodal artery were determined and compared according to the patients' age and gender. Results: The origin of the SA nodal artery was R1 (medial to right auricle) in 30 patients (66.7%), L1 (medial to left auricle) in 11 patients (24.4%), and both R1 and L1 in 1 patient. The origin in the remaining 3 subjects was L2 (posterior to auricle), L3 (posterior to left atrium), and R2 (posterior to right atrium). The prevalence rates of LA diverticula and accessory appendages were 48.9% and 17.8%, respectively. Diverticula were seen in 34.8% and 63.6% of the patients younger and older than 50 years, respectively (P = 0.050). Also, accessory appendages were present in 30.4% and 4.5% of the patients younger and older than 50 years, respectively (P = 0.047). There was no significant association for age (P > 0.05). Conclusions: The findings of the present study show that the main supplying artery of the SA nodal artery was R1 from the right coronary artery. The prevalence rates of LA diverticula and accessory appendages were higher than those reported previously.

OP-108 Impact of Left Atrial Diverticula on Outcome Following Cryoballoon-based Pulmonary Vein Isolation for Atrial Fibrillation

OP-108 Impact of Left Atrial Diverticula on Outcome Following Cryoballoon-based Pulmonary Vein Isolation for Atrial Fibrillation

Left Atrial Diverticula in Patients Undergoing Atrial Fibrillation Ablation: Morphologic Analysis and Clinical Impact

Left atrial diverticula (LAD) have been reported to be (1) at risk for intracavitary thrombosis and cardiac perforation during ablation and (2) sites of extrapulmonary vein foci. In atrial fibrillation (AF) ablation, their presence might undermine procedure safety and efficacy. This observational study evaluates the morphology and clinical impact of LAD in patients undergoing AF ablation. Consecutive patients undergoing computed tomography scan (Aquilion 64, Toshiba, Otawara, Japan) and AF ablation with imaging integration (CARTO 3 Merge, Biosense Webster, CA, USA) in our center were included. Morphologic analysis was performed by 2 independent radiologists. Ablation was obtained by irrigated radiofrequency energy (Navistar Thermocool or Thermocool SF, Biosense Webster). Out of 212 patients, 58 (27.3%) had LAD; 74.4% of LAD were located in the anterosuperomedial left atrium. In patients with and without LAD, the prevalence of prior cerebrovascular events was similarly low. The rate of major periprocedure complications did not differ significantly: 1.7% versus 2.6% (P = 1) in patients with and without LAD, respectively. However, 1 case of cardiac perforation occurred during ablation in a diverticulum. During follow-up, survival free from arrhythmia recurrences was comparable in the 2 groups. LAD are present in about one-fourth of patients undergoing AF ablation and, in general, they have no impact on its safety and efficacy. However, occasionally, radiofrequency energy delivery in a LAD can cause tissue overheating and perforation.

Left Atrial Diverticula in Patients Referred for Radiofrequency Ablation of Atrial Fibrillation

Background— The anatomic features of left atrial diverticula (LAD) are still unclear in patients with atrial fibrillation (AF). The purpose of this study was to evaluate the prevalence and morphological characteristics of LAD in patients referred for radiofrequency transcatheter ablation of AF with dual-source computed tomography. Methods and Results— Dual-source computed tomography images were obtained in 214 patients referred for AF catheter ablation and 214 sex- and age-matched control subjects. Images were analyzed to determine the prevalence and morphological characteristics of LAD and their relationship with adjacent pulmonary veins and left atrial appendage. In AF patients 77 (36.0%) (95% confidence interval, 29.6–42.4%) had 90 LAD, whereas in control subjects 70 (32.7%) (95% confidence interval, 26.4–39.0%) had 81 LAD ( P =0.551). In patients with AF, LAD locations were right anterosuperior (47.8%), left anterosuperior (8.9%), left lateral (32.2%), interatrial septum (4.4%), right inferior (5.6%), and posterosuperior (1.1%) walls, respectively. The mean size of LAD was 5.3±2.9×5.6±3.3 mm. The wall of the LAD was much thinner than that of adjacent left atrium (0.89±0.46 versus 2.39±0.83 mm). Most LAD were located close to a pulmonary vein or atrial appendage ostium, with a mean distance of 8.7–13.1 mm. Conclusions— LAD are common, with a prevalence of 36.0% in patients with AF, which is not statistically greater than that in patients without AF. Thin-walled LAD are more commonly located on the superior anterior wall of left atrium and close to common ablation sites.

Anatomical analysis of incidental left atrial diverticula in patients with suspected coronary artery disease using 64-channel multidetector CT

To describe and evaluate anatomical characterizations of incidental left atrial (LA) diverticula in patients with suspected coronary artery disease using 64-channel multidetector computed tomography (MDCT). From October 2008 to June 2009, 2059 patients with suspected coronary artery disease underwent electrocardiogram-gated 64-channel MDCT. Five hundred and thirty-two LA diverticula were identified in 377 patients (18.3%, male to female ratio: 216:161, mean age 59±10.89 years, range from 20 to 91 years). Two radiologists retrospectively analysed the number (single or multiple), size (diameter and length), shape (cystiform or tubiform), surface (smooth or irregular), and location (right or mid or left/upper or lower/lateral or posterior). If the length/diameter was <1.5, the diverticular shape was considered to be cystiform. Among 532 LA diverticula, single (270/532, 51.1%), cystiform (411/532, 77.3%), and smooth (332/532, 62.4%) diverticula were found. The right upper region (255/532, 47.9%) was the most common location, followed by the left lateral area (172/532, 32.3%). The average diameter was 4.7±2 mm (range from 1-19 mm), and the average length was 4.7±2.1 mm (range 1-13 mm). The average ratio of length to diameter was 1.15 (range 0.25-1.45). The average number of diverticula was 2±1.06 (range 1-5). Incidental LA diverticulum is not an uncommon finding in patients with suspected coronary artery disease. MDCT can provide anatomical details of LA diverticula. However, further studies are needed to determine their clinical significance.

Incidence and Characteristics of Left Atrial Diverticula in Patients Undergoing AF Ablation

Incidence and Characteristics of Left Atrial Diverticula in Patients Undergoing AF Ablation

Cardiac CT Assessment of Left Atrial Accessory Appendages and Diverticula

The purpose of this study is to describe the prevalence, morphology, size, and location of left atrial abnormalities including diverticula and accessory appendages in consecutive patients undergoing cardiac-gated CT for coronary artery evaluation. Routine retrospectively gated contrast-enhanced 64-MDCT angiography (0.75-mm collimation, 330-milliseconds gantry rotation time) was performed in 529 consecutive patients. CT data sets were evaluated using axial, sagittal, coronal, and interactive multiplanar reconstructions; maximum intensity projections (MIPs); and interactive volume rendering. The presence, type, and location of left atrial appendages and diverticula were recorded. One hundred twenty-one patients had left atrial accessory appendages (n = 20) or left atrial diverticula (n = 81) or both (n = 20). One hundred four left atrial diverticula were found in 101 of the 529 patients (20%) and 44 accessory appendages in 41 patients (8%). Of the atrial diverticula, 88% were superior and anterior, 9% were right lateral superior, and 3% were inferior. Of accessory appendages, 34% were inferior posterior, 32% were left inferior, 18% were superior anterior, 14% were inferior posterior, and 2% were right inferior posterior. The average sizes of diverticula were 6.4 +/- 2.5 x 6.2 +/- 2.4 mm, and accessory appendages were 4.9 +/- 2.1 x 3.9 +/- 2.4 mm. Left atrial diverticula and accessory appendages are commonly found on cardiac-gated CT.