Altered left atrial metrics in patients with cryptogenic stroke: A systematic review and meta-analysis

BACKGROUND

There is no defined cause for cryptogenic stroke/embolic stroke of undetermined source (CS-ESUS). As atrial fibrillation (AF) develops in a significant proportion of these patients, it has been suggested that left atrial (LA) myopathy may predispose to CS-ESUS. We investigated alterations in echocardiographic measures of LA size and function in patients with CS-ESUS.

METHODS

A systematic literature review and meta-analysis was performed. PubMed, EMBASE, Cochrane Library, Web of Science and SCOPUS were searched for articles published between 1 January 1990 and 10 February 2023. All observational studies of adult CS-ESUS patients with LA volume or function measurements performed by transthoracic echocardiogram were included. Individual random effects meta-analyses were performed on LA measurements in the CS-ESUS patients using subgroup analysis of comparator groups.

RESULTS

We included 29 articles with 3927 CS-ESUS patients. Analysis of weighted mean differences showed CS-ESUS patients had altered LA structure and function parameters, with a larger maximum indexed LA volume, reduced LA emptying fraction and/or LA reservoir strain, compared to healthy controls and noncardioembolic stroke patients. Conversely, CS-ESUS patients had a smaller left atrium with better function, compared to cardioembolic stroke patients and CS-ESUS patients who subsequently developed atrial fibrillation.

CONCLUSIONS

LA volume and function are altered in CS-ESUS patients compared to healthy controls and other stroke aetiologies. An underlying atrial myopathy in a subset of CS-ESUS patients may be involved in both thrombogenesis and dysrhythmia (specifically AF). While LA functional assessment is not currently recommended following stroke, it may offer an opportunity for recurrent stroke risk stratification.

The effect of body weight on left atrial function determined by longitudinal strain analysis in young adults

PURPOSE

Obesity is a risk factor for various cardiovascular disorders. Left atrial (LA) function is vital for predicting adverse outcomes in many diseases. LA strain was recently proposed as a noninvasive and valuable parameter for LA functional evaluation. We investigated the effect of body mass index (BMI) values on left atrial functions determined by longitudinal strain analysis in young adults without concomitant disease.

METHODS

We prospectively included 134 subjects in our study. Participants were categorized into three subgroups, obese, overweight, and control, according to their BMI. Conventional echocardiographic measurements and strain analysis were performed on all patients.

RESULTS

There were 41 patients (30.5%) in the obesity group, 46 patients (34.3%) in the overweight group, and 47 patients (35.0%) in the control group. Obese patients had significantly larger LA volume (46.9 ± 12.1 ml; p < 0.001) compared to overweight and control subjects; however, LA volume index (21.4 ± 6.1 ml/m2 vs. 22.4 ± 6.1 ml/m2 vs. 22.4 ± 5.0 ml/m2; p = 0.652) were similar between groups. In the LA strain analysis, obese patients were found to have lower left atrial reservoir longitudinal strain (LASr) compared to both the overweight and control group (44.2 ± 5.8% vs. 39.1 ± 3.7% vs. 36.5 ± 4.9%; p < 0.001); moreover obese patients had significantly worse left atrial contraction phase longitudinal strain (LASct) (-15.1 ± 3.1% vs. -13.1 ± 2.5%; p = 0.007) and left atrial conduit phase longitudinal strain (LAScd) (-29.0 ± 7.1% vs. -23.3 ± 5.4%; p < 0.001) values compared to the control group. However, LASct and LAScd values did not differ between overweight and obese patients.

CONCLUSION

LA function determined by LA strain analysis was impaired in obese and overweight individuals compared to the control group, even in the early stages of life. The prognostic significance of this finding should be investigated in prospective studies.

Left Atrial Strain Predicts Stroke Recurrence and Death in Patients With Cryptogenic Stroke

Left atrial strain (LAS) has been widely studied as a predictor of atrial fibrillation (AF) after cryptogenic stroke (CS). However, the evidence about its prognostic role in terms of stroke recurrence and death in this setting remains scarce. A total of 92 consecutive patients with ischemic stroke or transient ischemic attack with ABCD2 scale ≥4 of unknown etiology were prospectively recruited. Echocardiography, including LAS was performed during admission. The primary outcome measure was the composite of stroke recurrence or death. The mean age was 77.5 ± 7.7, and 58% of patients were female. After a median follow up of 28 months, the primary outcome measure occurred in 15 patients (16%). The primary outcome was more frequent in patients with diabetes (53% vs 21%, p = 0.02), chronic kidney disease (33% vs 10%, p = 0.034), and a history of heart failure (13% vs 0%, p = 0.025). LAS reservoir (LASr) and LAS conduit (LAScd) were lower in patients developing the primary outcome (21% ± 7% vs 28.8% ± 11%, p = 0.017 and 7.7% ± 3.9% vs 13.7% ± 7%, p = 0.007, respectively). On multivariate analysis, LASr (hazard ratio 0.9, 95% confidence interval 0.85 to 0.99, p = 0.048) and diabetes (hazard ratio 3.3, 95% confidence interval 1.03 to 10.4, p = 0.045) were associated with stroke recurrence or all-cause death after CS. On the log-rank test (using the discriminatory cut-off value of LASr <23%), LASr (p = 0.009) was associated with higher risk of the primary outcome. In conclusion, lower values of the LAS reservoir were associated with a higher risk of stroke recurrence or death after CS. LAS may identify patients at higher risk of thromboembolism and stress conditions.

The impact of image and performance enhancing drugs on atrial structure and function in resistance trained individuals

BACKGROUND

Image and performance enhancing drugs (IPEDs) are commonly used in resistance trained (RT) individuals and negatively impact left ventricular (LV) structure and function. Few studies have investigated the impact of IPEDs on atrial structure and function with no previous studies investigating bi-atrial strain. Additionally, the impact of current use vs. past use of IPEDs is unclear.

METHODS

Utilising a cross-sectional design, male (n = 81) and female (n = 15) RT individuals were grouped based on IPED user status: current (n = 57), past (n = 19) and non-users (n = 20). Participants completed IPED questionnaires, anthropometrical measurements, electrocardiography, and transthoracic echocardiography with strain imaging. Structural cardiac data was allometrically scaled to body surface area (BSA) according to laws of geometric similarity.

RESULTS

Body mass and BSA were greater in current users than past and non-users of IPEDs (p < 0.01). Absolute left atrial (LA) volume (60 ± 17 vs 46 ± 12, p = 0.001) and right atrial (RA) area (19 ± 4 vs 15 ± 3, p < 0.001) were greater in current users than non-users but this difference was lost following scaling (p > 0.05). Left atrial reservoir (p = 0.008, p < 0.001) and conduit (p < 0.001, p < 0.001) strain were lower in current users than past and non-users (conduit: current = 22 ± 6, past = 29 ± 9 and non-users = 31 ± 7 and reservoir: current = 33 ± 8, past = 39 ± 8, non-users = 42 ± 8). Right atrial reservoir (p = 0.015) and conduit (p = 0.007) strain were lower in current than non-users (conduit: current = 25 ± 8, non-users = 33 ± 10 and reservoir: current = 36 ± 10, non-users = 44 ± 13). Current users showed reduced LV diastolic function (A wave: p = 0.022, p = 0.049 and E/A ratio: p = 0.039, p < 0.001) and higher LA stiffness (p = 0.001, p < 0.001) than past and non-users (A wave: current = 0.54 ± 0.1, past = 0.46 ± 0.1, non-users = 0.47 ± 0.09 and E/A ratio: current = 1.5 ± 0.5, past = 1.8 ± 0.4, non-users = 1.9 ± 0.4, LA stiffness: current = 0.21 ± 0.7, past = 0.15 ± 0.04, non-users = 0.15 ± 0.07).

CONCLUSION

Resistance trained individuals using IPEDs have bi-atrial enlargement that normalises with allometric scaling, suggesting that increased size is, in part, associated with increased body size. The lower LA and RA reservoir and conduit strain and greater absolute bi-atrial structural parameters in current than non-users of IPEDs suggests pathological adaptation with IPED use, although the similarity in these parameters between past and non-users suggests reversibility of pathological changes with withdrawal.

Atrial strain and occult atrial fibrillation in cryptogenic stroke patients: a systematic review and meta-analysis

BACKGROUND

Cryptogenic stroke (CS) remains a significant cause of morbidity. Failure to identify the underlying pathology increases the rate of recurrence. Atrial fibrillation (AF) seems to be responsible for a substantial proportion of CS. Thus, there is an unmet need to identify and properly treat those with silent AF.

PURPOSE

To investigate the association between left atrial strain and newly diagnosed AF in CS patients.

OBJECTIVES

We searched major electronic databases for articles assessing the relationship between either peak left atrial longitudinal (PALS) or peak contractile (PACS) strain-quantified using speckle tracking echocardiography-and the incidence of occult AF during the diagnostic work-up of CS patients.

RESULTS

Eleven studies (two thousand and eighty-one patients) were analyzed. Incidence of occult AF was 19%. Both PALS and PACS were significantly lower in patients with newly diagnosed AF (MD - 8.6%, 95%CI - 10.7 to - 6.4, I2 86.4% and MD - 5.5, 95%CI - 6.8 to - 4.2, I2 80.8%). According to the diagnostic accuracy meta-analysis, PALS < 20% present 71% (95%CI 47-87%) sensitivity and 71% (95%CI 60-81%) specificity for the diagnosis of occult AF, assuming a prevalence of 20%. The corresponding values for PACS < 11% are 83% (95%CI 57-94%) and 78% (95%CI 56-91%).

CONCLUSION

Both PALS and PACS are significantly lower in patients with CS and silent AF. It seems that the cut-off values mentioned above could help physicians in identifying patients who may benefit more from prolonged rhythm monitoring. More studies are needed to confirm these findings.

Echocardiographic Evaluation of Atrial Remodelling for the Prognosis of Maintaining Sinus Rhythm after Electrical Cardioversion in Patients with Atrial Fibrillation

Atrial fibrillation (AF) is the most common atrial tachyarrhythmia. One of the methods of AF treatment is direct current cardioversion (DCCV), but in the long-term follow-up we observe quite a high percentage of AF recurrences after this procedure. In order to assess the prognosis of DCCV effectiveness, we use clinical, biochemical and echocardiographic parameters. The objective of this review is to systematise the current knowledge on echocardiographic measurements in patients with persistent AF used to assess the progress of remodelling of the atrial wall, which affects the likelihood of maintaining sinus rhythm after DCCV. In this article, echocardiographic parameters for the evaluation of remodelling of the atrial wall are divided into groups referring to structural, mechanical, and electrical remodelling, as well as parameters for the evaluation of left ventricular filling pressure. The article aims to draw attention to the clinical value of echocardiographic measurements, which is the selection of patients who will maintain sinus rhythm after DCCV in the long-term follow-up, which will allow to avoid unnecessary risks associated with the procedure and enable the selection of the appropriate treatment strategy.

Left atrial appendage strain predicts subclinical atrial fibrillation in embolic strokes of undetermined source

Aims

Left atrial (LA) strain is promising in prediction of clinical atrial fibrillation (AF) in stroke patients. However, prediction of subclinical AF is critical in patients with embolic strokes of undetermined source (ESUS). The aim of this prospective study was to investigate novel LA and left atrial appendage (LAA) strain markers in prediction of subclinical AF in ESUS patients.

Methods and results

A total of 185 patients with ESUS, mean age 68 ± 13years, 33% female, without diagnosed AF, were included. LAA and LA function by conventional echocardiographic parameters and reservoir strain (Sr), conduit strain (Scd), contraction strain (Sct), and mechanical dispersion (MD) of Sr were assessed with transoesophageal and transthoracic echocardiography. Subclinical AF was detected by insertable cardiac monitors during follow-up. LAA strain was impaired in 60 (32%) patients with subclinical AF compared to those with sinus rhythm: LAA-Sr, 19.2 ± 4.5% vs. 25.6 ± 6.5% (P < 0.001); LAA-Scd, -11.0 ± 3.1% vs. -14.4 ± 4.5% (P < 0.001); and LAA-Sct, -7.9 ± 4.0% vs. -11.2 ± 4% (P < 0.001), respectively, while LAA-MD was increased, 34 ± 24 ms vs. 26 ± 20 ms (P = 0.02). However, there was no significant difference in phasic LA strain or LA-MD. By ROC analyses, LAA-Sr was highly significant in prediction of subclinical AF and showed the best AUC of 0.80 (95% CI 0.73-0.87) with a sensitivity of 80% and a specificity of 73% (P < 0.001). LAA-Sr and LAA-MD were both independent and incremental markers of subclinical AF in ESUS patients.

Conclusion

LAA function by strain and mechanical dispersion predicted subclinical AF in ESUS patients. These novel echocardiographic markers may improve risk stratification in ESUS patients.

Prognostic significance of left atrial strain in sarcomere gene variant carriers without hypertrophic cardiomyopathy

Background

Genetic testing of relatives of hypertrophic cardiomyopathy (HCM) patients has led to a large group of genotype‐positive, phenotype‐negative (G+/Ph−) subjects. Prediction of progression to overt HCM in these subjects is challenging. While left atrial (LA) strain is reduced in HCM patients it is currently unknown whether this parameter can be used to predict HCM phenotype progression.

Methods

This study includes 91 G+/Ph− subjects and 115 controls. Standard echocardiographic parameters as well as left ventricular global longitudinal strain (LV GLS) and LA reservoir strain (LASr) were assessed for each patient. Logistic and Cox proportional hazard regression analyses were used to investigate predictors of G+/Ph− status and HCM during follow‐up.

Results

Independent predictors of G+ status included pathological Q waves (OR 1.60 [1.15–2.23], p < .01), maximal wall thickness (MWT: OR 1.10 [1.07–1.14], p < .001), mitral inflow E wave (OR 1.06 [1.02–1.10, p = .001), A wave (OR 1.06 [1.03–1.10], p < .001), LV GLS (OR .96 [.94–.98], p < .001), and LASr (OR .99 [.97–.99], p = .03). In univariable Cox regression analysis, male sex (HR 2.78 [1.06–7.29], p = .04), MWT (HR 1.72 [1.14–2.57], p = .009) and posterior wall thickness (HR 1.65 [1.17–2.30], p = .004) predicted HCM during a median follow‐up of 5.9 [3.2–8.6] years, whereas LASr did not (HR .95 [.89–1.02], p = .14). There were no significant predictors of HCM after multivariable adjustment.

Conclusion

LASr is significantly impaired in G+/Ph− subjects and is an independent predictor of G+/Ph− status, but did not predict HCM development during follow‐up.

Utility of speckle-tracking echocardiography for predicting atrial fibrillation following ischemic stroke: a systematic review and meta-analysis

Undiagnosed atrial fibrillation (AF) is one of the main sources of cryptogenic stroke. And strain indices measured by speckle-tracking echocardiography are associated with atrial remodeling supposed to be the substrate of AF. Therefore, there is a strong need for evaluating the utility of speckle-tracking echocardiography to predict the likelihood of AF in patients with cryptogenic stroke. PubMed, Embase and Cochrane Database were searched for studies. The random-effects model was used to calculate the pooled results, and summary receiver operating characteristic curve (SROC) analysis was performed to show the overall predictive value. There were 1483 patients with cryptogenic stroke from 8 studies. Meta-analysis showed that strain indices including global longitudinal strain (GLS) (mean difference [SMD]: - 0.22, 95% confidence interval [95% CI] - 0.40 to - 0.04), left atrial reservoir strain (εR), (SMD: - 0.87, 95% CI - 1.26 to - 0.48, conduit strain (εCD) (SMD: - 0.56, 95% CI - 0.81 to - 0.30), contractile strain (εCT) (SMD: - 1.00, 95% CI - 1.39 to - 0.61), and left atrial reservoir strain rate (SRe) (SMD: - 0.54, 95% CI - 0.80 to - 0.28) measured at the period of cryptogenic stroke was significantly decreased in patients with AF occurrence compared to without. SROC analysis suggested an acceptable predictive efficiency of εR for AF occurrence (AUC = 0.799). For patients after cryptogenic stroke, GLS, εR, εCD, εCT and SRe were significantly decreased in AF occurrence compared with non-occurrence. But there was no value in left atrial reservoir strain rate (SRs) and contractile strain rate (SRa) for predicting AF.

Diagnostic And Prognostic Value Of Left Atrial Function In Identification Of Cardioembolism And Prediction Of Outcomes In Patients With Cryptogenic Stroke

BACKGROUND

Strokes of undetermined source, commonly termed cryptogenic stroke (CS), account for a significant proportion of ischemic stroke etiology and have high rates of stroke recurrence. The heterogeneous etiology of CS makes decisions regarding treatment for such patients challenging. We sought to evaluate the diagnostic and prognostic value of left atrial (LA) function in identification of cardioembolism and prediction of outcomes in patients with CS.

METHODS

Consecutive patients admitted to our tertiary institution with ischemic stroke or transient ischemic attack (TIA) who underwent transthoracic echocardiography were recruited with comprehensive evaluation of LA metrics including LA strain. Ischemic strokes / TIAs were classified as non-cardioembolic, cryptogenic and cardioembolic. A total of 709 patients (66.0±15.1 years, 55% male) were recruited. 291 patients had CS, 189 had non-cardioembolic stroke and 229 had cardioembolic stroke. Patients with CS were followed for 20.0±13.8 months for recurrent ischemic stroke / TIA.

RESULTS

Receiver-operating characteristic curves showed LA reservoir (LASr) and contractile (LASct) strains to be strong discriminators of cardioembolic strokes and log rank tests showed both measures to be significantly associated with the distribution of time to recurrent ischemic stroke / TIA in patients with CS. Multivariable hazards models showed LASr and LASct to be independent predictors of recurrent ischemic stroke / TIA in CS patients in addition to eGFR and active smoking.

CONCLUSIONS

LASr and LASct were strong discriminators of cardioembolic stroke and independently predicted recurrent ischemic stroke / TIA in patients with CS. Use of LA strain may improve risk stratification and decision-making in patients with CS, with particular regards to prolonged ambulatory heart rhythm monitoring and/or empiric anticoagulation.

ESC Working Group on e-Cardiology Position Paper: accuracy and reliability of electrocardiogram monitoring in the detection of atrial fibrillation in cryptogenic stroke patients : In collaboration with the Council on Stroke, the European Heart Rhythm Association, and the Digital Health Committee

The role of subclinical atrial fibrillation as a cause of cryptogenic stroke is unambiguously established. Long-term electrocardiogram (ECG) monitoring remains the sole method for determining its presence following a negative initial workup. This position paper of the European Society of Cardiology Working Group on e-Cardiology first presents the definition, epidemiology, and clinical impact of cryptogenic ischaemic stroke, as well as its aetiopathogenic association with occult atrial fibrillation. Then, classification methods for ischaemic stroke will be discussed, along with their value in providing meaningful guidance for further diagnostic efforts, given disappointing findings of studies based on the embolic stroke of unknown significance construct. Patient selection criteria for long-term ECG monitoring, crucial for determining pre-test probability of subclinical atrial fibrillation, will also be discussed. Subsequently, the two major classes of long-term ECG monitoring tools (non-invasive and invasive) will be presented, with a discussion of each method's pitfalls and related algorithms to improve diagnostic yield and accuracy. Although novel mobile health (mHealth) devices, including smartphones and smartwatches, have dramatically increased atrial fibrillation detection post ischaemic stroke, the latest evidence appears to favour implantable cardiac monitors as the modality of choice; however, the answer to whether they should constitute the initial diagnostic choice for all cryptogenic stroke patients remains elusive. Finally, institutional and organizational issues, such as reimbursement, responsibility for patient management, data ownership, and handling will be briefly touched upon, despite the fact that guidance remains scarce and widespread clinical application and experience are the most likely sources for definite answers.

Prevalence of markers of atrial cardiomyopathy in embolic stroke of undetermined source: A systematic review

BACKGROUND

Emerging evidence suggests the potential role of atrial cardiomyopathy (AC) as a direct thromboembolic determinant in embolic stroke of undetermined source (ESUS).

OBJECTIVE

We aimed to quantify the prevalence of potential AC markers among ESUS, non-cardioembolic (NCE) and cardioembolic (CE) stroke patients.

METHODS

PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched for publications from inception to October 2021, with duplicate data extraction and risk of bias assessment. The Newcastle-Ottawa assessment scale was used to evaluate study quality.

RESULTS

Among 398 screened studies, 11 observational studies with 2009 ESUS patients (mean age 66.5 years) fulfilled the inclusion criteria. Of electrocardiographic markers, increased P-wave terminal force in lead V1 was more prevalent in ESUS vs NCE (OR=2.26, 95%CI: 1.40-3.66). Of imaging markers, left atrial volume index (LAVI) and left atrial diameter (LAd) were higher in ESUS vs NCE (OR=1.04, 95%CI: 1.02-1.06 and OR=3.41, 95%CI: 1.35-8.61 respectively). Non-chicken wing morphology of the left atrial appendage was more frequent in ESUS compared to NCE patients in the majority of studies. Of serum biomarkers, the prevalence of NT-proBNP >250 pg/ml did not differ among ESUS vs NCE (OR=0.73, 95%CI: 0.39 -1.35).

CONCLUSIONS

Electrocardiographic, echocardiographic markers and advanced imaging modalities able to assess the morphologic characteristics of left atrial appendage and left atrial function may be important tools to discriminate AC among ESUS vs NCE stroke patients. Prospective studies exploring the association of potential AC markers with ESUS occurrence are warranted to validate their clinical utility.

Transesophageal Echocardiography in Ischemic Stroke With Atrial Fibrillation

Background

To clarify differences in clinical significance of intracardiac thrombi in nonvalvular atrial fibrillation‐associated stroke as identified by transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE).

Methods and Results

Using patient data on nonvalvular atrial fibrillation‐associated ischemic stroke between 2011 and 2014 from 15 South Korean stroke centers (n=4841) and 18 Japanese centers (n=1192), implementation rates of TEE/TTE, and detection rates of intracardiac thrombi at each center were correlated. The primary outcome was recurrent ischemic stroke at 1 year after the onset. A total of 5648 patients (median age, 75 years; 2650 women) were analyzed. Intracardiac thrombi were detected in 75 patients (1.3%) overall. Thrombi were detected in 7.8% of patients with TEE (either TEE alone or TEE+TTE: n=679) and in 0.6% of those with TTE alone (n=3572). Thrombus detection rates varied between 0% and 14.3% among centers. As TEE implementation rates at each center increased from 0% to 56.7%, thrombus detection rates increased linearly (detection rate [%]=0.11×TEE rate [%]+1.09 [linear regression], P<0.01). TTE implementation rates (32.3%–100%) were not associated with thrombus detection rates (P=0.53). Intracardiac thrombi were associated with risk of recurrent ischemic stroke overall (adjusted hazard ratio [aHR] 2.35, 95% CI, 1.07–5.16). Thrombus‐associated ischemic stroke risk was high in patients with TEE (aHR, 3.13; 95% CI, 1.17–8.35), but not in those with TTE alone (aHR, 0.89; 95% CI, 0.12–6.51).

Conclusions

Our data suggest clinical relevance of TEE for accurate detection and risk stratification of intracardiac thrombi in nonvalvular atrial fibrillation‐associated stroke.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01581502.

Post-ablation left atrial function impacts long-term recurrence of atrial fibrillation after ablation

Left atrial (LA) function can help predict various cardiovascular events. Catheter ablation for atrial fibrillation (AF) modifies baseline LA function through the maintenance of sinus rhythm and myocardial injury. We investigated the impact of post-ablation LA function on recurrence of AF after ablation and identified the predictors of reduced post-ablation LA function. A total of 616 patients who underwent AF ablation (paroxysmal, N = 310; non-paroxysmal, N = 306) were retrospectively examined with cardiac computed tomography at baseline and 3 months after the final ablation procedure. Post-ablation LA emptying fraction (LAEF_post) was calculated. We evaluated the association between LAEF_post and recurrence of AF after the final ablation procedure. Further, we assessed the predictors of reduced LAEF_post. The recurrence rate of AF was 72.7% after the final ablation procedure [median follow-up 48 months (48.0, 48.0), total number of ablation sessions: 1.4 ± 0.7]. Multivariate analysis revealed that LAEF_post was associated with the recurrence of AF (hazard ratio/10% increase: 0.62, 95% confidence interval: 0.51-0.75, P < 0.0001). LAEF_post had a mild predictive power for recurrence of AF (c-statistics: 0.670, optimal cutoff: 26.36%, P < 0.0001). The recurrence-free proportion among patients with reduced LAEF_post (< 26.36%, N = 100) and those with preserved LAEF_post (≥ 26.36%, N = 516) was 40% and 79%, respectively (P < 0.0001). The predictors of reduced LAEF_post were low pre-ablation LAEF, high pre-ablation LA volume, low body mass index (BMI), and female sex. Further, reduced LAEF_post was associated with the total number of ablation sessions and extra-pulmonary vein LA ablation. In conclusion, reduced LAEF_post was associated with recurrence of AF after ablation. Advanced LA remodeling, low BMI, and female sex could predict reduced LAEF_post. Although additional ablation was associated with reduced LAEF_post, it remains unclear whether reduced LAEF_post resulted from the additional ablation. Reduced LAEF_post might help stratify patients with ablation-refractory AF.

Left atrial contractile longitudinal strain determines intrinsic left atrial function regardless of load status and left ventricular deformation

PURPOSE

Left atrial (LA) longitudinal strain (S) has been proposed as a superior, non-invasive parameter over LA volumetric assessment. LAS has diagnostic and prognostic value in many cardiovascular pathologies. Nevertheless, the acute effect of hemodynamic changes on LAS indices is not well-established. We sought to identify volume independent physiomechanical changes in LA and interrelation between LA and left ventricular (LV) strain indices following a large amount of fluid loss provided by hemodialysis.

METHODS

Seventy-five patients between 18 and 85 years of age under hemodialysis therapy were included. The echocardiographic images were obtained before and after hemodialysis. Phasic LAS and LV global longitudinal strain (GLS) were calculated. The impact of volume depletion on echocardiographic measurements and their temporal correlation were calculated.

RESULTS

LV and LA dimensions,volumes and LV, LA reservoir, and conduit deformation showed a significant decrease after hemodialysis. No significant change was observed for LAS_contraction (p = 0.203). The ultrafiltrated volume was significantly correlated with the changes in LVGLS (r = 0.75, p < 0.001), and LAS_reservoir (r = 0.81, p < 0.001) and LA total emptying volume (r = 0.80, p < 0.001). Absolute changes in LAS_reservoir and LVGLS were strongly correlated (r = 0.83, p < 0.001). There was no correlation between absolute changes in LAS_contraction and LVGLS or ultrafiltrated volume (p = NS, both).

CONCLUSION

LA reservoir and conduit LS are highly volume dependent strain parameters and are strongly correlated with LV deformation along with ultrafiltrated volume. Acute excessive volume depletion or LV deformation have no influence on LAS_contraction. It is important to identify independent easily accessible functional parameters for the LA which would improve clinical evaluation.

Predictive value of left atrial function for latent paroxysmal atrial fibrillation as the cause of embolic stroke of undetermined source

BACKGROUND

In patients with embolic stroke of undetermined source (ESUS), paroxysmal atrial fibrillation (AF) is often diagnosed, however, the risk of paroxysmal AF in ESUS has not been well described. Several studies have suggested a linkage between left atrial (LA) functional parameters and risk of AF in stroke patients. The aim of this study was to assess the role of LA functional parameters as predictors of latent paroxysmal AF in ESUS on admission.

METHODS

Between January 2015 and December 2019, consecutive stroke patients with suspected ESUS at admission were prospectively included in this study. They were under hospital electrocardiographic monitoring for detection of new-onset AF. Various echocardiographic parameters including left atrial strain were assessed for association with new-onset AF.

RESULTS

We gathered 1082 consecutive patients with ischemic stroke. After exclusions, 121 patients with suspected ESUS at admission formed the study cohort. New-onset AF was detected in 46 (38%) patients during hospital electrocardiographic monitoring (median follow-up: 18 days). LA pump and reservoir strains were significantly and independently associated with new-onset AF. Receiver operating characteristic analysis for the association with new-onset AF showed that the areas under the curve (AUCs) of clinical parameters plus one of each strain (LA pump strain: AUC: 0.86±0.04 and LA reservoir strain: AUC: 0.76±0.05) models were significantly better than plus LA volume index (AUC: 0.68±0.04, compared p-values <0.05).

CONCLUSIONS

LA strain was significantly associated with new development of AF. Patients with impaired LA function at admission should be carefully monitored to find AF.

Echocardiographic Measurement of Left Atrial Strain - A Key Requirement in Clinical Practice

Unlike the left ventricle (LV), the left atrium (LA) has a thin-walled structure and has been regarded as a simple conduit chamber. However, the unique function of the LA to modulate LV filling has recently drawn much attention. Because LA structure and function are directly influenced by the LV filling pressure, LA assessment is an essential step in the diagnosis of diastolic dysfunction that can help predict new-onset atrial fibrillation, assess the risk of further embolic events, and identify high-risk patients for adverse cardiovascular events. Even in the recent era of multimodality imaging, 2-dimensional (2D) echocardiography is the most common imaging method and the central modality for evaluation of LA function. LA strain derived from 2D echocardiography can help assess LA function objectively and demonstrates the 3 distinct phasic motions of the LA cycle. Further, LA strain provides invaluable pathophysiologic information and helps to predict clinical prognosis in various cardiovascular diseases. In this review article, we focus on LA strain: basic concepts, advantages over conventional parameters, and some unresolved issues. Additionally, we present a brief history of the clinical evidence for LA strain. Through this review, we suggest echocardiography for LA strain assessment in clinical practice.

Imaging Techniques for the Study of Fibrosis in Atrial Fibrillation Ablation: From Molecular Mechanisms to Therapeutical Perspectives

Atrial fibrillation (AF) is the most prevalent form of cardiac arrhythmia. It is often related to diverse pathological conditions affecting the atria and leading to remodeling processes including collagen accumulation, fatty infiltration, and amyloid deposition. All these events generate atrial fibrosis, which contribute to beget AF. In this scenario, cardiac imaging appears as a promising noninvasive tool for monitoring the presence and degree of LA fibrosis and remodeling. The aim of this review is to comprehensively examine the bench mechanisms of atrial fibrosis moving, then to describe the principal imaging techniques that characterize it, such as cardiac magnetic resonance (CMR) and multidetector cardiac computed tomography (MDCT), in order to tailor atrial fibrillation ablation to each individual.