Echocardiography predictors of sustained sinus rhythm after cardioversion of supraventricular arrhythmia in patients with septic shock.

PURPOSE: The echocardiography parameters may predict the maintenance of sinus rhythm after cardioversion of a supraventricular arrhythmia (SVA). MATERIALS AND METHODS: Patients in septic shock with onset of an SVA, normal to moderately reduced LV systolic function (EF_LV˃̳35%) and on a continuous noradrenaline of <1.0 µg/kg.min were included. Echocardiography was performed at the arrhythmia onset, 1 h and 4 h post cardioversion on an infusion of propafenone or amiodarone. RESULTS: Cardioversion was achieved in 96% of the 209 patients within a median time of 6(1.8-15.6)h, 134(64.1%) patients experienced at least one SVA recurrence after cardioversion. At 4 h the left atrial emptying fraction (LA_EF, cut-off 38.4%, AUC 0.69,p˂0.001), and transmitral A wave velocity-time-integral (Avti, cut-off 6.8 cm, AUC 0.65,p = 0.001) showed as limited predictors of a single arrhythmia recurrence. The LA_EF 44(36,49)%, (p = 0.005) and the Avti 8.65(7.13,9.50)cm, (p < 0.001) were associated with sustained sinus rhythm and decreased proportionally to increasing numbers of arrhythmia recurrences (p < 0.001 and p = 0.007, respectively). The enlarged left atrial end-systolic diameter at the arrhythmia onset (p = 0.04) and elevated systolic pulmonary artery pressure at 4 h (p = 0.007) were weak predictors of multiple(˃3) recurrences. CONCLUSION: The LA_EF and Avti are related to arrhythmia recurrences post-cardioversion suggesting potential guidance to the choice between rhythm and rate control strategies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03029169, registered on 24th of January 2017.

Echocardiographic Parameters of Left Atrial Structure and Function and Clinical Outcomes at 2 Years in Elderly Patients With Atrial Fibrillation　- The ANAFIE Echocardiographic Substudy.

BACKGROUND: This prospective ANAFIE Registry substudy investigated the relationship between the echocardiographic parameters of left atrial (LA) structure and function and clinical outcomes at 2 years among atrial fibrillation (AF) patients aged ≥75 years.Methods and Results: Outcomes of 1,474 elderly non-valvular AF (NVAF) patients who underwent transthoracic echocardiography at baseline were analyzed by categories of maximum LA volume index (max. LAVi) and LA emptying fraction (LAEF) total. Baseline mean±standard deviation LAEF total and max. LAVi were 28.2±14.9% and 54.2±25.9 mL/m2, respectively. Proportions of oral anticoagulant (OAC), direct OAC, and warfarin use were 92.7%, 68.7%, and 24.0%, respectively. Patients with LAEF total ≤45.0% (n=1,213) vs. >45.0% (n=224) were at higher risk of cardiovascular events (hazard ratio [HR]: 2.19, P=0.021) and heart failure (HF) hospitalization (HR: 2.25, P=0.045). Risk of all-cause death was higher with max. LAVi >48.0 mL/m2(n=656) vs. ≤48.0 mL/m2(n=621) (HR: 1.69, P=0.048). Subgroups with abnormal LA function and structure had increased incidence of cardiac/cardiovascular events and HF hospitalization. No significant interaction was observed between echocardiographic parameters and OAC type. CONCLUSIONS: Elderly Japanese patients with NVAF and LAEF total ≤45.0% were at higher risk of cardiovascular events and HF hospitalization, and those with max. LAVi >48.0 mL/m2were at higher risk of all-cause death.

The use of dedicated long-axis views focused on the left atrium improves the accuracy of left atrial volumes and emptying fraction measured by cardiovascular magnetic resonance.

BACKGROUND: The use of apical views focused on the left atrium (LA) has improved the accuracy of LA volume evaluation by two-dimensional (2D) echocardiography. However, routine cardiovascular magnetic resonance (CMR) evaluation of LA volumes still uses standard 2- and 4-chamber cine images focused on the left ventricle (LV). To investigate the potential of LA-focused CMR cine images, we compared LA maximuml (LAVmax) and minimum (LAVmin) volumes, and emptying fraction (LAEF), calculated on both standard and LA-focused long-axis cine images, with LA volumes and LAEF obtained by short-axis cine stacks covering the LA. LA strain was also calculated and compared between standard and LA-focused images. METHODS: LA volumes and LAEF were obtained from 108 consecutive patients by applying the biplane area-length algorithm to both standard and LA-focused 2- and 4-chamber cine images. Manual segmentation of a short-axis cine stack covering the LA was used as the reference method. In addition, LA strain reservoir (εs), conduit (εe) and booster pump (εa) were calculated using CMR feature-tracking. RESULTS: Compared to the reference method, the standard approach significantly underestimated LA volumes (LAVmax: bias - 13 ml; LOA = + 11, - 37 ml; LAVmax i: bias - 7 ml/m2; LOA = + 7, - 21 ml/m2; LAVmin; bias - 10 ml, LOA: + 9, - 28 ml; LAVmin i: bias - 5 ml/m2, LOA: + 5, - 16 ml/m2), and overestimated LA-EF (bias 5%, LOA: + 23, - 14%). Conversely, LA volumes (LAVmax: bias 0 ml; LOA: + 10, - 10 ml; LAVmax i: bias 0 ml/m2; LOA: + 5, - 6 ml/m2; LAVmin: bias - 2 ml; LOA: + 7, - 10 ml; LAVmin i: bias - 1 ml/m2; LOA: + 3, - 5 ml/m2) and LAEF (bias 2%, LOA: + 11, - 7%) by LA-focused cine images were similar to those measured using the reference method. LA volumes by LA-focused images were obtained faster than using the reference method (1.2 vs 4.5 min, p < 0.001). LA strain (εs: bias 7%, LOA = 25, - 11%; εe: bias 4%, LOA = 15, - 8%; εa: bias 3%, LOA = 14, - 8%) was significantly higher in standard vs. LA-focused images (p < 0.001). CONCLUSION: LA volumes and LAEF measured using dedicated LA-focused long-axis cine images are more accurate than using standard LV-focused cine images. Moreover, LA strain is significantly lower in LA-focused vs. standard images.

Quantification of left atrial function by the area-length method overestimates left atrial emptying fraction.

PURPOSE: The biplane area-length method is commonly used in cardiac magnetic resonance (CMR) to assess left atrial (LA) volume (LAV) and function. Associations between left atrial emptying fraction (LAEF) and clinical outcomes have been reported. However, only limited data are available on the calculation of LAEF using the biplane method compared to 3D assessment. This study aimed to compare volumetric and functional LA parameters obtained from the biplane method with 3D assessment in a large, multiethnic cohort. METHOD: 158 participants of MESA (Multi-Ethnic Study of Atherosclerosis) underwent CMR that included standard two- and four-chamber steady-state free precession (SSFP) cine imaging for the biplane method. For 3D-based assessment, short-axis SSFP cine series covering the entire LA were obtained, followed by manual delineation of LA contours to create a time-resolved 3D LAV dataset. Paired t-tests and Bland-Altman plots were used to analyze the data. RESULTS: Standard volumetric assessment showed that LAVmin (bias: -8.35 mL, p < 0.001), LAVmax (bias: -9.38 mL, p < 0.001) and LAVpreA (bias: -10.27 mL, p < 0.001) were significantly smaller using the biplane method compared to 3D assessment. Additionally, the biplane method reported significantly higher LAEFtotal (bias: 7.22 %, p < 0.001), LAEFactive (bias: 6.08 %, p < 0.001), and LAEFpassive (bias: 4.51 %, p < 0.001) with wide limits of agreement. CONCLUSIONS: LA volumes were underestimated using the biplane method compared to 3D assessment, while LAEF parameters were overestimated. These findings demonstrate a lack of precision using the biplane method for LAEF assessment. Our results support the usage of 3D assessment in specific settings when LA volumetric and functional parameters are in focus.

A systematic review and meta-analysis of the impact of the left atrial appendage closure on left atrial function.

BACKGROUND: Left atrial (LA) appendage closure (LAAC) is effective in patients with atrial fibrillation who are not candidates for long-term anticoagulation. However, the impact of LAAC on LA function is unknown. The aim of this study is to evaluate the impact of LAAC on atrial function. METHODS: This meta-analysis was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A search strategy was designed to utilize PubMed/Medline, EMBASE, and Google scholar for studies showing the effect of LAAC on the LA function from inception to November 20, 2021. The standardized mean difference (SMD) was calculated from the means and standard deviations. RESULTS: Of 247 studies initially identified, 8 studies comprising 260 patients were included in the final analysis. There was a significant increase in LA emptying fraction following LAAC compared with preoperative function (SMD: 0.53; 95% confidence interval [CI]: 0.04-1.01; p = .03; I2 = 75%). In contrast, there were no significant differences in LA volume (SMD: -0.07; 95% CI: -0.82-0.69; p = .86; I2 = 92%) peak atrial longitudinal strain (SMD: 0.50; 95% CI: -0.08-1.08; p = .09; I2 = 89%), peak atrial contraction strain (SMD: 0.38; 95% CI: -0.22-0.99; p = .21; I2 = 81%), strain during atrial contraction (SMD: -0.24; 95% CI: -0.61-0.13; p = .20; I2 = 0%), strain during ventricular systole (SMD: 0.47; 95% CI: -0.32-1.27; p = .24; I2 = 89%), strain during ventricular diastole (SMD: 0.09; 95% CI: -0.32-0.51; p = .66; I2 = 65%). CONCLUSION: LAAC is associated with improvement in the left atrial emptying fraction, but did not significantly influence other parameters.

Quantification of Right Atrial-Indexed End-Systolic Volumes and Emptying Fraction in Children Undergoing Cardiac Surgery With Two-Dimensional Transesophageal Echocardiography: A Prospective Observational Study.

OBJECTIVES: The primary objective of this study was to establish "normal" right atrial (RA)-indexed end-systolic volumes (ESVs) and emptying fraction (EF) in children undergoing ventricular septal defect (VSD) repair using two-dimensional (2D) transesophageal echocardiography (TEE). Secondary objectives were to obtain RA-indexed ESV and EF in children with RA/right ventricular (RV) volume overload (atrial septal defect [ASD]) and RV pressure overload (tetralogy of Fallot [TOF]) and to determine whether baseline differences existed in these indices among the three lesions. DESIGN: A prospective observational study. SETTING: Tertiary referral center and a university level teaching hospital. PARTICIPANTS: The study comprised 90 children (30 in each cohort) >3 kg and <14 years old admitted for elective repair of either VSD, TOF, or ASD. MEASUREMENTS AND MAIN RESULTS: RA ESV and EF were measured in the midesophageal four-chamber view using the area-length and the modified Simpson's methods with 2D TEE in the prebypass period. Mean RA- indexed ESV (area-length method) in the VSD cohort was 24.2 ± 6.7 mL/m2, whereas it was significantly greater in the TOF (31.9 ± 9.8 mL/m2; p = 0.0008) and ASD (52 ± 12.9 mL/m2; p < 0.0001) cohorts. RA EF in the TOF cohort was 48.4% ± 7.6%, which was significantly more than in the VSD (41.5% ± 11.8%; p = 0.0093) and ASD (39.1% ± 12.3%; p = 0.0008) cohorts. CONCLUSIONS: This was the first study using 2D TEE to measure RA indices in children with and without right-sided heart dilation undergoing cardiac surgery. In this study, RA, ESV, and EF were considerably different in children with congenital heart disease causing RV pressure or volume overload. Additional studies can examine how these values can be used for risk stratification in this cohort of patients or how they correlate with measures of ventricular performances.

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 (LAEFpost) was calculated. We evaluated the association between LAEFpost and recurrence of AF after the final ablation procedure. Further, we assessed the predictors of reduced LAEFpost. 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 LAEFpost was associated with the recurrence of AF (hazard ratio/10% increase: 0.62, 95% confidence interval: 0.51-0.75, P < 0.0001). LAEFpost 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 LAEFpost (< 26.36%, N = 100) and those with preserved LAEFpost (≥ 26.36%, N = 516) was 40% and 79%, respectively (P < 0.0001). The predictors of reduced LAEFpost were low pre-ablation LAEF, high pre-ablation LA volume, low body mass index (BMI), and female sex. Further, reduced LAEFpost was associated with the total number of ablation sessions and extra-pulmonary vein LA ablation. In conclusion, reduced LAEFpost was associated with recurrence of AF after ablation. Advanced LA remodeling, low BMI, and female sex could predict reduced LAEFpost. Although additional ablation was associated with reduced LAEFpost, it remains unclear whether reduced LAEFpost resulted from the additional ablation. Reduced LAEFpost might help stratify patients with ablation-refractory AF.

From Left Atrial Dimension to Curved M-Mode Speckle-Tracking Images: Role of Echocardiography in Evaluating Patients with Atrial Fibrillation.

Left atrial (LA) enlargement and dysfunction increase the risk of atrial fibrillation (AF). Traditional echocardiographic evaluation of the left atrium has been limited to dimensional and semi-quantification measurement of the atrial component of ventricular filling, with routine measurement of LA function not yet implemented. However, functional parameters, such as LA emptying fraction (LAEF), may be more sensitive markers for detecting AF-related changes than LA enlargement. Speckle-tracking echocardiography has proven to be a feasible and reproducible technology for the direct evaluation of LA function. The clinical application, advantages, and limitations of LA strain and strain rate need to be fully understood. Furthermore, the prognostic value and utility of this technique in making therapeutic decisions for patients with AF need further elucidation. Deep learning neural networks have been successfully adapted to specific tasks in echocardiographic image analysis, and fully automated measurements based on artificial intelligence could facilitate the clinical diagnostic use of LA speckle-tracking images for classification of AF ablation outcome. This review describes the fundamental concepts and a brief overview of the prognostic utility of LA size, LAEF, LA strain and strain rate analyses, and the clinical implications of the use of these measures.

Associations of Left Atrial Function and Structure With Supraventricular Ectopy: The Multi-Ethnic Study of Atherosclerosis.

Background High levels of supraventricular ectopy are associated with greater risk of atrial fibrillation, stroke, and death. Little information is available about differences by race/ethnicity in the extent of supraventricular ectopy, or about whether high levels of supraventricular ectopy are associated with impaired left atrial (LA) function and LA enlargement. Methods and Results In the MESA (Multi-Ethnic Study of Atherosclerosis), 1148 participants (47% men; mean age, 67 years) had cardiovascular magnetic resonance imaging in 2010 to 2012, followed by 14-day ambulatory electrocardiographic monitoring in 2016 to 2018. We analyzed participant characteristics and cardiovascular magnetic resonance measures of LA function and structure in relation to average count of premature atrial contractions (PACs) per hour and average number of runs per day of supraventricular tachycardia. In adjusted regression analyses, older age, male sex, White race, elevated NT-proBNP (N-terminal pro-B-type natriuretic peptide), and a history of clinically detected atrial fibrillation were associated with more PACs/hour. Chinese and Hispanic participants had on average fewer PACs/hour than White participants (Chinese participants, 31% less [95% CI, 8%-49%]; Hispanic participants, 38% less [95% CI, 19%-52%]). Greater LA total emptying fraction was associated with fewer PACs/hour (per SD, 16% fewer PACs/hour [95% CI, 7%-25% fewer PACs/hour]). Larger LA minimum volume was associated with more PACs/hour (per SD, 7% more PACs/hour [95% CI, 2%-13% more PACs/hour]). Associations of LA volumes with runs of supraventricular tachycardia/day were similar in direction but were weaker. Conclusions Impaired LA function and LA enlargement were associated with more PACs/hour on extended ambulatory electrocardiographic monitoring. Measurement of supraventricular ectopy may provide information about the extent of atrial myopathy.

The Prognostic Value of Left Atrial Reservoir Functional Indices Measured by Three-Dimensional Speckle-Tracking Echocardiography for Major Cardiovascular Events.

BACKGROUND: Left atrial (LA) volume and left ventricular longitudinal strain (LVLS) have significant prognostic values for major cardiovascular events (MACEs). Prognostic values of LA reservoir functional indices measured by 3-dimensional (3D) speckle-tracking echocardiography (STE) were evaluated.Methods and Results:A total of 264 patients, who underwent 2-dimensional (2D) echocardiography and 3DSTE for various underlying heart diseases, were followed up to record MACE. After a mean follow up of 547±435 days, 30 patients developed MACE: 7 cardiac deaths, 6 strokes, 1 non-fatal myocardial infarction, and 22 admissions for heart failure (5 of these had cardiac death after discharge, whereas 1 sustained stroke after discharge). Receiver operating characteristic curve analysis was performed to determine the optimal cut-off levels of 4 LA functional indices: LA emptying fraction (LAEmpF), LA longitudinal strain (LALS), LA circumferential strain (LACS), and LA area change ratio (LAAC), using 3DSTE. Among these factors, 2DLVLS, 3DLAEmpF, and 3DLALS demonstrated a higher hazard ratio (>5.0) than other variables. The 3DLAEmpF and 3DLALS had a higher average treatment effect (ATE) and ATE on the treated (ATT), respectively, than the other indices after propensity score matching. Addition of 3DLAEmpF to the base model using clinical variables and LV ejection fraction or 2DLVLS demonstrated higher prognostic power. CONCLUSIONS: LAEmpF calculated using 3DSTE possessed additive prognostic values for the prediction of MACE.

Comparisons of Left Atrial Functional Parameters with Left Ventricular Diastolic Dysfunction in a Large Taiwanese Population with Normal Left Ventricular Ejection Fraction According to Age.

BACKGROUND: Recent studies have shown that left atrial (LA) volume is a sensitive morphophysiological indicator of the severity of LV dysfunction and may also be a useful index of cardiovascular risk. In this study, we performed comparisons among left atrial (LA) functional parameters for predicting age-related diastolic dysfunction. METHODS: Echocardiography was performed in 2248 healthy participants with a low possibility of heart disease according to the decennium of age, and reference values were established. Progressive diastolic dysfunction paralleled increasing age and could be well identified by traditional and advanced echocardiographic parameters, including mitral inflow pattern, tissue Doppler parameters, and LA volume. RESULTS: Regarding LA functional parameters analyzed based on the decennium of age, left atrial ejection fraction (LAEF) and emptying fraction could not represent aging diastolic dysfunction well, but LA expansion index ((Volmax - Volmin) × 100% / Volmin) could. Volmax indicated maximal LA volume and Volmin indicated minimal LA volume. In assessments of diastolic dysfunction with receiver operating characteristic curve analysis, the best cut-off value of LA expansion index was < 100%, with an area under the curve (AUC) of 0.86, sensitivity of 80%, and specificity of 74%. LAEF < 30% (AUC 0.76, sensitivity 67%, specificity 70%) and LA emptying fraction < 50% (AUC 0.80, sensitivity 72%, specificity 71%) were also useful but performed less well. CONCLUSIONS: Compared with other LA functional parameters, LA expansion index can well represent age-related diastolic dysfunction.

Reduced Left Atrial Emptying Fraction and Chymase Activation in Pathophysiology of Primary Mitral Regurgitation.

Increasing left atrial (LA) size predicts outcomes in patients with isolated mitral regurgitation (MR). Chymase is plentiful in the human heart and affects extracellular matrix remodeling. Chymase activation correlates to LA fibrosis, LA enlargement, and a decreased total LA emptying fraction in addition to having a potential intracellular role in mediating myofibrillar breakdown in LA myocytes. Because of the unreliability of the left ventricular ejection fraction in predicting outcomes in MR, LA size and the total LA emptying fraction may be more suitable indicators for timing of surgical intervention.

Impact of baseline left atrial function on long-term outcome after catheter ablation for paroxysmal atrial fibrillation.

BACKGROUND: Left atrial (LA) size is an established predictor of recurrence after catheter ablation for paroxysmal atrial fibrillation (PAF). We investigated the impact of baseline LA function on recurrence after PAF ablation and compared the predictive values of LA function with those of LA size. METHODS: We retrospectively investigated 292 consecutive patients who underwent PAF ablation (median follow-up: 3.0 years). All patients had their preoperative LA volume (LAV) assessed using cardiac computed tomography under sinus rhythm. We used LA emptying fraction (LAEF) as an indicator of LA function and assessed the association between baseline LAEF and recurrence after initial ablation using a multivariate Cox hazard model. Then, we performed receiver operating characteristic analysis for predicting recurrence after single and multiple procedures and compared the c-statistics of LAEF and indexed maximum and minimum LAV (LAVImax and LAVImin) RESULTS: In a multivariate Cox hazard model, LAEF was strongly associated with recurrence after a single procedure [hazard ratio (HR): 0.968, 95% confidence interval (CI): 0.951-0.985, p < 0.001]. In the receiver operating characteristic analysis for predicting recurrence, the predictive accuracy of LAEF was mild after a single procedure [area under the curve (AUC): 0.666, p < 0.001] and moderate after multiple procedures (AUC: 0.701, p < 0.001). The c-statistic of LAEF was significantly higher than those of LAVImax and LAVImin after a single procedure (p < 0.05, for both). After adjustment for factors related to reduced LAEF (increased serum brain natriuretic peptide, age, LA diameter, and reduced left ventricular ejection fraction), it was still associated with recurrence (HR: 0.964, 95% CI: 0.946-0.982, p < 0.001). CONCLUSIONS: LAEF was associated with recurrence after PAF ablation. LA function is a more useful predictor than LA size.

Left Atrial Function Determined by Echocardiography Predicts Incident Heart Failure in Patients With STEMI treated by Primary Percutaneous Coronary Intervention.

OBJECTIVES: To assess the comparative effectiveness of left atrial (LA) functional parameters (left atrial emptying fraction (LAEF), left atrial expansion index (LAi) and minimal left atrial volume index (MinLAVI)) with that of LA volume index (LAVI) in predicting heart failure (HF) and death following ST-elevated myocardial infarction (STEMI). BACKGROUND: HF is common following STEMI. Enlarged LA volume as determined by echocardiography predicts adverse outcome following STEMI. However, whether echocardiographic parameters of LA function, such as LAEF, LAi and MinLAVI, are superior to LAVI for predicting prognosis following STEMI is unknown. METHODS AND RESULTS: A total of 369 patients with STEMI but without atrial fibrillation or HF who were treated with primary percutaneous coronary intervention were prospectively enrolled in the period between September 2006 and December 2008. Patients underwent echocardiography shortly after STEMI. The maximal and minimal LA volumes were measured using the biplane area-length method. LAVI, MinLAVI (minimal LA volume indexed to body surface area), LAEF ((maximal LA volume-minimal LA volume)/maximal LA volume), and LAi ((maximal LA volume-minimal LA volume)/minimal LA volume) were calculated. The endpoint was a composite consisting of HF or death from any cause. During a median follow-up of 66 months (interquartile range: 50-73 months), 112 patients reached the endpoint (68 HFs, 44 deaths). Following adjustment for clinical, biochemical and echocardiographic variables, only LAEF remained an independent predictor of the composite outcome, whereas LAVI did not (LAEF: HR 1.25, P = 0.043, per 1 SD decrease) (LAVI: HR 1.01, P = 0.91, per 1 SD increase). CONCLUSION: In patients with STEMI who were treated with primary percutaneous coronary intervention, LAEF, as measured by echocardiography shortly after infarction, was superior to LAVI in predicting incident HF and death.

Echocardiographic and Biochemical Factors Predicting Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation-An Observational Study.

Background: RFA is a well-established treatment for symptomatic patients with AF. However, the success rate of a single procedure is low. We aimed to investigate the association between the risk of recurrence of atrial fibrillation (AF) after a single radiofrequency ablation (RFA) procedure and cardiac neurohormonal function, left atrial (LA) mechanical function as well as proteins related to inflammation, fibrosis, and apoptosis. Methods and Results: We studied 189 patients undergoing RFA between January 2012 and April 2014, with a follow-up period of 12 months. A logistic regression analysis was performed to investigate the association between pre-ablation LA emptying fraction (LAEF), MR-proANP, Caspase-8 (CASP8), Neurotrophin-3 (NT3), and the risk for recurrence of AF after a single RFA procedure. 119 (63.0%) patients had a recurrence during a mean follow-up of 402 ± 73 days. An increased risk of recurrence was associated with: Elevated MR-proANP (fourth quartile vs. first quartile: HR, 2.80 (95% CI, 1.14-6.90]; P = 0.025); Low LAEF (fourth quartile vs. first quartile: hazard ratio [HR], 2.41 [95% CI, 1.01-5.79]; P = 0.045); Elevated CASP8 (fourth quartile vs. first quartile: HR 12.198 95% CI 2.216-67.129; P = 0.004); Elevated NT-3 (fourth quartile vs. first quartile: HR 7.485 95% CI 1.353-41.402; P = 0.021). In a receiver operating characteristic curve analysis, the combination of MR-proANP, CASP8, and NT3 produced an area under the curve of 0.819; CI 95% (0.710-0.928). Conclusions: Patients with better LA mechanical function and lower levels of atrial neurohormones as well as of proteins related to fibrosis and apoptosis, have a better outcome after an RFA procedure. Unique identifier: No. NCT01553045 (https://clinicaltrials.gov/ct2/show/NCT01553045?term=NCT01553045&rank=1).

Left atrial size and total atrial emptying fraction in atrial fibrillation progression.

BACKGROUND: Left atrial (LA) size and low-voltage areas (LVA) mirror atrial fibrillation (AF) progression. Whether these factors are important for the impairment of total atrial emptying fraction is understudied. OBJECTIVE: The aim of the present analysis was to investigate the association between LA volume and total atrial emptying fraction with AF progression phenotypes: persistent AF and LVA. METHODS: Patients undergoing first AF ablation were included in the analysis. LVA were determined using high-density maps and defined as <0.5 mV. All patients underwent cardiovascular magnetic resonance imaging before the intervention. Cardiovascular magnetic resonance data (LA volume, LA emptying fraction [LA-EF], and right atrial emptying fraction [RA-EF]) were measured in all patients. RESULTS: The study population included 211 patients (65 ± 11 years; 124 (59%) men; 122 (58%) persistent AF; 54 (26%) LVA). There were 4 disease progression groups: paroxysmal AF without LVA, paroxysmal AF with LVA, persistent AF without LVA, and persistent AF with LVA. While LA volume increased according to the AF progression phenotype (98 ± 27, 145 ± 34, 134 ± 41, 141 ± 39 mL, respectively; P < .001), total LA-EF (51% ± 17%, 32% ± 17%, 33% ± 17%, 22% ± 11%; P < .001) and RA-EF (47% ± 13%, 36% ± 17%, 30% ± 16%, 23% ± 12%; P < .001) decreased. In multivariable analysis, age (odds ratio [OR] 1.084; 95% confidence interval [CI] 1.028-1.142; P = .003), persistent AF (OR 3.478; 95% CI 1.117-10.830; P = .031), and total LA-EF (OR 0.933; 95% CI 0.899-0.968; P < .001) showed a significant association for LVA. Using receiver operating characteristic curve analysis, LA-EF (area under the curve 0.778; 95% CI 0.711-0.846; P < .001) and RA-EF (area under the curve 0.726; 95% CI 0.650-0.802; P < .001) were significantly associated with the absence of LVA. CONCLUSION: LVA and persistent AF are associated with worse total atrial emptying fraction.

Effect of cryoballoon and radiofrequency ablation for pulmonary vein isolation on left atrial function in patients with nonvalvular paroxysmal atrial fibrillation: A prospective randomized study (Cryo-LAEF study).

BACKGROUND: Isolation of the pulmonary veins (PVI) has become a mainstay in atrial fibrillation (AFib) therapy. Lesions in left atrial tissue lead to scar formation and this may affect left atrial function. METHODS: Patients with paroxysmal AFib were randomly assigned in a 1:2 allocation scheme to radiofrequency (RF) ablation or cryoballoon. Real-time three-dimensional echocardiography was performed (under sinus rhythm in all cases) before ablation and at 1 and 3 months to evaluate the left atrial functional indices. The primary outcome measure was change in left atrial ejection fraction (LAEF) at 1 month. RESULTS: 120 patients were randomized (80 to cryoballoon, 40 to RF). The absolute change in LAEF at 1 month was 4.0 (Q1-Q3, -0.1to 7.6)% in the cryoballoon group and -0.8 (Q1-Q3, -1.9 to 0.9)% in the RF group (P < 0.001 for the comparison between groups). At 3 months, the corresponding changes were 6.7 (Q1-Q3, 3.4-11.2)% and 0.7 (Q1-Q3, -0.7 to 3.5)%, respectively (P < 0.001). Overall, the rate of patients with lower LAEF at 3 months compared to baseline was 2.5% in the cryoballoon group and 32.5% in the RF group (P < 0.001). AFib recurrence rate at 6 months was higher in patients with decreased LAEF (odds ratio, 6.2; 95% confidence interval, 2.0-19.5; P = 0.002). CONCLUSION: The Cryo-LAEF study prospectively compared the effects of RF and cryoballoon ablation on left atrial function. Both at 1 and 3 months postablation, LAEF was either improved or stable in both ablation groups.

Real-time three-dimensional echocardiographic left heart parameters in healthy indian adults.

OBJECTIVE: Cardiac chamber dimensions are race and anthropometry dependent. We determined the age and gender specific 3-Dimensional echocardiographic (3DE) reference values for dimensions and function of left ventricle (LV) and left atrium (LA) in normal Indian adults. METHODS: This single center prospective study enrolled 133 adult Indians free of heart disease and/or hypertensions, subjecting them to 3DE measurements of left atrial (LA) & left ventricular (LV) volumes, function and left ventricular mass (LVM). The higher limits of normal cut-offs were determined for these parameters and their dependency on age, gender and anthropometry were analyzed. RESULTS: The body surface area (BSA) corrected higher limit cut-offs were: 59.37ml/m2 for LV end diastolic volume (59.19ml/m2 and 59.61ml/m2 for men and women, respectively; P=NS); 23.48ml/m2 for LV end systolic volume (23.27ml/m2 and 23.11ml/m2 for men and women, P=NS). Mean LVEF was 64.79%±7.26 (62.99%±6.51 and 67.05%±7.58 in men and women, P=NS). Men had higher LVM than women (119.79g±23.95 vs. 103.26g±23.76, P<0.001), this difference disappeared after BSA indexing. The higher limit cut-offs for normal LA volumes were 20.49ml for minimum volume (21.18ml and 19.46ml for men and women, P=NS) and 39.76ml for maximum volume (39.60ml and 40.03ml in men and women, P=NS). The parameters were smaller compared to western populations but the differences attenuated after BSA indexing. CONCLUSIONS: The study reports normal 3DE parameters of size and function of left heart chambers in Indians.

Left atrial volume and function in dogs with naturally occurring myxomatous mitral valve disease.

OBJECTIVE: Myxomatous mitral valve disease (MMVD) induces progressive left atrial (LA) enlargement. The LA modulates left ventricular filling and performance through its reservoir, conduit, and contractile function. Assessment of LA size and function may provide valuable information on the level of cardiac compensation. Left atrial function in dogs with naturally occurring MMVD remains largely unexplored. The objective of this study was to evaluate LA volume and function in dogs with naturally occurring MMVD. ANIMALS: This prospective study included 205 client-owned dogs of different breeds, 114 healthy dogs, and 91 dogs with MMVD of different disease severities. METHODS: Using two-dimensional echocardiography, the biplane area-length method was applied to assess LA volume and calculate volumetric indices of LA reservoir, conduit, and contractile function. RESULTS: Left atrial volume and LA stroke volume increased, whereas LA reservoir and contractile function decreased with increasing disease severity. A maximal LA volume <2.25mL/kg was the optimal cut off identified for excluding congestive heart failure in dogs with chronic MMVD with a sensitivity of 96% and a specificity of 100%. An active LA emptying fraction <24% and/or a LA expansion index <126% were suggestive of congestive heart failure in dogs with chronic MMVD with a sensitivity of 77% and a specificity of 89% and a sensitivity of 82% and a specificity of 82%, respectively. CONCLUSION: Dogs with MMVD appear to have larger LA volumes with poorer LA function. Deteriorating LA function, characterized by a decreasing reservoir and active contractile function, was evident in dogs with MMVD with increasing disease severity.

Effect of Sex Differences on the Association Between Stroke Risk and Left Atrial Anatomy or Mechanics in Patients With Atrial Fibrillation.

BACKGROUND: Embolic stroke in atrial fibrillation is more prevalent in women than in men, yet the basis for this difference remains unclear. This study seeks to elucidate whether there are any sex differences in the relationships between stroke risk (CHADS2 score, CHA2DS2-VASc score without a sex category, and estimated stroke rate) and left atrial (LA) anatomy or mechanics in patients with atrial fibrillation. METHODS AND RESULTS: LA emptying fraction and global peak atrial longitudinal strain were assessed in 414 subjects with paroxysmal or persistent atrial fibrillation (156 women and 258 men). Linear regression models with an interaction term were performed to test the effect of sex difference on associations between the embolic risk and LA function or anatomy. Sensitivity analyses were performed in 228 age, heart rate, and rhythm-matched subjects (114 women and men). Women were older and had larger LA volumes and lower LA mechanics than men. Significant negative association between the CHADS2 score and LA emptying fraction was only demonstrated in women with a significant interaction between sexes. Similar significant interactions were found in global peak atrial longitudinal strain but not in LA volume. These findings were corroborated in the comparisons against CHA2DS2-VASc score without a sex category and the estimated stroke rate. Sensitivity analyses in the matched subgroup also confirmed the robustness of these sex differences in LA emptying fraction, but less so in global peak atrial longitudinal strain. CONCLUSIONS: Significant sex interactions on the association between global LA function and risk stratification schemes exist, which may be a reason for the higher prevalence of embolic stroke in women.