Atrial Conduction Time Research Articles

Echocardiographic associates of impaired sleep quality in patients with anxiety and depression

Abstract Objective Sleep health, mental health and cardiovascular health are multidimensional constructs that are strongly associated with each other. Anxiety and depression are the most common psychiatric diseases in the community and frequently comorbid in routine clinical practice. This study sought to investigate whether there is an association between sleep quality and echocardiographic parameters in patients with anxiety and/or depression. Methods The clinical and instrumental find­ings of consecutive patients diagnosed with either of anxiety disorders and/or depressive disorders and underwent cardiac examination in our tertiary center on the same day were retrospectively reviewed. The diagnosis was made by a psychiatrist according to the criteria listed in the fifth edition of The Diagnostic and Statistical Manual of Mental Disorders. Afterwards, Hospital Anxiety and Depression Scale (HADS) and Pittsburgh Sleep Quality Index (PSQI) were applied to patients to assess symptom severity and sleep quality, respectively. Subsequent to psychiatric examination, the patients underwent echocardiographic examination that includes two-dimensional conventional echocardiography, tissue doppler imaging (TDI) echocardiography, atrial conduction times, and left atrium (LA) volumes and functions. Results The final study population consisted of 167 patients and divided into two groups according to their PSQI score: PSQI<5 (normal sleep quality) (n=32) and PSQI≥5 (impaired sleep quality) (n=135). Aortic diameter, left ventricular (LV) end-systolic diameter, LV end-diastolic and -systolic volume, LV stroke volume and LV stroke volume index, LV outflow tract velocity–time integral (LVOT-VTI), and LA conduit volume calculations were significantly lower in patients with impaired sleep quality compared to patients with normal sleep quality. The other echocardiographic parameters including LV systolic functions, doppler and TDI echocardiography indices, atrial conduction times, atrial mechanical functions including LA function index (LAFI) were similar among groups. Correlation analysis yielded a negative, weak but statistically significant correlation between LAFI and PSQI score (r=-0.17, p=.030) (Figure 1A). Left intra-AEMD positively and significantly correlated with PSQI score at a weak level (r=0.16, p=.043) (Figure 1B). Aortic diameter, LV stroke volume index, LVOT-VTI and conduit volume were determined as echocardiographic parameters significantly associated with impaired sleep quality in univariate analysis. Among these parameters, only conduit volume remained as significant and independent associate of impaired sleep quality in multivariate logistic regression analysis (Odds ratio:0.91, 95% Confidence interval:0.85-0.98, p=.018) (Table 1). Conclusion There is an independent association between LA conduit volume and impaired sleep quality in patients suffering from anxiety and/or depressive disorders.Figure 1Table 1

Predictive value of total atrial conduction time for developing cerebrovascular stroke in patients with sinus rhythm and normal left ventricular systolic function, a case-control study

Abstract Background Stroke is the second leading cause of death worldwide. Recently, atrial cardiopathy has become recognized as a substantial risk factor for cerebrovascular stroke. Greater LA size is linked to stroke in AF patients, but few data linking LA size to stroke in population with sinus rhythm. Purpose To investigate the value of total atrial conduction time (TACT) measured non-invasively by assessing PA-TDI duration as a predictor of stroke in patients who initially presented with sinus rhythm and have normal LV systolic function. Methods In our case-control study, we included 156 patients with acute ischemic stroke and 50 control subjects all presented in sinus rhythm and normal LV systolic function. All participants underwent echocardiography. The bi-plane modified Simpson's approach was used to determine the LV-EF. The left atrial (LA) diameter was measured also left atrial volume index (LAVI) was assessed. The PA-TDI interval was used to estimate the TACT. In the apical four-chamber view, the pulsed-wave tissue Doppler sample was positioned on the lateral and septal walls of the LA above the mitral annulus. The time between the onset of the P wave (lead II) and the peak of the A' wave was called the PA-TDI interval. Also, speckle tracking indices of LA strain were measured. Results LA volume index was larger in the stroke group (39.24±4 versus 33.6±2.8, p: 0.01), PA-TDI duration showed statistical highly significant difference between both groups (165.94±21.695 versus 99.4±22.960, p: <0.001). There were significantly impaired LAS parameters in the stroke group (LA reservoir, contraction & conduit strain, 22.7%, -6.6% & -16.1% versus 40%, -12%, and − 27% in the control group with P < 0.000). ROC curve showed the best cutoff point for LA volume index is >42.2 ml/m2 for prediction of stroke with area under the curve (AUC): 0.7, p value is 0.005. ROC curve showed the best cutoff point for PA-TDI is >155.5 ms. with AUC: 0.9, 90% sensitivity, 91% specificity, p value: <0.001. ROC curve showed that LA reservoir strain and LA stiffness can independently predict stroke at cut-off values of 30% & 24.5% respectively, P < 0.001. Multivariate logistic regression analysis showed that hypertension, LA volume index, LA stiffness and PA-TDI duration are independent predictors of stroke (p: < 0.05, < 0.05, < 0.01 and < 0.001 respectively). Conclusions The assessment of electromechanical asynchrony by measuring the PA-TDI duration may help to predict patients at risk for stroke. It is easy to measure without the need for special software like speckle tracking indices. We also advise patients who exceed the cutoff points of LA volume index and PA-TDI duration to receive antithrombotic therapy for better stroke prevention. Also we recommend adding PA-TDI to CHA2DS2-VASC-HSF score to assess stroke risk in patients with sinus rhythm and paroxysmal AF during their sinus rhythm intervals.

Left atrial morpho-functional parameters and their correlation with other phenotypic and functional characteristics of hypertrophic cardiomyopathy

Abstract Background Left atrial (LA) volume index (LAVI), LA reservoir strain (LARS) and total atrial conduction time (TACT) (estimated by tissue Doppler imaging) are morphological and functional parameters reflecting LA structural and electrical remodeling, connected to atrial fibrillation development and heart failure progression in various substrates. In hypertrophic cardiomyopathy (HCM), correlation of the above-mentioned parameters with other disease characteristics is not fully investigated. Purpose Aim of this study was to estimate the prevalence of atrial myopathy characteristics such as increased LAVI, impaired LARS and elongated TACT in a cohort of HCM patients without AF history and investigate their correlation with other phenotypic and functional characteristics of the disease such as left ventricular (LV) hypertrophy magnitude, fibrosis extent and diastolic dysfunction grade. Methods We included 100 HCM patients (54±21 years, 75% male, maximum wall thickness 19±3.4mm) without history of atrial fibrillation who have consecutively undergone 2D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). TACT and LARS measurement is shown on left panel. Burden of fibrosis (percentage of LV mass) was defined by LGE extent (>5 standard deviations compared to nulled myocardium) in CMR slices. Results All HCM patients had preserved EF (60±7.5%), while 28 (28%) presented outflow tract obstruction and 10 (10%) diastolic dysfunction stage≥2. LGE was observed in 64 patients (64%) occupying 8±5% of left ventricular (LV) mass. Mean TACT was 140±22 msec, with LAVI being 32±16 mL/m2 and LARS 26±14%. Among HCM demographic, phenotypic and functional characteristics tested, age and LV mass index were found to be the only independent regressors of TACT (r=0.54, p<0.0005 and r=0.44, p=0.002 respectively, right upper panel), while E/E’ (r=-0.44, p=0.003) and fibrosis extent (r=0.36, p=0.02) were the strongest predictors of LARS and LAVI values respectively (right lower panel). Conclusions Atrial myopathy parameters seem to correlate with various morphological and functional characteristics of HCM. Atrial electro-mechanical delay assessed through TDI based TACT correlates significantly with LVMI, whereas LARS and LAVI are strong regressors of elasticity properties, partially expressed through diastolic function and underlying fibrosis.

Prediction of New-Onset Atrial Fibrillation in Transcatheter Aortic Valve Implantation.

This study investigates the association between prolonged total atrial conduction time and the development of new-onset atrial fibrillation (AF) following transcatheter aortic valve implantation (TAVI). We enrolled 307 patients who underwent TAVI. Total atrial conduction time was calculated as the time between the onset of the P wave on the electrocardiography and the peak of the a' wave velocity (PA-TDI duration) on tissue Doppler imaging echocardiography. A total of 263 patients were analyzed after excluding 44 with pre-existing AF. Of these 263 patients, 47 (17.8%) experienced new-onset AF after the TAVI procedure. The new-onset AF group had an older median age (80.6 vs. 77.5 years) and a higher incidence of paravalvular aortic regurgitation than those without AF (none 29.8%, mild 46.8%, moderate 23.4%). The new-onset AF group had increased end-systolic diameter (35.0 vs. 31.7 mm, p = 0.03), left atrial diameter (44.7 vs. 41.9 mm, p = 0.049), and PA-TDI duration (137.0 vs. 125.4 ms, p = 0.009). Older age, the presence of paravalvular aortic regurgitation, and prolonged PA-TDI duration were independently associated with new-onset AF in multivariate analysis. The optimal cut-off value for PA-TDI duration was 123.5 ms. AF in patients treated with TAVI may pose significant risks for morbidity and mortality. PA-TDI duration, a readily available echocardiographic parameter, can detect patients with a high risk of new-onset AF.

Characterization of remodeling processes in the atria of atrioventricular block dogs: Utility as an early-stage atrial fibrillation model

To characterize utility of atrioventricular block (AVB) dogs as atrial fibrillation (AF) model, we studied remodeling processes occurring in their atria in acute (<2 weeks) and chronic (>4 weeks) phases. Fifty beagle dogs were used. Holter electrocardiogram demonstrated that paroxysmal AF occurred immediately after the production of AVB, of which duration tended to be prolonged in chronic phase. Electrophysiological analysis showed that inter-atrial conduction time and duration of burst pacing-induced AF increased in the chronic phase compared with those in the acute phase, but that atrial effective refractory period was hardly altered. Echocardiographic study revealed that diameters of left atrium, right pulmonary vein and inferior vena cava increased similarly in the acute and chronic phases. Histological evaluation indicated that hypertrophy and fibrosis in atrial tissue increased in the chronic phase. Electropharmacological characterization showed that i.v. pilsicainide effectively suppressed burst pacing-induced AF with increasing atrial conduction time and refractoriness of AVB dogs in chronic phase, but that i.v. amiodarone did not exert such electrophysiological effects. Taken together, AVB dogs in chronic phase appear to possess such pathophysiology as developed in the atria of early-stage AF patients, and therefore they can be used to evaluate drug candidates against early-stage AF.

The Role of Galectin-3 Levels for Predicting Paroxysmal Atrial Fibrillation in Patients with Embolic Stroke of Undetermined Source.

Background/Objectives: Paroxysmal atrial fibrillation (PAF) is an important cause that is thought main potential factor in Embolic stroke of undetermined source (ESUS). Extended Holter ECG is an expensive and time-consuming examination. It needs another tools for predicting PAF in ESUS patients. In this study, serum galectin-3 levels, ECG parameters (PR interval, P wave time and P wave peak time) LA volume index, LA global peak strain and atrial electromechanical conduction time values were investigated for predicting PAF. Methods: 150 patients with ESUS and 30 volunteers for the control group were recruited to study. 48-72 h Holter ECG monitoring was used for detecting PAF. Patients were divided into two groups (ESUS + PAF and ESUS-PAF) according to the development of PAF in Holter ECG monitoring. Results: 30 patients with ESUS whose Holter ECG monitoring showed PAF, were recruited to the ESUS + PAF group. Other 120 patients with ESUS were recruited to the ESUS-PAF group. PA lateral, PA septum, and PA tricuspid were higher in the ESUS + PAF group (p < 0.001 for all). Serum galectin-3 levels were significantly higher in ESUS + PAF than in ESUS-PAF and control groups (479.0 pg/mL ± 435.8 pg/mL, 297.8 pg/mL ± 280.3 pg/mL, and 125.4 ± 87.0 pg/mL, p < 0.001, respectively). Serum galectin-3 levels were significantly correlated with LAVI, PA lateral, and global peak LA strain (r = 0.246, p = 0.001, p = 0.158, p = 0.035, r = -0.176, p = 0.018, respectively). Conclusion: Serum galectin-3 levels is found higher in ESUS patients which developed PAF and Serum galectin-3 levels are associated LA adverse remodeling in patients with ESUS.

The Impact of Sodium-Glucose Cotransporter-2 Inhibitors on Atrial Electromechanical Conduction Time.

This study aims to explore the impact of sodium-glucose cotransporter-2 (SGLT-2) inhibitors, a newer class of oral antidiabetic drugs, on atrial electromechanical delay (EMD) in patients with type 2 diabetes mellitus (DM). This is particularly relevant given the significantly higher incidence of atrial fibrillation (AF) in diabetic patients compared to the general population. Atrial electromechanical delay is recognized as an important factor influencing the development of atrial fibrillation. This study included 30 type 2 DM patients (53.3% female, mean age 60.07 ± 10.03 years), initiating treatment with SGLT-2 inhibitors. The patients were assessed using echocardiography at baseline and again at 6 months, focusing on basic echocardiographic parameters and atrial electromechanical delay times (EMD) measured via tissue Doppler imaging. No significant changes were observed in intra-atrial EMD times. However, significant reductions were noted in interatrial EMD times, decreasing from 15.13 ± 5.87 ms to 13.20 ± 6.12 ms (P = 0.029). Statistically significant shortening occurred in lateral pulmonary acceleration (PA) times (from 58.73 ± 6.41 ms to 54.37 ± 6.97 ms, P < 0.001), septal PA times (from 50.90 ± 6.02 ms to 48.23 ± 5), and tricuspid PA times (from 43.60 ± 6.28 ms to 41.30 ± 5.60 ms, P = 0.003). Additionally, there was a significant reduction in the E/e' ratio from 8.13 ± 4.0 to 6.50 ± 2.37 (P = 0.003). SGLT-2 inhibitors might positively influence atrial electromechanical conduction, reducing DM-related functional impairments and the risk of arrhythmias, particularly AF.

Disturbed Atrial Conduction in Patients with Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy (DMD)-related cardiomyopathy is associated with hemodynamic and conduction abnormalities and begins at an early age with subtle symptoms. The study population included 55 patients with DMD and 54 healthy controls. We compared electrocardiogram (ECG), conventional echocardiography, and tissue Doppler imaging (TDI) assessments between patients with DMD and healthy controls. Also, we investigated atrial electromechanical delay, which has not been previously studied in DMD patients. Mitral, septal, and tricuspid segments were analyzed by TDI. The mean age was 13.6 ± 2.5 years (range, 9.3-17.9 years) in the patient group and 12.8 ± 2.6 years (range, 8-17.5 years) in the control group (P = .1). Patients had higher heart rates, longer QTc intervals, and P-wave dispersion (PWD) than controls (P < .001, P = .004, P < .001, respectively). The patient group had larger left ventricular end-systolic dimension (P < .001), lower left ventricular ejection fraction (EF) (P < .001), MAPSE (P < .001), TAPSE (P < .001), and mitral-E/A (P = .029) values than control subjects. Myocardial performance index (P < .001) was higher, and the E'/A' ratio (P < .001) was lower at all 3 segments in the patient group. Also, atrial electromechanical delay was longer in the patient group at these segments (P < .001). Patients had significantly longer interatrial (P = .033) electromechanical conduction delays. EF was negatively correlated with atrial conduction time variables. We have shown deterioration in systolic and diastolic function in both ventricles, PWD, and atrial conduction in children with DMD. Patients with DMD may be at risk of atrial arrhythmias due to disturbed atrial conduction.

Evaluation of atrial conduction properties and atrial arrhythmia propensity in vitiligo patients

Aims: Vitiligo is a skin condition characterized by melanocyte loss. It is thought to have a robust association with various systemic and metabolic disorders, such as insulin resistance, atherosclerotic cardiovascular disease, and metabolic syndrome. Atrial fibrillation (AF) is a prevalent disorder in clinical practice and appears to be predictable by atrial electromechanical delay (EMD). This study aimed to detect atrial conduction time through tissue Doppler echocardiography, a non-invasive method used for patients with vitiligo. Methods: We conducted this study with 32 patients diagnosed with generalized vitiligo and 38 age- and sex-matched controls. We evaluated all participants' blood samples, including neutrophil/lymphocyte ratio (NLR), high-sensitivity C-reactive protein (hs-CRP), and other laboratory parameters. Then, we calculated atrial EMD, intra-atrial EMD, and left atrial EMD. Results: We found neutrophil count, NLR levels, and hs-CRP levels to be significantly higher in the vitiligo group (6 ± 1.4 vs. 4.5 ± 2.3, p = 0.001; 3.5 ± 1.4 vs. 2.5 ± 1.9, p = 0.024; 6.2 ± 1.9 mg/dl vs. 4.1 ± 1.3 mg/dl, p &lt; 0.001, respectively). In addition, inter-atrial and intra-atrial EMD were significantly higher in the vitiligo group compared to the control group (36.3 ± 8.5 vs. 24.2 ± 10.8, p &lt; 0.001; 18.1 ± 8.3 vs. 10.9 ± 5.8, p &lt; 0.001, respectively). Finally, left atrial EMD was higher in the vitiligo group, but we could not reach statistical significance (15.3 ± 6.9 vs. 13.2 ± 7.2, p = 0.33). Conclusion: We concluded that intra-atrial EMD and inter-atrial EMD were significantly prolonged in the vitiligo patients. Our results suggest that vitiligo patients are at risk for atrial fibrillation.

The value of serial echocardiography in risk assessment of patients with paroxysmal atrial fibrillation.

Progression from paroxysmal to persistent atrial fibrillation (AF) is associated with increased morbidity and mortality. We examined the association of left atrial (LA) remodeling by serial echocardiography, and AF progression over an extended follow-up period. Two-hundred ninety patients (mean age 61 ± 11years, 73% male) who underwent transthoracic echocardiography performed at first presentation for non-valvular paroxysmal AF (PAF) and repeat echocardiogram 1-year later, were followed for progression to persistent AF. LA and left ventricular (LV) dimensions, volumes, LA reservoir, conduit and booster pump strains, LV global longitudinal systolic strain (GLS) assessedby 2D speckle tracking, and PA-TDI (time delay between electrical and mechanical LA activation- reflecting the extent of LA fibrosis) were compared on serial echocardiography. Sixty-nine (24%) patients developed persistent AF over a mean follow-up period of 6.3years. At baseline, patients with subsequent persistent AF had larger LA dimensions (46mm vs. 42mm, p < 0.001), indexed LA volumes (41ml/m2 vs. 34ml/m2, p < 0.001), lower LA reservoir and conduit strain (17.6% vs. 27.6%, p < 0.001; 10.5% vs. 16.3%, p < 0.001; respectively) and longer PA-TDI (155ms vs. 132ms, p < 0.001) compared to the PAF group. Patients with subsequent persistent AF showed over time significant enlargement in LA volumes (from 37.7ml/m2 to 42.4ml/m2, p < 0.001), lengthening of PA-TDI (from 142.2ms to 162.2ms, p = 0.002), and decline in LA reservoir function (from 21.9% to 18.1%, p = 0.024) after adjusting for age, gender, diabetes and LV GLS. There were no changes in LA diameter, LA conduit or booster pump function. Conversely, the PAF group showed no decline in LA function. Patients who developed persistent AF had larger LAsize and impaired LA function and atrial conduction times at baseline, compared to patients who remained PAF. Over the 1-year time course of serial echocardiographic evaluation, there was progression of LA remodeling in patients who subsequently developed persistent AF, but not in patients who remained inPAF.

Echocardiographic parameters indicating left atrial reverse remodeling after catheter ablation for atrial fibrillation.

The echocardiographic parameters total atrial conduction time (PA-TDI duration), left atrial (LA) volume index (LAVI), and LA strain reflect adverse atrial remodeling and predict atrial fibrillation (AF). The aim of this study was to investigate echocardiographic parameters indicating reverse LA remodeling and potential associations with AF recurrence after pulmonary vein isolation (PVI). This prospective observational study consecutively enrolled patients scheduled for PVI for symptomatic AF. Electrocardiogram (ECG) test and transthoracic echocardiography were performed the day before and after PVI and again 3 months later. AF recurrence was determined by Holter ECG at 3 months, and telephone follow-up at 12 months, after PVI. The parameters of LA remodeling [PA-TDI, LAVI, and LA strain analysis: reservoir strain (LASr), conduit strain (LAScd), contraction strain (LASct)] were determined by transthoracic echocardiography. A total of 48 patients were included in the study (mean age: 61.4 ± 12.2 years). PA-TDI significantly decreased the day after PVI compared with the baseline (septal PA-TDI 103 ± 13 vs. 82 ± 14.9 ms, p ≤ 0.001; lateral PA-TDI 122.4 ± 14.8 vs. 106.9 ± 14.4 ms, p ≤ 0.001) and at the 3-month follow-up (septal PA-TDI: 77.8 ± 14.5, p ≤ 0.001; lateral PA-TDI 105.2 ± 16.1, p ≤ 0.001). LAVI showed a significant reduction at the 3-month follow-up compared with the baseline (47.7 ± 14.4 vs. 40.5 ± 9.7, p < 0.05). LASr, LAScd, and LASct did not change after PVI compared with the baseline. AF recurred in 10 patients after PVI (21%). Septal PA-TDI, septal a', and LAVI/a' determined the day after PVI were associated with AF recurrence. Changes in echocardiographic parameters of LA remodeling and function indicate that functional electromechanical recovery preceded morphological reverse remodeling of the left atrium after PVI. Furthermore, these changes in echocardiographic parameters indicating LA reverse remodeling after PVI may identify patients at high risk of AF recurrence.

Atrial Abnormalities in Brugada Syndrome: Evaluation With ECG Imaging

BackgroundPatients with Brugada syndrome (BrS) have an increased risk of arrhythmias, including atrial tachyarrhythmias (ATas). ObjectivesThe purpose of this study was to assess underlying atrial cardiomyopathy in BrS and the effect of ajmaline (AJM) test on the atrium of BrS patients using electrocardiogram imaging (ECGI). MethodsAll consecutive patients diagnosed with BrS in a monocentric registry were screened and included if they met the following criteria: 1) BrS diagnosed following current recommendations; and 2) ECGI map performed before and after AJM with a standard protocol. Consecutive patients with no structural heart disease or BrS who had undergone ECGI were included as a control group. Genetic analysis for SCN5A was performed in all BrS patients. Total atrial conduction time (TACT) and local atrial conduction time (LACT) were calculated from atrial ECGI. The primary endpoint was ATas during follow-up. ResultsForty-three consecutive BrS patients and 40 control patients were included. Both TACT and LACT were significantly prolonged in BrS patients compared with control patients. Furthermore, TACT and LACT were significantly higher after AJM administration and in BrS patients who were carriers of a pathogenic/likely pathogenic SCN5A variant. After a mean follow-up of 40.9 months, 6 patients experienced a first ATa occurrence (all in the BrS group, 13.9%). TACT was the only independent predictor of ATas with a cutoff of >138.5 ms (sensitivity 0.92 [95% CI: 0.83-0.98], specificity 0.70 [95% CI: 0.59-0.81]). ConclusionsECGI-calculated TACT and LACT are significantly prolonged in BrS patients compared with control patients, and in BrS patients after AJM. This may be consistent with a concealed atrial cardiomyopathy in BrS.

Total Atrial Conduction Time as a Predictor of Atrial Fibrillation Recurrence: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis aims to evaluate the predictive value of total atrial conduction time (TACT) assessed by tissue Doppler echocardiography (PA-TDI) in atrial fibrillation (AF) recurrence in patients following a rhythm-control strategy. A systematic approach following Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines was applied in electronic databases (Pubmed, Cochrane Library, and Web of Science), supplemented by scanning through studies' references. TACT was compared using a random-effects model and presented as a difference in means (MD). The primary endpoint was AF recurrence. Seven publications were included in this systematic review. The mean age of the patients ranged from 55 years to 72 years. Prolonged TACT was associated with AF recurrence [MD, 23.12 msec; 95% confidence interval (CI), 11.54-34.71; I2 = 95%]. Subgroup analysis showed that prolonged TACT was strongly associated with AF recurrence in persistent AF cohorts undergoing electrical cardioversion (MD, 26.56; 95% CI, 15.51-37.6; I2 = 86%), while in patients with paroxysmal AF (PAF) undergoing catheter ablation, the results were not statistically significant (MD, 11.48; 95% CI, -1.19 to 24.14; I2 = 90%). The summary area under the curve (sAUC) using a random-effects model was 0.89 (95% CI, 0.80-0.99). TACT is a valuable echocardiographic parameter that can predict AF recurrence in patients following a rhythm-control strategy. Protocol registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022353018.

Left atrial conduction times and regional velocities in persistent atrial fibrillation patients with and without fibrotic atrial cardiomyopathy

Despite the progress in understanding left atrial substrate and arrhythmogenesis, only little is known about conduction characteristics in atrial fibrillation patients with various stages of fibrotic atrial cardiomyopathy (FACM). This study evaluates left atrial conduction times and conduction velocities based on high-density voltage and activation maps in sinus rhythm (CARTO®3 V7) of 53 patients with persistent atrial fibrillation (LVEF 60% (55–60 IQR), LAVI 39 ml/m2 (31–47 IQR), LApa 24 ± 6 cm2). Measurements were made in low voltage areas (LVA ≤ 0.5 mV) and normal voltage areas (NVA ≥ 1.5 mV) at the left atrial anterior and posterior walls. Maps of 28 FACM and 25 no FACM patients were analyzed (19 FACM I/II, 9 FACM III/IV, LVA 14 ± 11 cm2). Left atrial conduction time averaged to 110 ± 24 ms but was shown to be prolonged in FACM (119 ms, + 17%) when compared to no FACM patients (101 ms, p = 0.005). This finding was pronounced in high-grade FACM (III/IV) (133 ms, + 31.2%, p = 0.001). In addition, the LVA extension correlated significantly with the left atrial conduction time (r = 0.56, p = 0.002). Conduction velocities were overall slower in LVA than in NVA (0.6 ± 0.3 vs. 1.3 ± 0.5 m/s, -51%, p < 0.001). Anterior conduction appeared slower than posterior, which was significant in NVA (1 vs. 1.4 m/s, -29%, p < 0.001) but not in LVA (0.6 vs. 0.8 m/s, p = 0.096). FACM has a significant influence on left atrial conduction characteristics in patients with persistent atrial fibrillation. Left atrial conduction time prolongs with the grade of FACM and the quantitative expanse of LVA up to 31%. LVAs show a 51% conduction velocity reduction compared to NVA. Moreover, regional conduction velocity differences are present in the left atrium when comparing anterior to posterior walls. Our data may influence individualized ablation strategies.

Comparison of various tools for diagnosis of an atrial cardiomyopathy for outcome prediction after pulmonary vein isolation in patients with persistent atrial fibrillation - What is the Holy Grail?

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Medtronic Background Atrial cardiomyopathy (ACM) is associated with an increased risk for new-onset atrial fibrillation (AF), progression from paroxysmal to persistent AF-forms and higher arrhythmia recurrence rates after PVI. Therefore, the current ESC guidelines on AF recommend to characterize the underlying ACM to better inform and treat AF patients. Over the past decade, various diagnostic tools were established to diagnose an ACM by analyzing left atrial (LA) structure, and LA electrical and mechanical function. Aim To compare head-to-head electroanatomical mapping (EAM) to assess LA low-voltage substrate (LVS), late gadolinium enhancement (LGE)-MRI to analyse LGE-extent, body surface electrocardiograpghic imaging (ECGI) to measure total atrial conduction time (TACT), digital ECG to analyse amplified p-wave duration (aPWD), and TTE to quantify LA emptying fraction (LA-EF) and LA strain (LAS) regarding ACM diagnosis and outcome prediction after PVI in a homogenous study population. Methods Thirty-six ablation-naive patients (65±9years, 86% male) with persistent AF undergoing PVI were electrically cardioverted prior to PVI and all analyses were performed in sinus rhythm. LGE-MRI, ECGI using a 252-electrode-array, digital ECG and TTE were conducted one day prior to PVI. Subsequently, a high-density LA voltage map (2124±490 sites) was acquired followed by circumferential PVI. MRI-post-processing-analyses were performed by two independent expert laboratories (Marrek for Utah and Adas3D medical for the image-intensity-ratio(IIR)-method). Analysis of aPWD and LAS during reservoir (LASr), conduit (LAScd) and contraction phase (LASct) were performed automatically. Arrhythmia recurrence was recorded within 12 months. Relevant ACM was defined as presence of a LA-LVS≥2cm2 at 0.5mV, a LGE-extent≥20% using the Utah method, a LA-EF&amp;lt;34%, a LASr&amp;lt;23.5%, a LAScd&amp;lt;13.4%, and a LASct&amp;lt;5.4% as described previously. For the IIR-, ECGI-, and automatically measured aPWD-methods, ROC analyses were performed to find the optimal threshold for diagnosis of a relevant ACM as defined in EAM (LA-LVS≥2cm2 at 0.5mV) due to a lack of a predefined threshold. Results A LGE-extent of ≥12% using an IIR cut-off of 1.20, a TACT≥148ms and an automatically measured aPWD≥140ms predicted a relevant ACM as defined in EAM with a sensitivity of 76% and a specificity of 60% for LGE IIR 1.20, a sensitivity of 95% and a specificity of 93% for TACT, and a sensitivity of 86% and a specificity of 80% for aPWD, respectively. Arrhythmia recurrence was significantly higher in patients with a LA-LVS≥2cm2 at 0.5mV, a LGE-extent≥12% at 1.20IIR, a TACT≥148ms, an aPWD≥140ms, a LA-EF&amp;lt;34% and a LASct&amp;lt;5.4%. Conclusion ACM can be diagnosed using EAM, LGE-MRI, ECGI, ECG and TTE and is associated with an increased arrhythmia recurrence rate after PVI. However, only measurement of aPWD in digital ECG, and LA-EF and LAS in TTE are easy, cost-effective, non-invasive methods without any risk for complications.

The effects of combination treatment with LT4 and LT3 on diastolic functions and atrial conduction time in LT4-treated women with low T3: a short term follow-up study.

To investigate the effects of combination treatment with levothyroxine (LT4) and l- triiodothyronine (LT3) on left atrial volume (LAV), diastolic functions, and atrial electro-mechanical delays in LT4-treated women with low triiodothyronine (T3) levels. This prospective study consisted of 47 female patients between 18 and 65 years old treated at an Endocrinology and Metabolism outpatient clinic between February and April 2022 due to primary hypothyroidism. The study included patients with persistently low T3 levels in at least three measurements, despite LT4 treatment (1.6-1.8 mcg/kg/m2) for 23.13 ± 6.28 months with normal thyrotropin (TSH) and free tetraiodothyronine (fT4) levels. The combination therapy dose was as follows: the fixed LT4 dose (25 mcg) was removed from patients' usual LT4 treatment [100 mcg (min-max, 75-150)], and a fixed LT3 dose (12.5 mcg) was added. Biochemical samples were taken, and an echocardiographic assessment was performed for patients upon their first admission, and after 195.5 ± 12.8 days of receiving LT3 (12.5 mcg) treatment. There was a statistically significant reduction at left ventricle (LV) end-systolic diameter (27.69 ± 3.14, 27.13 ± 2.89, p = 0.035), left atrial (LA) maximum volume (14.73 ± 3.22, 13.94 ± 3.15, p = 0.009), LA minimum volume (7.84 ± 2.45, 6.84 ± 2.30, p < 0.001), LA vertical diameter (44.08 ± 6.92, 34.60 ± 4.31, <0.001), LA horizontal diameter (45.65 ± 6.88, 33.43 ± 4.51, p < 0.001), LAVI (50.73 ± 18.62, 41.0 ± 13.02, p < 0.001), total conduction time (103.69 ± 12.70, 79.82 ± 18.40, p < 0.001) after LT3 replacement (respectively pre-post- treatment and p value). In conclusion, the findings of this study suggest that the addition of LT3 to LT4 treatment may lead to improvements in LAVI and atrial conduction times in patients with low T3. However, further research with larger patient groups and exploration of different LT4 + LT3 dose combinations is needed to better understand the effects of combined hypothyroidism treatment on cardiac functions.

Electro-Mechanical Alterations in Atrial Fibrillation: Structural, Electrical, and Functional Correlates.

Atrial fibrillation is the most common arrhythmia encountered in clinical practice affecting both patients' survival and well-being. Apart from aging, many cardiovascular risk factors may cause structural remodeling of the atrial myocardium leading to atrial fibrillation development. Structural remodelling refers to the development of atrial fibrosis, as well as to alterations in atrial size and cellular ultrastructure. The latter includes myolysis, the development of glycogen accumulation, altered Connexin expression, subcellular changes, and sinus rhythm alterations. The structural remodeling of the atrial myocardium is commonly associated with the presence of interatrial block. On the other hand, prolongation of the interatrial conduction time is encountered when atrial pressure is acutely increased. Electrical correlates of conduction disturbances include alterations in P wave parameters, such as partial or advanced interatrial block, alterations in P wave axis, voltage, area, morphology, or abnormal electrophysiological characteristics, such as alterations in bipolar or unipolar voltage mapping, electrogram fractionation, endo-epicardial asynchrony of the atrial wall, or slower cardiac conduction velocity. Functional correlates of conduction disturbances may incorporate alterations in left atrial diameter, volume, or strain. Echocardiography or cardiac magnetic resonance imaging (MRI) is commonly used to assess these parameters. Finally, the echocardiography-derived total atrial conduction time (PA-TDI duration) may reflect both atrial electrical and structural alterations.

Assessment of P Wave Indices in Healthy Standardbred Horses.

P wave indices are used as non-invasive electrocardiographic markers of atrial remodelling in humans. Few studies have investigated their use in animals. The aim of this study was to measure P wave duration and P wave dispersion (Pd) in healthy standardbred horses and investigate variables that might influence these measurements. A 12-lead electrocardiogram was recorded at rest and P wave indices were calculated in 53 horses. A general linear model was used to investigate the main effects: age, bodyweight, sex, resting heart rate, presence of a murmur, exercise status and the number of years raced. There were significant associations with exercise status for both the maximum P wave duration and Pd, with both values being increased in strenuously exercising versus non-active horses. Furthermore, a significant moderate positive correlation was identified between the duration of exercise (number of years raced) and both Pmax and Pd. No other significant associations were identified. These findings are similar to those reported in elite human athletes versus sedentary individuals. The increases in these P wave indices most likely occur due to prolongation and heterogeneity in atrial conduction time, which are associated with structural and electrical remodelling, and may explain the increased risk of atrial fibrillation in athletic horses.

Clinical Electrophysiological Features and Radiofrequency Ablation of Patients with Atrial Fibrillation.

This study aimed to investigate electrophysiological features of radiofrequency ablation surgery in patients with the atrial fibrillation (AF). Fifty patients were included in this study and evenly divided, with 25 AF patients in the experiment group and 25 patients with arrhythmias in the control group. General clinical materials in the two groups were collected. Then, patient number of pulmonary vein antrum potential trial, intra-right atrial conduction time, intra-left atrial conduction time, interatrial conduction time, conduction time between atrium, and pulmonary veins trials were utilized to measure the efficacy of radiofrequency ablation surgery in patients with AF and clarify the relationship between AF and electrophysiological features in the atrium and pulmonary veins. Our study findings showed that conduction time interval between the atrium and pulmonary veins trial by radiofrequency ablation surgery were significantly less than those in pre-treatment AF patients. We can conclude that radiofrequency ablation surgery can effectively treat AF patients by relieving the electrophysiological dysfunction, and radiofrequency ablation can be used to prevent the development of AF.

Assessment of atrial conduction times in patients with frequent premature ventricular complex.

Premature ventricular complex (PVC) is a frequent finding in the general population. The atrial conduction time (ACT) is the period between the electrocardiographic P wave and the atrial mechanical contraction, and its prolongation indicates an atrial electromechanical delay (EMD). In our study, we compared atrial conduction parameters by echocardiographic methods between patients with frequent PVC and healthy control subjects. The study included 54 patients with PVC and 54 healthy volunteers. Atrial conduction parameters were measured with echocardiographic examination. The time difference between the p wave and the Am wave was measured in the septal, lateral, and tricuspid annulus regions. The interatrial EMD, left atrial intra-atrial delay, and the right atrial intra-atrial delay were calculated from these measurements. The groups were compared for demographic and electrocardiographic features and echocardiographic parameters. Left intra-atrial EMD, right intra-atrial EMD, and interatrial EMD were significantly longer in the patient group (p=.001, p < .001, p < .001, respectively). PA lateral, PA septal, and PA tricuspid durations were significantly prolonged in the patient group (all p < .001). All ACT parameters were significantly prolonged in patients with PVC QRS duration of 150 ms and above (all p < .001). All ACT parameters were prolonged in PVCs of right ventricular origin than those of left ventricular origin (all p < .001). ACT parameters were prolonged in patients with a coupling interval time below 485 ms (all p < .001). Atrial conduction times are prolonged in patients with frequent PVC.