Total Atrial Conduction Time Research Articles

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.

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.

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.

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.

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.

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.

Total atrial conduction time provides novel information in prediction for stroke in patients with sinus rhythm

The total atrial conduction time (TACT) measured by echocardiography predicts the risk of atrial fibrillation (AF). This study aimed to investigate whether adding the TACT to the revised Framingham stroke risk profile (rFSRP) improves the efficacy of predicting stroke incidence in patients without prior stroke or known AF. The TACT was measured in 376 consecutive patients > 18 years (58.5 ± 16.3 years; 46% male) receiving echocardiography without any prior history of stroke or AF. The primary endpoint was the occurrence of ischemic stroke, and the secondary endpoint was any documentation of AF during the 2 years of follow-up. During the follow-up period, ischemic strokes occurred in 10 patients (2.65%), and AF in 22 patients (5.85%). The TACT was significantly longer in those who later had a stroke compared with those who did not (169.4 vs. 142.7 ms, p < 0.001). Both rFSRP and TACT predicted the risk for stroke incidence. The univariate model showed that the TACT was a predictor of ischemic stroke incidence (p < 0.001; hazard ratio of 1.94 for every 10 ms; 95% confidence interval, 1.49–2.54). The addition of TACT to rFSRP significantly improved the area under the receiver operating characteristic curve (0.79 vs. 0.85, p = 0.001). Stroke risk prediction was significantly improved by the addition of TACT to rFSRP. The utility of the TACT should be further investigated in large-scale randomized clinical trials.

Prevalence of atrial myopathy among hypertrophic cardiomyopathy patients without atrial fibrillation

Abstract Background Atrial myopathy (AM) is an entity reflecting left atrial (LA) structural and electrical remodeling, connected to atrial fibrillation (AF) development and heart failure progression in various substrates. In hypertrophic cardiomyopathy (HCM), prevalence of AM beyond AF and its correlations are not fully investigated. Purpose Aim of this study was to estimate the prevalence of AM in a cohort of HCM patients without AF history through assessment of LA volume index (LAVI), LA reservoir strain (LARS) and total atrial conduction time (TACT) (estimated by tissue Doppler imaging). Additionally, to investigate AM indices' correlation with other phenotypic and functional characteristics of HCM. Methods We included 50 HCM patients (60±16 years, 80% male, maximum wall thickness 18.6±4.1mm) without history of AF 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 (&amp;gt;5 standard deviations compared to nulled myocardium) in CMR slices. Cut-off points for TACT, LAVI and LARS were adopted by literature (≥115 msec, ≥34 mL/m2 and &amp;lt;21.3% respectively). Results All HCM patients had preserved EF (61.8±8%), while 13 (26%) presented outflow tract obstruction and 4 (8%) diastolic dysfunction stage≥2. LGE was observed in 32 patients (64%) occupying 7.2±5% of left ventricular (LV) mass. Mean TACT was 139.9±22 msec, with LAVI being 30.8±16.1 mL/m2 and LARS 27.6±13.9%. After assessing prevalence of AM parameters, 41 patients (82%) presented a prolonged (≥115 msec) TACT with only 13 of them having also a significantly dilated LA (≥34 mL/m2) and 16 an impaired LARS. 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&amp;lt;0.0005 and r=0.44, p=0.002 respectively, right panels), 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. Conclusions Atrial electro-mechanical delay assessed through TDI based TACT, is the most frequent AM parameter among HCM patients irrespective of AF and even before LA dilatation and LA strain impairment. AM parameters seem to correlate with various morphological and functional characteristics of HCM, their significance, however, in predicting progression towards AF development or HF presentation remains to be elucidated. Funding Acknowledgement Type of funding sources: None.

Effects of Atrial Ischemia on Left Atrial Remodeling in Patients with ST-Segment Elevation Myocardial Infarction

Adverse left atrial (LA) remodeling after ST-segment elevation myocardial infarction (STEMI) has been associated with poor prognosis. Flow impairment in the dominant coronary atrial branch (CAB) may affect large areas of LA myocardium, potentially leading to adverse LA remodeling during follow-up. The aim of this study was to assess echocardiographic LA remodeling in patients with STEMI with impaired coronary flow in the dominant CAB. Of 897 patients with STEMI, 69 patients (mean age, 62±11years; 83% men) with impaired coronary flow in the dominant CAB (defined as Thrombolysis In Myocardial Infarction flow grade < 3) were retrospectively compared with an age- and sex-matched control group of 138 patients with normal dominant CAB coronary flow. Patients with dominant CAB-impaired flow had higher peak troponin T (3.9μg/L [interquartile range, 2.2-8.2μg/L] vs 3.2μg/L [interquartile range, 1.5-5.6μg/L], P=.009). No differences in left ventricular ejection fraction or mitral regurgitation were observed between groups at baseline or at follow-up. LA remodeling assessment included maximum LA volume, speckle-tracking echocardiography-derived LA strain, and total atrial conduction time assessed on Doppler tissue imaging at baseline, 6months, and 12months. Patients with dominant CAB-impaired flow presented larger LA maximal volumes (26.9±10.9 vs 18.1±7.1mL/m2, P<.001) and longer total atrial conduction time (150±23 vs 124±22 msec, P<.001) at 6months, remaining unchanged at 12months. However, all LA strain parameters were significantly lower from baseline (reservoir, 20.3±10.1% vs 27.1±14.5% [P<.001]; conduit, 9.1±5.6% vs 12.8±8% [P<.001]; booster, 9.1±5.6% vs 12.8±8% [P<.001]), these differences being sustained at 6- and 12-month follow-up. Atrial ischemia resulting from impaired coronary flow in the dominant CAB in patients with STEMI is associated with LA adverse anatomic and functional remodeling. Reduced LA strain preceded LA anatomic remodeling in early phases after STEMI.

Echocardiographic Parameters to Predict Atrial Fibrillation in Clinical Routine—The EAHsy-AF Risk Score

BackgroundEchocardiographic parameters representing impaired left atrial (LA) function and remodeling are of high value to predict atrial fibrillation (AF). This study aimed to develop a prediction model for AF easily to apply in clinical routine containing echocardiographic parameters associated with LA remodeling and—function.Methods and ResultsThis monocentric, semi-blinded, controlled analysis included 235 patients to derive a prediction model. This prediction model was tested in a validation cohort encompassing 290 cardiovascular inpatients. The derivation and validation cohort included 54 (23%) and 66 (23%) patients with AF, respectively. Transthoracic echocardiography, comprising parameters indicating left atrial remodeling [septal/lateral total atrial conduction time (s/l PA-TDI)] and left atrial volume indexed to a' (LAVI/a') was performed in each patient. Based on multivariable regressions analysis, four variables were enclosed into the EAHsy (Echocardiography, Age, Hypertension)-AF risk score for AF prediction: Hypertension, Age, LAVI/a‘ and septal PA-TDI. In the validation cohort discrimination was strong (C-statistic 0.987, 95%CI 0.974–0.991) with an adequately performed calibration. The EAHsy-AF risk score was associated with a more precise prediction of AF in comparison to commonly used AF-scores (CHADS2-, ATLAS-, ARIC-, CHARGE-AF score).ConclusionThe EAHsy-AF-Score containing age, hypertension and echocardiographic parameters of atrial dysfunction and remodeling precisely predicts the incidence of AF in a general population of patients with cardiovascular disease. The EAHsy-AF risk score may enable more selective rhythm monitoring in specific patients at high risk for AF.

Total atrial conduction time and its relationship with morphological &amp; functional characteristics in hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Background Total atrial conduction time (TACT), estimated by tissue Doppler imaging (TDI), is an index reflecting left atrial (LA) structural and electrical remodeling, connected to atrial fibrillation (AF) development and heart failure progression in various substrates. In hypertrophic cardiomyopathy (HCM), the significance of TACT beyond AF and its determinants are not fully investigated. Purpose Aim of this study was to estimate TACT in a cohort of HCM patients without AF history and to examine its relationship with other parameters of atrial myopathy, such as LA volume index (LAVI) or LA reservoir strain (LARS). Additionally, to investigate TACT correlation with other phenotypic and functional characteristics of HCM. Methods We included 50 HCM patients (60 ± 16 years, 80% male, maximum wall thickness 18.6 ± 4.1mm) without history of AF who have consecutively undergone 2D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). TACT was measured from the onset P wave on electrocardiogram to the peak A’ wave of the lateral LA wall using TDI (left panel). Burden of fibrosis (percentage of LV mass) was defined by LGE extent (&amp;gt;5 standard deviations compared to nulled myocardium) in CMR slices. Cut-off points for TACT, LAVI and LARS were adopted by literature (≥115 msec, ≥34 mL/m2 and &amp;lt;21.3 % respectively). Results All HCM patients had preserved EF (61.8 ± 8%), while 13 (26%) presented outflow tract obstruction and 4 (8%) diastolic dysfunction stage≥2. LGE was observed in 32 patients (64%) occupying 7.2 ± 5% of left ventricular (LV) mass. Mean TACT was 139.9 ± 22 msec, with LAVI being 30.8 ± 16.1 mL/m2 and LARS 27.6 ± 13.9%. After assessing prevalence of atrial myopathy parameters, 41 patients (82%) presented a prolonged (≥115 msec) TACT with only 13 of them having also a significantly dilated LA (≥34 mL/m2) and 16 an impaired LARS. 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 &amp;lt; 0.0005 and r = 0.44, p = 0.002 respectively, right panels). On the contrary, no significant correlation was established between TACT and traditional diastolic dysfunction indices such as E/E’ or fibrosis extent. Conclusions Atrial electro-mechanical delay assessed through TDI based TACT, is very frequent among HCM patients irrespective of AF and even before LA dilatation and LA strain impairment. Age and hypertrophy magnitude are the main determinants of TACT, the prognostic significance of which remains to be further elucidated. Abstract Figure.

Significance of Left Atrial Electromechanical Function for Atrial Fibrillation Prediction after Cardiac Surgery

Background: Postoperative atrial fibrillation (POAF) is the most important type of secondary AF. POAF is a complication in approximately one-third of patients undergoing cardiac surgery. The duration from P-wave onset on ECG to the peak of the A’ lateral wave on tissue Doppler imaging (PA-TDI) provides a reliable estimation of total atrial conduction time. Objective: To evaluate the efficacy of the PA-TDI duration for predicting post-operative atrial fibrillation in patients undergoing cardiac surgery. Patients and methods: This prospective study was conducted at national heart institute for 70 patients who were eligible and planned for undergoing cardiac surgery. Patients were divided into 2 groups according to the presence of post-operative AF. Accordingly, patients in the study were divided into group (I) that included patients who developed POAF and group (II), which included patients who remained in sinus rhythm and did not develop POAF. Results: PA-TDI duration in group I was longer than in group II with highly significant difference between the two groups with P-value < 0.001. It was found that PA-TDI duration (≥ 171.5 ms) has sensitivity equal to 91 and specificity 95%. Conclusion: PA interval measured by TDI preoperatively seems to be a simple method to predict incidence of POAF in patients undergoing cardiac surgery and it may be part of preoperative cardiovascular examination. The current study suggests that longer PA-TDI duration to be additive to conventional risk factors and biomarkers in predicting POAF and that PA-TDI duration is a predictor of POAF, and the best cut off value of PA-TDI duration for POAF is 171.5 ms.

Non-invasive body surface electrocardiographic imaging for diagnosis of atrial cardiomyopathy.

Atrial cardiomyopathy (ACM) is associated with new-onset atrial fibrillation, arrhythmia recurrence after pulmonary vein isolation (PVI) and increased risk for stroke. At present, diagnosis of ACM is feasible by endocardial contact mapping of left atrial (LA) low-voltage substrate (LVS) or late gadolinium-enhanced magnetic resonance imaging, but their complexity limits a widespread use. The aim of this study was to assess non-invasive body surface electrocardiographic imaging (ECGI) as a novel clinical tool for diagnosis of ACM compared with endocardial mapping. Thirty-nine consecutive patients (66 ± 9 years, 85% male) presenting for their first PVI for persistent atrial fibrillation underwent ECGI in sinus rhythm using a 252-electrode-array mapping system. Subsequently, high-density LA voltage and biatrial activation maps (mean 2090 ± 488 sites) were acquired in sinus rhythm prior to PVI. Freedom from arrhythmia recurrence was assessed within 12 months follow-up. Increased duration of total atrial conduction time (TACT) in ECGI was associated with both increased atrial activation time and extent of LA-LVS in endocardial contact mapping (r = 0.77 and r = 0.66, P < 0.0001 respectively). Atrial cardiomyopathy was found in 23 (59%) patients. A TACT value of 148 ms identified ACM with 91.3% sensitivity and 93.7% specificity. Arrhythmia recurrence occurred in 15 (38%) patients during a follow-up of 389 ± 55 days. Freedom from arrhythmia was significantly higher in patients with a TACT <148 ms compared with patients with a TACT ≥148 ms (82.4% vs. 45.5%, P = 0.019). Analysis of TACT in non-invasive ECGI allows diagnosis of patients with ACM, which is associated with a significantly increased risk for arrhythmia recurrence following PVI.

Yüksek sol atriyal hacim indeksi ve diyastolik disfonksiyonunda sol atriyum fonksiyonel parametrelerindeki değişiklikler

Purpose: Previous studies have shown the relationship between left ventricular diastolic dysfunction (DD) and left atrial volume index (LAVi). However, limited studies have been reported have been reported on the relationship of functional parameters of left atrium (LA) with LAVi and DD. Therefore, we aimed to examine the changes of functional parameters of LA in high LAVi and DD in this study. Materials and methods: Transthoracic echocardiography was performed in 81 healty subjects (LAVi<30 ml/m2) and 81 patients with DD (LAVi>30 ml/m²). Maximum, minimum and preatrial volumes were measured using area-length method. The functional parameters of LA and other parameters including miyocardial performance index (MPI), left ventricular mass index, relative wall thickness, max LAVi/A’, LA sphericity index, the total atrial conduction time (PA-TDI) were calculated and DD was determined by using transmitral and pulmoner ven inflow, pulsed wave Doppler and tissue Doppler. Results: Initially; max LAVi, min LAVi, preA LAVi, max LAVi/A’, LA sphericity index, LA total emptying volume (EV) index, LA active EV index, LA passive EV index, PA-TDI, left ventricular relative wall thickness, left ventricular mass index and MPI were significantly higher in patients with DD and high LAVi (p<0.05). The groups had similar total LA emptying fraction (LAEF) when age difference was removed with Ancova test analysis. LA expansion index decreased with age in patients with DD and high LAVi in correlation analysis (r=-0.408, p<0.001). Conclusion: Max LAVi, min LAVi, preA LAVi, max LAVi/A’, LA sphericity index, LA total EV index, LA active EV index, LA passive EV index, PA-TDI, relative wall thickness, left ventricular mass index and MPI were higher in DD and high LAVi regardless of age. Although LA expansion index and total LAEF did not show significant alterations until 57 years in healthy subjects in this study, both of them may decrease in patients with DD and high LAVi, especially in advanced ages, due to prolonged exposure to high filling pressure of left ventricle.

Predictors of left atrial remodeling in newly diagnosed hypertensive patients: a speckle-tracking echocardiographic study.

Endothelial dysfunction, oxidative stress, and increased inflammatory activity are the main pathophysiological mechanisms responsible for cardiac remodeling secondary to hypertension. Bilirubin has anti-oxidant, anti-inflammatory, and anti-fibrotic functions. This report's objectives are to determine whether Query identifiers of left atrial (LA) remodeling, total atrial conduction time (TACT) and LA reservoir strain (LARS), are associated with serum total bilirubin levels, and to identify the possible predictors of LA remodeling in newly diagnosed hypertensive subjects. One hundred thirty-four subjects were enrolled in this study. TACT was evaluated by tissue Doppler imaging, and LARS was calculated by speckle-tracking echocardiography. Laboratory parameters were recorded. The subjects were classified into two separate groups according to the median value of TACT and LARS. In patients with supramedian TACT, LA volume index (LAVI) and epicardial adipose tissue (EAT) thickness were higher, while LARS and LVGLS were lower. In subjects with inframedian LARS, TACT was longer, LAVI and EAT thickness were higher, and LVGLS was lower. Patients with supramedian TACT and inframedian LARS were older and had lower total bilirubin. Total bilirubin, EAT thickness, and age were predictors of TACT and LARS. Serum bilirubin levels may have a protective effect on the LA remodeling process in newly diagnosed hypertensive subjects.

Role of pre-operative transthoracic echocardiography in predicting post-operative atrial fibrillation after cardiac surgery: a systematic review of the literature and meta-analysis.

This systematic review and meta-analysis aims to evaluate the role of pre-operative transthoracic echocardiography in predicting post-operative atrial fibrillation (POAF) after cardiac surgery. Electronic databases were searched for studies reporting on pre-operative echocardiographic predictors of POAF in PubMed, Cochrane library, and Embase. A meta-analysis of echocardiographic predictors of POAF that were identified by at least five different publications was performed. Forty-three publications were included in this systematic review. Echocardiographic predictors for POAF included surrogate parameters for total atrial conduction time (TACT), structural cardiac changes, and functional disturbances. Meta-analysis showed that prolonged pre-operative PA-TDI interval [5 studies, Cohen's d = 1.4, 95% confidence interval (CI) 0.9-1.9], increased left atrial volume indexed for body surface area (LAVI) (23 studies, Cohen's d = 0.8, 95% CI 0.6-1.0), and reduced peak atrial longitudinal strain (PALS) (5 studies, Cohen's d = 1.4, 95% CI 1.0-1.8), were associated with POAF incidence. Left atrial volume indexed for body surface was the most important predicting factor in patients without a history of AF. These parameters remained important predictors of POAF in heterogeneous populations with variable age and comorbidities such as coronary artery disease and valvular disease. This meta-analysis shows that increased TACT, increased LAVI, and reduced PALS are valuable parameters for predicting POAF in the early post-operative phase in a large variety of patients.

Total atrial conduction time as a possible predictor of atrial fibrillation recurrence after catheter ablation for paroxysmal atrial fibrillation: relationship between electrical atrial remodeling and structural atrial remodeling time courses.

Recently, the estimated total atrial conduction time measured using tissue Doppler imaging (PA-TDI duration) has been reported as a more accurate predictor of atrial fibrillation (AF) recurrence after catheter ablation than left atrial volume index (LAVI). The PA-TDI duration is considered to reflect electrical and structural remodeling in the right atrium (RA) and left atrium (LA). We sought to investigate the association between AF recurrence and PA-TDI duration after AF ablation. We studied 209 patients who underwent radiofrequency ablation for paroxysmal AF and 75 patients who underwent second ablation for AF recurrence. We assessed the duration from the onset of the P wave on the surface electrocardiogram to the atrial electrogram in distal coronary sinus (CS) (PA-CSd duration) indicating electrical remodeling of the atrium, the PA-CS proximal duration (PA-CSp duration) representing electrical remodeling of RA, and the conduction time in CS (proximal to distal) (CSp-CSd duration) reflecting electrical remodeling of LA. We also measured LAVI as a marker of structural remodeling of LA. The PA-TDI duration had a positive correlation with PA-CSd duration. In the patients with AF recurrence, PA-TDI duration, PA-CSd duration, and CSp-CSd duration in the second ablation were significantly longer than those in the first (p < 0.01, respectively), whereas there was no significant difference in LAVI and PA-CSp duration between the first and second ablation sessions. A prolonged PA-TDI duration after AF ablation may indicate advanced electrical remodeling of LA, and may predict AF recurrence after ablation in patients with paroxysmal AF.

The Effects of Laparoscopic Sleeve Gastrectomy on Cardiac Diastolic Function, Aortic Elasticity, and Atrial Electromechanics Delay.

Obesity is a well-known risk factor for cardiovascular diseases. The aim of this study was to prospectively investigate the short-term effects of laparoscopic sleeve gastrectomy (LSG) on cardiac functions. Forty-four morbidly obese patients who underwent LSG were included in the study. The aortic systolic and diastolic diameters, left ventricular (LV) diameter, LV cardiac output and cardiac index, LV ejection fraction, LV septal and lateral wall velocities, deceleration time of the E wave, the LA volume index and atrial mechanic functions, and atrial conduction times were evaluated. The patients' aortic stiffness index showed a significant improvement at postoperative control: 3.23 ± 0.58, 2.49 ± 0.36; p<0.001 for preoperative and postoperative aortic stiffness index, respectively. A significant reduction was observed in the LV mass and relative wall thickness (RWT) of the patients: 182.41 ± 36.87 g, 154.85 ± 24.32 g; p<0.001 and 0.42 ± 0.07, 0.39 ± 0.05; p=0.010 for the preoperative and postoperative LV mass and RWT, respectively. A statistically significant decrease was observed in total atrial conduction time and interatrial and intraatrial conduction time in the postoperative period: 120.95 ± 22.27 ms, 106.57 ± 20.46 ms; p=0.001; 13.82 ± 8.21 ms, 10.66 ± 6.78 ms; p=0.038, and 29.64 ± 14.18 ms, 24.09 ± 10.95 ms; p=0.047 for preoperative and postoperative total atrial conduction time, intraatrial electromechanical delay, and interatrial electromechanical delay, respectively. Weight loss reduced aortic stiffness, IVS and posterior wall thickness, LAV, LAVi, LA passive emptying fraction, and atrial electromechanical delays in morbidly obese patients.