Abstract 12541: Left Atrial Cardiomyopathy and Associations With Left Atrial Structure and Function

Left atrial (LA) myopathy, characterized by LA enlargement and mechanical dysfunction, is associated with worse prognosis in hypertrophic cardiomyopathy (HCM) while the impact of sarcomere mutation on LA myopathy remains unclear. We aimed to assess the association between LA myopathy and sarcomere mutation and to explore the incremental utility of LA strain in mutation prediction. A total of 105 consecutive HCM patients (mean age 47.8 ± 11.9years, 71% male) who underwent HCM-related gene screening and cardiac MRI were retrospectively enrolled. LA volume, ejection fraction and strain indices in reservoir, conduit, and booster-pump phases were investigated respectively. Fifty mutation-positive patients showed higher LA maximal volume index (59.4 ± 28.2 vs 43.8 ± 18.1mL/m2, p = 0.001), lower reservoir (21.3 ± 7.9 vs 26.2 ± 6.6%, p < 0.001), and booster-pump strain (12.1 ± 5.4 vs 17.1 ± 5.0%, p < 0.001) but similar conduit strain (9.2 ± 4.5 vs 9.1 ± 4.5%, p = 0.909) compared with mutation-negative patients. In multivariate logistic regression, LA booster-pump strain was associated with sarcomere mutation (odds ratio = 0.86, 95% confidence interval: 0.77-0.96, p = 0.010) independent of maximal wall thickness, late gadolinium enhancement, and LA volume. Furthermore, LA booster-pump strain showed incremental value for mutation prediction added to Mayo II score (AUC 0.798 vs 0.709, p = 0.024). In HCM, mutation-positive patients suffered worse LA enlargement and worse reservoir and booster-pump functions. LA booster-pump strain was a strong factor for sarcomere mutation prediction added to Mayo II score. The independent association between sarcomere mutation and left atrial mechanical dysfunction provide new insights into the pathogenesis of atrial myopathy and is helpful to understand the adverse prognosis regarding atrial fibrillation and stroke in mutation-positive patients. • In patients with hypertrophic cardiomyopathy, left atrial (LA) reservoir and booster-pump function, but not conduit function, were significantly impaired in mutation-positive patients compared with mutation-negative patients. • LA booster-pump strain measured by MRI-derived feature tracking is feasible to predict sarcomere mutation with high incremental value added to Mayo II score.

Background: Abnormal P-wave terminal force in lead V1 (PTF-V1) is an ECG marker of increased left atrial (LA) volume, elevated LA filling pressures and/or LA systolic dysfunction. Because left ventricular (LV) diastolic dysfunction is one of the potential mechanisms driving LA remodelling, we hypothesized that PTF-V1 might be an additional ECG marker of diastolic dysfunction.Methods: LV diastolic function after 3 years’ systematic antihypertensive treatment was examined in relation to baseline PTF-V1 in 431 hypertensive patients undergoing protocol-driven blood pressure reduction who had baseline and year-3 ECG and echocardiographic data and a preserved LV ejection fraction (EF >45%) at year-3. Abnormal diastolic function was defined by the tenth or 90th percentile values from 405 normotensive, non-obese and non-diabetic adults without overt cardiovascular disease. Abnormal PTF-V1, defined by the presence of a negative terminal P-wave in lead V1 ≥ 4000 μV·ms, was present in 167 patients (38.7%).Results: Abnormal PTF-V1 was associated with worse year-3 mean diastolic first third filling time (0.43 ± 0.08 vs 0.40 ± 0.07 sec, p = 0.039), first half filling time (0.55 ± 0.07 vs 0.53 ± 0.07 sec, p = 0.041), mitral valve A velocity (86 ± 27 vs 76 ± 19 cm/sec, p = 0.009) and mitral valve E/A ratio (0.85 ± 0.22 vs 0.94 ± 0.27, p = 0.007) after adjusting for other potential predictors of diastolic dysfunction including race, and heart rate, systolic blood pressure and severity of ECG LVH by Cornell product criteria at baseline. In parallel multivariate logistic regression analysis, abnormal PTF-V1 was associated with significantly increased odds of abnormal mitral valve E/A ratio (OR 1.55, 95%CI 1.04–2.32 p = 0.032), and a trend toward higher odds of abnormal half filling time (OR 1.42, 95%CI 0.94–2.15, p = 0.098) at year-3 of follow-up.Conclusions: Abnormal P-wave terminal force in lead V1 is associated with worse diastolic function and predicts abnormal LV diastolic behaviour in patients with preserved EF after 3 years of blood pressure reductive therapy.

Funding AcknowledgementsType of funding sources: None.BackgroundPrevious data suggested that left atrial (LA) function may be impaired by extensive atrial fibrillation (AF) ablation. Ethanol infusion of Vein of Marshall (EI-VOM) as an adjunctive therapy to pulmonary vein isolation is an emerging therapeutic strategy that has shown to improve efficacy in persistent AF ablation procedures and mitral isthmus line. The impact of EI-VOM scar formation on LA function has not been addressed.PurposeTo analyse the effect of EI-VOM on LA function, evaluated by magnetic resonance imaging (MRI) strain parameters.MethodsTwelve patients referred for de novo persistent AF or any repeat procedure were included. MRI was performed previous (baseline) and 3-month after AF ablation. MRI images were analyzed off-line with specialized post-processing software. LA volumes, LA strain parameters, including LA global longitudinal strain (GLS), LA reservoir (LASr), conduit (LAScd) and contractile (LASct) strain; LA ejection fraction (LAEF), LA passive emptying function (LAPEF) and LA active emptying function (LAAEF) were measured from SSFPs two-chamber cine sequences.ResultsTwo patients were excluded due to absence of VOM and failed ethanolization. Ten patients (83%) underwent both MRI studies (64 [55-71]years; 80% men; de novo ablation of persistent AF (50%)). Six patients received additional mitral isthmus line and three posterior wall isolation. Mean baseline indexed LA volume was 62.7ml/m2 [47-73]. Baseline LA strain and EF parameters were: LA GLS 17.16±15.3, LASr 17.80±14.9%, LAScd -5.96±3.7%, LASct -10.35±9.5%; LAPEF 5.89±9.8, LAAEF 23.87±17.0 and LAEF 27.6±18.3%. At 3-months follow-up, no AF recurrences were detected. No differences were found regarding LA volume (57.6ml/m2 [42-64], p=0.671), strain parameters (LA GLS Δ0.62, p=0.903; LASr Δ0.02, p=0.991; LAScd Δ-0.84, p=0.563; LASct Δ0.54, p= 0.874) and LAEF parameters (LAPEF Δ4.82, p=0.592; LAAEF Δ3.03, p=0.903; and LAEF Δ7.0, p=0.213).ConclusionsEI-VOM appears as a safe adjunctive strategy in AF ablation in terms of LA function. The present study did not show impairment in the main MRI strain parameters.Baseline vs. post-ablation LA GLS

Left atrial (LA) volume is a well-established cardiovascular prognosticator in patients with end-stage renal disease. Although dialysis intensification is associated with left ventricular mass regression, there are limited data regarding LA remodeling. Using cardiac magnetic resonance imaging (CMR), we examined changes in LA size and function relative to ventricular remodeling and cardiac biomarkers after dialysis intensification. In this prospective 2-centre cohort study, 37 patients receiving conventional hemodialysis (CHD, 4h/session, 3×/week) were converted to in-centre nocturnal hemodialysis (INHD 7-8h/session, 3×/week); 30 patients remained on CHD. CMR and biomarkers were performed at baseline and repeated at 52 weeks. After 52 weeks, there were no significant changes in the LA volumes or LA ejection fraction (EF) within either the CHD or INHD group, and no significant differences between the two groups. Correlations existed between changes in LA and LV end-diastolic volume index (EDVi, Spearman's r = 0.69, p < 0.001), LA and LV end-systolic volume index (ESVi, r = 0.44, p = 0.001), LAEF and LVEF (r = 0.28, p = 0.04), LA and RV EDVi (r = 0.51, p < 0.001), LA and RV ESVi (r = 0.29, p = 0.039), and LA ESVi and LV mass index (r = 0.31, p = 0.02). At baseline, indexed LA volumes positively correlated with NT-proBNP, whereas LAEF negatively correlated with NT-proBNP and Troponin I. After 52 weeks, changes in biomarker levels did not correlate with changes in LA volume or EF. There was no significant change in LA size or systolic function after conversion to INHD. The significant correlations between LA and ventricular remodeling and cardiac biomarkers suggest common underlying pathophysiologic mechanisms. ClinicalTrials.gov Identifier: NCT00718848.

Risk in atrial fibrillation: left atrial function matters

Funding Acknowledgements Vestre Viken Hospital Trust Background Left atrial (LA) enlargement is associated with elevated blood pressure (BP) and with cardiovascular morbidity and mortality. In the assessment of LA size, echocardiographic guidelines recommend the use of LA end-systolic volume (LAVmax). LA end-diastolic volume (LAVmin) and LA emptying fraction (LAEF) may add valuable information in risk assessment. The knowledge of early adulthood BP and its association to LA volumes and LAEF later in life is limited. Purpose To explore the association between systolic BP at age 40 and LA volumes and LAEF at age 64. Methods We linked data from subjects who had participated in both a nationwide cardiovascular screening survey (1990-1991) at the age of 40, and the Akershus Cardiac Examination (ACE) 1950 Study (2012-2015) at the age of 64 (n = 2,597). In the ACE 1950 Study, LAVmax and LAVmin were measured with echocardiography according to the summation of discs method. LAEF was calculated as (LAVmax-LAVmin/LAVmax)x100%. The association between systolic BP at age 40 and LA volumes and LAEF at age 64 was assessed in univariate and multivariate linear regression analyses. Results Systolic BP at age 40 was associated with LAVmax and LAVmin but not with LAEF at age 64. In our multivariate model, a 10 mm Hg higher systolic BP at age 40 was associated with a 0.9 ml greater LA end-systolic volume and a 0.5 ml greater LA end-diastolic volume at age 64. Conclusion Early adulthood systolic BP is associated with LA volumes 24 years later in life. Table. Association of systolic blood pressure at age 40 to left atrial (LA) volumes and LAEF at age 64 Univariate Multivariate* Dependent variable B (95% CI) p-value B (95% CI) p-value LAVmax (ml) 2.4 (2.0, 2.9) &amp;lt;0.001 0.9 (0.4, 1.4) 0.001 LAVmin (ml) 1.5 (1.1, 1.8) &amp;lt;0.001 0.5 (0.1, 0.9) 0.015 LAEF (%) -0.01 (-0.3, 0.3) 0.938 0.2 (-0.2, 0.5) 0.294 *Adjusted for gender, body mass index, smoking, resting heart rate and antihypertensive treatment, all assessed at age 40. B (95% CI), regression coefficient for systolic blood pressure (per 10 mm Hg) with 95% confidence interval; LAVmax, LA end-systolic volume; LAVmin LA end-diastolic volume; LAEF, LA emptying fraction

Objective Changes in left atrial (LA) size and function are associated with major adverse cardiovascular outcomes such as atrial fibrillation, heart failure, stroke, and death. Reverse LA remodelling occurs after successful surgical mitral valve repair for severe MR. Changes in LA volumes after MV repair have reported in several studies. However, LA data are limited in the setting of transcatheter repair. Materials an methods From November 2016 to July 2018, clinical and echocardiographic data of 42 patients with mitral regurgitation who underwent Mitraclip implantation in our division were evaluated for LA function: LA global longitudinal strain (LA GLS); LAESV (Left atrial end-systolic volume), LAEDV (Left atrial end-diastolic volume); LA emptying Fraction at baseline, at 1 month, at 6 months and 1 year of follow up were assessed. The variation of continuous variables was evaluated using a student T test for paired data or the Wilcoxon matched-pair signed rank test when appropriate. The categorical variables between two groups were evaluated using the chi-square test (χ2). P values &amp;lt;0.05 were considered significant. Results The etiology of the mitral regurgitation was primary in 33,3% and secondary in 66,7% of the included patients. The MR degree was 3+ in 21,4% of patients and 4+ in 78,6%. When compared to baseline at 6 months and 1 year a statistically significant reduction was observed for both LAESV (p&amp;lt;0.001) and LAEDV (p&amp;lt;0.001). At 6 months, compared to baseline, the LA GLS reached statistic relevance (p 0.05) with a significant improvement at 1 year (p 0.001). Finally, we did not find significant differences in LA emptying fraction at different time point analyzed. Conclusions A successful MitraClip procedure can reverse the process of LA remodeling within 12 months, and this can be detected by Two-dimensional speckle tracking echocardiography (2D STE) through an improvement in the LA reservoir function. These data generate the hypothesis that the GLS, compared to conventional echocardiographic parameters, represents an advanced method that quantify atrial function in Mitraclip implanted patients. Funding Acknowledgement Type of funding source: Public hospital(s)

Atrial function, atrial volume and cardiovascular clinical outcomes in patients with end-stage renal disease – A study of cardiac computed tomography

Funding Acknowledgements Vestre Viken Hospital Trust Background Left atrial (LA) enlargement is associated with cardiovascular morbidity and mortality. Echocardiographic guidelines recommend body surface area (BSA) indexed LA end-systolic volume (LAVimax) in the assessment of LA size with an upper normal limit of 34 ml/m² for both genders and all age groups. LA end-diastolic volume (LAVimin) and LA emptying fraction (LAEF) may add valuable information in risk assessment, but there are limited data on normal values. Purpose To add knowledge and explore gender differences of LA volumetric measures. Methods In The Akershus Cardiac Examination 1950 Study, all inhabitants of Akershus County, Norway, born in 1950 were invited. In 3,489 individuals LAVmax and LAVmin were measured with echocardiography according to the summation of discs method and indexed to BSA. LAEF was calculated. A healthy group was defined by excluding those with heart failure, atrial fibrillation, coronary artery disease, stroke, hypertension, diabetes, chronic obstructive pulmonary disease, body mass index &amp;gt; 30kg/m², eGFR &amp;lt; 60 ml/min/1.73 m², left ventricular ejection fraction &amp;lt; 50%, E/e’&amp;gt;14 and E/A &amp;gt; 2.0. Data are presented as mean ± standard deviation (SD) and a normal range of mean ± 2SD. T-tests were used for comparisons. Results In 840 healthy individuals, aged 63.8 ± 0.6 years, mean LAVimax was 25.6 ± 6.3 ml/m² and the normal range was 13.0-38.2 ml/m². Men had significantly larger volumes than women. Conclusion We present LA volumes and LAEF in a large cohort from the general population at age 64. The upper normal limit of LAVimax in 840 healthy individuals was 38 ml/m². Men had larger LA volumes than women, contrary to most previous studies. Thus, 13% of the healthy men in our cohort would be defined with an enlarged atrium with the current cut-off value at 34 ml/m². Table. Left atrial (LA) volumes and LAEF Total (mean ± SD) Total (2SD range) Male (mean ± SD) Female (mean ± SD) P-value (male vs. female) All participants (n = 3489) LAVimax (ml/m&amp;sup2;) 26.8 ± 7.6 11.6-42.0 27.9 ± 8.1 25.6 ± 6.8 &amp;lt;0.001 LAVimin (ml/m&amp;sup2;) 14.7 ± 5.8 3.1-26.3 15.5 ± 6.5 13.9 ± 4.9 &amp;lt;0.001 LAEF (%) 45.6 ± 9.7 26.2-65.0 45.3 ± 10.2 45.9 ± 9.2 0.07 Healthy group (n = 840) LAVimax (ml/m&amp;sup2;) 25.6 ± 6.3 13.0-38.2 26.6 ± 6.7 24.9 ± 5.8 &amp;lt;0.001 LAVimin (ml/m&amp;sup2;) 13.7 ± 4.3 5.1-22.3 14.1 ± 4.6 13.3 ± 3.9 0.008 LAEF (%) 46.8 ± 8.8 29.2-64.4 47.0 ± 9.1 46.5 ± 8.4 0.37 LAVimax, LA end-systolic volume, body surface area (BSA)-indexed; LAVimin, LA end-diastolic volume, BSA-indexed; LAEF, LA emptying fraction; SD, standard deviation

Left Atrial Function Predicts Heart Failure Hospitalization in Subjects With Preserved Ejection Fraction and Coronary Heart Disease: Longitudinal Data From the Heart and Soul Study

Late gadolinium enhancement (LGE) cardiac magnetic resonance imaging (MRI) studies were performed on healthy individuals to establish signal intensity thresholds for reproducible left atrial (LA) patchy LGE detection. Using established criteria, differences in LA patchy LGE between healthy volunteers (HV) and patients with atrial fibrillation (AF) or hypertension were analyzed. Fifty-three patents with AF (mean age 56 years, 60% men), 25 patients with hypertension and no history of AF (mean age 54 years, 40% men), and 28 HV (mean age 50 years, 52% men) were enrolled in an observational, non-interventional, case-control prospective study. LA patchy LGE quantification was performed using LGE MRI (1.5 T scanner, voxel size 1.25x1.25x2.5 mm) and the custom-built software based on estimation of LA voxel image intensity ratio and comparison with threshold value obtained from HV data. Based on analysis of healthy individuals' data, the optimal threshold value for the left atrial patchy LGE quantification was determined at 1.38. Patients with AF had a higher extent of LA patchy LGE (9.1 [1.72; 18.58] %) than patients with hypertension (3.81 [0.57; 9.51] %) and HV (0.78 [0.05; 3.5] %). The predominant location of LA patchy LGE in AF was in the pulmonary vein ostia region, in hypertension - LA posterior wall, and in HV - lower part of LA posterior wall. In AF patients, the extent of LA patchy LGE correlated with LA end-diastolic volume (r=0.37) and LA ejection fraction (r=-0.4), in HV - with age (r=0.66) and LA end-diastolic volume (r=0.4). AF and hypertension are associated with higher extent and different location of LA patchy LGE compared to changes caused by natural aging. The extent of LA patchy enhancement correlates with LA dilatation.

Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): ReForM-B-Program Background Abnormal P-wave terminal force in lead V1 (PTFV1) is associated with atrial remodeling. The relationship between PTFV1 and atrial function after acute myocardial injury is insufficiently understood and may be elucidated by detailed feature tracking (FT) strain analysis of cardiac magnetic resonance images (CMR). Purpose We investigated the relationship between PTFV1 and left atrial (LA) strain (measured by CMR) in a patient cohort presenting with acute myocardial infarction (MI). Methods 56 patients with acute MI underwent CMR within 3-5 days after MI. PTFV1 was measured as the product of negative P-wave amplitude and duration in lead V1 (Fig. A). A PTFV1 &amp;gt;4000 ms*µV was defined as abnormal. CMR cine data were retrospectively analyzed using a dedicated FT software. LA strain (ε) and strain rate (SR) for atrial reservoir ([εs]; [SRs]), conduit ([εe]; [SRe]) and booster function ([εa]; [SRa]) were measured in two long-axis views (Fig. A). Results Patients with abnormal PTFV1 had significantly reduced LA conduit function εe and SRe (Fig. B + D). There was a significant negative correlation between the extent of PTFV1 and both εe and SRe (Fig. C + E). In univariate and multivariate regression models, both PTFV1 and age predicted atrial conduit function. In contrast, multiple clinical co-factors had no significant influence on εe (Table). Interestingly, linear regression models revealed only mild dependency of PTFV1 on conventional parameters of cardiac function such as left ventricular ejection fraction (p = 0.059; R²(adj.)=0.047), and no dependency on structural parameters such as LA area (p = 0.639; R²(adj.)=0.016), or LA fractional area change (p = 0.825; R²(adj.)=0.020). Conclusion Abnormal PTFV1 was associated with reduced LA function independent from numerous clinical co-factors in patients presenting with acute myocardial infarction. Table N = 56 Linear Regression Analysis Multiple Linear Regression Analysis (R2 (adj.)=0.376, p = 0.016) Variable B 95% CI P value R2 (adj.) B 95% CI P value PTFV1 [µV*ms] -1.628 17085.298 to 27210.854 0.013 0.092 -1.315 -2.614 to -0.016 0.047 Age [y] -425.775 24985.168 to 54634.995 0.002 0.145 -610.815 -982.78 to -238.849 0.001 Body mass indes [kg/m2] -185.653 -3259.187 to 47020.775 0.671 -0.015 -506.096 -1327.357 to 315.165 0.219 Creatinine kinase [U/l] -1.571 14806.991 to 24842.272 0.121 0.027 -1.791 -3.72 to 0.138 0.067 Male sex -893.28 10701.206 to 23504.066 0.802 -0.017 4275.631 -3842.517 to 12393.78 0.292 Estimated glomerular filtration rate [ml/min/1.73m2] 88.617 -4564.177 to 21395.361 0.202 0.012 -163.981 -331.343 to 3.381 0.054 Systolic blood pressure [mmHg] -2.001 14045.786 to 22037.253 0.095 0.038 29.331 -108.243 to 166.906 0.668 nt-pro brain natriuretic peptide [pg/ml] 24.629 -4060.804 to 30920.828 0.716 -0.016 1.015 -1.778 to 3.809 0.466 Univariate and multivariate linear regression models for left atrial conduit strain Abstract Figure

IntroductionGrowing evidence implicates atrial cardiopathy (AC) as a causative factor for embolic strokes of undetermined source (ESUS), a distinct subtype of cryptogenic stroke (CS). AC however is poorly defined, with...

Left Atrial Myopathy and Atrial Arrhythmia Recurrence After Pulmonary Vein Isolation in Patients With Minimal Left Atrial Low Voltage Areas.

Relation of Electrocardiographic Left Atrial Abnormalities to Risk of Stroke in Patients with Atrial Fibrillation