Larger Left Atrial Volume Research Articles

Left atrial total emptying fraction measured by cardiovascular magnetic resonance imaging predicts low-voltage areas detected during electroanatomical mapping.

Low-voltage areas (LVAs) found during left atrial (LA) electroanatomical mapping are increasingly targeted by radiofrequency catheter ablation (RFCA) on top of pulmonary vein isolation to improve arrhythmia-free survival in patients with atrial fibrillation (AF). However, pre-procedural prediction of LVAs remains challenging. The purpose of the present study was to describe the association between parameters of LA function and dimensions, respectively, derived from pre-procedural cardiovascular magnetic resonance (CMR) imaging, and the presence of LVAs on LA voltage mapping. Patients who underwent first-time RFCA for paroxysmal or persistent AF and who were in stable sinus rhythm during pre-procedural CMR imaging were included in this study. Cardiovascular magnetic resonance-derived parameters of LA function and dimensions were calculated. Low-voltage areas were defined as areas with bipolar voltage amplitudes of ≤0.5 mV on electroanatomical mapping. In total, 259 consecutive patients were included in this analysis. Low-voltage areas were found in 25 of 259 patients (9.7%). Compared with those without LVAs, patients with LVAs were significantly older, were more likely to be female, had a higher CHA2DS2-VASc score, had larger LA volumes, and had a lower LA total emptying fraction (TEF). In multivariate analysis, only LA TEF [odds ratio (OR) 0.885, 95% confidence interval (CI) 0.846-0.926, P < 0.001] and the CHA2DS2-VASc score (OR 1.507, 95% CI 1.115-2.038, P = 0.008) remained independently associated with the presence of LVAs. Left atrial TEF and the CHA2DS2-VASc score were independently associated with the presence of LVAs found during LA electroanatomical mapping. These findings may help to improve pre-procedural prediction of pro-arrhythmogenic LVAs and to improve peri-procedural patient management.

Clinical effectiveness and efficiency of a new steerable sheath technology for radiofrequency ablation in Chinese patients with atrial fibrillation: a retrospective comparative cohort study.

The clinical effectiveness and efficiency of a steerable sheath for radiofrequency catheter ablation (RFCA) in Chinese patients with atrial fibrillation (AF) needs to be compared with a fixed curve sheath to optimize RFCA procedure. This retrospective study included adult AF patients with their first RFCA that was conducted by the same electrophysiologist using a steerable sheath (VIZIGO, Biosense Webster, Inc.) or a fixed curve sheath (NaviEase, Synaptic Medical) in a Chinese tertiary care hospital from January to November 2021. The medical records kept at the hospital were the source of study data that included patient baseline characteristics and outcome measures for the clinical effectiveness and efficiency of RFCA procedure. Multivariate generalized linear regression analyses were performed to explore the impact of sheath type on clinical effectiveness and efficiency after adjustment. Fourteen patients using steerable sheath and 34 patients using fixed curve sheath for RFCA were included in the data analysis. Most of patient baseline characteristics associated with the two study groups were comparable except that the steerable sheath group had significantly higher left atrium diameter (41.9±6.5 vs. 38.1±3.9 mm, P=0.017) and larger left atrium volume (150.4±29.5 vs. 126.8±27.5 mL, P=0.017) than the fixed curve sheath group. Using steerable sheath was associated with significantly shorter total pulmonary vein isolation (PVI) fluoroscopy time and post-surgery hospital length of stay (LOS) than using fixed curve sheath in both unadjusted comparisons (PVI fluoroscopy time: 1.3±1.5 vs. 4.0±3.9 min, P=0.004; post-surgery LOS: 2.1±0.7 vs. 2.9±1.5 days, P=0.034) and multivariate generalized regression analyses (PVI fluoroscopy time: coefficient =-0.859, P=0.014; post-surgery LOS: coefficient =-0.303, P=0.018). Compared to fixed curve sheath, steerable sheath used for RFAC could have the potential to shorten the PVI fluoroscopy time and reduce post-surgery LOS in a Chinese real-world hospital setting. Future real-world studies with large sample size are needed to confirm our study findings.

The correlation of left atrial dysfunction and amyloid load in patients with immunoglobulin light-chain cardiac amyloidosis: a 3T cardiac magnetic resonance study.

To investigate the left atrial (LA) changes in immunoglobulin light-chain cardiac amyloidosis (AL-CA) patients with different risk stratifications and to explore the correlation between LA function and the degree of amyloid load using cardiac magnetic resonance (CMR) imaging. Forty-three AL-CA patients were retrospectively enrolled and were divided into low-to-moderate-risk group (n = 16, increased NT-proBNP or troponin I, or both normal) and high-risk group (n = 27, increased NT-proBNP and troponin I). 20 healthy individuals matched for age and gender were included. The function, myocardial deformation of left heart, and left ventricular (LV) tissue characterization among the three groups were compared. The correlation between LA function and LV tissue characterization was investigated. Compared with the controls, the AL-CA patients had a larger LA volume, lower left atrial emptying fraction (LAEF) and impaired left atrial strain (LAS). The high-risk group exhibited lower reservoir and booster function and increased LV extracellular volume (LV-ECV) than the low-to-moderate-risk group (p < 0.05). LV-ECV was significantly correlated with LAS and LAEF (all p < 0.05) but not LAEFconduit. The LAS and LAEF had a good diagnostic ability for risk stratification of AL-CA patients (area under the curve, 0.70 ~ 0.72). High-risk AL-CA patients showed more severe LA function impairment than low-to-moderate-risk AL-CA patients. LAS and LAEF were closely associated with LV-ECV in AL-CA patients, LAS and LAEF exhibited good capability to differentiate AL-CA patients of different risk stratifications. CMR-derived LAS and LAEF were correlated with amyloid load, allowing for differentiation of AL-CA patients at different risk stages.

Left ventricular hypertrophy, dilatation and ejection fractions predict ventricular tachycardia in amyloid transthyretin cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Pfizer Global Medical Grant Background Amyloid transthyretin cardiomyopathy (ATTR-CM) is a progressive infiltrative cardiomyopathy caused by extracellular deposition of amyloid fibrils. The disease is characterized by congestive heart failure, conduction abnormalities and arrhythmias. Due to the limited overall prognosis, ICDs were rarely indicated in ATTR-CM. However, with the development of new targeted therapies, the role of ICD therapy for ATTR-CM should be reevaluated. Hence, there is an urgent and unmet need to identify patients at high risk for ventricular tachycardias who might possibly benefit from ICD therapy. Methods Between 2020 and 2022, 120 patients were diagnosed with ATTR-CM in a tertiary referral center. Of those, 63 were prospectively evaluated for the presence of ventricular arrhythmias using 24 hours Holter-ECG. Ventricular arrhythmias were further characterized as sustained (sVT) and non-sustained ventricular tachycardias (nsVT). Results In our cohort of unselected ATTR-CMP patients the prevalence of ventricular tachycardias was high with 47.6 % (n= 30/63). Of those, the majority were non-sustained VTs (84%) and the minority sustained VT (16%). Patients with ventricular tachycardias showed significantly more severe left ventricular (LV) hypertrophy, reduced LV ejection fraction (LV-EF) and larger left atrial volumes as well as a trend towards smaller LV cavities (table 1). Interestingly, no significant differences in prevalence of coronary artery disease or cardiac markers such as NTproBNP and troponin were seen between patients with and without ventricular tachycardias (table 1). Furthermore, we evaluated the multivariable predictive performance for discriminating between patients with and without ventricular tachycardias using two backward variable selection procedures (model 1 p-value based and model 2 Akaike information criterion (AIC) based). In the first model, LVEF (OR = 0.865 [0.776;0.963], p=0.008), LVEED (0.837 [0.708;0.991], p=0.039), and LV mass indexed by BSA (1.028[1.003;1.055], p=0.031) remained independent predictors of occurrence of ventricular arrhythmias, while in the second model sodium concentration (1.287 [0.929;1.783], p=0.129) and betablocker medication (5.078, [0.819;31.477], p=0.081) also were retained. Comparing the area under the Receiver Operating-Characteristic (AUROC) we observed no significant difference between both models (AUROC: 0.846 [0.711;0.937] vs. 0.870 [0.737;0.951], p=0.57, figure 1). Conclusion The prevalence of ventricular tachycardia in ATTR-CM is high. Patients with ventricular tachycardia show advanced stage of left ventricular disease, with LVEDD, LV-EF and LV mass indexed by BSA being predictors of ventricular tachycardias in two multivariable predictive models. Further studies validating the predictive value of those variables are needed, including the assessment of nsVT and sVT in predicting sudden cardiac death, possibly allowing the use as a risk score for ventricular arrhythmias.

Left Atrial Function in Patients with Titin Cardiomyopathy

BackgroundTruncating variants in titin (TTNtv) are the most prevalent genetic etiology of dilated cardiomyopathy (DCM). Although TTNtv has been associated with atrial fibrillation, it remains unknown whether and how left atrial (LA) function differs between patients with DCM with and without TTNtv. We aimed to determine and compare LA function in patients with DCM with and without TTNtv and to evaluate whether and how left ventricular (LV) function affects the LA using computational modeling. Methods and ResultsPatients with DCM from the Maastricht DCM registry that underwent genetic testing and cardiovascular magnetic resonance (CMR) were included in the current study. Subsequent computational modeling (CircAdapt model) was performed to identify potential LV and LA myocardial hemodynamic substrates. In total, 377 patients with DCM (n = 42 with TTNtv, n = 335 without a genetic variant) were included (median age 55 years, interquartile range [IQR] 46–62 years, 62% men). Patients with TTNtv had a larger LA volume and decreased LA strain compared with patients without a genetic variant (LA volume index 60 mLm−2 [IQR 49–83] vs 51 mLm−2 [IQR 42–64]; LA reservoir strain 24% [IQR 10–29] vs 28% [IQR 20–34]; LA booster strain 9% [IQR 4–14] vs 14% [IQR 10–17], respectively; all P < .01). Computational modeling suggests that while the observed LV dysfunction partially explains the observed LA dysfunction in the patients with TTNtv, both intrinsic LV and LA dysfunction are present in patients with and without a TTNtv. ConclusionsPatients with DCM with TTNtv have more severe LA dysfunction compared with patients without a genetic variant. Insights from computational modeling suggest that both intrinsic LV and LA dysfunction are present in patients with DCM with and without TTNtv.

Impact of sex on severity assessment and cardiac remodeling in primary mitral regurgitation due to valve prolapse

The current recommended cut-off values for primary mitral regurgitation (MR) quantification (Effective Regurgitant Orifice Area [EROA], regurgitant volume [RegVol]) and left ventricular (LV) remodeling in MR (end-systolic diameter [ESD]) are not sex-specific. We retrospectively evaluated 470 patients (27% women, median age 63 years) with chronic significant primary MR due to prolapse who underwent echocardiography (Echo) and cardiac magnetic resonance imaging (CMR) in 3 tertiary centers between 2005 and 2022. Women were older than men, had higher NYHA class, larger left atrial volume, higher pulmonary pressure, and more symptoms-triggered MV intervention (all P < 0.035). However, both MR EROA, Echo-RegVol and CMR-RegVol were lower in women than in men (all P < 0.003), while CMR regurgitant fraction (RegFrac) values were similar (P = 0.890). Abnormally increased CMR- (> upper limit bound of UK Biobank reference values) indexed LV end-diastolic (indLVEDV), end-systolic volume (indLVESV) were observed in 55%, 29% of patients, respectively, without sex difference (P = 1, P = 0.9). The optimal cut-off values of MR EROA, Echo-RegVol and CMR-RegVol associated with enlarged indLVEDV were lower in women (40 mm2, 60 mL, 50 mL) than in men (45 mm2,77 mL, 62 mL). LVESD ≥ 40 mm showed in women and men high specificity [Sp] (91%, 79%) but poor sensitivity [Se] (40% 50%) to predict enlarged indLVESV, while the optimal threshold was slightly lower in women (35 mm, Se = 65%, Sp = 71%) than in men (37 mm, Se = 65%, Sp = 68%). Despite clear hallmarks of more advanced valve disease, women with primary MR have lower mitral RegVol and lower ventricular volumes than men. Then, cut-off values of mitral RegVol, EROA and LV dimensions for predicting abnormal LV dilatation are lower in women than in men. Hence, guideline-based criteria for grading MR and timing of intervention could be sex-specific (Fig. 1).

Long-term outcome of thoracoscopic ablation and radiofrequency catheter ablation for persistent atrial fibrillation as a de novo procedure

Limited data are available regarding the efficacy of thoracoscopic ablation as the first procedure for persistent atrial fibrillation (AF). We sought to compare the long-term efficacy of thoracoscopic ablation vs. radiofrequency (RF) catheter ablation as the first procedure for persistent AF. Between February 2011 and December 2020, 575 patients who underwent ablation for persistent AF were studied. Among them, thoracoscopic ablation was performed in 281 patients, RF catheter ablation in 228, and hybrid ablation in 66. Rhythm, clinical, and safety outcomes during 7-year follow-up were compared. The patients who underwent thoracoscopic ablation were older, had a higher prevalence of stroke, and had a larger left atrial volume than those who underwent RF catheter ablation. In the propensity score-matched population (n = 306), incidences of atrial tachyarrhythmia recurrence were 51.4% in the thoracoscopic ablation group and 62.5% in the RF catheter ablation group [adjusted hazard ratio (HR) 0.869, 95% confidence interval (CI) 0.618-1.223, P = 0.420]. Stroke and total procedural adverse events were not significantly different between thoracoscopic and RF catheter ablation (2.7 vs. 2.5%, P = 0.603, and 7.1 vs. 4.8%, P = 0.374, respectively). The hybrid ablation group showed similar rhythm outcomes compared with both the thoracoscopic and the RF catheter ablation groups. At the redo procedure, pulmonary vein gaps were more frequently observed in the RF catheter ablation group (32.6%) than in the thoracoscopic ablation group (7.9%) and in the hybrid ablation group (8.8%) (P < 0.001). As a first procedure in persistent AF, thoracoscopic ablation and RF catheter ablation showed comparable efficacy, clinical, and safety outcomes during long-term follow-up.

CE-452780-1 LEFT ATRIAL VOLUME IS THE STRONGEST PREDICTOR OF ATRIAL ARRHYTHMIA RECURRENCE AFTER PULMONARY VEIN ISOLATION ALONE IN PERSISTENT AF: A DECAAF II SUBSTUDY

Left atrial volume (LAV) is a known predictor of atrial arrhythmia recurrence (AAR) after pulmonary vein isolation (PVI). We sought to assess the role of LAV in predicting AAR in pts with persistent atrial fibrillation (PrAF) undergoing PVI alone as the initial procedure. The DECAAF II Trial was a prospective randomized trial of pts with PrAF undergoing initial ablation. Baseline demographics and risk factors were collected for all pts, who also underwent late gadolinium enhanced magnetic resonance imaging for calculation of baseline LAV and atrial fibrosis. Of 408 pts in the control group (PVI alone), 47 were excluded predominantly due to receiving additional LA ablation. The remaining 361 pts constituted the study population. Pts provided single-lead home ECG strips once daily and during symptoms. The primary endpoint was single-procedure success, defined as freedom from AAR (AF, flutter or atrial tachycardia > 30 sec) following a 90-day blanking period through 365 days post-procedure. A receiver operating curve (ROC) was performed to identify the optimal LAV predicting success. A covariate adjusted Cox regression model was performed to identify independent predictors of outcome. At baseline, the mean pt age was 62±9 yrs, and 80% were male. Mean fibrosis was 19±8%, and median LAV was 129 cc (IQR: 104-154). ROC analysis identified LAV < 114 cc as the optimal cut-point. In the Cox model, LAV < 114 cc was the only significant predictor of procedural success (p=0.004) with a hazard ratio of 0.53 (95% CI 0.35-0.82,table). Pts with LAV < 114 cc had one year freedom from RAA of 73% (95% CI 65-81%) vs 53% (95% CI 47-60%) in pts with larger LAV (p=0.00043,log-rank,figure). Baseline LAV < 114 cc was present in 120/361 pts (33%). LAV is the strongest predictor of RAA in pts with PrAF undergoing PVI alone as the first ablation procedure. PVI may be a reasonable initial approach for PrAF ablation in pts with small LAV.Tabled 1Left Atrial (LA) volume as a predictor of AF recurrence using Cox regression analysis. CHF: Congestive Heart Failure. HTN: Hypertension. BMI: Body Mass Index.Variable (Ref)Estimatep-valueHazard ratio [95% CI]Age (Years)0.012±0.00110.2581.01 [0.99 - 1.03]Sex (Male)-0.291±0.2240.1950.75 [0.48 - 1.16]Baseline Fibrosis-0.006±0.0130.6590.99 [0.97 - 1.02]Antiarrhythmics history (Yes)-0.068±0.1980.7300.93 [0.63 - 1.38]CHF (Yes)0.151±0.2400.5291.16 [0.73 - 1.86]HTN (Yes)0.103±0.1930.5941.11 [0.76 - 1.62]History of Stroke (Yes)0.188±0.3110.5461.21 [0.66 - 2.22]Tobacco (Yes)0.264±0.1830.1491.30 [0.91 - 1.87]Failed antiarrhythmics treatment (Yes)0.107±0.1990.5931.11 [0.75 - 1.64]BMI0.026±0.0160.0941.03 [1.00 - 1.06]LA Volume (<114)-0.631±0.2190.0040.53 [0.35 - 0.82] Open table in a new tab

A novel echocardiographic risk score for light-chain amyloidosis.

The prognosis of light-chain (AL) amyloidosis, a plasma cell dyscrasia, is largely determined by the presence of cardiac involvement. Conventional staging is achieved using cardiac biomarkers (high-sensitivity troponin, N-terminal pro-beta natriuretic peptide) and free light-chain difference (Mayo staging). We sought to evaluate the role of echocardiographic parameters as prognostic markers in AL amyloidosis and examine their utility compared with conventional staging. Seventy-five consecutive patients with AL amyloidosis reviewed at a referral amyloid clinic who underwent comprehensive echocardiographic assessment were retrospectively identified. The evaluated echocardiographic parameters included left ventricular (LV) ejection fraction, mass, diastolic function parameters, global longitudinal strain (GLS), and left atrial (LA) volume. Mortality was assessed through a review of clinical records. During a median follow-up of 51 months, 29/75 (39%) patients died. Patients who died had a larger LA volume (47 ± 12 vs. 35 ± 10 mL/m2, P < 0.001) and a higher E/e' (18 ± 10 vs. 14 ± 6, P = 0.026). Univariate clinical and echocardiographic predictors of survival included LA volume, E/e', e', LVGLS, and Mayo stage (at significance of P < 0.1). Left atrial volume and LVGLS were significant determinants of mortality when examined using clinical cut-offs, although E/e' was not. A composite echocardiographic risk score comprising LA volume and LVGLS provided similar prognostic performance to Mayo stage [area under the curve (AUC) 0.75, 95% confidence interval (CI) 0.64-0.85 vs. AUC 0.75, 95% CI 0.65-0.858, P = 0.91]. Left atrial volume and LVGLS were independent predictors of mortality in AL amyloidosis. A composite echocardiographic score combining LA volume and LVGLS has similar prognostic power to Mayo stage for all-cause mortality.

Gender-related differences in left atrial strain mechanics and exercise capacity in hypertrophic cardiomyopathy: a propensity-score matched study from the Cleveland Clinic.

Male and female patients with hypertrophic cardiomyopathy (HCM) differ in physiologic characteristics and hemodynamics. Little is known about gender-related differences in left atrial (LA) strain and exercise capacity. The aim of this study was to assess the gender-related differences in the relationship between exercise capacity and cardiac function including LA function in patients with HCM. Five hundred and thirty-two patients with HCM undergoing exercise stress echocardiography and cardiopulmonary exercise testing (CPET) were prospectively recruited between October 2015 and April 2019 as part of a cohort study in a quaternary referral center. To reduce potential confounding factors, propensity score (PS) matching was performed in 420 patients. LA strain mechanics were evaluated using speckle-tracking echocardiography. The majority of patients were male, comprising 58% of the total. Female HCM patients were older (54±14 vs. 50±15 years, P=0.002). After PS matching, percent-predicted peak VO2 was similar between the genders (67.5%±20.7% vs. 65.8%±21.8%, P=0.41), even though female HCM patients had lower peak VO2 (17.7±5.9 vs. 24.1±8.3 mL/kg/min, P<0.001). Left ventricular (LV) diastolic function was worse for female HCM patients. This is shown by worse E/e' ratio (15.0±5.9 vs. 12.9±6.4, P<0.001) and larger LA volume in respect to LV (0.88±0.35 vs. 0.74±0.31, P<0.001), compared with male HCM patients. The gender-related differences in LA reservoir strain were more evident for patients aged 60 years and older (27.5%±8.8% vs. 30.9%±9.1%, P=0.03). LA reservoir strain was found to have a significant association with exercise capacity in both male and female HCM patients (for females, β=0.27, P=0.001; for males, β=0.27, P<0.001), independent of LV diastolic dysfunction and stroke volume. Gender-related differences in LA reservoir strain were increasingly evident for older HCM patients aged 60 years and older. LA reservoir strain was an independent determinant of percent-predicted peak VO2 in male and female patients, underpinning the importance of LA function in determining exercise capacity in HCM.

Echocardiographic Characteristics and Clinical Outcomes of the Hyperdynamic Heart: A ‘Super-Normal’ Heart is not a Normal Heart

A hyperdynamic heart is defined as a left ventricular (LV) with an ejection fraction (EF) above the normal range. Is this favorable? We looked at the diastolic properties of subjects with a hyperdynamic heart and its impact on outcome. Consecutive echocardiography examinations during 5years were evaluated by EF subgroups, including a hyperdynamic heart (EF >70%). All examinations with significant LV hypertrophy or valve disease were excluded. The study included 16,994 subjects. A total of 720 subjects (4.2%) had a hyperdynamic heart. Subjects with a hyperdynamic heart were older, more likely to be women, and more likely to have hypertension, diabetes, and obesity. A total of 20% of patients had a diagnosis of heart failure. This group had a higher heart rate, smaller ventricular size, and the highest relative wall thickness. All indexes of diastolic dysfunction were significantly more prevalent in the hyperdynamic group. This included a higher LV mass, larger left atrial volume, reduced relaxation (smaller mitral e'), longer deceleration time, and higher LV end-diastolic pressures (high mitral E/e' ratio) and peak tricuspid regurgitation gradient. Diastolic dysfunction, defined by an abnormal functional or structural parameter, was present in 78% of the subjects. Survival was significantly lower in the group with a hyperdynamic heart. The Cox regression analysis after adjustment demonstrated reduced survival during a median 9-year follow-up in the hyperdynamic group compared with those with a normal EF (hazard ratio 1.56, 95% confidence interval 1.38 to 1.76, p <0.001). In conclusion, subjects with a hyperdynamic systolic function have increased prevalence of diastolic dysfunction and reduced survival. A hyperdynamic heart is not a normally functioning heart.

Abstract 12425: The Interplay Between Left Atrial and Mitral Valvular Remodeling in Subtypes of Mitral Regurgitation

Background: The interaction between left atrial (LA) mechanics and mitral valve remodeling patterns in patients with mitral regurgitation (MR) is poorly described. Objectives: To assess three-dimensional (3D) LA volumes and strain in relation to 3D mitral valve morphology in patients with degenerative vs. functional MR. Methods: Patients included in the 3D-PRIME (3D Echocardiography and Cardiovascular Prognosis in Mitral Regurgitation) study at our heart valve clinic between 2020-2022 and with moderate or severe MR by combined transthoracic/transesophageal assessment were examined. LA remodeling was assessed by 3D maximum and minimum LA volume, reservoir strain (LASr) and contraction strain (LASct). Mitral valve annulus area, anterior and posterior leaflet length and area, tenting volumes and non-planar angle were measured using dedicated 3D mitral valve software. Results: 100 patients with moderate or severe MR were included. Patients with atrial functional MR (n=26) were older, more often women and had higher heart rate compared to degenerative MR (n=54) and ventricular functional MR (n=20) (p &lt;0.05). They also had larger LA volumes and severely impaired LASr and LASct despite smaller MR regurgitation volumes compared to MR by other mechanisms (Figure). Mitral annulus area was comparable between groups, but anterior mitral leaflet was higher, with larger area and the non-planar angle wider in functional MRs (p &lt;0.05). In multivariable analysis, low LASr (below median) was associated with larger LA volume, and higher anterior mitral leaflet height independent of age, sex, heart rate, left ventricular global longitudinal strain, and right ventricular stroke volume (Nagelkerke R 2 0.67, p &lt;0.01). In a similar model, low LASct was only associated with larger LA volumes. Conclusions: Patients with atrial functional MR have large LAs with severely impaired LA function and a specific mitral valve remodeling pattern at lower MR regurgitation volumes.

The association between native myocardial T1 relaxation times and left atrial phasic structure and function: the UK Biobank Imaging Enhancement study

Abstract Introduction Left ventricular (LV) myocardial fibrosis is posited to result in left atrial (LA) changes via LV remodelling and diastolic dysfunction, though the association remains poorly characterised. Native myocardial T1 mapping is a non-invasive modality that quantifies diffuse myocardial fibrosis. This study examines the relationship between LV fibrosis (quantified by native T1 times) and LA function, drawing upon data from the UK Biobank. Methods 40,818 participants underwent cardiovascular magnetic resonance (CMR) using steady-state free precession imaging at 1.5 Tesla. Native T1-mapping was performed using the Shortened Modified Look-Locker Inversion recovery technique (ShMOLLI), with global myocardial T1 estimated by an automatic segmentation framework. Nine parameters of LA phasic function were calculated (representing global, reservoir, conduit and booster components) from normalised LA volume-time curves. LV parameters (LV Mass, end-diastolic volume and ejection fraction) were extracted by a convolutional neural network. Multivariable logistic regression models were used to assess the association between T1 (exposure) and LA function (outcome). Mediation analysis was performed to assess the role of LV parameters as a mediator for the association between T1 and LA function. Lastly, potential non-linear relationships between T1 and LA function were investigated using Restrictive Cubic Spline (RCS) modelling, with model fit assessed via the Akaike Information Criterion (AIC). Results Higher T1 values were positively associated with larger LA volumes, and negatively associated with markers of LA global, reservoir and booster function. In the fully adjusted model, T1 was positively associated with larger LA minimum size (Beta: +0.034 SD per T1 SD; Confidence Interval (CI): 0.024, 0.045), and negatively associated with LA emptying volume (Beta: −0.017; CI: −0.027, −0.006), LA booster volume (Beta: −0.019; CI: −0.030, −0.008), LA emptying fraction (Beta: −0.052; CI: −0.062, −0.041), and LA reservoir function (Beta: −0.028; CI: −0.039, −0.017). Though adjustment for LV parameters did not fully attenuate the above relationships, LV parameters were consistent mediators between T1 and LA function, with proportional mediative effects ranging from 15% to 75%. Lastly, there is evidence of an inverted J-shaped relationship between T1 and LA function, with the associations becoming more apparent in the upper half of T1 ranges (turning points within 925–950 ms, median T1 = 930 ms) (p&amp;lt;0.05). Conclusion This study demonstrates a consistent association between higher native T1 values (as a marker of myocardial fibrosis) and lower LA global and phasic functions. We also highlighted an interplay between T1 values, LV remodelling and LA dysfunction. These findings will facilitate our understanding of the disease processes underlying cardiac dysfunction and myocardial remodelling at an early, subclinical stage. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): This work was part of the portfolio of translational research of the National Institute for Health Research Biomedical Research Centre at Barts and The London School of Medicine and DentistryDr Nay Aung is supported by a Wellcome Trust Research Training Fellowship (203553/Z/16/Z)

Effectiveness of transcatheter edge-to-edge repair for atrial secondary mitral regurgitation

Abstract Background Atrial secondary mitral regurgitation (ASMR) is a subtype of SMR that is characterized by normal left ventricular (LV) function, an enlarged left atrium and mitral annulus, and flattened leaflets. This anatomical feature is different from ventricular SMR (VSMR) and might therefore impact the procedural results of transcatheter edge-to-edge repair (TEER). The effectiveness and durability of TEER in patients with ASMR has not yet been well-studied. Purpose This study aimed to investigate the effectiveness of TEER and anatomical characteristics related to optimal MR reduction in patients with ASMR. Methods We retrospectively analyzed consecutive patients who underwent MitraClip at our institution. ASMR was defined as cases that met all of the following criteria: 1) normal mitral leaflets without organic disorder, 2) LV ejection fraction &amp;gt;50%, and 3) absence of LV enlargement and segmental abnormality. The primary outcome measure was MR reduction to ≤1+, and its predictors were explored in a logistic regression analysis. Leaflet-to-annulus index (LAI) was measured using the mid-esophageal long-axis view in the A2-P2 segment as follows: (anterior leaflet length + posterior leaflet length) / anteroposterior length of the mitral annulus. Results Among 415 patients with SMR, 118 patients met the criteria for ASMR (mean age: 80±8 years; male: 39.8%) (Figure 1). Patients with ASMR had a larger mitral annulus diameter, shorter mobile posterior leaflet length, and smaller coaptation depth compared to those with VSMR. The technical success rate was 90.7%, and the MR reduction to ≤1+ after TEER was achieved in 94 (79.7%) patients with ASMR, which was comparable with VSMR. The in-hospital mortality rate was 2.5%. In multivariable logistic analysis, a large left-atrial (LA) volume index and a low LAI were associated with a lower rate of MR reduction to ≤1+ after TEER for ASMR (odds ratio [OR]: 0.98; 95% confidence interval [CI]: 0.97–0.99, and OR per 0.1 increase: 1.98; 95% CI: 1.13–3.45, respectively). The combined assessment of the LA volume index and LAI stratified the risk of residual MR ≥2+ after TEER (Figure 2). In addition, the use of a newer generation of the MitraClip systems (NTR/XTR or G4 systems) was associated with a higher rate of MR reduction to ≤1+ compared to older generations (OR: 4.65; 95% CI: 1.67–13.00). Conclusions TEER with the MitraClip system achieved a high rate of MR reduction to ≤1+ in patients with ASMR. Furthermore, the new generations of the MitraClip system may provide a more effective reduction in ASMR. Although our findings suggest that TEER with the MitraClip system is a safe and feasible approach in patients with ASMR, the combined assessment of the LA volume index and LAI might be useful to refine the device selection for transcatheter mitral valve treatment in this subgroup of SMR patients. Funding Acknowledgement Type of funding sources: None.

Effect of Bi-Atrial Size and Function in Patients With Paroxysmal or Permanent Atrial Fibrillation

Atrial fibrillation (AF) remains the most common arrhythmia in clinical practice. The choice between a rate-control and rhythm-control strategy depends on various factors, including the anatomical and functional substrate. This study investigates the anatomical and functional characteristics of both atria in patients with AF and explores the potential therapeutic implications. From an ongoing registry of patients with paroxysmal or permanent AF, those who underwent cardiac computed tomography (CCT) were included. Left atrial (LA) and right atrial (RA) sizes were measured on CCT, whereas bi-atrial function was quantified with speckle tracking strain echocardiography. The mean LA volume index was 41.6 ± 5.6 ml/m2, and the mean RA volume index was 71.0 ± 21.6 ml/m2. Mean LA reservoir strain was 24.3 ± 15.1%, compared with the mean RA reservoir strain of 21.6 ± 13.2%. Patients with smaller LA volumes had higher LA reservoir strain values than those with larger LA volumes (24.6% [interquartile range (IQR) 15.8 to 35.8] vs 16.5% [IQR 11.2 to 25.0], p <0.001). Patients with permanent AF had larger LA volumes (44.0 [IQR 33.7 to 55.2] ml/m2 vs 36.9 [IQR 30.1 to 47.1] ml/m2, p=0.025) compared with paroxysmal AF. Patients with permanent AF had more impaired LA reservoir strain (15.5% [IQR 11.6 to 22.7] vs 26.9% [IQR 17.4 to 35.6], p <0.001) compared with paroxysmal AF. Similar trends were observed in the RA. In conclusion, atrial substrate characterization by CCT and speckle tracking strain echocardiography may have therapeutic implications, especially for choosing between a rate-control and rhythm-control strategy.

Transcatheter Edge-to-Edge Repair for Atrial Secondary Mitral Regurgitation

BackgroundAtrial secondary mitral regurgitation (ASMR) is a subtype of SMR that has a poor prognosis, and thus far, evidence of the therapeutic options for the management of ASMR is limited. ObjectivesThis study aimed to investigate the effectiveness of transcatheter edge-to-edge repair (TEER) for ASMR. MethodsThe study retrospectively analyzed consecutive patients who underwent MitraClip at the Heart Center Bonn. ASMR was defined as cases that met all of the following criteria: 1) normal mitral leaflets without organic disorder; 2) left ventricular ejection fraction >50%; and 3) absence of LV enlargement and segmental abnormality. The primary outcome measure was MR reduction to ≤1+, and its predictors were explored in a logistic regression analysis. ResultsAmong 415 patients with SMR, 118 patients met the criteria for ASMR (mean age 80 ± 8 years, 39.8% male). The technical success rate was 94.1%, and MR reduction to ≤1+ after TEER was achieved in 94 (79.7%) patients with ASMR. The in-hospital mortality rate was 2.5%. In multivariable logistic analysis, a large left atrial volume index and low leaflet-to-annulus index were associated with a lower incidence of MR reduction to ≤1+ after TEER for ASMR. In addition, the use of a newer generation of the MitraClip systems (NTR/XTR or G4 systems) was associated with a higher incidence of MR reduction to ≤1+. ConclusionsTEER is a safe and feasible therapeutic option for patients with ASMR. Assessments of left atrial volume index and leaflet-to-annulus index may assist with patient selection for TEER in patients with ASMR.

Relation of a Filling Defect of Left Atrial Appendage by Contrast Computed Tomography Image With Subsequent Clinical Events in Patients With Atrial Fibrillation Receiving Catheter Ablation Procedures

Filling defect (FD) in left atrial appendage (LAA) is commonly observed in contrast computed tomography (CT) among patients with atrial fibrillation (AF), although its prognostic impact has not been well explored. We enrolled 1,019 consecutive patients who underwent AF ablation with baseline contrast CT images. FD in LAA was graded into 3 groups: grade 0 for complete filling (79.7%), grade 1 for incomplete filling (12.6%), and grade 2 for complete FD (7.8%). We evaluated the impact of the FD grade on the long-term clinical outcomes during the mean follow-up of 4.4 ± 2.0 years. Patients with grade 2 FD had higher prevalence of nonparoxysmal AF, higher brain natriuretic peptide level, and larger left atrial volume than those with grade 0 or 1 FD. The 5-year cumulative incidence of recurrent atrial tachyarrhythmias was higher in patients with grade 2 FD than those with grade 0 or 1 FD (74.0% vs 38.8% and 62.1%, log-rank p &lt;0.001). The 5-year cumulative incidence of major adverse cardiovascular events (MACEs), defined as a composite of all-cause death, heart failure hospitalization, and ischemic stroke, was also significantly higher in patients with grade 2 FD (19.4% vs 5.6% and 9.5%, log-rank p &lt;0.001). Follow-up CT images acquired in 87.1% of patients at median interval of 98 days showed significantly decreased FD (grade 1 in 4.5% and grade 2 in 2.1%, p &lt;0.001). The residual grade 2 FD at follow-up was associated with significantly higher risk for subsequent MACEs. In conclusion, among patients with AF receiving catheter ablation, severe FD in LAA in contrast CT was associated with higher incidence of arrhythmia recurrence and MACEs during follow-up.

Serum periostin as a predictor of early recurrence of atrial fibrillation after catheter ablation

Catheter ablation is an effective method of rhythm therapy for atrial fibrillation (AF). AF recurrence is a common problem after catheter ablation. The aim of this study was to investigate influence factors of early recurrence after catheter ablation for AF. One hundred and three consecutive patients with AF were enrolled and underwent catheter ablation. Venous blood (Marked as A) was collected before ablation and left atrial blood (Marked as B) was collected after successful atrial septal puncture to detect serum periostin. After 3months of follow-up, statistical analysis was made based on the recurrence of AF. 27 (26.2%) patients had a recurrence of atrial arrhythmia after catheter ablation. Patients with recurrent atrial arrhythmia had a larger left atrial volume (162.31 ± 47.76 vs. 141.98 ± 41.64,p = 0.039), and higher serum periostin levels (periostin A. 99.71 ± 16.475 vs. 90.36 ± 13.63, p = 0.005; periostin B. 103.95 ± 13.09 vs. 94.46 ± 15.85, p = 0.006) compared with the non-recurrent group. The numbers of patients with left atrial low-voltage areas (LVAs) were more in the recurrence group (p < 0.001). Left atrial volume, serum periostin and left atrial LVAs were included in univariate and multivariate COX regression analysis. It showed that left atrial LVAs (HR3.81; 95% CI 1.54 to 9.44; p = 0.004) and serum periostin A (HR1.07; 95% CI 1.02 to1.13; p = 0.008) were the independent predictors of AF recurrence. The cut-off value of serum periostin A was 87.95ng/ ml (AUC, 0.681; sensitivity 88.9% and specificity 53.9%). Kaplan-Meier survival curve showed that the recurrence rate of AF was higher in patients with left atrial LVAs and higher serum periostin. The venous serum periostin level and left atrial LVAs were independent predictors of early recurrence of AF after catheter ablation.

Exercise-induced pulmonary hypertension in hypertrophic cardiomyopathy: a combined cardiopulmonary exercise test-echocardiographic study.

Pulmonary arterial hypertension (PAH), documented in a significant portion of hypertrophic cardiomyopathy (HCM) patients, has been shown to adversely impact prognosis. In most HCM patients congestive symptoms are consistently elicited by exercise, thus suggesting the need for a provocative test to assess cardiac hemodynamics during effort. Combining cardiopulmonary exercise test (CPET) with echocardiography, we aimed to evaluate the presence of exercise induced pulmonary arterial hypertension (EiPAH), its role in functional limitation and its prognostic significance in a cohort of patients with obstructive and non-obstructive HCM. Study population included 182 HCM patients evaluated combining CPET and stress echocardiography. Left-ventricular outflow tract (LVOT) velocities, trans-tricuspid gradient, and cardiopulmonary variables were continuously measured. Thirty-seven patients (20%) developed EiPAH, defined as systolic pulmonary arterial pressure (sPAP) > 40mmHg during exercise. EiPAH was associated with lower exercise performance, larger left atrial volumes, higher LVOT gradient and higher VE/VCO2 slope. At multivariable analysis baseline sPAP (p < 0.0001) and baseline LVOT obstruction (p = 0.028) were significantly associated with EiPAH. Kaplan-Meier curve analysis showed EiPAH was a significant predictor of HCM-related morbidity (Hazard Ratio 6.21, 95% CI 1.47-26.19; p = 0.05; 4.21, 95% CI 1.94-9.12; p < 0.001 for the primary and the secondary endpoint respectively). EiPAH was present in about one fifth of HCM patients without evidence of elevated pulmonary pressures at rest and was associated with adverse clinical outcome. Diagnosing EiPAH by exercise echocardiography/CPET may help physicians to detect early stage of PAH thus allowing a closer clinical monitoring and individualized therapies.

Effect of single ventricular premature contractions on response to cardiac resynchronization therapy

BackgroundWe lack data on the effect of single premature ventricular contractions (PVCs) on the clinical and echocardiographic response after cardiac resynchronization therapy (CRT) device implantation. We aimed to assess the predictive value of PVCs at early, 1 month-follow up on echocardiographic response and all-cause mortality.MethodsIn our prospective, single-center study, 125 heart failure patients underwent CRT implantation based on the current guidelines. Echocardiographic reverse remodeling was defined as a ≥ 15% improvement in left ventricular ejection fraction (LVEF), end-systolic volume (LVESV), or left atrial volume (LAV) measured 6 months after CRT implantation. All-cause mortality was investigated by Wilcoxon analysis.ResultsThe median number of PVCs was 11,401 in those 67 patients who attended the 1-month follow-up. Regarding echocardiographic endpoints, patients with less PVCs develop significantly larger LAV reverse remodeling compared to those with high number of PVCs. During the mean follow-up time of 2.1 years, 26 (21%) patients died. Patients with a higher number of PVCs than our median cut-off value showed a higher risk of early all-cause mortality (HR 0.97; 95% CI 0.38–2.48; P = 0.04). However, when patients were followed up to 9 years, its significance diminished (HR 0.78; 95% CI 0.42–1.46; P = 0.15).ConclusionsIn patients undergoing CRT implantation, lower number of PVCs predicted atrial remodeling and showed a trend for a better mortality outcome. Our results suggest the importance of the early assessment of PVCs in cardiac resynchronization therapy and warrant further investigations.