Atrioventricular Coupling Research Articles

Accelerated atrial pacing reduces left-heart filling pressure: a combined clinical-computational study.

Accelerated atrial pacing offers potential benefits for patients with heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF), compared with standard lower-rate pacing. The study investigates the relationship between atrial pacing rate and left-heart filling pressure. Seventy-five consecutive patients undergoing catheter ablation for AF underwent assessment of mean left atrial pressure (mLAP) and atrioventricular (AV) conduction delay (PR interval) in sinus rhythm and accelerated atrial pacing with 10 bpm increments up to Wenckebach block. Computer simulations (CircAdapt) of a virtual HFpEF cohort complemented clinical observations and hypothesized the modulating effects of AV coupling and atrial (dys)function. In the study cohort, 49(65%) patients had a high HFpEF likelihood (H2FPEF ≥ 5.0), and 28(37%) an elevated mLAP ≥ 15 mmHg at sinus rhythm. Optimal pacing rates of 100 [70-110]bpm (median [IQR]) significantly reduced mLAP from 12.8 [10.0-17.4]mmHg in sinus rhythm (55 [52-61]bpm) to 10.4 [7.8-14.8]mmHg (P < .001). Conversely, higher pacing rates (130 [110-140]bpm) significantly increased mLAP to 14.7 [11.0-17.8]mmHg (P < .05). PR interval and, hence, AV conduction delay prolonged incrementally with increasing pacing rates. Simulations corroborated these clinical findings, showing mLAP reduction at a moderately increased pacing rate and a subsequent increase at higher rates. Moreover, simulations suggested that mLAP reduction is optimized when AV conduction delay shortens with increasing rate. Accelerated pacing acutely reduces left-heart filling pressure in patients undergoing AF catheter ablation and computer simulations with HFpEF features, suggesting it as a potential therapeutic strategy to alleviate congestion symptoms. Virtual HFpEF patient cohorts hypothesize that AV sequential pacing may further optimize this therapy's beneficial effects.

Abstract 4121348: Impairments in Left Atrioventricular Coupling Underpins Reductions in Skeletal Muscle Mass and Function in Ageing Older Adults

Background: Age-related cardiovascular disease (CVD) may manifest with changes in left ventricular (LV) systolic or left atrial (LA) dysfunction. Alterations in functional performance between the LV and LA chambers characterized by LA-LV coupling may be a sensitive marker representative of impairments in global cardiac performance, compared to either chamber alone. The increasing relevance of skeletal muscle function towards cardiac health in ageing, motivated our current work that investigated associations between skeletal muscle function and LA-LV coupling. Aim : Using advanced cardiac magnetic resonance (CMR) that characterizes cardiac volumetric parameters and strain functions, we determined the association between handgrip strength (HGS) and appendicular lean mass (ALM) with left atrioventricular coupling index (LACI). Methods: Community older adults without CVD underwent simultaneous assessment of HGS by hand dynamometer, height-square adjusted ALM by bio-impedance, and LA phasic function (namely reservoir, conduit, booster strain) as well as LA and LV volumetric parameters by CMR feature tracking. LACI is defined as the ratio of the ratio of LA to LV end-diastolic volumes. We performed linear regression and multivariable logistic regression to examine the relationship between HGS/ALM and LACI. Results: Among 251 study participants (mean age: 71 ± 9.1 years, female 44.7%), 149 (59%) had impaired LACI. HGS was linearly associated with LACI (β=-0.004, p=0.003) and LVEDV (β=1.62, p&lt;0.0001), and ALM was linearly associated with LA volume (β=0.55, p=0.018) and LVEDV (β=3.45, p&lt;0.0001) (Figure.1). Participants with impaired LACI (&gt; 25%) had lower HGS (mean=22.8 ± 7.1 kg vs 26.1 ± 6.4 kg, p= 0.0002), lower ALM (16.4 ± 4.2 kg/m2 vs 17.7 ± 3.8 kg/m2, p=0.014), higher LA volume (36.8 ± 15.2 ml vs 22.0 ± 5.5 ml, p &lt; 0.0001) and lower LV end-diastolic volume (101.0 ± 24.2 ml vs 111.9 ± 27.3 ml, p = 0.0011). The association between impaired LA-LV coupling and lower HGS (β=-0.0647, 95%CI -0.0255, -0.1040, p=0.001) and lower ALM (β=-0.0776, 95%CI -0.0107, -0.1444, p=0.011) persisted after adjusting for age. Conclusion: Reduced HGS and ALM among community-dwelling older adults was associated with impaired LA-LV coupling suggestive of underlying early-stage LA remodelling and impairments in left atrioventricular compliance. Detection of reduced HGS and ALM in community cohorts may prompt early identification of older adults at risk of dysfunctional cardiac aging.

Effects of cardiac resynchronization therapy and physiologicaL pacing on left atrioventricular coupling index: the REPHYL-LACI study

Abstract Introduction Cardiac dyssynchrony and right ventricular pacing are associated with left atrial (LA) remodeling and atrioventricular uncoupling. Cardiac resynchronization therapy -CRT and conduction system pacing –CSP are important therapeutic options. Left atrioventricular coupling index (LACI) is a novel imaging parameter useful to describe the relationship between LA and left ventricle (LV). It could be measured as the ratio between LA end-diastolic volume (EDV) and the LV EDV or, alternatively, as the LA volume indexed for body surface area (LAVi) divided for a’ measured by tissue Doppler imaging (TDI) at medial mitral annulus level. Higher values indicate greater impairment of atrioventricular coupling. However, LACI has not been investigated in patients treated with CRT or CSP, and there is no comparison data about the two different measurement methodologies with echocardiography. Purpose To study the effects of CRT/CSP on LACI. Methods We retrospectively collected clinical, ECG and echocardiographic data of patients treated with standard CRT or CSP. Changes between baseline and follow-up (i.e. before and after CRT/CSP) were tested for significance. Baseline features were compared with these of a control group of patients without established major cardiovascular diseases. Results We enrolled fifty-six patients (median age at first echo 78[72.5-82]years; males 70%) and 56 controls (median age 77[72.5-83]years, p=0.974; males 57%, p= 0.170). Main clinical/instrumental data are shown in Table 1 and 2. In patients treated with CRT/CSP baseline LACIv (LAVid/LV EDV) was significantly lower than in controls (31[21-44]%vs34[29-48]%, p=0.040), despite higher LAVi and LV volumes in the first group (p&amp;lt;0.0001 for both). Conversely, LACId (LAVi/TDI-a’) was significantly higher in the CRT/CSP (4.48[2.81-8.28]vs2.89[2.36-3.67]mlxsecond/cm-1, p&amp;lt;0.0001). After a median follow-up of 515[282-1326]days, patients treated with CRT/CSP showed a significant increase of both LACIv (40[29-50]%, p=0.004) and LACId (4.95[3.77-9.89], p&amp;lt;0.0001). This worsening of atrioventricular coupling was accompanied by a trending LA dilatation with significant reduction of its reservoir function compared to baseline (expansion index 0.58[0.38-1.30]vs0.43[0.29-0.58], p=0.0002), despite a tendency toward stability or improvement of LV size and systolic/diastolic parameters. Conclusions In patients treated with CRT/CSP there is a worsening of LACI over time. We can speculate that the detrimental effects of artificial pacing might not be adequately counterbalanced by CRT/CSP, or that LV and LA pathology follow alternative trajectories with different responses to treatments. Moreover, the measurement of LACId should be probably avoided in patients with conduction disorders or paced. Further larger case-control studies are needed to clarify the usefulness of LACI as a valid parameter to assess atrioventricular coupling and its changes over time in patients treated with CRT/CSP.

Left atrioventricular coupling index: association with diastolic dysfunction and prognostic implications in heart failure patients

Abstract Background Left atrioventricular coupling index (LACI), an index coupling left atrial (LA) to left ventricular (LV) volume at end-diastole (Figure 1), showed to be associated with prognosis in different clinical settings. However, the relation between LACI and LV diastolic dysfunction (DD) remains to be established. Purpose The present study aimed to investigate the association between LACI and LV DD and to assess its prognostic value in patients with heart failure (HF). Methods We retrospectively analyzed 1158 stable HF patients (mean age 66±12 years, 75% men) on optimal medical therapy (derivation cohort). Clinical and echocardiographic features were characterized across LACI tertiles. The independent prognostic value of LACI (endpoint: all-cause death/HF-hospitalization) was assessed by Cox regression and spline curve analyses. Results were validated in an external cohort of 242 HF patients. Results In the derivation cohort, the median LACI value was 0.29 (IQR:0.19-0.42). Patients in the third tertile (LACI&amp;gt;0.36) were older and presented with more advanced HF symptoms. While prevalence of grade-1 DD (ASE/EACVI classification) progressively decreased across LACI tertiles, the prevalence of grade-3 DD significantly increased (8%,23%, and 46% respectively, P&amp;lt;0.0001). A cut-off value ³0.26 identified moderate-to-severe DD with an area-under the-curve of 0.75. During follow-up (median 28 months, IQR:11-53), 407 (35%) patients reached the endpoint. On multivariable analysis, LACI was independently associated with outcomes (HR for 1-unit-increase 2.34; 95%CI 1.35-4.03; P=0.002 – Figure 2), showing incremental predictive value over the DD grading system (net reclassification improvement=0.150, P&amp;lt;0.0001). The prognostic value of LACI was consistent in the external validation cohort. Conclusions LACI is associated with DD severity and is an independent predictor of outcomes in HF patients.How to assess LACIPrognostic value of LACI in HF

Left atrioventricular coupling index is an independent associate of new-onset AF and stroke in hypertrophic cardiomyopathy: a CMR study

Abstract Background Left atrial (LA) dysfunction is an important marker of disease progression in hypertrophic cardiomyopathy (HCM). LA volumes and functional parameters are associated with new-onset atrial fibrillation (AF) and its complications including stroke. The association between left atrioventricular coupling (LACI), a parameter reflecting the contribution of the left ventricular and LA remodeling to LA dysfunction, with the occurrence of new-onset AF and stroke has not been evaluated. Aim To investigate the association between LACI and the occurrence of new-onset AF or stroke in patients with HCM. Methods In patients with an established diagnosis of HCM and cardiac magnetic resonance (CMR) data, LACI was calculated as the ratio between the LA and the LV end-diastolic volumes. New-onset AF or occurrence of stroke comprised the primary combined endpoint. Cumulative event-free survival rates for the occurrence of the primary endpoint were estimated with the population divided according to a LACI cut-off value of 40%. The association between clinical and CMR variables and the primary endpoint was assessed with univariable and multivariable Cox proportional hazard regression models. Results Of 114 patients with HCM, (mean age 54±16 years, 33 (29%) female, LV ejection fraction 67.0±8.4%), 71 patients (49%) had a LACI &amp;gt; 40% (left atrioventricular uncoupling). During a median follow-up of 4.1 (1.8-6.4) years, 19 (16.7%) patients experienced new-onset AF or stroke. Patients with preserved left atrioventricular coupling (LACI ≤ 40%) had a lower cumulative rate of events compared to those with left atrioventricular uncoupling (log-rank p=0.031, Fig. 1). LACI was independently associated with new-onset AF or stroke after adjusting by the presence of late gadolinium enhancement (LGE) sex and age (HR=23.27, p=0.016). Conclusions In patients with HCM, the presence of left atrioventricular uncoupling is independently associated with the occurrence of new-onset AF or stroke.

How different types of cardiomyopathy with hypertrophic phenotype affect left atrial remodeling and function

Abstract Background Left atrial (LA) dysfunction is a common feature in hypertrophic cardiomyopathies. How the underlying etiology and pathophysiology of different cardiomyopathies affects LA remodeling and function remains unexplored. Purpose The aim of our study is to investigate the influence of various cardiomyopathies with hypertrophic phenotype on LA remodeling and function. Methods Patients with left ventricular (LV) hypertrophic phenotype who underwent cardiac magnetic resonance (CMR) were included. A group of patients with a normal CMR was included as a control group. CMR acquisitions used for clinical indication of heart failure diagnosis and etiology were retrospectively analyzed to obtain LA reservoir, conduit, and booster strain, left atrioventricular coupling index (LACI) and LA sphericity. Differences between groups were assessed. To investigate the independent clinical associates of LA reservoir, conduit and booster strain, multivariable linear regression analyses were performed. Results A total of 375 individuals were analyzed including 321 patients diagnosed with LV hypertrophy and 54 patients with a normal CMR. Of the 321 patients with LV hypertrophy, 148 were diagnosed with hypertrophic cardiomyopathy (HCM), 35 with cardiac amyloidosis (CA), 41 with hypertensive cardiomyopathy (HTN) and 97 with severe asymptomatic aortic stenosis (AS). CMR LA characteristic and strain analysis results are summarized in Figure 1. The indexed LA end-systolic volume (iLAVmax), indexed LA end-diastolic volume (iLAVmin) and LA sphericity were larger in patients with CA when compared to other groups (all p&amp;lt;0.05). CA patients displayed more left atrioventricular uncoupling (lower LACI) when compared to individuals with HCM, HTN, AS, and controls (all p&amp;lt;0.001), while no significant differences were observed across other groups. CA patients exhibited lower LA reservoir and booster strains compared to the other groups (all p&amp;lt;0.05), whereas no significant differences were observed across other hypertrophic phenotype diseases. Age, iLAVMax and LACI were independently associated with all the three LA strain components (Figure 2, all p&amp;lt;0.05). Conclusions LA remodeling and function are affected differently across the various etiologies of LV hypertrophy. CA patients exhibit more pronounced atrial involvement, whereas those with HCM, asymptomatic AS, and HTN display similar patterns of atrial dysfunction and remodeling. Additionally, CMR-derived iLAVmax and LACI are independently correlated with LA function.

Assessment of left atrial function and left atrioventricular coupling via cardiac magnetic resonance in individuals with prediabetes and diabetes.

Assessment of left atrial (LA) function and the left atrioventricular coupling index (LACI) have recently been increasingly recognized as important indices for cardiovascular diseases associated with the presence of prediabetes and diabetes. We aimed to evaluate LA function and the LACI in patients with prediabetes and diabetes via cardiac magnetic resonance (CMR). In this retrospective study, we included 35 patients with prediabetes, 32 patients with diabetes, and 84 healthy control participants. The LACI and LA total, passive, and active emptying fractions (LATEmF, LAPEmF, and LAAEmF, respectively) were calculated. The LA reservoir, conduit, and booster pump strains (εs, εe, and εa), and peak positive, peak early negative, and peak late negative strain rates (SRs, SRe, and SRa) were obtained via CMR-feature tracking (CMR-FT). For the statistical analyses, one-way analysis of variance, the Kruskal-Wallis test, and linear regression were conducted, and Pearson's and interclass correlation coefficients were calculated. Compared with healthy control participants, patients with prediabetes or diabetes presented lower εs and εe values and a relatively preserved LACI. Patients with diabetes presented considerably reduced SRs, SRe, and LAPEmF. Elevated glycated haemoglobin (HbA1c) levels were independently associated with decreased magnitudes of εs, SRs, εe, and SRe. No significant associations were found between the LACI and the HbA1c or LA deformation parameters. We observed significant correlations between LATEmF and εs, LAPEmF and εe and between LAAEmF and εa. CMR-FT provides a potential noninvasive approach for the early detection of alterations in the LA reservoir and conduit function in individuals with prediabetes and diabetes.

Cardiovascular magnetic resonance-derived left atrioventricular coupling index as a novel prognostic marker for light-chain amyloidosis

BackgroundLeft atrioventricular coupling index (LACI) is a novel biomarker, and the prognostic value of LACI to predict cardiovascular events has been validated. The present study aimed to explore the prognostic value of LACI in patients with light-chain (AL) amyloidosis. MethodsWe prospectively enrolled 179 patients with AL amyloidosis who underwent cardiovascular magnetic resonance imaging between December 2011 and January 2020. LACI was defined as the ratio between the left atrial volume and the left ventricular volume at end-diastole. The primary endpoint was all-cause mortality. Receiver operating characteristic curve was used to identify the optimal cut-off of LACI in predicting all-cause mortality. Univariable and multivariable Cox proportional hazard models were used to assess the association of LACI and primary endpoint. ResultsDuring a median follow-up of 30 months, 118 (65.9 %) patients with all-cause mortality were documented. LACI was significantly higher in patients with primary endpoint compared to those without primary endpoint (55.4 %, interquartile range: 31.6 %–71.5 % vs. 39.4 %, interquartile range: 24.1 %–54.7 %, p = 0.001). The optimal cut-off for LACI to predict mortality was 49.3 %. In multivariate Cox regression analysis, LACI≥49.3 % (HR 1.907, 95 % CI 1.273–2.857, p = 0.002) was an independent predictor of all-cause mortality. On Kaplan-Meier analysis, patients at advanced Mayo stage (IIIa and IIIb) can be further risk stratified using LACI≥49.3 % (log-rank p = 0.035, p = 0.025). ConclusionThe LACI provides powerful independent prognostic value in AL amyloidosis. The LACI has incremental prognostic value to predict all-cause mortality over the Mayo stage in patients at the advanced Mayo stage.

Predictive value of the left atrioventricular coupling index for recurrence after radiofrequency ablation of paroxysmal atrial fibrillation

BackgroundAlthough patients with paroxysmal atrial fibrillation (PAF) are preferred to undergo catheter ablation (CA), the high possibility of recurrence following surgery is still concerning. We aimed to evaluate the ability of the left atrioventricular coupling index (LACI), which is the ratio of the left atrium end-diastolic volume to the left ventricle end-diastolic volume, to predict PAF recurrence after CA.MethodsPatients with PAF undergoing CA for the first time between January 2018 and June 2021 were admitted and grouped by recurrence within a year. LACI was measured before CA using ultrasonography. Risk factors identified by multivariable logistic regression analysis, and the area under the receiver operating characteristic (ROC) curve was used to assess the ability of LACI to predict PAF recurrence after CAP.ResultsAmong the 204 patients treated at our hospital, 164 patients were included in the research after eliminating those who were lost to follow-up. Among them, 56 individuals had recurrence following a 90-day blanking period. Recurrence is more likely in elderly patients with high blood pressure. Patients who suffered recurrence exhibited lower left atrial ejection fraction and increased LACI, left atrial volume minimum, and left atrium volume index maximum. LACI was an independent risk factor for postoperative recurrence (OR: 1.526, 95% CI: 1.325–1.757, P < 0.001), and ROC displayed remarkable predictive value [area under the curve (AUC) = 0.868].ConclusionsHigh LACI is significantly associated with postoperative recurrence in PAF patients, and LACI has incremental prognostic value to predict recurrence.

Left and right atrioventricular coupling index in patients with beta-thalassemia major.

The aim of this cross-sectional study was to investigate the relationship of left atrioventricular coupling index (LACI) and right atrioventricular coupling index (RACI) with demographics, clinical data, cardiovascular magnetic resonance findings, and cardiac complications (heart failure, arrhythmias, and pulmonary hypertension) in a cohort of patients with beta-thalassemia major (β-TM). We evaluated 292 β-TM patients (151 females, 36.72 ± 11.76years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. Moreover, we assessed 32 sex- and age-matched healthy controls (12 females, mean age 40.78 ± 14.35years). LACI was determined by calculating the ratio of the left atrium end-diastolic volume to the left ventricle end-diastolic volume, while RACI was defined by calculating the ratio of the right atrium end-diastolic volume to the right ventricle end-diastolic volume. Compared to healthy control, β-TM demonstrated increased LACI (22.99 ± 13.58% vs. 16.05 ± 5.28%; p < 0.0001) and RACI (27.84 ± 10.30% vs. 17.06 ± 5.03%; p < 0.0001). Aging, diabetes, splenectomy, and the presence of late gadolinium enhancement (LGE) showed a significant positive association with both LACI and RACI. In stepwise regression analysis, the presence of LGE was found to be an independent predictor of both impaired LACI and RACI (β coefficient = 0.244, p < 0.0001 and β coefficient = 0.218, p = 0.003; respectively). LACI and RACI were not correlated with myocardial iron overload. Patients with cardiac complications had significantly higher LACI and RACI than patients without cardiac complications. In patients with β-TM, LACI and RACI were significantly associated with the presence of LV LGE. In addition, patients with cardiac complications had impaired LACI and RACI.

Left Atrial Strain During Exercise: A Window to Atrioventricular Coupling in Heart Failure.

Left Atrial Strain During Exercise: A Window to Atrioventricular Coupling in Heart Failure.

Left Atrioventricular Coupling Index: A Novel Diastolic Parameter to Refine Prognosis in Heart Failure

Left atrioventricular coupling index (LACI), an index coupling left atrial to left ventricular (LV) volume at end-diastole, has been shown to be associated with prognosis in different clinical settings. However, the relation between LACI and LV diastolic dysfunction (DD) remains to be established. The aims of the present study were to investigate the association between LACI and LV DD and to assess its prognostic value in patients with heart failure (HF). A total of 1,158 patients with HF in stable condition, on optimal medical therapy, were retrospectively analyzed (derivation cohort). Clinical and echocardiographic features were characterized across LACI tertiles. The independent prognostic value of LACI (end point: all-cause death or HF hospitalization) was assessed using Cox regression. Results were validated in an external cohort of 242 patients with HF. In the derivation cohort, the median LACI value was 0.29 (interquartile range, 0.19-0.42). Patients in the third tertile (LACI>0.36) were older and presented with more advanced HF symptoms. Although the prevalence of grade 1 DD (American Society of Echocardiography/European Association of Cardiovascular Imaging classification) progressively decreased across LACI tertiles, the prevalence of grade 3 DD significantly increased (8%, 23%, and 46%, respectively; P<.0001). A cutoff value of ≥0.26 identified moderate to severe DD with an area under the curve of 0.75. During follow-up (median, 28months; interquartile range, 11-53 months), 407 patients (35%) reached the end point. On multivariable analysis, LACI was independently associated with outcomes (hazard ratio for a 1-SD increase, 1.16; 95% CI, 1.06-1.28; P=.002), showing incremental predictive value over the DD grading system (net reclassification improvement=0.150, P<.0001). The prognostic value of LACI was consistent in the external validation cohort. LACI is associated with DD severity and is an independent predictor of outcomes in patients with HF.

CMR-based cardiac phenotyping in different forms of heart failure

Heart failure (HF) is a heterogenous disease requiring precise diagnostics and knowledge of pathophysiological processes. Since structural and functional imaging data are scarce we hypothesized that cardiac magnetic resonance (CMR)-based analyses would provide accurate characterization and mechanistic insights into different HF groups comprising preserved (HFpEF), mid-range (HFmrEF) and reduced ejection fraction (HFrEF). 22 HFpEF, 17 HFmrEF and 15 HFrEF patients as well as 19 healthy volunteers were included. CMR image assessment contained left atrial (LA) and left ventricular (LV) volumetric evaluation as well as left atrioventricular coupling index (LACI). Furthermore, CMR feature-tracking included LV and LA strain in terms of reservoir (Es), conduit (Ee) and active boosterpump (Ea) function. CMR-based tissue characterization comprised T1 mapping as well as late-gadolinium enhancement (LGE) analyses. HFpEF patients showed predominant atrial impairment (Es 20.8%vs.25.4%, p = 0.02 and Ee 8.3%vs.13.5%, p = 0.001) and increased LACI compared to healthy controls (14.5%vs.23.3%, p = 0.004). Patients with HFmrEF showed LV enlargement but mostly preserved LA function with a compensatory increase in LA boosterpump (LA Ea: 15.0%, p = 0.049). In HFrEF LA and LV functional impairment was documented (Es: 14.2%, Ee: 5.4% p < 0.001 respectively; Ea: 8.8%, p = 0.02). This was paralleled by non-invasively assessed progressive fibrosis (T1 mapping and LGE; HFrEF > HFmrEF > HFpEF). CMR-imaging reveals insights into HF phenotypes with mainly atrial affection in HFpEF, ventricular affection with atrial compensation in HFmrEF and global impairment in HFrEF paralleled by progressive LV fibrosis. These data suggest a necessity for a personalized HF management based on imaging findings for future optimized patient management.

DIASTOLIC DYSFUNCTION EVALUATION IN CARDIAC AMYLOIDOSIS: BEYOND TRADITIONAL PARAMETERS TO DISCRIMINATE BETWEEN TRUE HEART FAILURE WITH PRESERVED EJECTION FRACTION AND MIMICS

Abstract Background Diastolic dysfunction in cardiac amyloidosis (CA), according to current guidelines, can be classified using mitral flow velocities, mitral annular e’ velocity, E/e’ ratio, tricuspid regurgitation jet and left atrial (LA) maximal volume. However, LA minimal volume and the ratio between LA and left ventricular (LV) volumes at end–diastole, known as left atrio–ventricular coupling index (LACI), have recently been proposed to refine prognosis and peak atrial longitudinal strain (PALS) has been demonstrated to better stratify diastolic dysfunction. Aim of the Study To evaluate, in patients with CA: 1) the role of LACI as marker of LV diastolic dysfunction; 2) whether LACI could discriminate cardiomyopathy from normal cardiac function; 3) whether LACI and/or PALS could help discriminate between true heart failure with preserved ejection fraction (HFpEF) and amyloidotic cardiomyopathy (HFpEF–mimic). Methods We retrospectively analyzed 63 patients with CA and compared them with 80 true HFpEF patients and 70 healthy people; echocardiography was performed at the time of the diagnosis and diastolic function was characterized according to current guidelines. Results In patients with CA, LACI significantly increased as diastolic dysfunction worsened (P for trend &amp;lt; 0.0001) and significantly correlated with LV filling pressures estimated by E/e’ ratio (beta = 0.65, P &amp;lt; 0.0001) and pulmonary artery systolic pressure (beta = 0.63, P &amp;lt; 0.0001). LACI, after adjustment for age, gender and body mass index (BMI), was significantly higher in CA [0.62 (95%CI 0.52–0.70)] and in HFpEF [0.61 (95%CI 0.55–0.68)] than in controls [0.29 (95%CI 0.19–0.39)], while the difference between the two diseased populations was not statistically significant; a cut–off value of 0.45 was able to discriminate between controls and diseased patients (sensitivity = 95%, specificity = 94%, area under ROC curve = 0.98). PALS, after adjustment for age, gender and BMI, was significantly lower in CA [11.1 (95%CI 8.4–13.8%) and 8.4 (95%CI 3.5–13.3%) respectively in ATTR and AL] than in HFpEF [17.4 (95%CI 15.6–19.3%)], and a cut–off value of 9.9% was able to discriminate between them (sensitivity = 89%, specificity = 73%, area under ROC curve = 0.86). Conclusions LACI is a novel index able to discriminate between normal and diseased patients. In CA, it shows good correlation with diastolic dysfunction and LV filling pressures. PALS can be used to discriminate between true HFpEF and CA.

NOVEL INTEGRATED IMAGING PARAMETERS FOR RISK STRATIFICATION OF ATRIAL FIBRILLATION IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY

Abstract Background Atrial fibrillation (AF) impacts prognosis of hypertrophic cardiomyopathy (HCM) by promoting progressive heart failure (HF) and increasing risk of stroke. Over the past years, several indexes and methods to predict AF among HCM patients have been proposed. However, they are limited by a lack of accuracy. Aims of our study was to evaluate the role of new echocardiographic parameters in predicting new onset of AF and to validate them by cardiac magnetic resonance (CMR). Methods and Results We analyzed clinical and imaging data of 141 HCM patients in sinus rhythm who underwent first evaluation at our center (51.2 ± 17.3 years, mean follow up 5.3 ± 3 years). Main parameters analyzed were left atrium (LA) end–diastolic volume (LAV min), end–systolic volume (LAVmax), LA ejection fraction (LAEF), left atrioventricular coupling index (LACI), and LA diameter (LAD). LACI was defined by the LAVmin divided by the LV end–diastolic volume (LVEDV); this parameter was assessed in previous studies as a good detector of early atrial remodeling and impaired LV compliance. 35 patients developed new–onset AF (after a mean period of 4 ± 3.2 years). At the baseline evaluation, LACI, LAD, and LAVmin showed to be significantly greater in patients who developed AF compared to patients who did not. At CMR, LACI &amp;gt;44% accurately predicted new–onset AF (sensitivity 85%, specificity 70%; AUC 0.81). LACI by ETT showed similar accuracy (AUC 0.75) and was superior to that shown by LAD (AUC 0.71) (Figure 1). Patients who did not develop AF had significantly higher LAEF at ETT (49.3 ± 11% vs 37 ± 9.6%; p &amp;lt; 0.0001). CMR analysis confirmed this result. LAEF &amp;gt;43% was a good predictor of AF free survival (log rank&amp;lt;0.001). Conversely, at a multivariate analysis, LAFE &amp;lt;43% by ETT was independently associated with AF occurrence (OR 4.5, 95% CI 1.4–13.7) (Figure 2). 11 patients experienced death or heart transplant (HTx). Higher values of LACI and LAVmin and lower values of LAEF were found to be associated the composite outcome of death or HTx. LACI&amp;gt;60% predicted the composite of death or HTx with good accuracy (AUC 0.74) (Figure 3). Conclusions LACI and LAEF showed to improve accuracy in predicting the new onset of AF in HCM patients without severe LA dilatation (LAD&amp;gt;45mm). Higher LACI and Lower LAEF (namely &amp;lt;43%) identify patients at higher risk of new onset AF, and, therefore, worthy of a more strict follow–up.

The Atrioventricular Coupling in Heart Failure: Pathophysiological and Therapeutic Aspects.

For a long time, the study of heart failure focused on single heart chamber disease. There is, instead, growing attention on the interplay between the atria and the ventricles during the cardiac cycle and on the consequences of an altered chamber coupling on global heart performance and heart failure. This review aimed to explore the principles of atrioventricular (AV) function and coupling of the left heart and the consequences that their disruption could have in several diseases. Furthermore, we will examine echocardiographic tips for analyzing the chamber function and the AV coupling. Finally, we will explore the most recent pharmacological acquisitions and the device therapies we have for use.

Incremental Prognostic Value of Left Atrial Strain in Patients With Suspected Myocarditis and Preserved Left Ventricular Ejection Fraction.

Analysis of left atrial (LA) strain and left atrioventricular coupling index (LACI) have prognostic value in cardiovascular diseases. However, the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved left ventricular ejection fraction (LVEF) is unclear. To investigate the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved LVEF in comparison with conventional MRI outcome predictors. Retrospective. One hundred sixty-five patients with clinically suspected myocarditis and preserved LVEF with available follow-up data. Steady-state free precession cine and phase-sensitive inversion recovery segmented gradient echo late gadolinium enhancement sequences at 3.0 T. Left ventricular (LV) and LA strain were evaluated using feature tracking. LACI was calculated as the ratio of LA and LV volumes at LV end-diastole. Patients were followed-up with the primary endpoint being major adverse cardiovascular events (MACE). Independent-samples t-test and Mann-Whitney U test to compare patients with and without MACE, receiver operating characteristic (ROC) curve analysis to define high/low risk groups, Kaplan-Meier survival analysis and Cox proportional hazards regression to assess prognosis. A P value of <0.05 was considered statistically significant. The associations of LV strain parameters (including global radial, circumferential, and longitudinal strain) and LACI with MACE were not significant (P = 0.511, 0.108, 0.148, and 0.847, respectively). An optimal LA conduit strain (Ԑe) cutoff value of 10.4% was identified to best classify patients into low- and high-risk groups. Only Ԑe was significantly associated with MACE in both univariable (hazards ratio [HR] 0.936, 95% confidence interval [CI] 0.884-0.991) and multivariable Cox survival analyses (HR 0.937, 95% CI 0.884-0.994). LA conduit strain has prognostic value in patients with suspected myocarditis and preserved LVEF, incremental to conventional MRI outcome predictors, whereas LACI was not associated with MACE occurrence. 3 TECHNICAL EFFICACY: Stage 2.

Impact of Type 2 Diabetes Mellitus on Left Atrioventricular Coupling and Left Atrial Deformation in Patients with Essential Hypertension: An MRI Feature Tracking Study.

Hypertension (HTN) and type 2 diabetes mellitus (T2DM) are both associated with left ventricular (LV) and left atrial (LA) structural and functional abnormalities; however, the relationship between the left atrium and ventricle in this population is unclear. To identify differences between hypertensive patients with and without T2DM as the basis for further investigation the atrioventricular coupling relationship. Cross-sectional, retrospective study. 89 hypertensive patients without T2DM [HTN (T2DM-)] (age: 58.4 +/- 11.9 years, 48 male), 62 hypertensive patients with T2DM [HTN (T2DM+)] (age: 58.5 +/- 9.1 years, 32 male) and 70 matched controls (age: 55.0 +/- 9.6 years, 37 male). 2D balanced steady-state free precession cine sequence at 3.0 T. LA reservoir, conduit, and booster strain (εs, εe, and εa) and strain rate (SRs, SRe, and SRa), LV radial, circumferential and longitudinal peak strain (PS) and peak systolic strain rate and peak diastolic strain rate (PSSR and PDSR) were derived from LA and LV cine images and compared between groups. Chi-square or Fisher's exact test, one-way analysis of variance, analysis of covariance, Pearson's correlation, multivariable linear regression analysis, and intraclass correlation coefficient. A P value <0.05 was considered significant. Compared with controls, εs, εe, SRe and PS-longitudinal, PDSR-radial, and PDSR-longitudinal were significantly lower in HTN (T2DM-) group, and they were even lower in HTN (T2DM+) group than in both controls and HTN (T2DM-) group. SRs, εa, SRa, as well as PS-radial, PS-circumferential, PSSR-radial, and PSSR-circumferential were significantly lower in HTN (T2DM+) compared with controls. Multivariable regression analyses demonstrated that: T2DM and PS-circumferential and PS-longitudinal (β = -4.026, -0.486, and -0.670, respectively) were significantly associated with εs; T2DM and PDSR-radial and PDSR-circumferential were significantly associated with εe (β = -3.406, -3.352, and -6.290, respectively); T2DM and PDSR-radial were significantly associated with SRe (β = 0.371 and 0.270, respectively); T2DM and PDSR-longitudinal were significantly associated with εa (β = -1.831 and 5.215, respectively); and PDSR-longitudinal was significantly associated with SRa (β = 1.07). In hypertensive patients, there was severer LA dysfunction in those with coexisting T2DM, which may be associated with more severe LV dysfunction and suggests adverse atrioventricular coupling. 3. Stage 3.

Effect of Metabolic Syndrome on Left Atrial and Left Ventricular Deformation and Atrioventricular Interactions in Patients With Myocardial Infarction.

Metabolic syndrome (MetS) is associated with worse prognosis in patients with myocardial infarction (MI). However, it is unclear how MetS in MI patients is associated with left atrial (LA) and left ventricular (LV) deformation. To determine the effect of MetS on LA and LV deformation and atrioventricular interactions in MI patients. Retrospective. One hundred eighty-one MI patients (73 MetS+ and 108 MetS-), 107 age- and sex-matched controls (49 MetS+ and 58 MetS-). 3.0 T/balanced steady-state free precession (SSFP)/segmented phase-sensitive inversion recovery SSFP sequence. LA strain and strain rates (reservoir, conduit, and active), left atrioventricular coupling index (LACI), and LV geometry and radial, circumferential and longitudinal global peak strains (PS) were compared among groups. Two-way analysis of variance, Spearman and Pearson's correlation coefficients, and multivariable linear regression analysis. P value <0.05 indicated statistical significance. Compared with controls, the MI patients with or without MetS showed impaired LA function (reservoir, conduit, and active) and LV deformation (radial, circumferential, and longitudinal PS) and higher LACI. The MetS+ group had lower LA reservoir and conduit function and LV deformationthan MetS- group. The MetS-MI interaction was not statistically significant. Furthermore, multivariable linear regression showed that MetS was independently associated with LA and LV deformation (β = -0.181 to -0.209) in MI patients; LA function was independently associated with LV circumferential PS (β = 0.230 to 0.394) and longitudinal PS (β = 0.189 to 0.420), and LA passive strain and strain rate were negatively associated with LV mass (β = -0.178 and -0.298). MetS may be associated with the LA and LV dysfunction in MI patients. Impaired LV deformation and LV hypertrophy are independently associated with LA dysfunction in MI patients, and the MI patients have higher LACI than controls, suggesting atrioventricular interaction alterations. 4 TECHNICAL EFFICACY: 3.

Evaluation of the relationship between left atrial stiffness, left ventricular stiffness, and left atrioventricular coupling index in type 2 diabetes patients: a speckle tracking echocardiography study.

Cardiovascular complications are a leading cause of mortality and disability in individuals with diabetes mellitus (DM). Moreover, DM can directly impact the structure and function of cardiac muscle. We conducted a study to evaluate cardiac stiffness in DM patients in both the left atrium (LA) and left ventricle (LV), as well as to assess the impact of DM on the synchronization of the LA and LV, particularly within the Vietnamese population, utilizing speckle tracking echocardiography (STE). We studied 111 research subjects divided into two groups comprising 52 patients with DM and 59 healthy individuals. All the subjects provided relevant clinical information, and echocardiography was performed to assess the indices of LA stiffness, LV stiffness, and left atrioventricular coupling index (LACI). Our study indicated that DM patients exhibited greater LA and LV stiffness than control patients. The LACI (%) in the DM group was also greater than that in the control group (17.12% ± 6.72% vs. 12.28% ± 3.96%, respectively; p < 0.001). The LACI was positively correlated with the LA and LV stiffness indices. Decreased levels of LV GLS, adjusted for age, sex, blood pressure, and BMI, have emerged as identified risk factors for DM. LA stiffness, LV stiffness, and the LACI are greater in DM patients than in normal individuals.