Sex Differences in Aortic Stenosis: From the Pathophysiology to the Intervention, Current Challenges, and Future Perspectives

Calcific aortic stenosis (AS) is a major cause of morbidity and mortality in high-income countries. AS presents sex-specific features impacting pathophysiology, outcomes, and management strategies. In women, AS often manifests with a high valvular fibrotic burden, small valvular annuli, concentric left ventricular (LV) remodeling/hypertrophy, and, frequently, supernormal LV ejection fraction coupled with diastolic dysfunction. Paradoxical low-flow low-gradient AS epitomizes these traits, posing significant challenges post-aortic valve replacement due to limited positive remodeling and significant risk of patient-prosthesis mismatch. Conversely, men present more commonly with LV dilatation and dysfunction, indicating the phenotype of classical low-flow low-gradient AS, i.e., with decreased LV ejection fraction. However, these distinctions have not been fully incorporated into guidelines for AS management. The only treatment for AS is aortic valve replacement; women are frequently referred late, leading to increased heart damage caused by AS. Therefore, it is important to reassess surgical planning and timing to minimize irreversible cardiac damage in women. The integrity and the consideration of sex differences in the management of AS is critical. Further research, including sufficient representation of women, is needed to investigate these differences and to develop individualized, sex-specific management strategies.

Prognostic value of left ventricular and left atrial strain imaging in moderate to severe aortic stenosis: Insights from an Asian population

BACKGROUND

Data regarding the prognostic value of left atrial (LA) strain in aortic stenosis (AS) is scarce, especially in Asian population and moderate AS.

METHOD

Left ventricular global longitudinal strain (LVGLS), LA reservoir strain (LASr), conduit strain (LAScd), and contractile strain (LASct) were measured using automated speckle-tracking echocardiography in consecutive patients with moderate or severe AS. The primary endpoint was a composite of all-cause death (ACD) and major adverse cardiovascular events (MACE; myocardial infarction, syncope, and heart failure hospitalization).

RESULTS

Of 712 patients (mean age, 78 ± 12 years; 370 [52%] moderate AS; 342 [48%] severe AS), average LV ejection fraction (LVEF) was 68 with SD of 12%. At a median follow-up of 18 months (interquartile range, 11-26 months), the primary endpoint occurred in 93 patients (60 deaths and 35 MACEs) and 221 patients underwent surgical or transcatheter aortic valve replacement (AVR). In the entire cohort, separate multivariable models adjusted for age, Charlson index, symptomatic status, time-dependent AVR, AS-severity, LA volume index and LVEF demonstrated that only LASr was associated with MACE+ACD (Hazard ratio, 0.97; P = 0.014). Subgroup analysis for MACE+ACD demonstrated consistent prognostication for LASr in moderate and severe AS; LVGLS was prognostic only in severe AS (all P ≤ 0.023). The optimal MACE+ACD cutoff for LASr from spline curves was 21.3%. Adjusted Kaplan-Meier curves demonstrated better event-free survival in patients with LASr >21.3% versus those with LASr ≤21.3% (P = 0.04).

CONCLUSIONS

In both moderate and severe AS, only LASr robustly predicted outcomes; thus, including LASr in the AS staging algorithm should be considered.

Peak atrial longitudinal strain and risk stratification in moderate and severe aortic stenosis

AIMS

We sought to investigate the association of left atrial strain with the outcome in a large cohort of patients with at least moderate aortic stenosis (AS).

METHODS AND RESULTS

We analysed 467 patients (mean age 80.6 ± 8.2 years; 51% men) with at least moderate AS and sinus rhythm. The primary study endpoint was the composite of all-cause mortality and hospitalizations for heart failure. After a median follow-up of 19.2 (inter-quartile range 12.5-24.4) months, 96 events occurred. Using the receiver operator characteristic curve analysis, the cut-off value of peak atrial longitudinal strain (PALS) more strongly associated with outcome was <16% {area under the curve (AUC) 0.70 [95% confidence interval (CI): 0.63-0.78], P < 0.001}. The Kaplan-Meier curves demonstrated a higher rate of events for patients with PALS < 16% (log-rank P < 0.001). On multivariable analysis, PALS [adjusted HR (aHR) 0.95 (95% CI 0.91-0.99), P = 0.017] and age were the only variables independently associated with the combined endpoint. PALS provided incremental prognostic value over left ventricular (LV) global longitudinal strain, LV ejection fraction, and right ventricular function. Subgroup analysis revealed that impaired PALS was also independently associated with outcome in the subgroups of paucisymptomatic patients [aHR 0.98 (95% CI 0.97-0.98), P = 0.048], moderate AS [aHR 0.92, (95% CI 0.86-0.98), P = 0.016], and low-flow AS [aHR 0.90 (95% CI 0.83-0.98), P = 0.020].

CONCLUSION

In our patients with at least moderate AS, PALS was independently associated with outcome. In asymptomatic patients, PALS could be a potential marker of sub-clinical damage, leading to better risk stratification and, potentially, earlier treatment.

Prognostic value of left atrial strain in aortic stenosis: A systematic review

PURPOSE

Aortic stenosis (AS) is a common valvular heart disease with high morbidity and mortality. Recently, the association between peak atrial longitudinal strain (PALS) and AS clinical outcomes has been identified. This systematic review evaluates the prognostic value of PALS for adverse events in AS.

METHODS

We performed a systematic literature review to identify clinical studies that evaluated Speckle-Tracking Echocardiography (STE)-derived PALS to predict adverse outcomes in patients with AS. We excluded studies that compared echocardiography to computed tomography and studies that focused on diseases other than AS.

RESULTS

We included 18 studies reporting on 2660 patients. Patients with symptomatic AS had decreased PALS when compared to patients with asymptomatic AS. Patients with AS who had adverse events had decreased PALS when compared to patients with AS with no events. Each unit increase of PALS was independently associated with decreased risk for the primary endpoint. PALS cut-off values were associated with increased risk for the primary endpoint.

CONCLUSION

This systematic review suggests PALS as an independent predictor for cardiovascular events in patients with AS and highlights the importance of evaluating LA mechanics for AS prognosis.

The influence of transcatheter aortic valve replacement on left atrial mechanics: a systematic review and meta-analysis

Aims

The morphology and function of the left atrium (LA) are intimately tied to left ventricular loading conditions. Data pertaining to the effect of transcatheter aortic valve replacement (TAVR) on LA function and geometry are scarce. The aim of the study was to quantify associations between TAVR and LA remodelling by pooling available data from published observational studies.

Methods and results

A systematic review and meta-analysis were performed. Studies reporting serial LA speckle-tracking echocardiographic (STE) data, before and after TAVR, were included. Other outcome data included LA area and indexed volume (LAVi) and standard chamber measurements. Outcomes were stratified by timing of follow-up echocardiography: early (<6 months) or late (≥6 months). Twelve studies were included, comprising 1066 patients. The mean reduction in LAVi was 2.72 mL/m2 [95% confidence interval (CI) 1.37-4.06, P < 0.01]. LA reservoir function improved overall by a mean difference (MD) of 3.71% (95% CI 1.82-5.6, P < 0.01), although there was significant heterogeneity within the pooled studies (I 2 = 87.3%). Significant improvement in reservoir strain was seen in both early follow-up (MD 3.1%, P < 0.01) and late follow-up studies (MD 4.48%, P = 0.03), but heterogeneity remained high (I 2 = 65.23 and 94.4%, respectively). Six studies reported a change in LA contractile function, which recovered in the early follow-up studies (MD 2.26, P < 0.01), but not in the late group (MD 1.41, P = 0.05). Pooled improvement in LA booster function was 1.96% (95% CI 1.11-2.8, P < 0.01).

Conclusion

TAVR is associated with significant negative LA remodelling, and an improvement in LA mechanics, quantified by STE. The prognostic implications of these findings require further study.

Prognostic significance and clinical utility of left atrial reservoir strain in transcatheter aortic valve replacement

AIMS

Patients with diastolic dysfunction (DD) experience worse outcomes after transcatheter aortic valve replacement (TAVR). We investigated the prognostic value and clinical utility of left atrial reservoir strain (LARS) in patients undergoing TAVR for aortic stenosis (AS).

METHODS AND RESULTS

All consecutive patients undergoing TAVR between January 2018 and December 2018 were included if discharge echocardiography and follow-up were available. LARS was derived from 2D-speckle-tracking. Patients were grouped into three tertiles according to LARS. DD was analysed using the ASE/EACVI-algorithm. The primary outcome was a composite of all-cause death and readmission for worsening heart failure 12 months after TAVR. Overall, 606 patients were available [age 80 years, interquartile range (IQR) 77-84], including 53% women. Median LARS was 13.0% (IQR 8.4-18.3). Patients were classified by LARS tertiles [mildly impaired 21.4% (IQR 18.3-24.5), moderately impaired 13.0% (IQR 11.3-14.6), severely impaired 7.1% (IQR 5.4-8.4), P < 0.0001]. The primary outcome occurred more often in patients with impaired LARS (mildly impaired 7.4%, moderately impaired 13.4%, and severely impaired 25.7%, P < 0.0001). On adjusted multivariable Cox regression analysis, LARS tertiles [hazard ratio (HR) 0.62, 95% confidence interval (CI) 0.44-0.86, P = 0.005] and higher degree of tricuspid regurgitation (HR 1.82, 95% CI 1.23-2.98, P = 0.003) were the only significant predictors of the primary endpoint. Importantly, DD was unavailable in 56% of patients, but LARS assessment allowed for reliable prognostication regarding the primary endpoint in subgroups without DD assessment (HR 0.64, 95% CI 0.47-0.87, P = 0.003).

CONCLUSION

Impaired LARS is independently associated with worse outcomes in patients undergoing TAVR. LARS allows for risk stratification at discharge even in patients where DD cannot be assessed by conventional echocardiographic means.

Left atrial pump strain predicts long-term survival after transcatheter aortic valve implantation

BACKGROUND

This study aims at investigating left atrial (LA) deformation by left atrial reservoir (LARS) and pump strain (LAPS) and its implications for long-term survival in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI).

METHODS

Speckle tracking echocardiography was performed in 198 patients with severe AS undergoing TAVI. Association of strain parameters with cardiovascular mortality was determined.

RESULTS

Over a follow-up time of 5 years, 49 patients (24.7%) died. LAPS was more impaired in non-survivors than survivors (P = 0.010), whereas no difference was found for LARS (P = 0.114), LA ejection fraction (P = 0.241), and LA volume index (P = 0.292). Kaplan-Meier analyses yielded a reduced survival probability according to the optimal threshold for LAPS (P = 0.002). A more impaired LAPS was associated with increased mortality risk (HR 1.12 [95% CI 1.02-1.22]; P = 0.014) independent of LVEF, LAVI, age, and sex. Addition of LAPS improved multivariable echocardiographic (LVEF, LAVI) and clinical (age, sex) models with potential incremental value for mortality prediction (P = 0.013 and P = 0.031, respectively). In contrast, LARS and LAVI were not associated with mortality.

CONCLUSIONS

In patients undergoing aortic valve replacement for severe AS, LAPS was impaired in patients dying during long-term follow-up after TAVI, differentiated survivors from non-survivors, was independently associated with long-term mortality, and yielded potential incremental value for survival prediction after TAVI. LAPS seems useful for risk stratification in severe AS and timely valve replacement.

Atrial Cardiomyopathy in Valvular Heart Disease: From Molecular Biology to Clinical Perspectives

This review discusses the evolving topic of atrial cardiomyopathy concerning valvular heart disease. The pathogenesis of atrial cardiomyopathy involves multiple factors, such as valvular disease leading to atrial structural and functional remodeling due to pressure and volume overload. Atrial enlargement and dysfunction can trigger atrial tachyarrhythmia. The complex interaction between valvular disease and atrial cardiomyopathy creates a vicious cycle of aggravating atrial enlargement, dysfunction, and valvular disease severity. Furthermore, atrial remodeling and arrhythmia can predispose to atrial thrombus formation and stroke. The underlying pathomechanism of atrial myopathy involves molecular, cellular, and subcellular alterations resulting in chronic inflammation, atrial fibrosis, and electrophysiological changes. Atrial dysfunction has emerged as an essential determinant of outcomes in valvular disease and heart failure. Despite its predictive value, the detection of atrial fibrosis and dysfunction is challenging and is not included in the clinical routine. Transthoracic echocardiography and cardiac magnetic resonance imaging are the main diagnostic tools for atrial cardiomyopathy. Recently published data have revealed that both left atrial volumes and functional parameters are independent predictors of cardiovascular events in valvular disease. The integration of atrial function assessment in clinical practice might help in early cardiovascular risk estimation, promoting early therapeutic intervention in valvular disease.

Evaluation of the relationship between left atrial strain and exercise tolerance in patients with hypertrophic cardiomyopathy by treadmill stress echocardiography

Objective

The aim of this study is to evaluate the left atrial strain (LAS) in patients with hypertrophic cardiomyopathy (HCM) by treadmill exercise stress echocardiography, combined with three-dimensional speckle tracking technology, for predicting exercise tolerance.

Methods

A total of 97 patients with HCM who underwent treadmill exercise stress echocardiography were recruited in Sichuan Provincial People's Hospital between January 2018 and January 2021, and 30 control subjects were selected to be included in the normal group. HCM patients with their metabolic equivalents (METS) ≤ 6.0 were included in the HCM-1 group, while those with METS > 6.0 were included in the HCM-2 group. The LAS and exercise tolerance were analyzed. The ultrasound parameters that could predict a decrease in exercise tolerance were screened, and a predictive model was constructed.

Results

It was found that METS, Rest-LASr, Rest-LAScd, and Rest-LASct were significantly lower in HCM patients than those in normal controls. There was a significant difference in age, Target_HR, LVMI, LAVI, E/e'-Rest, E/e'-Peak, Rest-LASr, Rest-LAScd, and Rest-LASct between the HCM-1 and the HCM-2 groups. LASr is an independent resting echocardiographic predictor of METS ≤ 6.0. LASr remained significant for predicting different subtypes (AHCM, asymmetric HCM, and obstructive HCM). Rest-LASr (AUC 0.990) was better at predicting METS ≤ 6.0 than Peak-E/e' (AUC 0.753). A multivariate model (LASr + Age + Target_HR) was established for METS prediction.

Conclusion

Left atrial reservoir strain (LASr) has the strongest association with METS ≤ 6.0. The LASr is an independent resting predictor of METS ≤ 6.0 and has a good performance record in predicting different subtypes of HCM. Compared with the traditional parameters, Peak-E/e' and Rest-E/e', Rest-LASr is the best predictor. Rest-LASr can serve as a reliable method for HCM patients who are unable to undergo exercise testing but require an urgent evaluation of their METS, which provides a basis for clinical treatment decision-making and treatment effect evaluation.

Echocardiographic Evaluation after Transcatheter Aortic Valve Implantation: A Comprehensive Review

Transcatheter aortic valve implantation (TAVI) is an increasingly popular treatment option for patients with severe aortic stenosis. Recent advancements in technology and imaging tools have significantly contributed to the success of TAVI procedures. Echocardiography plays a pivotal role in the evaluation of TAVI patients, both before and after the procedure. This review aims to provide an overview of the most recent technical advancements in echocardiography and their use in the follow-up of TAVI patients. In particular, the focus will be on the examination of the influence of TAVI on left and right ventricular function, which is frequently accompanied by other structural and functional alterations. Echocardiography has proven to be key also in detecting valve deterioration during extended follow-up. This review will provide valuable insights into the technical advancements in echocardiography and their role in the follow-up of TAVI patients.

Impact of left atrial and diastolic ventricular dysfunction on mortality in patients with aortic stenosis

BACKGROUND

Diastolic dysfunction (DD) is common in severe aortic stenosis (AS) and preserved left ventricular ejection fraction (LVEF≥50%).

AIM

To determine the impact of American Society of Echocardiography/European Association of Cardiovascular Imaging-recommended DD grading and left atrial strain on mortality in a cohort of patients with severe AS and preserved LVEF.

METHODS

We studied patients with severe AS (aortic valve area indexed<0.6 cm²/m² and/or aortic valve area<1cm²), LVEF≥50% and no or mild AS-related symptoms. The endpoint was all-cause mortality.

RESULTS

A total of 387 patients (median age 76years; 53% women) were studied. During a median follow-up of 57 (interquartile range 37; 83) months, 158 patients died. After adjustment for prognostic factors, patients with grade II or III DD had an increased mortality risk versus patients with grade I DD (adjusted hazard ratio (aHR) 1.62, 95% confidence interval (CI) 1.11-2.38; P=0.013; aHR 4.73, 95% CI 2.49-8.99; P<0.001; respectively). Adding peak atrial longitudinal strain (PALS)≤14% to a multivariable model including DD grade improved predictive performance, with better global model fit, reclassification and discrimination. Patients with grade III DD or grade II DD+PALS≤14% displayed an increased mortality risk versus patients with grade I DD+PALS>14% (aHR 4.17, 95% CI 2.46-7.06; P<0.0001). Those with grade I DD+PALS≤14% or grade II DD+PALS>14% were at intermediate risk (aHR 1.63, 95% CI 1.07-2.49; P=0.024).

CONCLUSIONS

Our results demonstrate the strong relationship between DD and mortality in patients with severe AS and preserved LVEF. Patients with grade III or grade II DD and impaired PALS are at very high risk. These data demonstrate the importance of a comprehensive assessment of diastolic function in patients with severe AS.

Feature-tracking computed tomography left atrial strain and long-term survival after transcatheter aortic valve implantation

AIMS

Aortic stenosis (AS) induces left atrial (LA) remodelling through the increase of left ventricular (LV) filling pressures. Peak LA longitudinal strain (PALS), reflecting LA reservoir function, has been proposed as a prognostic marker in patients with AS. Feature-tracking (FT) multi-detector computed tomography (MDCT) allows assessment of LA strain from MDCT data. The aim of this study is to investigate the association between PALS using FT MDCT and survival in patients with severe AS who underwent transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

A total of 376 patients (mean age 80 ± 7 years, 53% male) who underwent MDCT before TAVI and had suitable data for assessment of PALS using dedicated FT software, were included. The patients were classified into four groups according to PALS quartiles; PALS > 19.3% (Q1, highest reservoir function), 15.0-19.3% (Q2), 9.1-14.9% (Q3), and ≤9.0% (Q4, lowest reservoir function). The primary outcome was all-cause mortality. During a median of 45 (22-68) months follow-up, 148 patients (39%) died. On multivariable Cox regression analysis, PALS was independently associated with all-cause mortality [hazard ratio (HR): 1.044, 95% confidence interval (CI): 1.012-1.076, P = 0.006]. Compared with patients in Q1, patients in Q3 and Q4 were associated with higher risk of mortality after TAVI [HR: 2.262 (95% CI: 1.335-3.832), P = 0.002 for Q3, HR: 3.116 (95% CI: 1.864-5.210), P < 0.001 for Q4].

CONCLUSION

PALS assessed with FT MDCT is independently associated with all-cause mortality after TAVI.

Prognostic Value of Left Atrial Reservoir Strain in Left Ventricular Myocardial Noncompaction: A 3.0 T Cardiac Magnetic Resonance Feature Tracking Study

BACKGROUND

The relationship of left atrial (LA) strain to high-risk heart failure (HF) events in patients with left ventricular myocardial noncompaction (LVNC) remains to be thoroughly investigated.

PURPOSE

To evaluate the LA performance in patients with LVNC, and to investigate the prognostic value of LA phasic strain on high-risk HF events, and its influencing factors.

STUDY TYPE

Retrospective.

POPULATION

A total of 95 LVNC patients (74 with LA enlargement [LAE] and 21 without LAE) and 50 healthy controls.

FIELD STRENGTH/SEQUENCE

A 3.0 T, balanced steady-state free-precession cine imaging.

ASSESSMENT

LA longitudinal strains were measured by cardiac MRI feature tracking technique. LA volume index (LAVI) and LA ejection fraction (LAEF) were calculated. Their intraobserver and interobserver reproducibility were evaluated. The primary outcome was high-risk HF events, a composite of first HF hospitalization, hospitalization for worsening HF and death from HF.

STATISTICAL TESTS

Student's t/Mann-Whitney U, one-way analysis of variance/Kruskal-Wallis, Chi-squared, receiver operating characteristic, Kaplan-Meier, log-rank, Cox regression, Pearson and Spearman correlation and linear regression analyses were performed. The significance threshold was set at P < 0 .05.

RESULTS

LAEF and LA longitudinal strains decreased in LVNC patients irrespective of the presence of LAE. During a median follow-up of 32.17 months, high-risk HF occurred in 13 (13.68%) patients. Patients with increased LAVI, decreased LAEF and decreased LA longitudinal strain had significantly higher risks of high-risk HF events. In patients with LVNC, LA reservoir strain (εs) was independently associated with high-risk HF (hazard ratio = 23.208 [95% CI: 2.993-179.967]). LV global longitudinal strain (LV GLS) (β = -1.783 [95% CI: -2.493 to -1.073]) was significantly and independently associated with εs. Intraobserver and interobserver reproducibility was excellent for LAVI, LAEF, and LA strain.

CONCLUSION

In patients with LVNC, εs was an independent predictor for high-risk HF events. LV GLS was an independent determinant of εs in LVNC.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 4.

Right ventricle to pulmonary artery coupling after transcatheter aortic valve implantation-Determinant factors and prognostic impact

Introduction

Right ventricular (RV) dysfunction and pulmonary hypertension (PH) have been previously associated with unfavorable outcomes in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI), but little is known about the effect of right ventricle (RV) to pulmonary artery (PA) coupling. Our study aimed to evaluate the determinant factors and the prognostic value of RV-PA coupling in patients undergoing TAVI.

Methods

One hundred sixty consecutive patients with severe AS were prospectively enrolled, between September 2018 and May 2020. They underwent a comprehensive echocardiogram before and 30 days after TAVI, including speckle tracking echocardiography (STE) for myocardial deformation analysis of the left ventricle (LV), left atrium (LA), and RV function. Complete data on myocardial deformation was available in 132 patients (76.6 ± 7.5 years, 52.5% men) who formed the final study population. The ratio of RV free wall longitudinal strain (RV-FWLS) to PA systolic pressure (PASP) was used as an estimate of RV-PA coupling. Patients were analyzed according to baseline RV-FWLS/PASP cut-off point, determined through time-dependent ROC curve analysis, as follows: normal RV-PA coupling group (RV-FWLS/PASP ≥0.63, n = 65) and impaired RV-PA coupling group (RV-FWLS/PASP < 0.63, n = 67).

Results

A significant improvement of RV-PA coupling was observed early after TAVI (0.75 ± 0.3 vs. 0.64 ± 0.3 before TAVI, p < 0.001), mainly due to PASP decrease (p < 0.001). LA global longitudinal strain (LA-GLS) is an independent predictor of RV-PA coupling impairment before and after TAVI (OR = 0.837, p < 0.001, OR = 0.848, p < 0.001, respectively), while RV diameter is an independent predictor of persistent RV-PA coupling impairment after TAVI (OR = 1.174, p = 0.002). Impaired RV-PA coupling was associated with a worse survival rate (66.3% vs. 94.9%, p-value < 0.001) and emerged as an independent predictor of mortality (HR = 5.97, CI = 1.44-24.8, p = 0.014) and of the composite endpoint of death and rehospitalization (HR = 4.14, CI = 1.37-12.5, p = 0.012).

Conclusion

Our results confirm that relief of aortic valve obstruction has beneficial effects on the baseline RV-PA coupling, and they occur early after TAVI. Despite significant improvement in LV, LA, and RV function after TAVI, RV-PA coupling remains impaired in some patients, it is mainly related to persistent pulmonary hypertension and is associated with adverse outcomes.

Usefulness of the pulmonary venous flow waveform for assessing left atrial stiffness

PURPOSE

This study investigated the novel non-invasive left atrial (LA) stiffness parameter using pulmonary venous (PV) flow measurements and the clinical usefulness of the novel LA stiffness parameter.

METHODS

We retrospectively analyzed 237 patients who underwent right heart catheterization and echocardiography less than one week apart. From the pulmonary artery wedge pressure waveform, the difference between x-descent and v-wave (ΔP) was measured. Using the echocardiographic biplane method of disks, the difference between LA maximum volume and that just before atrial contraction (ΔV_MOD) was calculated, and the ΔP/ΔV_MOD was calculated as a standard LA stiffness index. From the PV flow waveform, the peak systolic velocity (S), peak diastolic velocity (D), and minimum velocity between them (R) were measured, and S/D, S/R, and D/R were calculated. From the speckle tracking echocardiography-derived time-LA volume curve, the difference between LA maximum volume and that just before atrial contraction (ΔV_STE) was measured. Each patient's prognosis was investigated until three years after echocardiography.

RESULTS

Among the PV flow parameters, D/R was significantly correlated with ΔP (r = 0.62), and the correlation coefficient exceeded that between S/D and ΔP (r =  - 0.39) or S/R and ΔP (r = 0.14). The [D/R]/ΔV_STE was significantly correlated with ΔP/ΔV_MOD (r = 0.61). During the follow-up, 37 (17%) composite endpoints occurred. Kaplan-Meier analysis showed that patients with [D/R]/ΔV_STE greater than 0.13 /mL were at higher risk of cardiac events.

CONCLUSION

The [D/R]/ΔV_STE was useful for assessing LA stiffness non-invasively and might be valuable in the prognostic evaluation of patients with cardiac diseases.

Prognostic Value of Left Atrial Strain in Aortic Stenosis: A Competing Risk Analysis

BACKGROUND

The role of left atrial (LA) strain as an imaging biomarker in aortic stenosis is not well established. The aim of this study was to investigate the prognostic performance of phasic LA strain in relation to clinical and echocardiographic variables and N-terminal pro-B-type natriuretic peptide in asymptomatic and minimally symptomatic patients with moderate to severe aortic stenosis and left ventricular ejection fraction > 50%.

METHODS

LA reservoir strain (LASr), LA conduit strain (LAScd), and LA contractile strain (LASct) were measured using speckle-tracking echocardiography. The primary outcome was a composite of all-cause mortality, heart failure hospitalization, progression to New York Heart Association functional class III or IV, acute coronary syndrome, or syncope. Secondary outcomes 1 and 2 comprised the same end points but excluded acute coronary syndrome and additionally syncope, respectively. The prognostic performance of phasic LA strain cutoffs was evaluated in competing risk analyses, aortic valve replacement being the competing risk.

RESULTS

Among 173 patients (mean age, 69 ± 11 years; mean peak transaortic velocity, 4.0 ± 0.8 m/sec), median LASr, LAScd, and LASct were 27% (interquartile range [IQR], 22%-32%), 12% (IQR, 8%-15%), and 16% (IQR, 13%-18%), respectively. Over a median of 2.7 years (IQR, 1.4-4.6 years), the primary outcome and secondary outcomes 1 and 2 occurred in 66 (38%), 62 (36%), and 59 (34%) patients, respectively. LASr < 20%, LAScd < 6%, and LASct < 12% were identified as optimal cutoffs of the primary outcome. In competing risk analyses, progressing from echocardiographic to echocardiographic-clinical and combined models incorporating N-terminal pro-B-type natriuretic peptide, LA strain parameters outperformed other key echocardiographic variables and significantly predicted clinical outcomes. LASr < 20% was associated with the primary outcome and secondary outcome 1, LAScd < 6% with all clinical outcomes, and LASct < 12% with secondary outcome 2. LAScd < 6% had the highest specificity (95%) and positive predictive value (82%) for the primary outcome, and competing risk models incorporating LAScd < 6% had the best discriminative value.

CONCLUSIONS

In well-compensated patients with moderate to severe aortic stenosis and preserved left ventricular ejection fractions, LA strain was superior to other echocardiographic indices and incremental to N-terminal pro-B-type natriuretic peptide for risk stratification. LAScd < 6%, LASr < 20%, and LASct < 12% identified patients at higher risk for adverse outcomes.

Left Atrial Remodeling in Response to Aortic Valve Replacement: Pathophysiology and Myocardial Strain Analysis

Severe aortic stenosis (AS) is the most common valve disease in the elderly and is associated with poor prognosis if treated only medically. AS causes chronic pressure overload, concentric left ventricular (LV) hypertrophy, myocardial stiffness, and diastolic dysfunction. This adverse remodeling also affects the left atrium (LA), which dilates and develops myocardial fibrosis, with a reduction in intrinsic function and a consequent high risk of the development of atrial fibrillation. Speckle-tracking echocardiography is able to detect myocardial dysfunction before other conventional parameters, such as LV ejection fraction, and also predict clinical outcomes. This review aims at describing LV and LA remodeling in AS and before and after aortic valve replacement and the usefulness of myocardial strain analysis in this clinical setting.

Preprocedural Multimodality Imaging in Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia worldwide and is associated with increased risk of heart failure, stroke, and death. In current medical practice, multimodality imaging is routinely used in the management of AF. Twenty-one years ago, the ACUTE trial (Assessment of Cardioversion Using Transesophageal Echocardiography) results were published, and the management of AF changed forever by incorporating transesophageal echocardiography guided cardioversion of patients in AF for the first time. Current applications of multimodality imaging in AF in 2022 include the use of transesophageal echocardiography and computed tomography before cardioversion to exclude left atrial thrombus and in left atrial appendage occlusion device implantation. Transesophageal echocardiography, cardiac computed tomography, and cardiac magnetic resonance are clinically used for AF ablation planning. The decision to use a particular imaging modality in AF is based on patient's characteristics, guideline recommendation, institutional preferences, expertise, and cost. In this first of 2-part review series, we discuss the preprocedural role of echocardiography, computed tomography, and cardiac magnetic resonance in the AF, with regard to their clinical applications, relevant outcomes data and unmet needs, and highlights future directions in this rapidly evolving field.

Difference in left atrial myocardial dynamics during reservoir phase between hypertrophic cardiomyopathy and hypertensive heart determined using three-dimensional speckle tracking echocardiography

We aimed to investigate left atrial (LA) myocardial dynamics during reservoir phase using three-dimensional speckle-tracking echocardiography (3DSTE) focusing on its longitudinal-circumferential relationship in patients with left ventricular (LV) hypertrophy and clarifying the difference in LA myocardial reservoir dynamics between hypertrophic cardiomyopathy (HCM) and hypertension with LV hypertrophy (HT-LVH). We studied 4 age-matched groups consisting of 27 patients with HCM, 16 with HT-LVH, 22 hypertensive patients without LV hypertrophy (HT), and 18 normal controls. Using 3DSTE, we measured LA global longitudinal strain (LA-LSR), global circumferential strain (LA-CSR), and global area strain (LA-ASR) during the reservoir phase, as well as LV global longitudinal strain (LV-LS), global circumferential strain (LV-CS), and global area strain (LV-AS). LA-LSR was significantly lower in the HCM and HT-LVH groups than in the controls, but there was no significant difference between the HCM and HT-LVH groups. LA-CSR and LA-ASR were significantly lower in the HCM group than in the other three groups, among which no significant difference was detected. In all subjects, LA-LSR was significantly correlated with LV-LS but not with LV-CS. LA-CSR was correlated with neither LV-LS nor LV-CS. In conclusion, both longitudinal and circumferential LA myocardial expansion during reservoir phase were reduced in HCM, while only the longitudinal one was reduced in HT-LVH. Reduction of LA circumferential expansion may reflect a more serious and intrinsic impairment of LA myocardial distensibility in HCM. Measuring LA-CSR and LA-ASR using 3DSTE would contribute to a more accurate understanding of LA reservoir function abnormality in HCM.

The predictive value of fast semi-automated left atrial long-axis strain analysis for atrial fibrillation in hypertrophic cardiomyopathy

OBJECTIVES

Hypertrophic cardiomyopathy (HCM) patients are closely related to LA functional impairment. Left atrial (LA) strain provides more insight into LA function. The study aimed to investigate the left atrial dysfunction of HCM patients by rapid semi-automatic method and determine the predictive value of left atrial long-axis strain (LAS) for atrial fibrillation (AF).

METHODS

We enrolled 372 HCM patients and 100 healthy participants to assess the LA functional parameters. LAS was obtained by semi-automated tracking of the distance between the mid-posterior point of LA wall which is defined as the intersection of the LA long axis and the posterior wall, and the origins of the mitral valve. The inferior and anterior mitral valve annular insertion points on the 2-chamber view and the lateral and septal insertion points on the 4-chamber view were chosen as the origins of the mitral valve. The clinical outcome was defined as detecting the onset of AF.

RESULTS

The LA strain values were analyzed as 20.8 ± 7.48% for ε_s, 9.81 ± 5.09% for ε_e, and 10.91 ± 4.24% for ε_a in HCM patients, which decreased significantly compared with normal controls. Significant correlations were detected between LV functional parameters and LA strain. During a median follow-up of 61 months, 44 (11.8%) patients developed AF. In the Cox regression analysis, LA strain was identified as a significant predictor of the onset of AF.

CONCLUSIONS

HCM patients had impairment of LA strain before LA enlargement and reduced EF. LA-LAS can be used as a predictive value for predicting the occurrence of AF in HCM patients.

KEY POINTS

• Fast semi-automated long-axis strain analysis by CMR is feasible and effective for evaluating the LA longitudinal function. • Hypertrophic cardiomyopathy patients show significant impairment of left atrial strain before LA enlargement. • The left atrial long-axis strain was an independent predictor of atrial fibrillation in hypertrophic cardiomyopathy.

Prognostic value of left atrial strain in patients with congenital aortic stenosis

Aim

To explore whether left atrial (LA) strain with speckle tracking echocardiography (STE) can contribute to prognostication in patients with congenital aortic stenosis (CAS).

Methods and results

In this prospective study, consecutive outpatients with stable CAS and healthy adults were enrolled between 2011 and 2015. Left atrial function was analysed with STE using Tomtec software. Associations between LA strain (LAS) measurements and primary composite outcome (any adverse cardiovascular event, hospitalization, or re-intervention) and secondary outcome (re-interventions) were assessed with Cox regression analysis. In total, 98 patients with CAS (mean age: 35.0 ± 11.9 year, female: 59.2%) and 121 controls (age: 43.9 ± 13.8 year, female: 55.4%) were included. The majority of patients were in NYHA class I: 97 (99%) at baseline. At baseline, LA conduit strain (LAS-cd) and strain rate (LASR-cd) were significantly lower in patients than in controls when corrected for age and sex (−18.1 ± 8.7 vs. −23.5 ± 9.9%, P = 0.001 and −0.73 ± 0.31 vs. −1.02 ± 0.43/s, P < 0.001). During a median follow-up of 6.4 years (5.7–7.1), the primary composite outcome occurred in 48 (39.6%) patients. Kaplan–Meier analysis showed that decreased LAS-cd (<21%) was associated with a higher occurrence of the primary outcome (log-rank: P = 0.008). Depressed LAS-cd and LASR-cd were both associated with the primary composite outcome [univariable hazard ratio (HR) = 0.64(0.46–0.88), P = 0.005 and HR = 0.68(0.55–0.83), P < 0.001, respectively]; adjusted HR (for LAS-cd and LASR-cd, respectively): 0.31(0.09–1.04), P = 0.06 and 0.49(0.26–0.89), P = 0.02.

Conclusion

Impairment in LA conduit function assessed with STE carries prognostic value in patients with CAS and can be implemented in clinical management.

Prognostic value of diastolic function parameters in significant aortic regurgitation: the role of the left atrial strain

BACKGROUND

The management of patients with asymptomatic significant aortic regurgitation (sAR) is often challenging and appropriate timing of aortic valve surgery remains controversial. Prognostic value of diastolic parameters has been demonstrated in several cardiac diseases. The aim of this study was to analyze the prognostic significance of the diastolic function evaluated by echocardiography, in asymptomatic patients with sAR.

METHODS

A total of 126 patients with asymptomatic sAR evaluated in the Heart Valve Clinic were retrospective included. Conventional echocardiographic systolic and diastolic function parameters were assessed. Left atrial (LA) auto-strain analysis was performed in a sub-group of 57 patients. A combined end-point of hospital admission due to heart failure, cardiovascular mortality, or aortic valve surgery was defined.

RESULTS

During a median follow-up of 34.1 (interquartile range 16.5-48.1) months, 25 (19.8%) patients reached the combined end-point. Univariate analysis showed that LV volumes, LV ejection fraction (LVEF), LV-GLS, E wave, E/e' ratio, LA volume and LA reservoir strain (LASr) were significant predictors of events. Multivariate analysis that tested all classical echocardiographic variables statistically significant in the univariate model showed that LVEDV (HR = 1.02; 95% CI 1.01-1.03; p < 0.001) and E/e' ratio (HR = 1.12; 95% CI 1.03-123; p = 0.01) were significant predictors of events. Kaplan-Meier curve, stratified by median value of LASr, showed that lower LASr values (less than median of 34%) were associated with higher rates of events (p = 0.013).

CONCLUSION

In this population of asymptomatic patients with sAR and normal LV systolic function, baseline diastolic parameters were prognostic markers of cardiovascular events; among them, LASr played a significant predictor role.

The Added Value of Atrial Strain Assessment in Clinical Practice

Speckle tracking echocardiography has emerged as a sensitive tool to analyze myocardial function with improved diagnostic accuracy and prognostic value. Left atrial strain assessment has become a novel imaging method in cardiology with superior prognostic value compared to conventional left atrial volume indices. Left atrial function is divided into three phases, reservoir function being the most important. This review summarizes the added value of speckle tracking echocardiography derived left atrial strain assessment in clinical practice. Recently published data suggest the prognostic value of left atrial reservoir function in heart failure, atrial fibrillation, stroke and valvular heart disease. Furthermore, left atrial reservoir strain proved to be a predictor of cardiovascular morbidity and mortality in the general population. Thus, routine assessment of left atrial function can be an optimal strategy to improve cardiovascular risk prediction and supplement the current risk prediction models.

Evaluation of left atrial dysfunction by speckle tracking echocardiography in systolic and diastolic heart failure

The study aimed to assess the accuracy of two-dimensional speckle tracking echocardiography (2DSTE) to evaluate the left atrial (LA) function in patients with heart failure. And can it differentiate accurately between heart failure preserved ejection fraction (HFpEF, HF with mid-range ejection fraction (HFmrEF=EF 41-49%) and heart failure with reduced ejection fraction (HFrEF= EF<40%)? It included 186 patients of heart failure who were classified into 74 patients with HFpEF (LVEF>50%), 56 patients with HFmrEF (LVEF 41-49%), 56 patients with HFrEF (LVEF<40%), and 50 normal matched subjects. B-type natriuretic peptide (BNP) was more than 35 pg/mL for all patients. The conventional echocardiography evaluated left ventricle systolic and diastolic functions. The 2DSTE evaluated the LV global strain (LVGS), and strain and strain rate (SR) in each phase of LA function. LVGS was -19.3±2.3%, -18.0±1.7%, -16.1±2.0%, and -14.3±2.2 in controls, HFpEF, and HFmrEF, and HFrEF, respectively (p<0.0001); GPALS was 34.1±6.7%, 27.5±4.7%, 21.7±4.8% and 16.9±4.9% in controls, HFpEF, HFmrEF, HFrEF, respectively (p<0.0001); The GPACS was 14.8±4.3%, 12.3±2.2%, 9.7±2.3%, and 7.5±2.6%  in controls, HFpEF, HFmrEF, and HFrEF, respectively (p<0.0001); The PALS-PACS was 19.4±3%, 15.1±4.4%, 12.0±3.4%, and  9.3±3.3% in controls, HFpEF, HFmrEF, and HFrEF (p<0.0001). Therefore, early LA dysfunction in heart failure can be detected accurately and easily by speckle tracking technique that could be a promising independent tool to better understand of heart failure and its classification.

Cardiac Imaging for the Assessment of Left Atrial Mechanics Across Heart Failure Stages

The left atrium (LA) is emerging as a key element in the pathophysiology of several cardiac diseases due to having an active role in contrasting heart failure (HF) progression. Its morphological and functional remodeling occurs progressively according to pressure or volume overload generated by the underlying disease, and its ability of adaptation contributes to avoid pulmonary circulation congestion and to postpone HF symptoms. Moreover, early signs of LA dysfunction can anticipate and predict the clinical course of HF diseases before the symptom onset which, particularly, also applies to patients with increased risk of HF with still normal cardiac structure (stage A HF). The study of LA mechanics (chamber morphology and function) is moving from a research interest to a clinical application thanks to a great clinical, prognostic, and pathophysiological significance. This process is promoted by the technological progress of cardiac imaging which increases the availability of easy-to-use tools for clinicians and HF specialists. Two-dimensional (2D) speckle tracking echocardiography and feature tracking cardiac magnetic resonance are becoming essential for daily practice. In this context, a deep understanding of LA mechanics, its prognostic significance, and the available approaches are essential to improve clinical practice. The present review will focus on LA mechanics, discussing atrial physiology and pathophysiology of main cardiac diseases across the HF stages with specific attention to the prognostic significance. Imaging techniques for LA mechanics assessment will be discussed with an overlook on the dynamic (under stress) evaluation of the chamber.

Left Atrial Strain Determinants During the Cardiac Phases

OBJECTIVES

The present study investigated the determinants of left atrial (LA) strain in all phases of the cardiac cycle.

BACKGROUND

LA strain by speckle-tracking echocardiography allows the assessment of LA function in each phase of the cardiac cycle. However, its determinants and its relation with left ventricular (LV) function have not yet been fully described.

METHODS

The authors performed a retrospective analysis in 127 patients with different cardiovascular pathologies. Using 2-dimensional speckle tracking in 4- and 2-chamber apical views we derived both LA and LV strain curves. Strain-strain loops were reconstructed using LV strain and the corresponding, synchronized LA strain data. Linear regressions were calculated for the entire strain-strain loop as well as for the 3 phases of the cardiac cycle (systole, and early and late diastole). The association between LA strain parameters and LV systolic and diastolic parameters was studied. The prediction of cardiovascular events was evaluated for both measured and predicted LA strain and other parameters.

RESULTS

LA and LV strain curves presented excellent correlations with an R² >0.9 for the cardiac cycle, and >0.97 for its phases. Moreover, the ratios of LV/LA maximal volumes and the slopes of the LA-LV strain-strain loops of the individual patients correlated well (R² = 0.75). In each phase of the cardiac cycle, LA strain parameters correlated well with the corresponding LV strain and the LV-LA volume ratio (R² >0.78). No significant difference in predictive ability of cardiovascular events or atrial fibrillation between the measured and predicted LA strain was observed (P > 0.05 for both).

CONCLUSIONS

In the absence of abnormal LA/LV volume exchange, LA strain is, to a large extent, determined by LV strain and further modulated by the ratio of LV and LA volumes. Nonetheless, measuring LA strain is of high clinical interest because it integrates several parameters into a single, robust, and reproducible measurement.

Imaging of the left atrium: pathophysiology insights and clinical utility

Left atrial imaging and detailed knowledge of its pathophysiology, especially in the context of heart failure, have become an increasingly important clinical and research focus. This development has been accelerated by the growth of non-invasive imaging modalities, advanced image processing techniques, such as strain imaging, and the parallel emergence of catheter-based left atrial interventions like pulmonary vein ablation, left atrial appendage occlusion, and others. In this review, we focus on novel imaging methods for the left atrium, their pathophysiological background, and their clinical relevance for various cardiac conditions and diseases.

The Central Role of Left Atrium in Heart Failure

In past cardiovascular medicine, the attention to the left ventricle-identified as the only indicator and determinant of healthy or unhealthy cardiac conditions- has systematically hidden the role of the left atrium (LA). The recent advances in cardiovascular imaging have provided a better understanding of LA anatomy, physiology, and pathology, making us realize that this functional structure is far from being an innocent spectator. We now know that the LA's mechanical and neuro-hormonal properties play a relevant part in several cardiovascular diseases, including atrial fibrillation, ischemic heart disease, valvular heart disease, and heart failure. The present review aims to describe the role of LA in the specific setting of heart failure. We provide currently available information on LA structure and function and summarize its role as a determinant of symptoms, prognosis, and potential therapeutic target in heart failure patients.

Comparison of left atrial strain measured by feature tracking computed tomography and speckle tracking echocardiography in patients with aortic stenosis

AIMS

Peak left atrial longitudinal strain (PALS) is a marker of the left atrial (LA) reservoir function. Novel feature tracking (FT) software allows assessment of LA strain from multidetector computed tomography (MDCT) data. This study aimed at evaluating the agreement between speckle tracking echocardiography (STE) and FT MDCT for the measurement of PALS in patients with sinus rhythm (SR) and with atrial fibrillation (AF).

METHODS AND RESULTS

The current study included 318 patients (80 ± 7 years, 54% male) with dynamic MDCT data acquired prior to transcatheter aortic valve implantation. PALS was measured by transthoracic echocardiography using STE (PALSecho) and MDCT using dedicated FT software (PALSCT). In the overall population, the median values of PALSecho and PALSCT were 19.0 [interquartile range (IQR) 12.0-25.0] % and 15.3 (IQR 9.2-19.7) %, respectively. High correlation between PALSecho and PALSCT was observed (r = 0.789, P < 0.001) with a mean bias of -3.7%. The correlation between PALSecho and PALSCT was better among patients with SR (N = 258; r = 0.704, P < 0.001) as compared to patients with AF (N = 60; r = 0.622, P < 0.001).

CONCLUSION

PALSecho and PALSCT showed a good agreement in patients with severe aortic stenosis (AS) regardless of the cardiac rhythm. FT MDCT may be an important adjuvant modality for assessing LA reservoir function in patients with severe AS.

Left atrial strain is a predictor of left ventricular systolic and diastolic reverse remodelling in CRT candidates

AIMS

The left atrium (LA) has a pivotal role in cardiac performance and LA deformation is a well-known prognostic predictor in several clinical conditions including heart failure with reduced ejection fraction. The aim of this study is to investigate the effect of cardiac resynchronization therapy (CRT) on both LA morphology and function and to assess the impact of LA reservoir strain (LARS) on left ventricular (LV) systolic and diastolic remodelling after CRT.

METHODS AND RESULTS

Two hundred and twenty-one CRT-candidates were prospectively included in the study in four tertiary centres and underwent echocardiography before CRT-implantation and at 6-month follow-up (FU). CRT-response was defined by a 15% reduction in LV end-systolic volume. LV systolic and diastolic remodelling were defined as the percent reduction in LV end-systolic and end-diastolic volume at FU. Indexed LA volume (LAVI) and LV-global longitudinal (GLS) strain were the main parameters correlated with LARS, with LV-GLS being the strongest determinant of LARS (r = -0.59, P < 0.0001). CRT induced a significant improvement in LAVI and LARS in responders (both P < 0.0001). LARS was an independent predictor of both LV systolic and diastolic remodelling at follow-up (r = -0.14, P = 0.049 and r = -0.17, P = 0.002, respectively).

CONCLUSION

CRT induces a significant improvement in LAVI and LARS in responders. In CRT candidates, the evaluation of LARS before CRT delivery is an independent predictor of LV systolic and diastolic remodelling at FU.

Diagnosis and Management of Aortic Valve Stenosis: The Role of Non-Invasive Imaging

Aortic stenosis is the most common heart valve disease necessitating surgical or percutaneous intervention. Imaging has a central role for the initial diagnostic work-up, the follow-up and the selection of the optimal timing and type of intervention. Referral for aortic valve replacement is currently driven by the severity and by the presence of aortic stenosis-related symptoms or signs of left ventricular systolic dysfunction. This review aims to provide an update of the imaging techniques and seeks to highlight a practical approach to help clinical decision making.

Prognostic power of left atrial strain in patients with acute heart failure

AIMS

Left atrial (LA) dysfunction can be associated with left ventricular (LV) disorders; however, its clinical significance has not been well-studied in patients with acute heart failure (AHF). We evaluated prognostic power of peak atrial longitudinal strain (PALS) of the left atrium according to heart failure (HF) phenotypes and atrial fibrillation (AF).

METHODS AND RESULTS

From an AHF registry with 4312 patients, we analysed PALS in 3818 patients. Patients were categorized into PALS tertiles. We also divided the patients according to HF phenotypes [HF with reduced ejection fraction (HFrEF), HF with mid-range ejection fraction (HFmrEF), or HF with preserved ejection fraction (HFpEF)] and presence of AF. The primary outcomes were all-cause mortality and HF hospitalization. PALS was weakly but significantly correlated with LA volume index (r = -0.310, P < 0.001), E/e' (r = -0.245, P < 0.001), and LV ejection fraction (r = 0.371, P < 0.001). A total of 2016 patients (52.8%) experienced adverse clinical events during median follow-up duration of 30.6 months (interquartile ranges 11.6-54.4 months). In the multivariate analysis, PALS was a significant predictor of events [hazard ratio (HR) 0.984, 95% confidence interval (CI) 0.971-0.996; P = 0.012]. Patients with the lowest tertile (HR 1.576, 95% CI 1.219-2.038; P < 0.001) had a higher number of events than those with the highest tertile in the multivariate analysis. In the subgroup analysis, however, PALS was not a prognosticator (HR 0.987, 95% CI 0.974-1.000; P = 0.056) in AF patients. The prognostic power of PALS was not different between HFrEF (HR 0.977, 95% CI 0.969-0.974; P < 0.001), HFmrEF (HR 0.984, 95% CI 0.972-0.996; P = 0.008), and HFpEF (HR 0.980, 95% CI 0.973-0.987; P < 0.001, P for interaction = 0.433).

CONCLUSION

PALS was a significant prognostic marker in AHF patients. The prognostic power was similar regardless of HF phenotypes, but PALS was not associated with clinical events in AF patients.

Early reduction of left atrial function predicts adverse clinical outcomes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

Aims

To investigate the changes in left atrial strain (LAS) after correction of severe aortic stenosis (AS) with transcatheter aortic valve replacement (TAVR) and assess its prognostic impact.

Methods and results

One hundred consecutive patients with severe symptomatic AS who underwent TAVR at the Magna Graecia University of Catanzaro underwent echocardiographic examination including assessment of LAS before and after TAVR. Independent investigators collected outcome data and information. The primary study outcome was the difference in ΔLAS (postTAVR–preTAVR) between patients those met the main clinical endpoint (a composite of cardiovascular mortality and heart failure hospitalisation) and those not meeting the endpoint.

During a median follow-up of 31 months, 35 patients (35%) met the combined clinical endpoint. The difference between LAS post-TAVR and LAS pre-TAVR (ΔLAS) was significantly larger in patients who met the combined endpoint (HR=0.76 (0.67–0.86); p<0.001). Multivariate logistic regression analysis including ΔLAS, EuroSCORE II and left ventricular ejection fraction showed that ΔLAS (HR=0.80, p<0.001) was the only independent predictor of the combined clinical endpoint. Finally, a Kaplan-Maier analysis showed that patients with a ΔLAS above its median value had a significantly better event-free survival compared with those below the median (p<0.001).

Conclusions

A lower reduction in ΔLAS after TAVR was an independent predictor of the primary composite outcome of cardiovascular death and hospitalisation for heart failure.

Left Atrial Strain Associated with Functional Recovery in Patients Receiving Optimal Treatment for Heart Failure

BACKGROUND

Heart failure with recovered ejection fraction (HFrecEF) has been reported in several previous studies to have a better prognosis than heart failure with reduced ejection fraction (HFrEF). However, the factors associated with HFrecEF have not been identified. The aim of this study was to test the hypothesis that left atrial (LA) strain could help identify patients with recovered ejection fraction (EF) among those with heart failure (HF) with low EF on admission.

METHODS

One hundred consecutive patients hospitalized for the first time for new-onset HF were enrolled. Patients were clinically diagnosed with HFrEF on admission (left ventricular EF < 40%) and received optimal treatment for HF. Twenty-eight patients improved to HFrecEF during 6 months of follow-up.

RESULTS

Regarding clinical background, there were significantly more women and a lower rate of atrial fibrillation in the HFrecEF group than in the HFrEF group. In a multivariate logistic regression analysis, LA strain was an independent predictor of HFrecEF, even after adjustment for gender and left ventricular EF (odds ratio: 4.06; 95% CI: 2.04-8.07; P < .001). A cutoff value of 10.8% for LA strain showed high sensitivity (96%) and specificity (82%) in identifying HFrecEF in patients with HF presenting with low EF on admission. During a follow-up period of 24 ± 13 months, 31 patients (31%) had cardiovascular death or readmission for HF. Patients with reduced LA strain (<10.8%) had significantly shorter event-free survival than those with preserved LA strain (P = .02).

CONCLUSIONS

LA strain is a useful indicator for predicting HFrecEF and should be considered as a routine measurement in patients with HFrEF on admission.

The Prognostic Value of Left Atrial Global Longitudinal Strain and Left Atrial Phasic Volumes in Patients Undergoing Transcatheter Valve Implantation for Severe Aortic Stenosis

INTRODUCTION

The changes and the prognostic implications of left atrial (LA) volumes (LAV), LA function, and vascular load in patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS) are less known.

METHODS

We enrolled 150 symptomatic patients (mean age 82 ± 8 years, 58% female, and pre-TAVI aortic valve area 0.40 ± 0.19 cm/m2) with severe AS who underwent 2D transthoracic echocardiography and 2D speckle tracking echocardiography at average 21 ± 35 days before and 171 ± 217 days after TAVI. The end point was a composite of new onset of atrial fibrillation, hospitalization for heart failure and all-cause death (major adverse cardiac events [MACE]).

RESULTS

After TAVI, indexed maximal LA volume and minimum volume of the LA decreased by 2.1 ± 10 mL/m2 and 1.6 ± 7 mL/m2 (p = 0.032 and p = 0.011, respectively), LA function index increased by 6.8 ± 11 units (p < 0.001), and LA stiffness decreased by 0.38 ± 2.0 (p = 0.05). No other changes in the LA phasic volumes, emptying fractions, and vascular load were noted. Post-TAVI, both left atrial and ventricular global peak longitudinal strain improved by about 6% (p = 0.01 and 0.02, respectively). MACE was reached by 37 (25%) patients after a median follow-up period of 172 days (interquartile range, 20-727). In multivariable models, MACE was associated with both pre- and post-TAVI LA global peak longitudinal strain (hazard ratio [HR] 0.75, CI 0.59-0.97; and HR 0.77, CI 0.60-1.00, per 5 percentage point units, respectively), pre-TAVI LV global endocardial longitudinal strain (HR 1.37, CI 1.02-1.83 per 5 percentage point units), and with most of the LA phasic volumes.

CONCLUSION

Within 6 months after TAVI, there is reverse LA remodeling and an improvement in LA reservoir function. Pre- and post-TAVI indices of LA function and volume remain independently associated with MACE. Larger studies enrolling a greater diversity of patients may provide sufficient evidence for the utilization of these imaging biomarkers in clinical practice.

Modeling of aortic valve stenosis using fluid-structure interaction method

BACKGROUND AND OBJECTIVES

Fluid structure interaction (FSI) is defined as interaction of the structures with contacting fluids. The aortic valve experiences the interaction with blood flow in systolic phase. In this study, we have tried to predict the hemodynamics of blood flow through a normal and stenotic aortic valve in two relaxation and exercise conditions using a three-dimensional FSI method.

METHODS

The aorta valve was modeled as a three-dimensional geometry including a normal model and two others with 25% and 50% stenosis. The geometry of the aortic valve was extracted from CT images and the models were generated by MMIMCS software and then they were implemented in ANSYS software. The pulsatile flow rate was used for all cases and the numerical simulations were conducted based on a time-dependent domain.

RESULTS

The obtained results including the velocity, pressure, and shear stress contours in different systolic time sequences were explained and discussed. The maximum blood flow velocity in relaxation phase was obtained 1.62 m/s (normal valve), 3.78 m/s (25% stenosed valve), and 4.73 m/s (50% stenosed valve). In exercise condition, the maximum velocities are 2.86, 4.32, and 5.42 m/s respectively. The maximum blood pressure in relaxation phase was calculated 111.45 mmHg (normal), 148.66 mmHg (25% stenosed), and 164.21 mmHg (50% stenosed). However, the calculated values in exercise situation were 129.57, 163.58, and 191.26 mmHg.The validation of the predicted results was also conducted using existing literature.

CONCLUSIONS

We believe that such model are useful tools for biomechanical experts. The further studies should be done using experimental data and the data are implemented on the boundary conditions for better comparison of the results.

Incremental prognostic role of left atrial reservoir strain in asymptomatic patients with moderate aortic stenosis

Left atrial (LA) mechanics assessed by two-dimensional speckle tracking echocardiography (2D-STE) have not been extensively studied and clearly characterized in patients with moderate aortic stenosis (AS). Accordingly, we aimed to evaluate the usefulness of LA reservoir strain for risk stratification of asymptomatic patients with moderate AS. This retrospective study included all consecutive asymptomatic patients with moderate AS who underwent transthoracic echocardiography implemented with 2D-STE analysis of LA myocardial strain and strain rate indices at our Institution, between February 2011 and September 2019. During the follow-up period, we evaluated the occurrence of any of the following: (1) CV hospitalization; (2) The recourse to AS surgery; (3) Cardiac death or sudden death. A total of 186 patients (mean age 71.9 ± 12.7 years, 61.8% men) were included in the present study. During a mean follow-up of 2.3 ± 1.9 years, no patients died and 63 adverse CV events were recorded: 48 patients were hospitalized because of heart failure (28 patients), acute coronary syndrome (10 patients), arrhythmias (10 patients) and 15 patients underwent AS surgery. At the multivariate Cox regression analysis, type 2 diabetes mellitus (OR 1.87, 95%CI 1.05-3.34, p = 0.03), NT-proBNP (OR average 1.14, 95%CI 1.02-1.27, p = 0.02), average E/e' ratio (OR 1.07, 95%CI 1.01-1.15, p = 0.04) and most of all left atrial positive global strain (LA-GSA+) (OR 0.85, 95%CI 0.81-0.90, p < 0.0001) were independently associated with the outcome. LA-GSA+ (optimal cut-off ≤ 19%, AUC = 0.94, 87% sensitivity, 99% specificity, positive predictive value 99%, negative predictive value 88%) showed the highest diagnostic performance. An impaired LA reservoir strain can contribute to identify a subset of asymptomatic patients with moderate AS at higher risk, who may benefit from closer echocardiographic follow-up and/or early surgery.

Left atrial functional assessment and mortality in patients with severe aortic stenosis with sinus rhythm

BACKGROUND

Aortic valve stenosis (AS) is the most common primary valvular heart disease leading to surgical or percutaneous aortic valve replacement (AVR) in Europe and its prevalence keeps growing. While other risk factors in severe AS are well documented, little is known about the prognostic value of left atrial (LA) function in AS. Our aim is to clarify the relationship between LA function measured at severe AS diagnosis (evaluated by means of volumetric assessment) and all-cause mortality during follow-up.

METHODS

We retrospectively evaluated patients diagnosed with severe AS for the first time at our echocardiography laboratory. We evaluated LA reservoir, conduit and pump function by measuring LA volumes at different timings of cardiac cycle. Treatment strategy was decided according to heart team consensus and patient decision. We divided patients into groups according to terciles of LA reservoir, conduit and pump function. Primary outcome was defined by the occurrence of all-cause mortality during follow-up.

RESULTS

A total of 408 patients were included in the analysis, with a median follow-up time of 45 months (interquartile range 54 months). 57.9% of patients underwent AVR and 44.9% of patients registered the primary outcome during follow-up. Left atrial emptying fraction (LAEF) was the best LA functional parameter and the best overall parameter in discriminating primary outcome (AUC 0.845, 95%CI 0.81-0.88, P < 0.001). After adjustment for clinical, demographic and echocardiographic variables, cumulative survival of patients with LAEF < 37% and LAEF 37 to 53% relative to patients with LAEF ≥54% remained significantly lower (HR 13.91, 95%CI 6.20-31.19, P < 0.001 and HR 3.40, 95%CI 1.57-7.37, P = 0.002, respectively). After adjustment for AVR, excess risk of LAEF < 37% and LAEF 37 to 53% relative to LAEF ≥54% remained significant (HR 11.71, 95%CI 5.20-26.40, P < 0.001 and HR 3.59, 95%CI 1.65-7.78, P = 0.001, respectively).

CONCLUSIONS

In patients with a first diagnosis of severe AS, LA function, evaluated by means of volumetric assessment, is an independent predictor of all-cause mortality and a more potent predictor of death compared to classical severity parameters. These data can be useful to identify high-risk patients who might benefit of AVR.

The Prognostic Value of Left Atrial Reservoir Functional Indices Measured by Three-Dimensional Speckle-Tracking Echocardiography for Major Cardiovascular Events

BACKGROUND

Left atrial (LA) volume and left ventricular longitudinal strain (LVLS) have significant prognostic values for major cardiovascular events (MACEs). Prognostic values of LA reservoir functional indices measured by 3-dimensional (3D) speckle-tracking echocardiography (STE) were evaluated.Methods and Results:A total of 264 patients, who underwent 2-dimensional (2D) echocardiography and 3DSTE for various underlying heart diseases, were followed up to record MACE. After a mean follow up of 547±435 days, 30 patients developed MACE: 7 cardiac deaths, 6 strokes, 1 non-fatal myocardial infarction, and 22 admissions for heart failure (5 of these had cardiac death after discharge, whereas 1 sustained stroke after discharge). Receiver operating characteristic curve analysis was performed to determine the optimal cut-off levels of 4 LA functional indices: LA emptying fraction (LAEmpF), LA longitudinal strain (LALS), LA circumferential strain (LACS), and LA area change ratio (LAAC), using 3DSTE. Among these factors, 2DLVLS, 3DLAEmpF, and 3DLALS demonstrated a higher hazard ratio (>5.0) than other variables. The 3DLAEmpF and 3DLALS had a higher average treatment effect (ATE) and ATE on the treated (ATT), respectively, than the other indices after propensity score matching. Addition of 3DLAEmpF to the base model using clinical variables and LV ejection fraction or 2DLVLS demonstrated higher prognostic power.

CONCLUSIONS

LAEmpF calculated using 3DSTE possessed additive prognostic values for the prediction of MACE.

Multicentric Atrial Strain COmparison between Two Different Modalities: MASCOT HIT Study

Two methods are currently available for left atrial (LA) strain measurement by speckle tracking echocardiography, with two different reference timings for starting the analysis: QRS (QRS-LASr) and P wave (P-LASr). The aim of MASCOT HIT study was to define which of the two was more reproducible, more feasible, and less time consuming. In 26 expert centers, LA strain was analyzed by two different echocardiographers (young vs senior) in a blinded fashion. The study population included: healthy subjects, patients with arterial hypertension or aortic stenosis (LA pressure overload, group 2) and patients with mitral regurgitation or heart failure (LA volume–pressure overload, group 3). Difference between the inter-correlation coefficient (ICC) by the two echocardiographers using the two techniques, feasibility and analysis time of both methods were analyzed. A total of 938 subjects were included: 309 controls, 333 patients in group 2, and 296 patients in group 3. The ICC was comparable between QRS-LASr (0.93) and P-LASr (0.90). The young echocardiographers calculated QRS-LASr in 90% of cases, the expert ones in 95%. The feasibility of P-LASr was 85% by young echocardiographers and 88% by senior ones. QRS-LASr young median time was 110 s (interquartile range, IR, 78-149) vs senior 110 s (IR 78-155); for P-LASr, 120 s (IR 80-165) and 120 s (IR 90-161), respectively. LA strain was feasible in the majority of patients with similar reproducibility for both methods. QRS complex guaranteed a slightly higher feasibility and a lower time wasting compared to the use of P wave as the reference.

Left atrial function assessed by speckle tracking echocardiography in anthracycline-induced cardiotoxicity: a case report

Background

The onset prevention and early diagnosis in cardiotoxicity due to cancer chemotherapy are important, and it is important to detect cardiac dysfunction at an early stage and start treatment to enhance the therapeutic effect.

Case summary

A 31-year-old female with breast cancer received chemotherapy with epirubicin (400 mg/m²) and cyclophosphamide followed by docetaxel. Two months after the initiation of her chemotherapy, the left ventricular (LV) ejection fraction (LVEF) determined by echocardiography fell to 41.2%, and she was diagnosed with cancer therapy-related cardiac dysfunction (CTRCD). Three months after the initiation of cancer treatment, the peak velocity of late diastolic transmitral Doppler flow (A wave) became undetectable. Peak longitudinal strain (LS) and peak LS rate, which reflect left atrium (LA) reservoir function, gradually declined like the LVEF and LV-global LS (GLS). Seven months after the initiation of cancer treatment, she was diagnosed with acute decompensated heart failure. The changes in peak LS and peak LS at the onset were greater than those in LVEF and LV-GLS.

Discussion

This is a case report suggesting that LA reservoir function might be a more sensitive indicator than LVEF or LV-GLS in detecting CTRCD and that LA booster function might be the earliest. Left atrium reservoir function might be a more sensitive than conventional LV pump function and optimal indicator in CTRCD.

Left atrial stiffness in women with ischemia and no obstructive coronary artery disease: Novel insight from left atrial feature tracking

BACKGROUND

Women with signs and symptoms of ischemia and no obstructive coronary artery disease (INOCA) are at risk of heart failure with preserved ejection fraction (HFpEF); however, the mechanism for HFpEF progression remains unclear. Studies in INOCA have largely focused on left ventricular function. The left atrium serves an important role in maintaining transmitral flow, and is impaired in HFpEF; however, it remains unclear if left atrial function is impaired in INOCA.

HYPOTHESIS

Left atrial function is progressively worse in INOCA and HFpEF compared to controls.

METHODS

We compared 39 reference control subjects to 64 women with INOCA and 22 subjects with HFpEF. Left atrial strain was assessed by feature tracking using magnetic resonance cine images.

RESULTS

Peak left atrial strain was reduced in HFpEF compared to controls (22.9 ± 4.8% vs 25.9 ± 3.2%, P < .01), but similar in INOCA (24.8 ± 4.5%) compared to HFpEF and controls (P = .18). However, left ventricular end-diastolic pressure (LVEDP) was elevated in 33% of INOCA participants, suggesting that left atrial stiffness (LVEDP/LA strain) is elevated in a large portion of women with INOCA.

CONCLUSIONS

Taken together, we interpret these data to support our working hypothesis that INOCA is a pre-HFpEF state, with left atrial stiffness preceding overt left atrial dysfunction; representing a putative therapeutic target to prevent HFpEF progression in this at-risk population.

Left and right atrial speckle tracking: Comparison of three methods of time reference gating

BACKGROUND

Atrial function has a close interdependence with ventricular function and plays a central role in maintaining optimal cardiac function. There are two well-defined timing methods used to determine the start point. The aim of this prospective study was to objectively assess the influence of gating method selection on reported left and right strain values within the same group of healthy subjects.

METHODS

101 volunteers (44 male, 57 female) had adequate tracking for analysis on TomTec Imaging Systems (Unterschleissheim, Germany). The median age was 41 years (range 19-79 years, interquartile range 30-52 years). Atrial strain by 2D-speckle tracking echocardiography was evaluated using two commonly applied zero baseline time reference methods: R-R gating and P-P gating, in addition to volume gating (defining end-systole at the atrial maximum and end-diastole at the atrial minimum).

RESULTS

True atrial minimum occurred prior to the onset of the QRS in most healthy volunteers. There was a significant difference for LA and RA reservoir strain between volume gating and R-R gating (mean difference, 4.63%; P < .001 for LA; mean difference, 4.23%; P < .001 for RA), as well as volume gating and P-P gating (mean difference, 5.26%; P < .001 for LA; mean difference, 6.24%; P < .001 for RA). Noticeably, reservoir strain was comparable between R-R gating and P-P gating (mean difference, 0.58%, P = .06) in LA, but not on RA (mean difference, 2.02%, P < .001).

CONCLUSIONS

There was variability in atrial strain values depending on the zero baseline time reference method used.

The prognostic role of speckle tracking echocardiography in clinical practice: evidence and reference values from the literature

Speckle tracking echocardiography (STE) is a second-level echocardiographic technique which has gradually gained relevance in the last years. It allows semi-automatic quantification of myocardial deformation and function, overcoming most of the limitations characterizing basic echocardiography and providing an early detection of cardiac impairment. Today, its feasibility and usefulness are highly supported by literature. In particular, several studies demonstrated that STE could provide additional prognostic information beyond conventional echocardiographic and traditional clinical parameters. Moreover, a recent standardization of speckle tracking analysis regarding all cardiac chambers paved the way for the integration of STE in diagnostic and prognostic protocols for particular clinical settings. The aim of this review is to describe the prognostic role of STE in different clinical scenarios basing on currently available evidence.

The left atrial function is transiently impaired in Tako-tsubo cardiomyopathy and associated to in-hospital complications: a prospective study using two-dimensional strain

Tako-tsubo cardiomyopathy (TTC) is characterized by the presence of transient left ventricular (LV) dysfunction. Whether left atrial (LA) function is also impaired in this setting is unclear. To assess prospectively LA peak systolic longitudinal strain (LAS) by two-dimensional strain at the acute phase of TTC and after recovery and its association with in-hospital complications. 40 patients with typical TTC (mean age 79.5 ± 10 years) underwent transthoracic-Doppler echocardiography at the acute phase and at follow-up (32 ± 18 days later), including the measurement of the LAS (mean of maximal strain from the 4-2 chamber views). A control group of 15 patients (75 ± 7 years, 13 women) without overt cardiovascular disease served as a comparative group. In-hospital complication was a composite of death, heart failure, cardiogenic shock, LV thrombus, and sustained ventricular arrhythmia. In the TTC group, LAS improved significantly between the two examinations from 15 ± 5.5% to 27 ± 8% (p < 0.01) whereas LA volume did not change (p = NS). In the control group LAS was 30 ± 4% (p < 0.01 vs. TTC acute phase, p = NS vs. TTC follow-up). In TTC, at the acute phase LAS was independently correlated to LV global longitudinal strain (LVGLS), and after recovery to E/e', and the change of LAS was independently correlated to the change of the LVGLS (all, p < 0.01). Furthermore LAS was independently correlated to in-hospital complications (p < 0.01). LA function (reservoir) is transiently impaired in TTC and associated to in-hospital complications. Furthermore, the improvement of LAS parallel the dynamic improvement of LVGLS suggests that TTC induces a transient global left heart dysfunction.