Prognostic value of left atrioventricular coupling index in patients undergoing transcatheter aortic valve implantation: a prospective echocardiographic study

Introduction

Aortic stenosis (AS) is a progressive obstructive valvular disease that induces pathological remodeling in the left atrium (LA) and left ventricle (LV). Chronically elevated pressure in the LV leads to hypertrophy and fibrosis, ultimately causing LA enlargement and remodeling for maintaining adequate LV filling (1-3). Without timely treatment, the mortality rate among patients with severe symptomatic AS exceeds 50% within 2 years (4). With the accelerated aging of the population, the incidence of AS is rising, and transcatheter aortic valve implantation (TAVI) is being increasingly used in patients with severe symptomatic AS (5,6).

Numerous studies have demonstrated that TAVI effectively improves hemodynamics, survival rates, and quality of life in patients with AS (7). However, TAVI for patients with AS nonetheless involves significant challenges. The marked heterogeneity in clinical presentation, pathophysiological mechanisms, and prognosis across patients complicates surgical risk assessment and prognostic prediction (8). Left ventricular diastolic dysfunction has been identified as an independent predictor of mortality after surgical aortic valve replacement (9), and preoperative LV diastolic dysfunction grading correlates with risk stratification for all-cause mortality following TAVI (10).

Recent studies have established left atrioventricular coupling index (LACI) as a novel diastolic function parameter (11,12). LACI is defined as the ratio of LA end-diastolic volume (LAEDV) to LV end-diastolic volume (LVEDV) (13). LACI correlates with the severity of LV diastolic dysfunction and serves as an independent prognostic marker for outcomes in patients with heart failure (11). It has been validated as a predictor of cardiovascular outcomes across diverse conditions, including acute myocardial infarction, heart failure, hypertrophic cardiomyopathy, Fabry disease, and chronic kidney disease (14-18). In predicting cardiovascular events, LACI is considered superior to traditional risk factors and single-chamber parameters such as E/e' and LA volume (12). The size and function of the LA are intricately linked to LV remodeling and function. During systole, the LA and LV are separated by a closed mitral valve, whereas during diastole, the two chambers directly connect and tightly couple in the absence of mitral stenosis (19). Therefore, left atrioventricular coupling may better reflect integrated LA-LV function and serve as a stronger outcome predictor than may each of the LA or LV parameters alone. Importantly, LACI is derived from conventional echocardiographic measurements, which eliminates the need for postprocessing analysis (unlike atrial and ventricular speckle-tracking parameters) and reduces vendor-specific variability, making it more suitable for clinical implementation.

Despite these advantages, research on the predictive value of echocardiography-based LACI in TAVI populations remains limited, and its prognostic utility has not been thoroughly assessed. This study thus aimed to examine the association between LACI and adverse cardiovascular events in patients after TAVI. We present this article in accordance with the STROBE reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-989/rc).

Methods

Study population

Between June 2021 and December 2024, 177 patients with moderate-to-severe AS underwent TAVI at The First Affiliated Hospital of Guangxi Medical University. AS was diagnosed according to the 2017 guidelines for the echocardiographic assessment of valvular heart disease published jointly by the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE), which integrate multidimensional data including peak gradient, mean gradient, and valve area for stenosis grading. As shown in Figure 1, 8 patients who died in-hospital postoperatively and 21 patients with atrial fibrillation (which substantially impacts LACI) were excluded, leaving 148 patients included in the final analysis of this study.

Figure 1 Study flowchart. AS, aortic stenosis; MACE, major adverse cardiac event; TAVR, transcatheter aortic valve replacement.

Clinical data from patients scheduled for TAVI were collected through the medical record system, including demographic characteristics, cardiovascular risk factors, European System for Cardiac Operative Risk Evaluation (EuroSCORE) II, New York Heart Association (NYHA) functional class, estimated glomerular filtration rate (eGFR), and comorbidities. Echocardiographic data were obtained within 1 week before the procedure when patients were in a clinically stable condition. This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study protocol was approved by The First Affiliated Hospital of Guangxi Medical University ethics committee (approval No. 2025-E0252). All patients provided written informed consent after being fully informed of TAVI-specific risks, alternative treatments, and pre- and postprocedural data collection.

Echocardiography

Preoperative transthoracic echocardiography (TTE) was performed within 1 week before TAVI on hemodynamically stable patients with the Epiq 7C and CVX systems (Philips Healthcare, Amsterdam, the Netherlands) with S5-1 and X5-1 matrix cardiac transducers (frequency 1–5 MHz). Echocardiographic protocols were based on the guidelines from the ASE and EACVI (20,21). In the parasternal long-axis view, measurements of LV end-diastolic diameter (LVEDD) and mean ventricular wall thickness were obtained. Left ventricular ejection fraction (LVEF) and left atrial volume index (LAVI) were calculated via the modified Simpson method. From the apical four-chamber view, peak early diastolic velocity (E), peak late diastolic velocity (A), and mitral annular early diastolic peak velocity (e’) and late diastolic peak velocity (a’) at both the septal and lateral sides were measured. In the apical five-chamber view, forward flow spectrum of the LV outflow tract and transaortic valve flow spectrum were acquired, with the aortic valve area calculated via the continuity equation method. Valvular regurgitation volumes and regurgitant spectra were evaluated across multiple views. Strain data for the LV and LA were obtained via two-dimensional speckle-tracking echocardiography, with LV global longitudinal strain (LVGLS) calculated as the average of 18 myocardial segments. Left atrial strain was measured from the apical four-chamber view, with the zero strain reference point set at end-diastole to derive LA reservoir strain (LASr). LACI was calculated as the ratio of LA minimum volume to LVEDV. To minimize bias, echocardiography assessors were blinded to patients’ clinical histories and data. All measurements were repeated three times and averaged.

LACI

In Figure 2, LACI is defined as the ratio of LAEDV to LVEDV. LA and LV volumes were measured at the same end-diastole defined by mitral valve closure. LACI values are expressed as percentages, with a higher LACI indicating a greater mismatch between LA and LV volumes at ventricular end-diastole and thus more severe impairment of left atrioventricular coupling.

Figure 2 LACI in the different groups. LACI, defined as the ratio of minimum left atrial volume to maximum left ventricular volume at end-diastole, was impaired in the MACE group (A) as compared to non-MACE group (B). LACI, left atrioventricular coupling index; LAEDV, left atrial end-diastolic volume; LVEDV, left ventricular end-diastolic volume; MACE, major adverse cardiac event.

Follow-up and clinical endpoints

Follow-up data were collected via medical record review and telephone follow-up until December 31, 2024. The primary endpoint was major adverse cardiac events (MACEs), defined as a composite of malignant arrhythmia, heart failure rehospitalization, and all-cause mortality during follow-up. Malignant arrhythmias could include either tachyarrhythmias (sustained ventricular tachycardia, ventricular fibrillation, or newly developed atrial fibrillation/flutter with hemodynamic instability) or bradyarrhythmias (newly developed high-degree/third-degree atrioventricular block, symptomatic sinus arrest >3 seconds, or pacemaker-dependent bradycardia) and were considered present if at least one of the following three criteria were met: causing syncope or requiring resuscitation for sudden cardiac arrest, leading to cardiogenic shock, or requiring emergency interventions such as electrical cardioversion/defibrillation or temporary pacing (22). Based on outcomes, patients were divided into MACE and non-MACE groups for comparative analysis and survival modeling.

Statistical analysis

Continuous variables are presented as the mean ± standard deviation. Nonnormally distributed data are expressed as the median and interquartile range. High-sensitivity cardiac troponin T (hs-cTnT) and B-type natriuretic peptide (BNP) levels were logarithmically transformed due to a nonnormal distribution. Categorical variables are reported as frequencies or percentages. The Student’s t-test, Mann-Whitney test, or chi-squared test was used to compare clinical characteristics between the MACE and non-MACE groups. Univariate and multivariate Cox proportional hazards analyses were performed to identify independent predictors of MACE occurrence and to evaluate their prognostic value. Clinically relevant variables with P<0.05 in the univariate Cox models were included in the multivariate analysis. Receiver operating characteristic (ROC) curves were constructed to assess the ability of the LACI to predict MACE occurrence, the area under the curve (AUC) was calculated to determine the optimal cutoff values, and the DeLong test was employed to evaluate differences in discriminatory ability between LACI and other indices. Kaplan-Meier analysis was used to determine the cumulative incidence of adverse events, and the log-rank test was applied to compare left atrioventricular decoupling and coupling index groups based on the cutoff values. All statistical analyses were performed with R software version 4.2.2 (The R Foundation for Statistical Computing, Vienna, Austria) and MSTATA software (https://www.mstata.com/).

Results

Clinical characteristics of patients

As shown in Figure 1, 177 patients with moderate-to-severe AS were enrolled between June 2021 and December 2024. After excluding 8 patients who died in hospital after the procedure and 21 patients with atrial fibrillation were excluded (which substantially impacts LACI), 148 patients (mean age 81.3±4.8 years; 40.5% female; mean EuroSCORE II 2.79%±1.13%) were ultimately included. During a median follow-up of 13 months [interquartile range (IQR), 6–27 months] after TAVI, 25 MACEs occurred. Overall, 5 (3.3%) patients were rehospitalized due to heart failure, 9 (6.1%) were rehospitalized for malignant arrhythmias, and 11 (7.4%) died postoperatively. Based on the follow-up outcomes, patients were divided into MACE and non-MACE groups. Table 1 summarizes the clinical characteristics of the two groups. There were no significant differences between the groups in age, sex, body mass index (BMI), smoking history, prior coronary interventions [e.g., percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG)], history of cerebral infarction or hemorrhage, lipid profiles, or eGFR. However, the MACE group, as compared to the non-MACE group, had significantly higher rates of hypertension, diabetes mellitus, and coronary artery disease (CAD), as well as lower hs-cTnT levels, higher EuroSCORE II scores, and worse NYHA functional class.

Pre-TAVI echocardiography (≤7 days) showed that over 50% of patients in both groups had valvular regurgitation, predominantly mild in severity; among the entire cohort, moderate-or-greater regurgitation of the aorta, mitral valve, and tricuspid valve was observed in 2.1%, 4.8%, and 0.7% of the patients, respectively. No significant differences were observed in LVEDD, severity of valvular regurgitation, or degree of AS between the two groups. However, the MACE group exhibited significantly higher LAVI, E/e' ratio, and tricuspid regurgitation (TR) peak gradient (TRPG), along with worse LVGLS (11.30±2.76 vs. 13.28±2.28; P<0.001) and LACI (37.84±10.38 vs. 28.18±6.05; P<0.001) (Figure 2).

Regarding TAVI procedural details, both groups predominantly underwent the transfemoral approach (non-MACE group: 75.6%; MACE group: 56.0%). Concurrent PCI was performed in 6 patients in the non-MACE group and 2 patients in the MACE group. Immediate postoperative transesophageal echocardiography revealed paravalvular leakage in 44.7% of the non-MACE group and 56% of the MACE group, with over 90% of cases classified as mild.

Analysis of risk prediction for adverse cardiovascular events

As shown in Table 2, univariate Cox analysis identified multiple potential predictors associated with MACEs after TAVI, including NYHA classification, EuroSCORE II, hypertension, diabetes mellitus, CAD, PCI, BNP, relative wall thickness (RWT), LAVI, LVGLS, LASr, LACI, and TRPG. Based on a comprehensive consideration of the data characteristics of this study (a small number of positive cases and a large number of potential prognostic factors) and statistical reliability, we constructed three models for multivariate Cox proportional hazards analysis by incorporating basic clinical variables, traditional cardiac function parameters, and other relevant factors (Table 3). This approach was adopted to avoid insufficient test power that would violate the proportional hazards assumption and the risk of overfitting in a single model; in this way, we could determine the association pattern of prognostic factors more robustly. Multivariate Cox analysis showed that LACI remained significantly and independently associated with MACEs after adjustments were made for key variables such as age, sex, EuroSCORE II, and BNP (Model 1); NYHA classification ≥ III, hypertension, CAD, and diabetes mellitus (Model 2); and LVGLS, LAVI, LASr, and TRPG (Model 3).

ROC curve analysis was performed for five echocardiographic parameters of left heart function: LACI, LASr, LAVI, E/e’, and LVGLS; as shown in Figure 3A, their respective AUCs for predicting MACEs were 0.805, 0.761, 0.634, 0.723, and 0.736 (Figure 3A). After the DeLong test was performed, the LACI showed no statistically significant difference in discriminative ability as compared to classical diastolic function indicators (i.e., LASr, LAVI, E/e’, and LVGLS). The optimal cutoff value for LACI derived from the maximum Youden index was 28% (sensitivity 92%; specificity 56.9%). Patients were divided into two groups based on this threshold: the preserved LACI group (<28%; n=67) and the impaired LACI group (≥28%; n=81). Kaplan-Meier analysis revealed significantly lower MACE risk in the preserved LACI Group than in the impaired LACI group (log-rank test P<0.001) (Figure 3B).

Figure 3 Survival analysis of the LACI in patients with TAVI. Receiver operating characteristic curve analysis of LACI, LASr, LAVI, E/e', and LVGLS for predicting MACEs (A). Kaplan-Meier curves for MACEs in patients undergoing TAVI with LACI ≥28% or LACI <28% (B). AUC, area under the curve; CI, confidence interval; e', early diastolic mitral annular velocity; E, early mitral inflow velocity; LACI, left atrioventricular coupling index; LASr, left atrial longitudinal strain during the reservoir phase; LAVI, left atrial volume index; LVGLS, left ventricular global longitudinal strain; MACE, major adverse cardiac event; TAVI, transcatheter aortic valve implantation.

Reproducibility assessment

All measured parameters demonstrated excellent intraobserver and interobserver reproducibility. Among these, the LACI, the primary focus of this study, yielded an intra-observer intraclass correlation coefficient (ICC) of 0.904 [95% confidence interval (CI): 0.845–0.968] and an interobserver ICC of 0.913 (95% CI: 0.882–0.973).

Discussion

This study examined the value of echocardiography-derived LACI for predicting adverse cardiovascular events in patients undergoing TAVI. The principal findings were as follows: LACI is an independent risk factor for adverse cardiac events in patients treated with TAVI. Patients exhibiting left atrioventricular decoupling (LACI ≥28%) appear to have an elevated risk of MACEs. The predictive performance of LACI was noninferior to conventional LV diastolic dysfunction parameters.

AS involves pathophysiological changes in both the valvular and extravalvular structures. The mechanical obstruction caused by AS results in persistent afterload elevation on the LV. This triggers concentric hypertrophy through cardiomyocyte hypertrophy and interstitial fibrosis (increased collagen deposition) (23). During the compensatory phase, hypertrophied myocardium maintains ejection fraction by reducing wall stress but is accompanied by impaired diastolic relaxation. Prolonged afterload elevation increases myocardial stiffness, reduces LV compliance, and ultimately elevates LV end-diastolic pressure, culminating in diastolic dysfunction (24). Evidence of LA and LV functional and structural impairments has confirmed concomitant chamber remodeling throughout AS disease progression (25).

TAVI can immediately improve cardiac loading conditions, leading to functional and structural changes (26). Previous follow-up studies have confirmed that TAVI promotes reverse remodeling of the LV and LA, and improves LV relaxation function while reducing LA filling pressure. Cardiac magnetic resonance indicates decreased LVEDD and mean wall thickness within 6–15 months after TAVI (27). Furthermore, cardiac catheterization and cardiac magnetic resonance studies have reported a 43% increase in coronary flow reserve after TAVI, which significantly correlates with improved diastolic function (reduced E/e’) (28). This suggests that TAVI may immediately relieve valvular mechanical obstruction, reduce ventricular wall stress, reverse myocardial hypertrophy to remodel ventricles, and improve LV diastolic function through the restoration of diastolic myocardial perfusion and decreased LV filling pressure.

Multiple studies have examined the associations between LA/LV structural and functional dysfunction and adverse clinical outcomes after TAVI (1). Parameters such as E/e’, LAVI, and LA-LV strain have been identified as independent risk factors for poor clinical outcomes (29-31). Given the inherent coupling between LA and LV throughout the cardiac cycle, left atrioventricular coupling may better reflect combined atrioventricular dysfunction. Fortuni et al. found that the LACI correlated with LV diastolic dysfunction severity and served as an independent prognostic predictor in patients with heart failure, proposing LACI as a novel diastolic parameter (11). In patients with hypertrophic cardiomyopathy, echocardiography-derived LACI also demonstrated superior predictive value for new-onset atrial fibrillation as compared to traditional LA parameters (15). Consistent with prior findings, our study showed a higher LACI in patients treated with TAVI who experienced MACEs, indicating that left atrioventricular decoupling is associated with adverse outcomes. The elevated MACE risk in patients with baseline decoupling may be related to delayed or incomplete recovery of atrioventricular coupling post-TAVI, although mechanistic analysis and longitudinal data are needed to establish causality. Notably, the predictive performance of LACI was noninferior to that of conventional diastolic dysfunction parameters (including LASr, LAVI, E/e’, and LVGLS), aligning with previous research (32). The relatively rapid calculation of LACI compared to time-consuming strain analysis supports its potential as a cost-effective and time-efficient imaging parameter with significant prognostic utility.

In patients with AS, sustained elevation of LV afterload leads to alterations in LV geometry and mechanics (33,34). Elevated LV filling pressure negatively impacts LA function through hemodynamic overload and mechanical stretching of the LV wall, driving progressive LA enlargement and remodeling to maintain adequate LV filling (35). During early diastole, passive LA emptying generates a vortex flow that accumulates kinetic energy, promoting ventricular expansion. In late diastole, active LA contraction further augments LV preload. This process depends on the balance between LA compliance and LV filling pressure. The LACI can essentially capture the dynamic interaction between the LA and LV during ventricular diastole. By quantifying volume mismatch, LACI reflects the integrity of atrioventricular coupling.

Elevated LACI indicates that the LA requires greater volume compensation for increased ventricular filling resistance. This decoupled state accelerates LA dilation and functional decompensation, ultimately precipitating heart failure or arrhythmias. In patients with TAVI and LA-LV volume mismatch, reduced vortex strength or abnormal flow patterns may impair optimal LV preload, decreasing cardiac output and increasing cardiovascular risk. The prognostic value of LACI may be explained by its measurement timing coinciding with the critical vortex formation phase during ventricular diastole.

However, the concept of atrioventricular coupling is complex, and LACI may not fully capture all nuances of this relationship. Additionally, LACI uses two-dimensional measurements of LA and LV volumes, which may underestimate true volumes. Furthermore, valvular abnormalities affect LV and RV parameters, including the LACI, by altering ventricular load status (e.g., increased LV afterload caused by AS and elevated RV preload caused by TR) and disrupting hemodynamic characteristics (e.g., abnormal transmission of intracardiac pressure caused by regurgitation and volume overload). This interference impairs the interpretation of these parameters and their ability to accurately reflect the true cardiac function status. For instance, in patients with significant TR, the critical values of right cardiac function parameters associated with excessively high mortality (such as tricuspid annular plane systolic excursion and systolic peak velocity) are lower than those in patients without significant TR (36). Although the prognostic value of LACI has been verified in this study, its independent prognostic ability should still be viewed rationally. A comprehensive analysis incorporating multiple parameters is required to evaluate the prognosis of patients with AS. Although LACI cannot entirely replace LA-LV strain parameters in prognostic assessment, it provides unique insights into atrioventricular volume mismatch and coupling dynamics.

Additionally, due to the anatomical proximity of the atrioventricular node and the bundle of His, conduction abnormalities occurring after TAVI may result from mechanical trauma during the procedure. Consequently, TAVI-induced bradyarrhythmias are indeed more common. However, in this study, tachyarrhythmias were defined as malignant arrhythmias requiring intervention. Both the literature (37) and our observations include such patients, and thus the study outcomes were not limited to bradyarrhythmia cases. Valve-related variables were excluded given that early valve dysfunction remains uncommon (bioprosthetic failure rate <1%/year; prevalence of more-than-moderate paravalvular leak <5%), and no such events have been observed during follow-up in previous studies (38,39).

Notably, we observed one case of high-grade atrioventricular block occurring 6 months after TAVI, for which we propose the following explanation: First, AS itself may induce irreversible alterations through compensatory LV remodeling, including myocardial fibrosis, while fibrosis can establish an arrhythmogenic substrate for atrioventricular block; furthermore, preexisting right bundle branch block elevates the risk of postprocedural high-grade atrioventricular block (40). Second, post-TAVI restoration of LA and LV structure and function indicates reverse chamber remodeling (41,42). Since this atrioventricular block manifested at 6 months postoperatively and case reports include complete atrioventricular block months after TAVI, the atrioventricular block was likely a result of LV reverse remodeling causing relative prosthetic oversizing (43). We speculate that this case of atrioventricular block was unrelated to procedural trauma. However, these observations require confirmation through prospective verification.

Limitations

This study involved several limitations that should be acknowledged. First, the statistical requirements for incremental modeling with continuous data input might not have been fully met, given the multifactorial nature of prognostic risks in patients with TAVI, the slow patient recruitment, the limited study sample size, and the single-center nature of the design. A static model based on the full dataset was thus employed to prioritize parameter stability. Second, the use of simple ROC analysis instead of time-dependent ROC analysis was driven by practical considerations: the observed number of MACEs (n=25) and the heterogeneous follow-up duration (IQR, 6–27 months) might not adequately support the event density assumptions of time-dependent methods. Parametric models could introduce bias under such variability, whereas simple ROC analysis is less sensitive to censored data. While the AUC of 0.805 from simple ROC met clinical discrimination needs, future multicenter studies with larger cohorts are necessary to validate these findings and enable dynamic modeling.

Notably, this study did not examine preoperative-to-postoperative changes in left atrioventricular coupling parameters, which might better reflect the pathophysiological progression of decoupling. Incorporating postoperative parameter dynamics could enhance the clinical relevance of LACI. Furthermore, as the median follow-up period was 13 months, we cannot draw conclusions regarding LACI’s predictive value for long-term adverse cardiovascular outcomes. Despite these limitations, our findings suggest a potential association between elevated LACI and increased cardiovascular risk in patients with TAVI, highlighting the need for further investigation with extended follow-up and larger cohorts.

Conclusions

In patients undergoing TAVI, the LACI was independently associated with MACE occurrence. The predictive performance of LACI was noninferior to that of conventional LV diastolic dysfunction parameters. These findings should be further validated through multicenter studies with extended follow-up periods to further establish the clinical utility of the LACI.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://qims.amegroups.com/article/view/10.21037/qims-2025-989/rc

Data Sharing Statement: Available at https://qims.amegroups.com/article/view/10.21037/qims-2025-989/dss

Funding: This study was funded by the Key Program of Guangxi Natural Science Foundation (grant No. 2022JJD140147), the National Clinical Key Specialty Construction Project of China (Department of Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University), and the Clinical Key Specialty Construction Project of Guangxi (Department of Cardiothoracic Surgery, The First Affiliated Hospital of Guangxi Medical University).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-989/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study protocol was approved by The First Affiliated Hospital of Guangxi Medical University ethics committee (Approval No. 2025-E0252). All patients provided written informed consent after being fully informed about TAVI-specific risks, alternative treatments, and pre-/post-procedural data collection.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Emelianova M, Sciacca V, Brinkmann R, Scholtz S, Rudolph V, Bleiziffer S, Rudolph TK, Gerçek M, Vanezi M. Impact of left ventricular end-diastolic pressure as a marker for diastolic dysfunction on long-term outcomes in patients undergoing transcatheter aortic valve replacement. Hellenic J Cardiol 2024;80:4-11. [Crossref] [PubMed]
2. Zsarnoczay E, Varga-Szemes A, Schoepf UJ, Rapaka S, Pinos D, Aquino GJ, Fink N, Vecsey-Nagy M, Tremamunno G, Kravchenko D, Hagar MT, Amoroso NS, Steinberg DH, Jacob A, O'Doherty J, Sharma P, Maurovich-Horvat P, Emrich T. Predicting mortality after transcatheter aortic valve replacement using AI-based fully automated left atrioventricular coupling index. J Cardiovasc Comput Tomogr 2025;19:201-7. [Crossref] [PubMed]
3. Puls M, Beuthner BE, Topci R, Vogelgesang A, Bleckmann A, Sitte M, Lange T, Backhaus SJ, Schuster A, Seidler T, Kutschka I, Toischer K, Zeisberg EM, Jacobshagen C, Hasenfuß G. Impact of myocardial fibrosis on left ventricular remodelling, recovery, and outcome after transcatheter aortic valve implantation in different haemodynamic subtypes of severe aortic stenosis. Eur Heart J 2020;41:1903-14. [Crossref] [PubMed]
4. Généreux P, Sharma RP, Cubeddu RJ, Aaron L, Abdelfattah OM, Koulogiannis KP, Marcoff L, Naguib M, Kapadia SR, Makkar RR, Thourani VH, van Boxtel BS, Cohen DJ, Dobbles M, Barnhart GR, Kwon M, Pibarot P, Leon MB, Gillam LD. The Mortality Burden of Untreated Aortic Stenosis. J Am Coll Cardiol 2023;82:2101-9. [Crossref] [PubMed]
5. Eggebrecht H, Mehta RH. Transcatheter aortic valve implantation (TAVI) in Germany 2008-2014: on its way to standard therapy for aortic valve stenosis in the elderly? EuroIntervention 2016;11:1029-33. [Crossref] [PubMed]
6. Otto CM, Nishimura RA, Bonow RO, Carabello BA, Erwin JP 3rd, Gentile F, Jneid H, Krieger EV, Mack M, McLeod C, O'Gara PT, Rigolin VH, Sundt TM 3rd, Thompson A, Toly C. 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation 2021;143:e35-71. [Crossref] [PubMed]
7. Bowdish ME, Habib RH, Kaneko T, Thourani VH, Badhwar V. Cardiac Surgery After Transcatheter Aortic Valve Replacement: Trends and Outcomes. Ann Thorac Surg 2024;118:155-62. [Crossref] [PubMed]
8. Bana A. TAVR-present, future, and challenges in developing countries. Indian J Thorac Cardiovasc Surg 2019;35:473-84. [Crossref] [PubMed]
9. Gjertsson P, Caidahl K, Farasati M, Odén A, Bech-Hanssen O. Preoperative moderate to severe diastolic dysfunction: a novel Doppler echocardiographic long-term prognostic factor in patients with severe aortic stenosis. J Thorac Cardiovasc Surg 2005;129:890-6. [Crossref] [PubMed]
10. Asami M, Lanz J, Stortecky S, Räber L, Franzone A, Heg D, Hunziker L, Roost E, Siontis GC, Valgimigli M, Windecker S, Pilgrim T. The Impact of Left Ventricular Diastolic Dysfunction on Clinical Outcomes After Transcatheter Aortic Valve Replacement. JACC Cardiovasc Interv 2018;11:593-601. [Crossref] [PubMed]
11. Fortuni F, Biagioli P, Myagmardorj R, Mengoni A, Chua AP, Zuchi C, Sforna S, Bax J, Ajmone Marsan N, Ambrosio G, Carluccio E. Left Atrioventricular Coupling Index: A Novel Diastolic Parameter to Refine Prognosis in Heart Failure. J Am Soc Echocardiogr 2024;37:1038-46. [Crossref] [PubMed]
12. Pezel T, Venkatesh BA, De Vasconcellos HD, Kato Y, Shabani M, Xie E, Heckbert SR, Post WS, Shea SJ, Allen NB, Watson KE, Wu CO, Bluemke DA, Lima JAC. Left Atrioventricular Coupling Index as a Prognostic Marker of Cardiovascular Events: The MESA Study. Hypertension 2021;78:661-71. [Crossref] [PubMed]
13. Zornitzki L, Topilsky Y. Left Atrioventricular Coupling Index: When Minimal Left Atrial Volume Is Actually 'More' Than Maximal Left Atrial Volume. J Am Soc Echocardiogr 2024;37:1047-50. [Crossref] [PubMed]
14. Lange T, Backhaus SJ, Schulz A, Evertz R, Kowallick JT, Bigalke B, Hasenfuß G, Thiele H, Stiermaier T, Eitel I, Schuster A. Cardiovascular magnetic resonance-derived left atrioventricular coupling index and major adverse cardiac events in patients following acute myocardial infarction. J Cardiovasc Magn Reson 2023;25:24. [Crossref] [PubMed]
15. Meucci MC, Fortuni F, Galloo X, Bootsma M, Crea F, Bax JJ, Marsan NA, Delgado V. Left atrioventricular coupling index in hypertrophic cardiomyopathy and risk of new-onset atrial fibrillation. Int J Cardiol 2022;363:87-93. [Crossref] [PubMed]
16. Kasa G, Teis A, De Raffele M, Cediel G, Juncà G, Lupón J, Santiago-Vacas E, Codina P, Bayés-Genis A, Delgado V. Prognostic value of left atrioventricular coupling index in heart failure. Eur Heart J Cardiovasc Imaging 2025;26:610-7. [Crossref] [PubMed]
17. Fan J, Wang H, Ma C, Zhou B. Characteristics of atrial ventricular coupling and left atrial function impairment in early Fabry disease patients using two-dimensional speckle tracking echocardiography. Int J Cardiol 2025;422:132967. [Crossref] [PubMed]
18. Gao X, Xie A, Xiao W, Ji L, Li H, Zou A, Miao Z, Zhang X, Yang S, Yu S. A novel index evaluating left atrioventricular coupling function in chronic kidney disease with diabetes patients. Sci Rep 2025;15:8402. [Crossref] [PubMed]
19. Sengupta PP, Narula J À. LA mode atrioventricular mechanical coupling. JACC Cardiovasc Imaging 2014;7:109-11. [Crossref] [PubMed]
20. Lang RM, Badano LP, Mor-Avi V, Afilalo J, Armstrong A, Ernande L, Flachskampf FA, Foster E, Goldstein SA, Kuznetsova T, Lancellotti P, Muraru D, Picard MH, Rietzschel ER, Rudski L, Spencer KT, Tsang W, Voigt JU. Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr 2015;28:1-39.e14. [Crossref] [PubMed]
21. Nagueh SF, Smiseth OA, Appleton CP, Byrd BF 3rd, Dokainish H, Edvardsen T, Flachskampf FA, Gillebert TC, Klein AL, Lancellotti P, Marino P, Oh JK, Popescu BA, Waggoner AD. Recommendations for the Evaluation of Left Ventricular Diastolic Function by Echocardiography: An Update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr 2016;29:277-314. [Crossref] [PubMed]
22. Généreux P, Piazza N, Alu MC, Nazif T, Hahn RT, et al. Valve Academic Research Consortium 3: updated endpoint definitions for aortic valve clinical research. Eur Heart J 2021;42:1825-57. [Crossref] [PubMed]
23. Thaden JJ, Nkomo VT, Enriquez-Sarano M. The global burden of aortic stenosis. Prog Cardiovasc Dis 2014;56:565-71. [Crossref] [PubMed]
24. Fukui M, Gupta A, Abdelkarim I, Sharbaugh MS, Althouse AD, Elzomor H, Mulukutla S, Lee JS, Schindler JT, Gleason TG, Cavalcante JL. Association of Structural and Functional Cardiac Changes With Transcatheter Aortic Valve Replacement Outcomes in Patients With Aortic Stenosis. JAMA Cardiol 2019;4:215-22. [Crossref] [PubMed]
25. Shamekhi J, Nguyen TQA, Sigel H, Maier O, Piayda K, Zeus T, Al-Kassou B, Weber M, Zimmer S, Sugiura A, Wilde N, Kelm M, Nickenig G, Veulemans V, Sedaghat A. Left atrial function index (LAFI) and outcome in patients undergoing transcatheter aortic valve replacement. Clin Res Cardiol 2022;111:944-54. [Crossref] [PubMed]
26. Dobson LE, Musa TA, Uddin A, Fairbairn TA, Swoboda PP, Erhayiem B, Foley J, Garg P, Haaf P, Fent GJ, Malkin CJ, Blackman DJ, Plein S, Greenwood JP. Acute Reverse Remodelling After Transcatheter Aortic Valve Implantation: A Link Between Myocardial Fibrosis and Left Ventricular Mass Regression. Can J Cardiol 2016;32:1411-8. [Crossref] [PubMed]
27. Mehdipoor G, Chen S, Chatterjee S, Torkian P, Ben-Yehuda O, Leon MB, Stone GW, Prince MR. Cardiac structural changes after transcatheter aortic valve replacement: systematic review and meta-analysis of cardiovascular magnetic resonance studies. J Cardiovasc Magn Reson 2020;22:41. [Crossref] [PubMed]
28. Beneduce A, Laforgia P, Tchétché D, Dumonteil N. Challenges and Limitations of Redo Transcatheter Aortic Valve Replacement Using Current Techniques. JACC Cardiovasc Interv 2023;16:1537-41. [Crossref] [PubMed]
29. Stens NA, van Iersel O, Rooijakkers MJP, van Wely MH, Nijveldt R, Bakker EA, Rodwell L, Pedersen ALD, Poulsen SH, Kjønås D, Stassen J, Bax JJ, Tanner FC, Lerakis S, Shimoni S, Poulin F, Ferreira V, Reskovic Luksic V, van Royen N, Thijssen DHJ. Prognostic Value of Preprocedural LV Global Longitudinal Strain for Post-TAVR-Related Morbidity and Mortality: A Meta-Analysis. JACC Cardiovasc Imaging 2023;16:332-41. [Crossref] [PubMed]
30. von Roeder M, Maeder M, Wahl V, Kitamura M, Rotta Detto Loria J, Dumpies O, Rommel KP, Kresoja KP, Blazek S, Richter I, Majunke N, Desch S, Thiele H, Lurz P, Abdel-Wahab M. Prognostic significance and clinical utility of left atrial reservoir strain in transcatheter aortic valve replacement. Eur Heart J Cardiovasc Imaging 2024;25:373-82. [Crossref] [PubMed]
31. Lee CY, Tsai CM, Chiang KC, Huang CC, Lin MS, Hung CL, Ho YL, Nkomo VT, Takeuchi M, Yang LT. Prognostic value of left ventricular and left atrial strain imaging in moderate to severe aortic stenosis: Insights from an Asian population. Int J Cardiol 2024;407:132103. [Crossref] [PubMed]
32. Lee HJ, Kim K, Gwak SY, Cho I, Hong GR, Ha JW, Shim CY. Incremental prognostic value of left ventricular and left atrial strains in moderate aortic stenosis. Eur Heart J Cardiovasc Imaging 2024;26:96-103. [Crossref] [PubMed]
33. Otto CM, Newby DE, Hillis GS. Calcific Aortic Stenosis: A Review. JAMA 2024;332:2014-26. [Crossref] [PubMed]
34. Myon F, Marut B, Kosmala W, Auffret V, Leurent G, L'official G, Curtis E, Le Breton H, Oger E, Donal E. Transcatheter aortic valve implantation in severe aortic stenosis does not necessarily reverse left ventricular myocardial damage: data of long-term follow-up. Eur Heart J Cardiovasc Imaging 2024;25:821-8. [Crossref] [PubMed]
35. Delgado V, Kumbhani DJ. Cardiac and Vascular Changes After Transcatheter or Surgical Aortic Valve Replacement in Low-Risk Aortic Stenosis. Circulation 2020;141:1538-40. [Crossref] [PubMed]
36. Zornitzki L, Freund O, Frydman S, Rozenbaum Z, Granot Y, Banai S, Topilsky Y. Mortality-Based Right Ventricle Functional Echocardiographic Cutoffs in Patients With Compared to Without Tricuspid Regurgitation. J Am Soc Echocardiogr 2025;38:228-35. [Crossref] [PubMed]
37. Natarajan MK, Sheth TN, Wijeysundera HC, Chavarria J, Rodes-Cabau J, Velianou JL, Radhakrishnan S, Newman T, Smith A, Wong JA, Schwalm JD, Duong M, Mian RI, Bishop MG, Healey JS. Remote ECG monitoring to reduce complications following transcatheter aortic valve implantations: the Redirect TAVI study. Europace 2022;24:1475-83. [Crossref] [PubMed]
38. Thyregod HGH, Ihlemann N, Jørgensen TH, Nissen H, Kjeldsen BJ, Petursson P, Chang Y, Franzen OW, Engstrøm T, Clemmensen P, Hansen PB, Andersen LW, Steinbruüchel DA, Olsen PS, Søndergaard L. Five-Year Clinical and Echocardiographic Outcomes From the NOTION Randomized Clinical Trial in Patients at Lower Surgical Risk. Circulation 2019;139:2714-23. [Crossref] [PubMed]
39. Zito A, Buono A, Scotti A, Kim WK, Fabris T, de Biase C, et al. Incidence, Predictors, and Outcomes of Paravalvular Regurgitation After TAVR in Sievers Type 1 Bicuspid Aortic Valves. JACC Cardiovasc Interv 2024;17:1652-63. [Crossref] [PubMed]
40. Egger F, Nürnberg M, Rohla M, Weiss TW, Unger G, Smetana P, Geppert A, Gruber SC, Bambazek A, Falkensammer J, Waldenberger FR, Huber K, Freynhofer MK. High-degree atrioventricular block in patients with preexisting bundle branch block or bundle branch block occurring during transcatheter aortic valve implantation. Heart Rhythm 2014;11:2176-82. [Crossref] [PubMed]
41. D'Ascenzi F, Cameli M, Henein M, Iadanza A, Reccia R, Lisi M, Curci V, Sinicropi G, Torrisi A, Pierli C, Mondillo S. Left atrial remodelling in patients undergoing transcatheter aortic valve implantation: a speckle-tracking prospective, longitudinal study. Int J Cardiovasc Imaging 2013;29:1717-24. [Crossref] [PubMed]
42. D'Andrea A, Padalino R, Cocchia R, Di Palma E, Riegler L, Scarafile R, Rossi G, Bianchi R, Tartaglione D, Cappelli Bigazzi M, Calabrò P, Citro R, Bossone E, Calabrò R, Russo MG. Effects of transcatheter aortic valve implantation on left ventricular and left atrial morphology and function. Echocardiography 2015;32:928-36. [Crossref] [PubMed]
43. Segreti L, Ujka K, Cellamaro T, Zucchelli G, Di Cori A, Soldati E, Bongiorni MG. Left ventricular reverse remodeling after transcatheter aortic valve implantation complicated by paroxysmal complete atrioventricular block. J Cardiol Cases 2018;17:194-6. [Crossref] [PubMed]