Prognostic Impact of Right Ventricular Strain in Isolated Severe Tricuspid Regurgitation

Valvular heart disease: from mechanisms to management

Valvular heart disease is common and its prevalence is rapidly increasing worldwide. Effective medical therapies are insufficient and treatment was historically limited to the surgical techniques of valve repair or replacement, resulting in systematic underprovision of care to older patients and those with substantial comorbidities, frailty, or left ventricular dysfunction. Advances in imaging and surgical techniques over the past 20 years have transformed the management of valvular heart disease. Better understanding of the mechanisms and causes of disease and an increasingly extensive and robust evidence base provide a platform for the delivery of individualised treatment by multidisciplinary heart teams working within networks of diagnostic facilities and specialist heart valve centres. In this Series paper, we aim to provide an overview of the current and future management of valvular heart disease and propose treatment approaches based on an understanding of the underlying pathophysiology and the application of multidisciplinary treatment strategies to individual patients.

Circulating miRNA in functional tricuspid regurgitation. Unveiling novel links to heart failure: A pilot study

AIM

Severe functional tricuspid regurgitation (FTR) is associated with high risk of cardiovascular events, particularly heart failure (HF) and mortality. MicroRNAs (miRNAs) have been recently identified as novel biomarkers in different cardiovascular conditions, but no studies have focused on FTR. We sought to (1) to identify and validate circulating miRNAs as regulators of FTR and (2) to test association of miRNA with heart failure and mortality in FTR.

METHODS AND RESULTS

Consecutive patients with isolated severe FTR (n = 100) evaluated in the outpatient Heart Valve Clinic and age- and gender-matched subjects with no TR (controls, n = 50) were prospectively recruited. The experimental design included (1) a screening phase to identify candidate miRNA differentially expressed in FTR (n = 8) compared with controls (n = 8) through miRNA array profiling of 192 miRNAs using quantitative reverse transcription PCR arrays [qRT-PCR]) and (2) a validation phase in which candidate miRNAs identified in the initial screening were selected for further validation by qRT-PCR in a prospectively recruited cohort of FTR (n = 92) and controls (n = 42). Bioinformatics analysis was used to predict their potential target genes and functional pathways elicited. A combined endpoint of hospital admission due to heart failure (HF) and all-cause mortality was defined. Initial screening identified 16 differentially expressed miRNAs in FTR compared with controls, subsequently confirmed in the validation phase (n = 16 were excluded due to significant haemolysis). miR-186-5p, miR-30e-5p, and miR-152-3p identified FTR with high predictive value [AUC of 0.93 (0.88-0.97), 0.83 (0.75-0.91) and 0.84 (0.76-0.92), respectively]. During a median follow-up of 20.4 months (IQR 8-35 months), 32% of FTR patients reached the combined endpoint. Patients with low relative expression of miR-15a-5p, miR-92a-3p, miR101-3p, and miR-363-3p, miR-324-3p, and miR-22-3p showed significantly higher rates of events (log-rank test for all P < 0.01). Both miR-15a-5p [hazard ratio: 0.21 (0.06-0.649, P = 0.007) and miR-92a-3p (0.27 (0.09-0.76), P = 0.01] were associated with outcomes after adjusting for age, gender, and New York Heart Association functional class.

CONCLUSIONS

Circulating miRNAs are novel diagnostic and prognostic biomarkers in severe FTR. The quantification of miR-186-5p, miR-30e-5p, and miR-152-3p held strong diagnostic value, and the quantification of miR-15a-5p and miR-92a-3p are independently associated with outcomes. The recognition of specific miRNAs offers a novel perspective for TR evaluation.

Prognostic Implication of Right Ventricular Free Wall Longitudinal Strain and Right Atrial Pressure Estimated By Echocardiography in Patients With Severe Functional Tricuspid Regurgitation

BACKGROUND

The interaction between right ventricular (RV) function and pulmonary hypertension is crucial for prognosis of patients with severe functional tricuspid regurgitation. RV free wall longitudinal strain (RVFWLS) has been reported to detect RV systolic dysfunction earlier than other conventional parameters. Although pulmonary artery systolic pressure measured by Doppler echocardiography is often underestimated in severe functional tricuspid regurgitation, right atrial pressure (RAP) estimated by echocardiography may be viewed as a prognostic factor. Impact of RAP and RVFWLS on outcome in patients with severe functional tricuspid regurgitation remains unclear. The aim of the present study was to investigate prognostic implication of RAP, RVFWLS, and their combination in this population.

METHODS AND RESULTS

We retrospectively examined 377 patients with severe functional tricuspid regurgitation. RAP, pulmonary artery systolic pressure, RV fractional area change, and RVFWLS were analyzed. RAP of 15 mm Hg was classified as elevated RAP. All-cause death at 2-year follow-up was defined as the primary end point. RVFWLS provided better prognostic information than RV fractional area change by receiver operating characteristic curve analysis. In the multivariable Cox regression analysis, elevated RAP and RVFWLS of ≤18% were independent predictors of clinical outcome. Patients with RVFWLS of ≤18% had higher risk of all-cause death than those without by Kaplan-Meier curve analysis. Furthermore, when patients were stratified into 4 groups by RAP and RVFWLS, the group with elevated RAP and RVFWLS of ≤18% had the worst outcome.

CONCLUSIONS

Elevated RAP and RVFWLS of ≤18% were independent predictors of all-cause death. The combination of elevated RAP and RVFWLS effectively stratified the all-cause death.

Validation of TRI-SCORE for Outcome Prediction After Isolated Tricuspid Valve Surgery in Asian Patients

BACKGROUND

TRI-SCORE was recently developed in Europe as a risk model for predicting in-hospital death after isolated tricuspid valve surgery. We aimed to validate TRI-SCORE in an Asian population and investigate its value for predicting long-term outcomes.

METHODS AND RESULTS

The TRI-SCORE was calculated for 202 patients (65±11 years, 61% women, 81% functional tricuspid regurgitation) who underwent isolated tricuspid valve surgery for severe tricuspid regurgitation at 2 Korean centers and was based on 8 parameters: age, New York Heart Association class, right-sided heart failure signs, furosemide daily dose, glomerular filtration rate, bilirubin, left ventricular ejection fraction, and moderate/severe right ventricular dysfunction. The primary outcome was all-cause death during follow-up; the secondary outcome was in-hospital death. During a median follow-up duration of 50 (interquartile range, 21-82) months after isolated tricuspid valve surgery, 23 (11.4%) patients experienced the primary outcome, and 7 (3.5%) patients experienced the secondary outcome. Observed all-cause death and in-hospital death increased by up to 50% in those with higher scores. Patients with the primary outcome had a higher TRI-SCORE (4.5±2.4 versus 2.9±2.1; P=0.001) than those without. The TRI-SCORE showed a significant association with the primary outcome (concordance index, 0.77, cutoff value, 4) and in-hospital death (area under the curve, 0.84; cutoff value, 3). Using the Kaplan-Meier analysis, patients with a high TRI-SCORE exhibited a poor outcome for all-cause death at follow-up (log-rank P<0.001) and in-hospital death (log-rank P=0.004).

CONCLUSIONS

TRI-SCORE was validated in an Asian population and helped predict long-term outcomes after isolated tricuspid valve surgery.

New Approaches to Assessment and Management of Tricuspid Regurgitation Before Intervention

Severe tricuspid regurgitation (TR) is a progressive condition associated with substantial morbidity, poor quality of life, and increased mortality. Patients with TR commonly have coexisting conditions including congestive heart failure, pulmonary hypertension, chronic lung disease, atrial fibrillation, and cardiovascular implantable electronic devices, which can increase the complexity of medical and surgical TR management. As such, the optimal timing of referral for isolated tricuspid valve (TV) intervention is undefined, and TV surgery has been associated with elevated risk of morbidity and mortality. More recently, an unprecedented growth in TR treatment options, namely the development of a wide range of transcatheter TV interventions (TTVI) is stimulating increased interest and referral for TV intervention across the entire medical community. However, there are no stepwise algorithms for the optimal management of symptomatic severe TR before TTVI. This article reviews the contemporary assessment and management of TR with addition of a medical framework to optimize TR before referral for TTVI.

STREI: a new index of right heart function in isolated severe tricuspid regurgitation by speckle-tracking echocardiography

AIMS

Right ventricular (RV) performance determines clinical management in severe tricuspid regurgitation (TR). Right atrial (RA) function complements RV assessment in TR. This study aimed to design a novel index by speckle-tracking echocardiography (STREI index) integrating RA and RV strain information and to evaluate the clinical utility of combining RV and RA strain for prediction of cardiovascular (CV) outcomes.

METHODS AND RESULTS

Consecutive patients with at least (≥) severe TR evaluated in the Heart Valve Clinic (n = 300) were prospectively included. An additional independent TR cohort was included for external validation (n = 50). STREI index was developed with the formula: [2 ∗ RV-free wall longitudinal strain (RV-FWLS)] + reservoir RA strain (RASr). The composite endpoint included hospital admission due to heart failure and all-cause mortality. A total of 176 patients with ≥severe TR were finally included. STREI index identified a higher percentage of patients with RV dysfunction compared with conventional parameters. After a median follow-up of 2.2 years (interquartile range: 12-41 months), a total of 38% reached the composite endpoint. STREI values were predictors of outcomes independently of TR severity and RV dimensions. The combination of prognostic cut-off values of RASr (<10%) and RV-FWLS (>-20%) (STREI stratification) stratified four different groups of risk independently of TR severity, RV dimensions, and clinical status (adj HR per stratum 1.89 (1.4-2.34), P < 0.001). Pre-defined cut-off values achieved similar prognostic performance in the validation cohort (n = 50).

CONCLUSION

STREI index is a novel parameter of RV performance that independently predicts CV events. The combination of RA and RV strain stratifies better patients' risk, reflecting a broader effect of TR on right heart chambers.

Contemporary Approach to Tricuspid Regurgitation: Knowns, Unknowns, and Future Challenges

Severe tricuspid regurgitation (TR) worsens heart failure and is associated with impaired survival. In daily clinical practice, patients are referred late, and tricuspid valve interventions (surgical or transcatheter) are underutilised, which may lead to irreversible right ventricular damage and increases risk. This article addresses the appropriate timing and modality for an intervention (surgical or transcatheter), and its potential benefits on clinical outcomes. Ongoing randomised controlled trials will provide further insights into the efficacy of transcatheter valve interventions compared with medical treatment.

The Contemporary Role of Speckle Tracking Echocardiography in Cirrhotic Cardiomyopathy

Cirrhotic cardiomyopathy (CCM) is characterized by elevated cardiac output at rest, an inability to further increase contractility under stress, and diastolic dysfunction. The diagnosis of CCM is crucial as it can lead to complications during liver transplantation. However, its recognition poses challenges with conventional echocardiography techniques. Speckle tracking echocardiography (STE), particularly global longitudinal strain (GLS), is a novel index that enhances the diagnostic efficacy of echocardiography for both ischemic and non-ischemic cardiomyopathies. GLS proves more sensitive in identifying early systolic dysfunction and is also influenced by advanced diastolic dysfunction. Consequently, there is an expanding scope for GLS utilization in cirrhotic cases, with newly updated diagnostic criteria for CCM incorporating GLS. Specifically, systolic dysfunction is now defined as either a left ventricular ejection fraction below 50% or an absolute GLS below 18%. However, conflicting data on GLS alterations in liver cirrhosis patients persist, as many individuals with advanced disease and a poor prognosis exhibit a hyperdynamic state with preserved or increased GLS. Consequently, the presence of CCM, according to the updated criteria, does not exhibit a significant association-in the majority of studies-with the severity of liver disease and prognosis. Furthermore, information on other indices measured with STE, such as left atrial and right ventricular strain, is promising but currently limited. This review aims to offer a critical assessment of the existing evidence concerning the application of STE in patients with liver cirrhosis.

Unmet Needs in the Assessment of Right Ventricular Function for Severe Tricuspid Regurgitation

Tricuspid regurgitation (TR) is a highly prevalent valvular heart disease that has been long overlooked, but lately its independent association with adverse cardiovascular outcomes was recognized. The time point to intervene and repair the tricuspid valve is defined by the right ventricular (RV) dilation and dysfunction that comes up at a later stage. While guidelines favor tricuspid valve repair before severe RV dysfunction ensues, the definition of RV dysfunction in a universal manner remains vague. As a result, the candidates for transcatheter or surgical TR procedures are often referred late, when advanced RV dysfunction is established, and any derived procedural survival benefit is attenuated. Thus, it is of paramount importance to establish a universal means of RV function assessment in patients with TR. Conventional echocardiographic indices of RV function routinely applied have fundamental flaws that limit the precise characterization of RV performance. More recently, novel echocardiographic indices such as strain via speckle-tracking have emerged, demonstrating promising results in the identification of early RV damage. Additionally, evidence of the role of alternative imaging modalities such as cardiac computed tomography and cardiac magnetic resonance, for RV functional assessment in TR, has recently arisen. This review provides a systematic appraisal of traditional and novel multimodality indices of RV function in severe TR and aims to refine RV function assessment, designate future directions, and ultimately, to improve the outcome of patients suffering from severe TR.

Prognostic Performance of Right Ventricular Global Longitudinal Strain Measurements in Patients With Ebstein Anomaly

BACKGROUND

There are limited data on the prognostic role of right ventricular global longitudinal strain (RVGLS) in patients with Ebstein anomaly.

OBJECTIVES

This study sought to assess the relationship between RVGLS and mortality and to compare prognostic performance of RVGLS with conventional echocardiographic indices of right ventricular (RV) systolic function.

METHODS

This study identified adults with Ebstein anomaly with echocardiographic assessment of RV systolic function (RVGLS, RV fractional area change [RVFAC], RV tissue Doppler systolic velocity [RV s'], and tricuspid annular plane systolic excursion [TAPSE]) from 2003 to 2020. For ease of presentation, RVGLS was modeled as absolute values (ie, without the negative sign).

RESULTS

Of 620 patients (median age 37 years; men 261 [42%]), the mean absolute RVGLS, RVFAC, RV s', and TAPSE were 18% ± 5%, 32% ± 9%, 14 ± 6 cm/s, and 22 ± 8 mm, respectively. There were correlations between absolute RVGLS and RVFAC (r = 0.71; P < 0.001), between absolute RVGLS and RV s' (r = 0.41; P = 0.03), and between absolute RVGLS and TAPSE (r = 0.44; P = 0.002). Of 620 patients, 47 (8%) died during follow-up, and 34 of these deaths were cardiovascular. Absolute RVGLS was independently associated with all-cause mortality (adjusted HR: 0.94; 95% CI: 0.92-0.96 per unit increase) and cardiovascular mortality (adjusted HR: 0.92; 95% CI: 0.90-0.94 per unit increase). Absolute RVGLS had superior prognostic power (ie, ability to predict mortality) as compared with RVFAC, RV s', or TAPSE.

CONCLUSIONS

These data support the use of RVGLS for risk stratification in Ebstein anomaly, and further studies are required to assess how interventions may affect different patients according to risk stratification.