Assessment of right ventricular systolic function using speckle tracking strain imaging in patients with severe tricuspid regurgitation: a validation study with cardiac magnetic resonance

BACKGROUND

Right ventricular (RV) systolic dysfunction is an established prognostic factor in patients with severe tricuspid regurgitation (TR). However, accurate assessment of RV systolic function using conventional echocardiography remains challenging. We investigated the accuracy of strain measurement using speckle tracking echocardiography (STE) for evaluating RV systolic function in patients with severe TR.

METHODS

We included consecutive patients with severe TR who underwent echocardiography and cardiac magnetic resonance imaging (CMR) within 30 days between 2011 and 2023. Two-dimensional STE was used to measure RV free wall longitudinal strain (RVFWLS) and global longitudinal strain (RVGLS). These values were compared with the RV ejection fraction (RVEF) from CMR. RV systolic dysfunction was defined as a CMR-derived RVEF < 35%.

RESULTS

A total of 87 patients with severe TR were identified during the study period. Among echocardiographic RV strain measurements, RVFWLS was the best correlate of CMR-derived RVEF (r = -0.37, P < 0.001), followed by RVGLS (r = -0.27, P = 0.012). Receiver operating characteristic (ROC) curve analysis revealed that RVFWLS provided better discrimination of RV systolic dysfunction, yielding an area under the ROC curve (AUC) of 0.770 (95% confidence interval [CI], 0.696-0.800) than RV fractional area change (AUC, 0.615; 95% CI, 0.500-0.859).

CONCLUSIONS

In patients with severe TR, STE-derived RVFWLS showed the best correlation with RVEF on CMR and displayed superior discrimination of RV systolic dysfunction compared with the RV fractional area change. This study suggests the potential usefulness of STE in assessing RV systolic function in this population.

Assessment of Tricuspid Regurgitation by Cardiac Magnetic Resonance Imaging: Current Role and Future Applications

Tricuspid regurgitation (TR) is a prevalent valvular disease with a significant mortality rate. The evaluation of TR severity and associated right heart remodeling and dysfunction is crucial to determine the optimal therapeutic strategy and to improve prognosis. While echocardiography remains the first-line imaging technique to evaluate TR, it has many limitations, both operator- and patient-related. Cardiovascular magnetic resonance imaging (CMR) has emerged as an innovative and comprehensive non-invasive cardiac imaging technique with additional value beyond routine echocardiographic assessment. Besides its established role as the gold standard for the evaluation of cardiac volumes, CMR can add important insights with regard to valvular anatomy and function. Accurate quantification of TR severity, including calculation of regurgitant volume and fraction, can be performed using either the well-known indirect volumetric method or novel 4D flow imaging. In addition, CMR can be used to assess the impact on the right heart, including right heart remodeling, function and tissue characterization. Several CMR-derived parameters have been associated with outcome, highlighting the importance of multi-modality imaging in patients with TR. The aim of this review is to provide an overview of the current role of CMR in the assessment and management of patients with TR and its future applications.

2023 Korean Society of Echocardiography position paper for the diagnosis and management of valvular heart disease, part II: mitral and tricuspid valve disease

This manuscript represents the official position of the Korean Society of Echocardiography on valvular heart diseases. This position paper focuses on the diagnosis and management of valvular heart diseases with referring to the guidelines recently published by the American College of Cardiology/American Heart Association and the European Society of Cardiology. The committee sought to reflect national data on the topic of valvular heart diseases published to date through a systematic literature search based on validity and relevance. In the part II of this article, we intend to present recommendations for diagnosis and treatment of mitral valve disease and tricuspid valve disease.

Tricuspid Regurgitation: From Imaging to Clinical Trials to Resolving the Unmet Need for Treatment

Tricuspid regurgitation (TR) is a highly prevalent and heterogeneous valvular disease, independently associated with excess mortality and high morbidity in all clinical contexts. TR is profoundly undertreated by surgery and is often discovered late in patients presenting with right-sided heart failure. To address the issue of undertreatment and poor clinical outcomes without intervention, numerous structural tricuspid interventional devices have been and are in development, a challenging process due to the unique anatomic and physiological characteristics of the tricuspid valve, and warranting well-designed clinical trials. The path from routine practice TR detection to appropriate TR evaluation, to conduction of clinical trials, to enriched therapeutic possibilities for improving TR access to treatment and outcomes in routine practice is complex. Therefore, this paper summarizes the key points and methods crucial to TR detection, quantitation, categorization, risk-scoring, intervention-monitoring, and outcomes evaluation, particularly of right-sided function, and to clinical trial development and conduct, for both interventional and surgical groups.

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.

Multimodality imaging for transcatheter tricuspid valve repair and replacement

Transcatheter tricuspid intervention is a rapidly evolving field with multiple classes of therapeutic devices currently in development. Procedural success in tricuspid intervention is predicated on appropriate device selection for patient specific anatomy and satisfactory imaging for intra-procedural guidance. This review will outline protocols and methodology for multi-modality imaging assessment of the tricuspid valve and associated structures, with emphasis on anatomic and functional characteristics that determine suitability for each class of tricuspid intervention. Intra-procedural imaging requirements for each class of device, with design and procedural imaging guidance of specific devices, will also be addressed.

Utility of CT and MRI in Tricuspid Valve Interventions

Transcatheter tricuspid valve interventions (TTVIs) comprise a variety of catheter-based interventional techniques for treatment of tricuspid regurgitation (TR) in patients at high surgical risk and those with failed previous surgeries. Several TTVI devices with different mechanisms of action are either currently used or in preclinical evaluation. Echocardiography is the first-line modality for evaluation of tricuspid valve disease that provides information on tricuspid valve morphology, mechanism of TR, and hemodynamics. Cardiac CT and MRI have several advantages for a comprehensive preprocedure evaluation. CT and MRI provide complementary information to that of echocardiography on the mechanism and cause of TR. MRI can quantify the severity of TR using indirect or direct techniques that involve two-dimensional or four-dimensional flow sequences. MRI and CT can also accurately quantify right ventricular volumes and function, which is crucial for timing of intervention. CT provides comprehensive three-dimensional information on the morphology of the valve, annulus, subvalvular apparatus, and adjacent structures. CT is the procedure of choice for evaluation of several device-specific measurements, including tricuspid annulus dimensions, annulus-to-right coronary artery distance, leaflet morphology, coaptation gaps, caval dimensions, and cavoatrial-to-hepatic vein distance. CT allows evaluation of the vascular access as well as optimal procedure fluoroscopic angles and catheter trajectory. Postprocedure CT and MRI are useful in detection of complications such as paravalvular leak, pseudoaneurysm, thrombus, pannus, infective endocarditis, and device migration. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Tricuspid Regurgitation: Right Ventricular Volume Versus Pressure Load

PURPOSE OF THE REVIEW

Tricuspid regurgitation is associated with increased mortality in proportion to right ventricular adaptation to increased volume loading and pulmonary artery pressure. We here review recent progress in the understanding of right ventricular adaptation to pre- and after-loading conditions for improved recommendations of tricuspid valve repair.

RECENT FINDINGS

Trans-catheter tricuspid valve repair has made the correction of tricuspid regurgitation more easily available, triggering a need of tighter indications. Several studies have shown the feasibility and relevance to the indications of tricuspid valve repair of imaging of right ventricular ejection fraction measured by magnetic resonance imaging or 3D-echocardiography, and the 2D-echocardiography of the tricuspid annular plane systolic excursion to systolic pulmonary artery pressure ratio combined with invasively determined mean pulmonary artery pressure and pulmonary vascular resistance. Improved definitions of right ventricular failure and pulmonary hypertension may be considered in future recommendations on the treatment of tricuspid regurgitation.

Prognostic value of functional tricuspid regurgitation quantified by cardiac magnetic resonance in heart failure

AIMS

Quantitative assessment of tricuspid regurgitation (TR) is challenging, and the prognostic implications of cardiac magnetic resonance (CMR)-quantified measures of TR remain unclear in patients with heart failure with reduced ejection fraction (HFrEF). This study investigated the prognostic value of functional TR quantified by CMR in patients with HFrEF.

METHODS AND RESULTS

A total of 262 patients with HFrEF who underwent CMR were analysed. Patients who had primary TR, who had acute HF, or for whom cardiac surgery was planned were excluded. TR volume and fraction were indirectly calculated via subtracting methods. The primary outcome was defined as a composite of all-cause death and hospitalization for HF. Renal outcome was defined as a composite of a decrease in estimated glomerular filtration rate ≥50% or progression to end-stage renal disease. During the follow-up period (median 921 days), 62 primary outcomes and 48 renal outcomes occurred. When divided into two or three groups based on TR fraction in Kaplan-Meier analysis, patients with higher TR fractions showed worse primary outcomes and renal outcomes than those with lower TR fractions. In Cox regression analysis, a 10% increase in TR fraction was significantly associated with primary outcome [hazard ratio (HR) 1.49, 95% confidence interval (CI) 1.29-1.73, P < 0.001] and renal outcome (HR 1.31, 95% CI 1.12-1.55, P = 0.001). TR fraction exhibited a strong positive linear relationship with primary outcomes and renal outcomes in restricted cubic spline curves.

CONCLUSION

CMR-quantified measures of TR were independently associated with adverse clinical outcomes in patients with HFrEF.

Advances in Imaging for Tricuspid Transcatheter Edge-to-Edge Repair: Lessons Learned and Future Perspectives

Severe tricuspid valve (TV) regurgitation (TR) has been associated with adverse long-term outcomes in several natural history studies, but isolated TV surgery presents high mortality and morbidity rates. Transcatheter tricuspid valve interventions (TTVI) therefore represent a promising field and may currently be considered in patients with severe secondary TR that have a prohibitive surgical risk. Tricuspid transcatheter edge-to-edge repair (T-TEER) represents one of the most frequently used TTVI options. Accurate imaging of the tricuspid valve (TV) apparatus is crucial for T-TEER preprocedural planning, in order to select the right candidates, and is also fundamental for intraprocedural guidance and post-procedural follow-up. Although transesophageal echocardiography represents the main imaging modality, we describe the utility and additional value of other imaging modalities such as cardiac CT and MRI, intracardiac echocardiography, fluoroscopy, and fusion imaging to assist T-TEER. Developments in the field of 3D printing, computational models, and artificial intelligence hold great promise in improving the assessment and management of patients with valvular heart disease.

Prevalence and determinants of tricuspid regurgitation after repair of tetralogy of Fallot

BACKGROUND

The prevalence and determinants of tricuspid regurgitation (TR) in patients with repaired Tetralogy of Fallot (rTOF) remain incompletely understood.

OBJECTIVES

To explore the prevalence of and factors associated with TR in patients with rTOF, specifically, the relationship of right ventricular (RV) dilatation with TR severity.

METHODS

Patients (≥17 yrs) with rTOF referred to our service (2000-2019) were identified. Those with severe pulmonary stenosis, significant shunt, or previous tricuspid valve surgery were excluded. Using standard cardiac MRI protocols, RV, right atrial (RA) and tricuspid valve (TV) parameters were measured and compared.

RESULTS

68 consecutively eligible patients with rTOF were included in the study (27 ± 9 yrs., 35% female). Despite substantial RV volume overload (mean RVEDVi 153 mL/m²), the majority of the cohort (78%) had no or only mild TR. RA volumes, tenting height/area and annular diameter were normal (4.9 ± 2.0 mm, 1.1 ± 1.0 cm² and 32.4 ± 6.2 mm, respectively). There was no significant correlation of TR fraction with RVEDVi (r = 0.13; p = 0.30), RVEF (r = 0.09; p = 0.44) or tricuspid annular diameter (r = 0.07; p = 0.62). Only RAVi showed a weak but significant correlation with TR fraction (0.29; p = 0.03). In a pooled cohort analysis, including both rTOF patients and adults with a dilated RV from pre-tricuspid shunt lesions, only rTOF was independently associated with higher TR fraction (p = 0.017).

CONCLUSION

Despite substantial RV dilatation in a cohort with rTOF, there was surprisingly little TR. We found poor correlation between RVEDVi, RA volumes, tricuspid annular dilatation and the presence of significant TR. These findings question commonly held notions regarding the pathophysiology of functional TR in these patients.

New therapeutic approach for tricuspid regurgitation: Transcatheter tricuspid valve replacement or repair

The tricuspid valve is a complex structure with normal function dependent on the leaflet morphology, right atrial and annular dynamics, and right ventricular and chordal support. Thus, the pathophysiology of tricuspid regurgitation (TR) is equally complex and current medical and surgical management options are limited. Transcatheter devices are currently being investigated as possible treatment options with lower morbidity and mortality than open surgical procedures. These devices can be divided by their implant location/mechanism of action: leaflet approximation devices, annuloplasty devices, orthotopic valve implants, and heterotopic valve implants. The current review will discuss each class of transcatheter device therapy, and further delve into the current understanding of who and when to treat. Finally, we will include a brief discussion of the future of device and surgical therapy trials for TR and the remaining questions to answer about this complex disease process.

Imaging and haemodynamic parameters associated with clinical outcomes following isolated tricuspid valve surgery

INTRODUCTION

Isolated tricuspid valve surgery (TVS) may be associated with high morbidity and mortality. The aim of this study was to investigate the association of preoperative imaging and haemodynamic data derived from echocardiography (ECHO), cardiac magnetic resonance (CMR) and right heart catheterisation (RHC) with postoperative outcomes following TVS.

METHODS

In a retrospective cohort study, patients who underwent isolated TVS at our institution between 2012 and 2020 were screened and followed up to 1 year. We only included those who had all three tests before surgery: ECHO, CMR and RHC. Patients with congenital heart disease, infective endocarditis and those who underwent concomitant valve or pericardial surgery were excluded. The primary outcome was a composite of mortality and congestive heart failure at 1 year. Time-to-event analyses at 1 year and Cox proportional hazards regression analyses were performed.

RESULTS

A total of 60 patients were included (mean age of 60±14 years, 63% women), of whom 67% underwent TV repair. The primary outcome occurred in 16 patients (27%) with a 1-year mortality of 7%. It was associated with ECHO-derived right ventricular (RV) free wall strain and RHC-derived RV systolic and diastolic as well as mean pulmonary pressures. On multivariable Cox regression analysis, only RV systolic and diastolic pressures were significantly associated with the primary outcome at 1 year (HRs=5.9 and 3.4, respectively, p<0.05).

CONCLUSION

Baseline invasive haemodynamic assessment could have a strong association with clinical outcomes and help risk-stratify patients undergoing isolated TVS.

Tricuspid Regurgitation Impact on Outcomes (TRIO): A Simple Clinical Risk Score

OBJECTIVE

To determine which clinical variables infer the highest risk for mortality in patients with notable tricuspid regurgitation (TR) and to develop a clinical assessment tool (the Tricuspid Regurgitation Impact on Outcomes [TRIO] score).

PATIENTS AND METHODS

A single-center retrospective cohort of 13,608 patients with undifferentiated moderate to severe TR at the time of index echocardiography between January 1, 2005, and December 31, 2016, was included. Baseline demographic and clinical data were obtained. Patients were randomly assigned to a training (N=10,205) and a validation (N=3403) cohort. Median follow-up was 6.5 years (interquartile range, 0.8 to 11.0 years). Variables associated with mortality were identified by Cox proportional hazards methods. A geographically distinct cohort of 7138 patients was used for further validation. The primary end point was all-cause mortality over 10 years.

RESULTS

The 5-year probability of death was 53% for moderate TR, 63% for moderate-severe TR (hazard ratio [HR], 1.24 [95% CI, 1.17 to 1.31]; P<.001 vs moderate), and 71% for severe TR (HR, 1.55 [95% CI, 1.47 to 1.64]; P<.001 vs moderate). Factors associated with all-cause mortality on multivariate analysis included age 70 years or older, male sex, creatinine level greater than 2 mg/dL, congestive heart failure, chronic lung disease, aspartate aminotransferase level of 40 U/L or greater, heart rate of 90 beats/min or greater, and severe TR. Variables were assigned 1 or 2 points (HR, >1.5) and added to compute the TRIO score. The score was associated with all-cause mortality (C statistic = 0.67) and was able to separate patients into risk categories. Findings were similar in the second, independent and geographically distinct cohort.

CONCLUSION

The TRIO score is a simple clinical tool for risk assessment in patients with notable TR. Future prospective studies to validate its use are warranted.

Role of Cardiovascular Magnetic Resonance in Native Valvular Regurgitation: A Comprehensive Review of Protocols, Grading of Severity, and Prediction of Valve Surgery

Valvular regurgitation is common in developed countries with an increasing prevalence due to the aging of the population and more accurate diagnostic imaging methods. Echocardiography is the gold standard method for the assessment of the severity of valvular heart regurgitation. Nonetheless, cardiovascular magnetic resonance (CMR) has emerged as an additional tool for assessing mainly the severity of aortic and mitral valve regurgitation in the setting of indeterminate findings by echocardiography. Moreover, CMR is a valuable imaging modality to assess ventricular volume and flow, which are useful in the calculation of regurgitant volume and regurgitant fraction of mitral valve regurgitation, aortic valve regurgitation, tricuspid valve regurgitation, and pulmonary valve regurgitation. Notwithstanding this, reference values and optimal thresholds to determine the severity and prognosis of valvular heart regurgitation have been studied lesser by CMR than by echocardiography. Hence, further larger studies are warranted to validate the potential prognostic relevance of the severity of valvular heart regurgitation determined by CMR. The present review describes, analyzes, and discusses the use of CMR to determine the severity of valvular heart regurgitation in clinical practice.

Multi-modality imaging assessment of native valvular regurgitation: an EACVI and ESC council of valvular heart disease position paper

Valvular regurgitation represents an important cause of cardiovascular morbidity and mortality. Imaging is pivotal in the evaluation of native valve regurgitation and echocardiography is the primary imaging modality for this purpose. The imaging assessment of valvular regurgitation should integrate quantification of the regurgitation, assessment of the valve anatomy and function, and the consequences of valvular disease on cardiac chambers. In clinical practice, the management of patients with valvular regurgitation largely relies on the results of imaging. It is crucial to provide standards that aim at establishing a baseline list of measurements to be performed when assessing native valve regurgitation. The present document aims to present clinical guidance for the multi-modality imaging assessment of native valvular regurgitation.

Right ventricular volume and its relationship to functional tricuspid regurgitation

Background

Significant right ventricular (RV) dilatation has long been considered integral to the pathogenesis of functional tricuspid regurgitation (FTR).

Objectives

To explore the relationship of RV dilatation and FTR in patients with ‘pure’ RV volume overload.

Methods

Patients (>17yrs) with RV dilatation due to pre-tricuspid shunts (atrial septal defect; ASD and/or partial anomalous pulmonary venous drainage; PAPVD) referred to our service (2000–2019) were retrospectively identified. Those with pulmonary hypertension, primum ASD or left-heart disease were excluded. Using standard cardiac MRI protocols, RV, right atrial and TV parameters were measured and compared.

Results

Of 52 consecutively eligible patients (42 ± 15yrs, 25 males), 25 had ASDs, 13 had PAPVD and 14 had both conditions. All were in sinus rhythm and none had pulmonary regurgitation. Left and right ventricular ejection fractions were normal (LVEF 63 ± 8%, RVEF 56 ± 8%). Indexed RV end-diastolic volumes (RVEDVi) were moderately increased (males 148 ± 33 mL/m² and females 141 ± 42 mL/m², range 95–267 mL/m²). Despite substantial RV volume overload, no patients had severe tricuspid regurgitation (TR). Only two had > mild TR. There was a weak correlation between tricuspid annular diameter and both degree of RV dilatation (r = 0.37; p = 0.01) and degree of TR (r = 0.38; p = 0.006). There was a similarly poor correlation between right atrial dimensions and the degree of TR (r = 0.34; p = 0.02).

Conclusion

When RV dilatation is simply due to volume overload, we find that significant TR is extremely rare. This gives an important and novel insight; that RV dilatation per se does not result in FTR.

Effect of Tricuspid Valve Repair or Replacement on Survival in Patients With Isolated Severe Tricuspid Regurgitation

Controversies remain in the management strategy for isolated tricuspid regurgitation (TR) because of adverse prognosis and uncertainties regarding the benefits of tricuspid valve surgery. We compared the characteristics and outcomes of a large cohort of patients with isolated TR, based on downstream tricuspid valve surgery versus medical management. Consecutive patients with isolated TR graded at least moderate-to-severe by echocardiography identified between January 2004 and December 2018 (n = 9,031, age 70 ± 15 years, 60% women) were retrospectively studied. The primary end point was time to all-cause mortality during follow-up. Outcomes were compared by management strategy using unadjusted and adjusted survival and multivariable regression analyses. Tricuspid valve surgery was performed in 632 of 9,031 of the cohort (7%), including 514 valve repairs and 118 valve replacements, with in-hospital mortality in 19 patients (2.9%). Overall, there were 3,985 all-cause deaths (44%) over mean follow-up of 2.6 ± 3.3 years. Tricuspid valve surgery was independently associated with lower mortality rate during follow-up, with hazard ratios (HRs) of 0.53 (95% confidence interval [CI] 0.45 to 0.64), and the association persisted in both primary and secondary TR subgroups. Tricuspid valve surgery also had a significantly higher rate of infective endocarditis and heart failure hospitalizations rates during follow-up, at HRs of 5.55 (95% CI 4.00 to 7.71) and 1.29 (95% CI 1.16 to 1.43), respectively. In conclusion, tricuspid valve surgery is rarely performed in isolated TR, but it is independently associated with greater survival for the overall cohort and both primary and secondary etiology subgroups. Increasing the utilization of this surgery at specialized centers is encouraged to try to improve the clinical outcomes for this challenging clinical entity.

Contemporary Etiologies, Outcomes, and Novel Risk Score for Isolated Tricuspid Regurgitation

OBJECTIVES

The authors report etiologies and outcomes and devise a risk model in a large contemporary cohort of patients with isolated tricuspid regurgitation (TR).

BACKGROUND

Isolated TR is a challenging clinical entity with heterogeneous etiology and often poor outcomes, with a paucity of recent research regarding the epidemiology of isolated TR.

METHODS

Consecutive patients with isolated TR graded at least moderate to severe on echocardiography from January 2004 to December 2018 (n = 9,045, mean age 70.4 ± 15.4 years, 60.3% women) were studied. TR etiologies were individually adjudicated as secondary or primary, with subcategories. All-cause death during follow-up was the primary endpoint, with associations between etiology and outcomes analyzed and a risk model created.

RESULTS

Primary and secondary TR etiologies were present in 470 (5.2%) and 8,575 (94.8%) patients, respectively. The main secondary etiologies were left heart disease in 4,664 (54.4%), atrial functional in 2,086 (24.3%), and pulmonary disease in 1,454 (17.0%), and the main primary etiologies were endocarditis in 222 (47.2%), degenerative or prolapse in 86 (18.3%), and prosthetic valve failure in 79 (16.8%). There were 3,987 deaths (44.0%) over a mean follow-up period of 2.6 ± 3.3 years. In unadjusted analyses, patients with secondary TR had worse survival than those with primary TR (HR: 1.56; 95% CI: 1.32-1.85), but this result was not statistically significant in multivariable analysis. The authors devised and internally validated a risk score for predicting 1-year mortality in these patients.

CONCLUSIONS

Secondary TR constituted 95% of isolated significant TR and conferred worse survival than primary TR in unadjusted but not adjusted analyses. The present novel risk score stratifies the risk for 1-year death and may influence decision making for management in these high-risk patients.

Right ventricle dysfunction assessment for transcatheter tricuspid valve repair: A matter of debate

Newer approaches in transcatheter tricuspid valve replacement (TTVR) have recently showed optimistic data of efficacy and safety in patients at high risk for surgery. However, the absence of residual regurgitation (and subsequently higher likelihood for developing afterload mismatch) with TTVR compared with transcatheter tricuspid valve intervention may become a critical concern if RV dysfunction is misdiagnosed. Indeed, such sudden increase in afterload on the right ventricle (RV) may not be tolerable, resulting in higher risk of acute right heart failure in the early postoperative period. In this context, strain imaging may find a further application to provide a more comprehensive stratification of the severity of RV dysfunction and thus help to better define the eligibility criteria and timing for TTVR. Meanwhile, it is of paramount importance to underline the contribution given by the Trivalve study on the understanding of the role of RV function in TTVI, that so far was largely undefined, being evaluated only in small noncontrolled cohorts.

Assessment of the tricuspid valve using cardiovascular magnetic resonance

PURPOSE OF REVIEW

The rapid search for suitable tricuspid transcatheter devices has ignited renewed enthusiasm in accurate characterization of tricuspid valve disease. Cardiovascular magnetic resonance (CMR), traditionally used as the gold standard in assessment for right ventricular size and function, has recently seen its use expanded to assess both the structure and function of the tricuspid apparatus. This review will highlight the role of CMR in tricuspid valve disease and compare it with other commonly used imaging modalities.

RECENT FINDINGS

Dynamic anatomical assessment of the tricuspid apparatus, in combination with accurate leaflet identification, is possible with CMR. Tricuspid regurgitation volume and fraction are derived through an indirect volumetric method, and therefore, able to overcome many traditional hurdles involved with valve regurgitation quantitation. Adverse right heart prognostic factors in tricuspid valve disease, such as right heart volumes, function, and tissue characterization, are optimally assessed using CMR.

SUMMARY

Cardiovascular magnetic resonance is a powerful modality that should be harnessed in order to obtain a multifaceted assessment of tricuspid valve structure, function, and the effects of valve disease on right heart remodeling.

Survival of Tricuspid Valve Replacement in Patients With Previous Tricuspid Valve Surgery

OBJECTIVES

This study was performed to investigate the short-term and long-term survival of patients who underwent reoperative tricuspid valve replacement (TVR).

METHODS

A retrospective analysis was performed of 273 patients who underwent TVRs while hospitalised in Beijing Anzhen Hospital from November 1993 to August 2018. Fifty-six (56) of them underwent reoperative TVR: 36 had previous tricuspid valve repair and 20 had previous TVR. Follow-up was 100% complete, with a mean follow-up of 8 years (range, 1-15 years).

RESULTS

The overall in-hospital mortality was 17.9% (n=10). In the univariate analysis, the overall in-hospital mortality and renal failure rate in the replacement group were lower than those in the repair group (5.0% vs 25%; p=0.046 and 27.8% vs 5%; p=0.040). However, in-hospital mortality was no longer statistically significant after multivariate adjustment (adjusted OR, 0.318; 95% CI, 0.030-3.338; p=0.340). There was no significant difference in survival between the patients with previous repair and those with previous replacement (log-rank test, p=0.839). Factors that correlated with long-term mortality on multivariate analysis were age >60 years (adjusted HR, 11.753; 95% CI, 1.686-81.915; p=0.013); cardiopulmonary bypass time (adjusted HR, 1.019; 95% CI, 1.005-1.034; p=0.009); intensive care unit time (adjusted HR, 1.024; 95% CI, 1.006-1.042; p=0.009); and ventilation time (adjusted HR, 0.982; 95% CI, 0.965-0.998; p=0.030).

CONCLUSIONS

Reoperative TVR was associated with high in-hospital mortality and morbidity. Overall in-hospital mortality was similar between the previous replacement group and the previous repair group. Previous tricuspid valve repair and replacement had similar long-term survival.

Impact of right ventricular systolic function in patients with significant tricuspid regurgitation. A cardiac magnetic resonance study

BACKGROUND

Right ventricle (RV) dilatation and dysfunction are established criteria for intervention in severe tricuspid regurgitation (TR); however thresholds to support intervention are lacking. New measures of RV function such as RV shortening (RVS) and effective RV ejection fraction (eRVEF) may be earlier markers of RV dysfunction.

PURPOSE

to compare the prognostic impact of different parameters of RV function and to describe cut-off values of RV size/function and TR severity of poor prognosis.

METHODS

Consecutive patients evaluated in the Heart Valve Clinic with significant TR (severe, massive or torrential TR) undergoing a CMR study were included. In addition to parameters of biventricular volume and function, RVS and eRVEF were assessed. A combined endpoint of hospital admission due to right heart failure and cardiovascular mortality was defined.

RESULTS

75 patients were included (age 75 ± 8 years, female 75%). During a median follow-up of 3 years (IQR: 1.4-3.9 years), 39% experienced the endpoint. Cut-off values of worse prognosis were: RVS ≥ -14%, eRVEF ≤34%, RVEF ≤58%, RV-EDV ≥100 ml/m2, TR regurgitant fraction (TRF) ≥40% and TR volume ≥ 42 ml. RVS and eRVEF identified higher rates of RV dysfunction than RVEF. After adjustment for age and LVEF, both eRVEF ≤34% (HR: 5.29 [2.25-12.4]) and RVS ≥ -14% (HR: 3.46 [1.13-9.17]) were significantly associated with outcomes. Among all parameters of RV function, eRVEF was the strongest predictor of outcomes, incremental to RVEF (ΔC-statistic 0.139 [0.040-0.237], p = 0.005). Patients with eRVEF ≤34% and RV-EDV ≥100 ml/m2 or eRVEF ≤34% and TRF ≥40% had the worst prognosis (p < 0.01 for both).

CONCLUSION

RVS and eRVEF identify higher rates of RV dysfunction beyond RVEF. Among all measures, eRVEF held the strongest association with outcomes, incremental to RVEF.

Contemporary review in the multi-modality imaging evaluation and management of tricuspid regurgitation

The tricuspid valve has gained interest recently because of the poor outcomes with current treatments and advances in percutaneous valve interventions. A sound understanding of the anatomy and pathologies of the tricuspid valve is critical in its evaluation and management of tricuspid regurgitation (TR). A multi-modality imaging approach with transthoracic echocardiography, transesophageal echocardiography, computed tomography, magnetic resonance imaging all have their individual and collective roles in the evaluation of TR and guidance of surgical and percutaneous procedures. This combined with clinical factors will contribute to defining timing, indications, modality selection and risk stratification for tricuspid valve interventions, which currently remains controversial.

Prognostic Implication of Right Ventricle Parameters Measured on Preoperative Cardiac MRI in Patients with Functional Tricuspid Regurgitation

OBJECTIVE

To investigate the prognostic value of preoperative cardiac magnetic resonance imaging (MRI) for long-term major adverse cardiac and cerebrovascular events (MACCEs) in patients undergoing tricuspid valve (TV) surgery for functional tricuspid regurgitation (TR).

MATERIALS AND METHODS

The preoperative cardiac MR images, New York Heart Association functional class, comorbidities, and clinical events of 78 patients (median [interquartile range], 59 [51-66.3] years, 28.2% male) who underwent TV surgery for functional TR were comprehensively reviewed. Cox proportional hazards analyses were performed to assess the associations of clinical and imaging parameters with MACCEs and all-cause mortality.

RESULTS

For the median follow-up duration of 5.4 years (interquartile range, 1.2-6.6), MACCEs and all-cause mortality were 51.3% and 23.1%, respectively. The right ventricular (RV) end-systolic volume index (ESVI) and the systolic RV mass index (RVMI) were higher in patients with MACCEs than those without them (77 vs. 68 mL/m², p = 0.048; 23.5 vs. 18.0%, p = 0.011, respectively). A high RV ESVI was associated with all-cause mortality (hazard ratio [HR] per value of 10 higher ESVI = 1.10, p = 0.03). A high RVMI was also associated with all-cause mortality (HR per increase of 5 mL/m² RVMI = 1.75, p < 0.001). After adjusting for age and sex, only RVMI remained a significant predictor of MACCEs and all-cause mortality (p < 0.05 for both). After adjusting for multiple clinical variables, RVMI remained significantly associated with all-cause mortality (p = 0.005).

CONCLUSION

RVMI measured on preoperative cardiac MRI was an independent predictor of long-term outcomes in patients who underwent TV surgery for functional TR.

Preoperative Right Ventricular Free-Wall Longitudinal Strain as a Prognosticator in Isolated Surgery for Severe Functional Tricuspid Regurgitation

Background Severe tricuspid regurgitation (TR) should be intervened before the development of irreversible right ventricular (RV) dysfunction. However, current guidelines do not provide criterion related to RV systolic function to guide optimal surgical timing. We investigated the prognostic value of RV longitudinal strain in patients undergoing isolated surgery for severe functional TR. Methods and Results We enrolled 115 consecutive patients (aged 62±10 years; 23.5% men; 62.6% [n=72] with previous left-sided valve surgery) who underwent isolated surgery for severe functional TR at 2 tertiary centers. Preoperative clinical and echocardiographic parameters, including RV free-wall longitudinal strain (RVFWSL), were collected. The primary end point was a composite of cardiac death and unplanned readmission attributable to cardiovascular causes 5 years after surgery. Forty patients (34.8%) reached the primary end point during 333 person-years of follow-up. There were 11 cardiac deaths and 34 unplanned readmissions attributable to cardiovascular causes, with 5 patients experiencing both. An absolute preoperative RVFWSL <24% was associated with the primary end point (hazard ratio, 2.30; 95% CI, 1.22-4.36; P=0.011), independent of clinical risk factors, including European System for Cardiac Operative Risk Evaluation II and hemoglobin levels. Meanwhile, other conventional echocardiographic measures of RV systolic function were not significant. The addition of an absolute RVFWSL <24% provided incremental prognostic value to the clinical model for predicting the primary end point. Conclusions Preoperative RVFWSL as an indicator of RV dysfunction was an independent prognosticator in patients undergoing isolated surgery for severe functional TR. Thus, preoperative RVFWSL could help determine the optimal surgical timing for severe functional TR.

Unmasking pulmonary hypertension following tricuspid valve replacement

In this Viewpoint, we highlight a possible hemodynamic problem arising following tricuspid valve replacement (TVR) in patients with severe chronic tricuspid regurgitation, represented by "unmasking" of pulmonary hypertension (PH) following the surgery. We share an observation that should alert cardiologists to the fact that this increasingly utilized surgery is not risk free, and careful assessment of the right ventricular function and pulmonary circulation preoperatively is extremely important, especially in patients with preexisting risk factors for PH, since TVR may lead to a sudden increase in right ventricular afterload.

Multimodality Imaging of the Tricuspid Valve and Right Heart Anatomy

The characterization of tricuspid valve and right-heart anatomy has been gaining significant interest in the setting of new percutaneous transcatheter interventions for tricuspid regurgitation. Multimodality cardiac imaging provides a wealth of information about the anatomy and function of the tricuspid valve apparatus, right ventricle, and right atrium, which is pivotal for diagnosis and prognosis and for planning of percutaneous interventions. The present review describes the role of echocardiography, cardiac magnetic resonance, and multidetector row cardiac computed tomography for right heart and tricuspid valve assessment.

Postoperative persistent diastolic dyssynchronous expansion in patients with Ebstein's anomaly

In Ebstein’s anomaly, maximal expansion in the atrialized right ventricle (RV) occurs during early diastole, whereas that of the functional RV occurs in late diastole, resulting in diastolic dyssynchronous expansion (DSE). We quantitatively assessed DSE and identified preoperative factors correlated with persistent DSE after surgery. Seventeen patients diagnosed with Ebstein’s anomaly in whom transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) images available were retrospectively analyzed for quantitative DSE assessment and 10 patients who underwent surgery and postoperative TTE available were additionally analyzed for postoperative DSE. Severity of DSE was assessed by the time difference of maximal expansion between the atrialized and functional RV divided by the cardiac cycle length × 100 (“DSE index”). Relations between DSE and, clinical, electrophysiologic parameters and the severity of tricuspid valve (TV) tethering (the RV length / tethering height during diastole: “Tethering index”) were assessed. In total patients, median DSE index and tethering index were 30.3 and 2.1 respectively, and the DSE index was correlated with tethering index (r_s = 0.664, P = 0.004). In 10 patients who underwent surgery, this association remained after surgery and at 2-year follow up. Tethering index ≥2.5 separated patients with and without persistent DSE. In conclusion, DSE exists in Ebstein’s anomaly. DSE index is related to the tethering index and DSE persists postoperatively if tethering index ≥ 2.5. As the persistent DSE might possibly impede the optimal recovery of RV function after surgery, severity of TV tethering should take into account in considering surgery.

Tricuspid annular diameter and right ventricular volume on preoperative cardiac CT can predict postoperative right ventricular dysfunction in patients who undergo tricuspid valve surgery

BACKGROUND

We investigated the predictive value of preoperative computed tomography (CT)-derived tricuspid annular and right ventricular (RV) parameters for postoperative RV dysfunction in patients undergoing tricuspid valve (TV) surgery.

METHODS

We retrospectively reviewed clinical, transthoracic echocardiography (TTE), and CT data of 100 consecutive patients who underwent cardiac CT and subsequently received TV surgery. Preoperative cardiac CT and TTE parameters were analyzed, including TV annulus diameter and RV size. Univariate and multivariate logistic regression analyses were performed to identify significant predictors for postoperative RV dysfunction, both in the entire study population and in the subgroup of patients without preoperative RV dysfunction.

RESULTS

Postoperative RV dysfunction occurred in 46% of all patients. In the multivariate logistic regression analysis, longer TV annulus diameter (>29.3 mm/m² on four-chamber view; (odds ratio [OR] 3.56, 95% confidence interval [CI] 1.13-11.24), larger RV volume (RV end-diastolic volume/body surface area > 128.8 ml/m²) on CT (OR 3.85, 95% CI 1.24-11.98) and presence of preoperative RV dysfunction on TTE (OR 11.96, 95% CI 2.8-50.99) were independent predictors for postoperative RV dysfunction in the entire study population (P < 0.05). Among patients without preoperative RV dysfunction, longer TV annulus diameter (OR 4.02, 95% CI 1.20-13.41) and larger RV volume on CT (OR 6.09, 95% CI 1.87-19.80) were independent predictors for postoperative RV dysfunction (P < 0.05).

CONCLUSIONS

Preoperative assessment of cardiac CT imaging-based TV annular diameter and RV volume can provide independent information for predicting postoperative RV dysfunction in patients undergoing TV surgery.

Multi-Modality Imaging in the Evaluation and Treatment of Tricuspid Regurgitation

PURPOSE OF REVIEW

The goal of this review is to cover the epidemiology of tricuspid regurgitation (TR), anatomy of the tricuspid valve (TV), and the mechanisms and modern treatment of TR. The focus will be on the role of echocardiography, cardiac CT, and MRI to determine the mechanism, severity, and management strategies of TR.

RECENT FINDINGS

The evaluation and management of TR is a rapidly growing field with significant advances in both imaging and interventions. Important advances have been made to understand TV anatomy and physiology in 3D echo, CT, and MRI. Additional understanding of the abnormal outcomes in both primary TR and secondary TR have been appreciated. Multiple transcatheter devices have reached the stage of early trials in high surgical risk cohorts with favorable initial findings. TR is a significant cardiovascular problem and vastly undertreated in the present era. There has been tremendous growth in knowledge of mechanisms of TR, its prognostic implications, timing of intervention, and development of novel treatment strategies. Multimodality imaging plays a key role in evaluation and treatment of this condition.

Multimodality Imaging of the Tricuspid Valve for Assessment and Guidance of Transcatheter Repair

The tricuspid valve is a highly complex structure, with variability in the number of leaflets and scallops. The mechanism of regurgitation is multifactorial in etiology, a mix of functional and degenerative tricuspid regurgitation. Iatrogenic tricuspid regurgitation is becoming more common secondary to pacemaker wire impingement of leaflet function and coaptation. Echocardiographic imaging of the tricuspid valve is particularly challenging given its anatomic location and other interfering structures, including pacemaker wires. Preprocedural planning and intraprocedural guidance for transcatheter intervention relies on a comprehensive understanding of tricuspid anatomy and the use of 3-dimensional transesophageal echocardiography. The incorporation of computed tomography and cardiac magnetic resonance imaging likely will provide increasing accuracy and optimization of procedural success.

Cardiac Computed Tomography and Magnetic Resonance Imaging in the Evaluation of Mitral and Tricuspid Valve Disease

Transcatheter interventions to treat mitral and tricuspid valve disease are becoming increasingly available because of the growing number of elderly patients with significant comorbidities or high operative risk. Thorough clinical and imaging evaluation in these patients is essential. The latter involves both characterization of the mechanism and severity of valvular disease as well as determining the hemodynamic consequences and extent of ventricular remodeling, which is an important predictor of future outcomes. Moreover, an assessment of the suitability and risk of complications associated with device-specific therapies is also an important component of the preprocedural evaluation in this cohort. Although echocardiography including 2-dimensional and 3-dimensional methods has an important role in the initial assessment and procedural guidance, cross-sectional imaging, including both computed tomographic imagning and cardiac magnetic resonance imaging, is increasingly being integrated into the evaluation of mitral and tricuspid valve disease. In this review, we discuss the role of cross-sectional imaging in mitral and tricuspid valve disease, primarily valvular regurgitation assessment, with an emphasis on the preprocedural evaluation and implications for transcatheter interventions.

Effects of slice orientation on reproducibility of sequential assessment of right ventricular volumes and ejection fraction: short-axis vs transverse SSFP cine cardiovascular magnetic resonance

BACKGROUND

Test-retest reproducibility is of utmost importance in follow-up of right ventricular (RV) volumes and function; optimal slice orientation though is not yet known. We compared test-retest reproducibility and intra-/inter-observer variability of right ventricular (RV) volumes and function assessed with short-axis and transverse cardiovascular magnetic resonance (CMR).

METHODS

Eighteen volunteers underwent cine CMR for RV assessment obtaining ventricular coverage in short-axis and transverse slice orientation. Additional 2D phase contrast flow imaging of the main pulmonary artery (MPA) was performed. After complete repositioning repeat acquisitions were performed. Data sets were contoured by two blinded observers. Statistical analysis included Student's t-test, Bland-Altman plots, intra-class correlation coefficient (ICC) and 2-way ANOVA, SEM and minimal detectable difference calculations.

RESULTS

Heart rates (65.0 ± 7.4 vs. 67.6 ± 9.9 bpm; P = 0.1) and MPA flow (89.8 ± 16.6 vs. 87.2 ± 14.9 mL; P = 0.1) did not differ between imaging sessions. EDV and ESV demonstrated an inter-study bias of 0.4 %[-9.5 %,10.3 %] and 2.1 %[-12.3 %,16.4 %] for short-axis and 1.1 %[-7.3 %,9.4 %] and 0.8 %[-16.0 %,17.6 %] for transverse orientation, respectively. There was no significant interaction between imaging orientation and interstudy reproducibility (p = 0.395-0.824), intra-observer variability (p = 0.726-0.862) or inter-observer variability (p = 0.447-0.706) by 2-way ANOVA. Inter-observer agreement by ICC was greater for short axis versus transverse orientation for all parameters (0.769-0.986 vs. 0.625-0.983, respectively). Minimal detectable differences for short axis and transverse orientations were 10.1 mL/11.5 mL for EDV, 8.3 mL/8.4 mL for ESV and 4.1 % vs. 4.7 % for EF, respectively.

CONCLUSION

Short-axis and transverse orientation both provide reliable and reproducible measures for follow-up of RV volumes and global function. Therefore, additional transverse SSFP cine CMR may not necessarily be required if performed for the sole purpose of quantitative volumetric RV assessment.