Geometric Determinants of Functional Tricuspid Regurgitation

3D transoesophageal echocardiographic assessment of acute reverse remodelling of the tricuspid annulus after transcatheter edge-to-edge repair

AIMS

Our study aims to evaluate the acute remodelling of the tricuspid valve annulus immediately after the tricuspid transcatheter edge-to-edge repair (T-TEER) by using intraprocedural transoesophageal 3D echocardiography.

METHODS AND RESULTS

We prospectively enrolled 62 consecutive symptomatic patients with at least severe tricuspid regurgitation (TR), who underwent T-TEER with the TriClip System between March 2021 and June 2024. The following parameters were assessed using a multiplanar reconstruction analysis performed off-line using a 3D data set: septal-lateral (SL) and antero-posterior (AP) annulus diameters; annulus area; annulus perimeter; and eccentricity index. The acute procedural success was achieved in 85.5%. We observed an acute reduction in SL (from a median of 43 to 38 mm, P < 0.0001), AP (from a median of 46 to 45 mm, P < 0.0001), area (from a median of 17.9 to 15.95 cm2, P < 0.0001), perimeter (from a median of 145.5 to 137 mm, P < 0.0001), and eccentricity index (from 0.92 to 0.87, P < 0.0001). The tricuspid valve (TV) annulus was progressively larger in patients with higher residual TR. Analysis of the subgroups according to procedural success showed an acute inverse remodelling of the TV annulus independent of the acute procedural success.

CONCLUSION

The TV geometry necessitates the use of 3D echocardiography for accurate assessment of annular remodelling post T-TEER. The reduction in TR grade and TV annulus dimensions begins immediately after TriClip implantation. Concurrently, the baseline TV geometry influences the procedural results.

The Use of 3D-Echo in Edge-to-Edge Percutaneous Tricuspid Valve Repair

The tricuspid valve (TV) is a complex anatomical entity. As surgical treatment for isolated tricuspid regurgitation has traditionally been associated with high peri- and post-operative mortality, advances in percutaneous transcatheter techniques of repair and replacement of the TV are emerging as safe and effective alternatives. This review summarizes the current evidence on the use of three-dimensional echocardiography to assist transcatheter-edge-to-edge repair (TEER) in patients with tricuspid regurgitation.

Predictive value of CT-based and AI-reconstructed 3D-TAPSE in patients undergoing transcatheter tricuspid valve repair

Background

The tricuspid annular plane systolic excursion (TAPSE) assessed by echocardiography has failed in predicting outcomes in patients with severe tricuspid regurgitation (TR) undergoing transcatheter tricuspid valve intervention (TTVI). Considering the complex shape of the tricuspid annulus and right ventricle, as well as the difficult echocardiographic image acquisition of the right heart, cardiac computed tomography (CT) might be superior for the analysis of the annular excursion. Thus, this study aimed to analyze whether CT-captured TAPSE provides additional value in predicting outcomes after TTVI.

Methods and results

For TTVI procedure planning, 75 patients (mean age, 77 ± 8 years; 61% female) with severe TR underwent full cardiac cycle CT. Septal, lateral, anterior, and posterior TAPSE, as well as TAPSE- volume, were analyzed. Indexed anterior and posterior (iTAPSE) and TAPSE volume were reduced in patients with right ventricular ejection fraction <45%. At 1 year after TTVI (mean follow-up, 193 ± 146days), the combined endpoint of death and rehospitalization occurred in significantly fewer patients with posterior iTAPSE >4.5 mm/m2 (17.2% vs. 63.6%; HR 0.225, CI 0.087-0.581; P < 0.001) and in patients with iTAPSE volume >9 ml/m2 (16.4% vs. 57.1%; HR: 0.269 CI 0.105-0.686; P = 0.003). Echocardiographic TAPSE correlated best with lateral CT-based TAPSE, although both failed in predicting outcomes after TTVI. In multivariate Cox regression, posterior iTAPSE was found to be a significant predictor of outcome 1 year after TTVI.

Conclusions

Posterior iTAPSE is an independent predictor of cardiovascular outcomes among patients undergoing TTVI. Furthermore, CT-measured TAPSE has incremental value and refines risk stratification for clinical outcomes in patients undergoing TTVI.

Comprehensive Dynamic 3-Dimensional Analysis of the Tricuspid Valve in Functional Tricuspid Regurgitation: Implications for Prophylactic Tricuspid Valve Intervention

OBJECTIVES

To track and measure changes in the tricuspid annulus (TA) using 3-dimensional (3D) echocardiography during a complete cardiac cycle in patients with functional tricuspid regurgitation (TR) compared to patients without TR, and to compare tricuspid annular plane systolic excursion (TAPSE) derived from 2-dimensional (2D) and 3D coordinates as a measure of right ventricular (RV) function to the standard method of 2D fractional area change (FAC).

DESIGN

Intraoperative 3D echocardiography data were collected prospectively, followed by postprocessing software analysis to track and reconstruct changes throughout the cardiac cycle.

SETTING

Data were collected from 108 patients undergoing left-sided heart surgery at 2 large academic centers-Beth Israel Deaconess Medical Center in Boston, MA and Rhode Island Hospital, Providence, RI-between November 2018 and April 2020.

PARTICIPANTS

The final dataset (n = 92) included 2 groups: the no significant functional TR (NTR) group (n = 74), defined as ≤ mild TR and TA <35 mm, and the significant functional TR (FTR) group (n = 18), defined as ≥ moderate TR.

INTERVENTIONS

3D TEE datasets were analyzed, and the motion of TA coordinates was tracked during complete cardiac cycle in 2D and 3D planes using postprocessing and software analysis. Computational modeling of TA motion was performed using computer-aided design. In further analysis, reconstructed and 3D printed models of TV were developed for the 2 groups.

MEASUREMENTS AND MAIN RESULTS

`Patients in FTR group had larger TA size during the cardiac cycle, with less overall excursion and reduced annular dynamism. The 3D motion of TA for lateral, anterolateral, and posterolateral coordinates was lower in the FTR group compared to the NTR group [18 ± 6.8 vs 13.6 ± 8.5( p = 0.02); 15.2 ± 5.5 vs 11.3 ± 6.0 (p = 0.009); and 17.6 ± 6.6 vs 12.3 ± 5.2 (p = 0.002), respectively]. TAPSE derived from 3D planes was more accurate for RV function assessment when comapred with 2D FAC (area under the curve [AUC], 0.704; p = 0.011) than 2D TAPSE (AUC, 0.625; p = 0.129). Finally, in the FTR group, the anteroseptal-posterolateral diameter was consistently larger during all phases of the cardiac cycle compared to the conventionally measured septolateral diameter.

CONCLUSIONS

3D echocardiographic assessment of TA helps better understand its geometry and dynamism in functional TR and is more accurate than 2D measurements for RV function assessment.

Atrial Functional Tricuspid Regurgitation: A Comprehensive Review of Pathophysiology, Diagnosis, and Management Strategies

Atrial fibrillation (AF), the most prevalent sustained cardiac arrhythmia, is intricately linked with atrial functional tricuspid regurgitation (AFTR), a condition distinguished from ventricular functional tricuspid regurgitation by its unique pathophysiological mechanisms and clinical implications. This review article delves into the multifaceted aspects of AFTR, exploring its epidemiology, pathophysiology, diagnostic evaluation, and management strategies. Further, we elucidate the mechanisms underlying AFTR, including tricuspid annular dilatation, right atrial enlargement, and dysfunction, which collectively contribute to the development of tricuspid regurgitation in the absence of significant pulmonary hypertension or left-sided heart disease. The section on diagnostic evaluation highlights the pivotal role of echocardiography, supplemented by cardiac magnetic resonance (CMR) imaging and computed tomography (CT), in assessing disease severity and guiding treatment decisions. Management strategies for AFTR are explored, ranging from medical therapy and rhythm control to surgical and percutaneous interventions, underscoring the importance of a tailored, multidisciplinary approach. Furthermore, the article identifies gaps in current knowledge and proposes future research directions to enhance our understanding and management of AFTR. By providing a comprehensive overview of AFTR, this review aims to raise awareness among healthcare professionals and stimulate further research to improve patient care and outcomes in this increasingly recognized condition.

Tricuspid valve and right-heart chamber remodelling in elderly subjects with secondary tricuspid regurgitation

BACKGROUND

The prevalence of secondary tricuspid regurgitation (TR) increases with ageing, but the exact mechanisms and the pattern of tricuspid valve (TV) remodelling are yet to be defined. This knowledge is needed to guide patient selection for the evolving therapeutic options. We sought to explore the prevalence and predictors of secondary TR in the elderly, as well as the associated pattern of right-heart chamber and TV remodelling.

METHODS

Consecutive older subjects (60-year-old or older) were prospectively enrolled and detailed analysis of right-heart chambers and TV was conducted (ClinicalTrials.gov ID: NCT05784883). TR severity was defined based on a multiparametric approach.

RESULTS

Out of 213 patients (age, 67.1 ± 5.9 years, 52.6% female), 48.8% had mild and 15.5% had moderate-severe TR. The frequency of moderate-severe TR increased from 4.5% in those without to 32.9% in those with underlying abnormalities of the left/right heart. There was a significant trend of worsening right-heart chamber and TV remodelling across the three grades of TR severity (none-trace, mild, and moderate-severe; p-value for linear trend < 0.001). ROC curve-defined cut-points of TV remodelling parameters predicting moderate-severe TR were annular dilatation ≥3.75 cm (AUC: 0.74), tenting area ≥1.45 cm2 (AUC: 0.67), and leaflet length ≥2.25 cm (AUC: 0.61) with increasing frequency of moderate-severe TR from 7.2% through 64.7%, in those with none vs. all three criteria (p < 0.001). The most important correlate of the three TV remodelling parameters was right ventricular and atrial (RV and RA) dilatation.

CONCLUSION

Rather than ageing per se, the presence of underlying cardiac abnormalities determines the frequency of moderate-severe TR. Progressive remodelling of right-heart chambers and TV geometry starts with the development of mild TR. TA dilatation, increased tenting, and leaflet elongation are three important correlates of the development of TR that parallel progressive RV and RA dilatation.Study Registration: ClinicalTrials.gov ID: NCT05784883.

Tricuspid Anterior and Posterior Patch (TRAPP) Repair of Functional Tricuspid Regurgitation

OBJECTIVE

Annuloplasty is the most common strategy for repair of functional tricuspid regurgitation (FTR) but is not effective in patients with massive/torrential FTR or leaflet tethering. To address the deficits of tricuspid annuloplasty, TRicuspid Anterior and Posterior Patch (TRAPP) repair was developed, which is a pericardial patch augmentation of the anterior and posterior leaflets.

METHODS

To test this repair, a previously validated ex vivo model in an explanted porcine heart was used, wherein annular and leaflet geometry were evaluated using a 3-dimensional structured light scanner at 4 time points: (1) baseline, (2) induction of FTR, (3) annuloplasty repair, and (4) patch repair.

RESULTS

Compared with the regurgitant tricuspid valve, annuloplasty reduced annular circumference (13.7 to 9.5 cm) and area (13.7 vs 6.1 cm2), whereas TRAPP repair did not alter annular dimensions (circumference: 13.7 vs 13.5 cm; area: 13.7 vs 13.6 cm2). Annuloplasty increased leaflet tenting angles (anterior: 53.5° vs 41.0°; posterior: 59.7° vs 48.2°; septal: 38.9° vs 31.4°) whereas TRAPP repair relieved anterior and posterior leaflet tenting (anterior: 28.9° vs 41.0°; posterior: 34.9° vs 48.2°; septal: 33.2° vs 31.4°) and restored geometry comparable to the native tricuspid valve. Central coaptation lengths were greater with TRAPP repair than with annuloplasty for all 3 leaflets (anterior: 12.7 vs 9.5 mm; posterior: 12.2 vs 8.2 mm; septal: 7.4 vs 4.6 mm).

CONCLUSIONS

Compared with annuloplasty, TRAPP repair yielded greater coaptation length, resolved leaflet tethering, and resulted in a larger annular area that may facilitate durable repair of advanced FTR, which previously would have required replacement.

Transcatheter Repair of Tricuspid Valve Regurgitation: A Systematic Review

Introduction: Clinically significant severe tricuspid regurgitation (TR) is a common untreated pathology associated with increased mortality. Even though surgical valve replacement has been the mainstay option, transcatheter intervention is a novel and potentially effective tool. To the best of our knowledge, this is the first systematic review that assessed and compared clinical and echocardiographic outcomes of coaptation and annuloplasty devices in patients with clinically significant TR. Methods: PubMed, the Cochrane Central Register of Controlled Trials, and EMBASE were searched for articles published from August 2016 until February 2023. Primary endpoints were technical and procedural successes. Secondary endpoints were TR grade, NYHA, change in 6 min walk distance (6MWD), and echocardiographic parameters at 30-day follow-up. Results: We included thirty-eight studies consisting of 2273 patients with severe symptomatic TR (NYHA III-IV 77% and severe/massive/torrential TR 83.3%) and high surgical risk (mean EUROSCORE of 7.54). The technical success for the annuloplasty devices was 96.7% and for the coaptation device was 94.8%. The procedural success for the annuloplasty devices was 64.6% and for the coaptation device was 81.4%. The 6MWD increased by 17 m for the coaptation devices and increased by 44 m after 30 days for the annuloplasty devices. A reduction in TR grade to <2 was seen in 70% of patients with coaptation and 59% of patients with annuloplasty devices. Conclusions: Transcatheter tricuspid valve intervention appears to be feasible and is associated with favorable outcomes.

Key Imaging Factors for Transcatheter Management of Tricuspid Regurgitation: Device and Patient Selection

The growing awareness of tricuspid regurgitation (TR) and the fast-expanding array of devices aiming to percutaneously repair or replace the tricuspid valve have underscored the central role of multi-modality imaging in comprehensively assessing the anatomical and functional characteristics of TR. Accurate phenotyping of TR, the right heart, and pulmonary vasculature via echocardiography, computed tomography, and, occasionally, cardiovascular magnetic resonance and right heart catheterization is deemed crucial in choosing the most suitable treatment strategy for each patient and achieving procedural success. In the first part of the present review, key imaging factors for patient selection will be discussed. In the ensuing sections, an overview of the most commonly used, commercially available systems for transcatheter repair/replacement will be presented, along with their respective selection criteria and information on intraprocedural imaging guidance; these are edge-to-edge repair, orthotopic and heterotopic replacement, and valve-in-valve procedures.

Sex-Specific Insights into Etiology, Diagnosis, Treatment, and Prognosis in Significant Tricuspid Regurgitation: A Narrative Review

In recent decades, a burgeoning interest in tricuspid regurgitation (TR) has been prompted by a heightened awareness of its prevalence and the advent of dedicated percutaneous treatment approaches. Despite considerable understanding of its intricate anatomy and response to varying pressure and loading conditions, the impact of biological sex remains a subject of investigation. While TR typically afflicts more women, significant differences in TR etiology and post-treatment outcomes have not been conclusively established. This narrative review seeks to consolidate the latest evidence concerning sex-related nuances in anatomy, pathophysiology, diagnosis, treatment, and prognosis of significant tricuspid regurgitation. Through synthesizing this information, we aim to provide a comprehensive understanding of how sex may influence the management and prognosis of this condition.

New Therapeutic Advances in the Management of Tricuspid Valve Regurgitation

Tricuspid regurgitation (TR) is an intricate disorder that has a negative outlook, while surgical treatment is linked to increased mortality. Primary TR occurs due to a structural defect in the tricuspid valve (TV), while secondary TR is a more prevalent condition often associated with pulmonary hypertension, heart failure, and atrial fibrillation. The use of specific surgical procedures to improve TR is limited in everyday clinical practice due to the heightened surgical risk and delayed patient presentation. The development of other transcatheter heart valve procedures has led to a significant increase in transcatheter TV operations, which can be attributed to certain technological advancements. This review aims to provide an updated overview of transcatheter TV procedures, available alternative therapies, and standards for patient selection. It will also highlight the current state of development in this field, which is characterized by rapid progress and numerous ongoing clinical trials.

Mid-term outcomes of tricuspid annuloplasty using the Tri-Ad Adams tricuspid annuloplasty ring

OBJECTIVES

The Tri-Ad Adams tricuspid annuloplasty ring is a recent innovative prosthesis characterized by a semi-rigid central component and fully flexible extremities. The goal of this study was to assess the short-term and mid-term results following implantation of the Tri-Ad Adams ring.

METHODS

A retrospective analysis was conducted on patients who underwent tricuspid annuloplasty using the Tri-Ad Adams ring between August 2016 and October 2021.

RESULTS

Our study enrolled a total of 248 participants. The median age was 64.0 (interquartile range: 56.0-71.5) years. The median EuroSCORE II was 4.3% (2.7-7.5%), with 37 patients (14.9%) having a history of cardiac operations. Tricuspid regurgitation of grade 2-3 was observed in 63.7% of cases, and the median tricuspid annular diameter was 3.3 (2.8-3.6) cm. Concurrent procedures included mitral valve replacement (n = 160, 64.5%), mitral valve repair (n = 75, 30.2%), aortic valve replacement (n = 72, 29.0%) and the maze procedure (n = 170, 68.5%). Immediate postoperative tricuspid regurgitation≥moderate was present in 1 patient (0.4%). Early death occurred in 14 patients (5.6%). Major complications included low cardiac output syndrome (n = 18, 0.3%), acute kidney injury (n = 14, 5.6%) and permanent pacemaker placement (n = 15, 6.0%). According to the Kaplan-Meier analysis, the 4-year rates of freedom from overall mortality and moderate-to-severe tricuspid regurgitation were 96.9% and 91.6%, respectively. There were no incidents of tricuspid valve reoperations, ring detachment or significant tricuspid stenosis (trans-tricuspid valve gradient ≥ 5 mmHg).

CONCLUSIONS

Tricuspid annuloplasty utilizing the Tri-Ad Adams ring demonstrated favourable outcomes in both the early and midterm periods. Further studies are warranted to confirm the long-term results.

A comprehensive overview of surgical and transcatheter therapies to treat tricuspid regurgitation in patients with heart failure

PURPOSE OF REVIEW

The unique pathophysiologic considerations of severe tricuspid regurgitation (TR) have led to advancements in surgical and transcatheter treatments. The purpose of this review is to highlight the current surgical and transcatheter tricuspid valve interventions (TTVI) to functional TR.

RECENT FINDINGS

Surgical repair with ring annuloplasty consistently demonstrates better outcomes than surgical replacement or other repair approaches. However, surgical uptake of TR correction remains relatively low, and operative mortality rates are still high owing to multiple comorbidities and advanced tricuspid valve disease/right ventricular dysfunction at time of referral. Pivotal trials for tricuspid transcatheter edge-to-edge repair (T-TEER) and transcatheter TV replacement (TTVR) indicate improved quality of life compared to medical therapy alone for high-surgical-risk patients with severe symptomatic TR. Trials are underway to assess caval valve implantation (CAVI), which holds hope for many severe TR patients who are not ideal candidates for T-TEER or orthotopic TTVR. Peri-procedural optimization of right ventricular function remains critical to promote both device success and patient outcomes.

SUMMARY

Clinical outcomes after surgical TV intervention are poor, often due to intervening late in the disease course of TR. TTVI covers a treatment gap for patients deemed inoperable or high-surgical-risk, but earlier referral for TV interventions is still important prior to patients developing multiorgan dysfunction from chronic untreated TR.

Device therapy for patients with atrial fibrillation and heart failure with preserved ejection fraction

Device therapy is a nonpharmacological approach that presents a crucial advancement for managing patients with atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF). This review investigated the impact of device-based interventions and emphasized their potential for optimizing treatment for this complex patient demographic. Cardiac resynchronization therapy, augmented by atrioventricular node ablation with His-bundle pacing or left bundle-branch pacing, is effective for enhancing cardiac function and establishing atrioventricular synchrony. Cardiac contractility modulation and vagus nerve stimulation represent novel strategies for increasing myocardial contractility and adjusting the autonomic balance. Left ventricular expanders have demonstrated short-term benefits in HFpEF patients but require more investigation for long-term effectiveness and safety, especially in patients with AF. Research gaps regarding complications arising from left ventricular expander implantation need to be addressed. Device-based therapies for heart valve diseases, such as transcatheter aortic valve replacement and transcatheter edge-to-edge repair, show promise for patients with AF and HFpEF, particularly those with mitral or tricuspid regurgitation. Clinical evaluations show that these device therapies lessen AF occurrence, improve exercise tolerance, and boost left ventricular diastolic function. However, additional studies are required to perfect patient selection criteria and ascertain the long-term effectiveness and safety of these interventions. Our review underscores the significant potential of device therapy for improving the outcomes and quality of life for patients with AF and HFpEF.

Transthoracic and transoesophageal echocardiography for tricuspid transcatheter edge-to-edge repair: a step-by-step protocol

Tricuspid regurgitation (TR) carries an unfavourable prognosis and often leads to progressive right ventricular (RV) failure. Secondary TR accounts for over 90% of cases and is caused by RV and/or tricuspid annulus dilation, in the setting of left heart disease or pulmonary hypertension. Surgical treatment for isolated TR entails a high operative risk and is seldom performed. Recently, transcatheter edge-to-edge repair (TEER) has emerged as a low-risk alternative treatment in selected patients. Although the experience gained from mitral TEER has paved the way for the technique's adaptation to the tricuspid valve (TV), its anatomical complexity necessitates precise imaging. To this end, a comprehensive protocol integrating 2D and 3D imaging from both transthoracic echocardiography (TTE) and transoesophageal echocardiography (TOE) plays a crucial role. TTE allows for an initial morphological assessment of the TV, quantification of TR severity, evaluation of biventricular function, and non-invasive haemodynamic evaluation of pulmonary circulation. TOE, conversely, provides a detailed evaluation of TV morphology, enabling precise assessment of TR mechanism and severity, and represents the primary method for determining eligibility for TEER. Once a patient is considered eligible for TEER, TOE, alongside fluoroscopy, will guide the procedure in the catheterization lab. High-quality TOE imaging is crucial for patient selection and to achieve procedural success. The present review examines the roles of TTE and TOE in managing patients with severe TR eligible for TEER, proposing the step-by-step protocol successfully adopted in our centre.

Computed tomographic analysis of the morphometrics and dynamics of the tricuspid annulus in secondary functional tricuspid regurgitation

Objectives

Secondary functional tricuspid regurgitation (FTR) management remains controversial mainly due to the lack of knowledge in its pathogenesis and the difficulties to measure the actual dimensions of tricuspid annulus (TA) with current imaging methods. Using a novel method based on multiphase cardiac computed tomography (CT) scan acquisition to accurately analyze the right atrioventricular junction size, we sought to explore modifications of TA morphometry and dynamics in secondary FTR.

Methods

Echocardiographic and cardiac CT studies were obtained from 21 patients with severe mitral regurgitation (MR group) and 21 patients with dilated cardiomyopathy (DCMP group). Using an in-house software, a 3-dimensiontal (3D) semiautomated delineation of the TA perimeter was assessed. Modifications of diameters, 2-dimensional/3D areas and perimeters were analyzed through time. These 2 groups of patients were compared with 30 healthy subjects, considering the presence of a significant (≥2+) versus nonsignificant (<2+) FTR in each group.

Results

Maximum TA 3D areas were 7.0 ± 1.2 cm2/m2 in healthy subjects at mid-to-late diastole and were smaller than in the MR group (9.8 ± 2.1 cm2/m2, P < .001) and the DCMP group (9.2 ± 3.0 cm2/m2, P < .001). In the MR group, patients with FTR <2+ had also larger TA areas and diameters than healthy patients (P < .01 for all 3D/2-dimensional parameters). TA shape was more circular only in the DCMP group with FTR ≥2+ compared with other patients (P < .05 for eccentricity). In multivariate analysis, both RA area (P < .001) and RV volume (P = .002) were independently related to TA dilatation.

Conclusions

Based on multiphase CT image analyses, TA dilatation was directly related to RV and RA enlargement. Patients with severe mitral myxomatous disease and nondysfunctional tricuspid valve had yet dilated TA, which questioned the current cut-off recommendation for concomitant tricuspid annuloplasty in this specific population.

Papillary muscle approximation in chronic ovine functional tricuspid regurgitation

OBJECTIVE

Isolated tricuspid ring annuloplasty remains the surgical standard for functional tricuspid regurgitation repair but offers suboptimal results when right ventricular dilation and remodeling along with papillary muscle displacement is present. Addressing subvalvular remodeling with papillary muscle approximation may improve clinical outcomes.

METHODS

Functional tricuspid regurgitation and biventricular dysfunction were induced in 8 healthy sheep by rapid ventricular pacing (200-240 bpm) for 27 ± 6 days. Subsequently, animals underwent cardiopulmonary bypass for implantation of sonomicrometry crystals on the tricuspid annulus, right ventricle, and papillary muscle tips. Papillary approximation sutures were anchored between anterior-posterior and anterior-septal papillary muscles and externalized through right ventricular free wall to epicardial tourniquets. After weaning from cardiopulmonary bypass, sequential papillary muscle approximations were performed. Simultaneous hemodynamic, sonomicrometry, and echocardiographic data were collected at baseline and after each papillary muscle approximation.

RESULTS

With rapid pacing, right ventricular fractional area change decreased from 59 ± 6% to 38 ± 8% (P < .001), whereas tricuspid annulus diameter increased from 2.4 ± 0.3 cm to 3.3 ± 0.6 cm (P = .003). Tricuspid regurgitation (0-4+) increased from +0 ± 0 to +3.3 ± 0.7 (P < .001). Both anterior-posterior and anterior-septal papillary muscle approximation significantly reduced functional tricuspid regurgitation from +3.3 ± 0.7 to +2 ± 0.5 and +1.9 ± 0.6, respectively (P < .001). Reduction of tricuspid insufficiency with both subvalvular interventions was associated with decreased distance of the anterior papillary muscle to the annular centroid.

CONCLUSIONS

Papillary muscle approximations were effective in reducing severe ovine functional tricuspid regurgitation associated with right ventricular dilation and papillary muscle displacement. Further studies are needed to evaluate efficacy of this adjunct to ring annuloplasty in repair of severe functional tricuspid regurgitation.

Reverse remodeling of the tricuspid valve complex by sinus rhythm restoration after catheter ablation

BACKGROUND

Atrial fibrillation (AF) can cause right atrium enlargement and structural changes of the tricuspid valve annulus (TVA). The features of the structural changes and benefits obtained from rhythm-control therapy is unknown.

OBJECTIVES

We investigated how the TVA changes and whether its size decreases after rhythm-control therapy.

METHODS

Multi-detector row computed tomography (MDCT) was performed before and after catheter ablation for AF. TVA morphology and right atrium (RA) volume was evaluated by MDCT. The features of TVA morphology in patients with AF after rhythm-control therapy were analyzed.

RESULTS

MDCT was performed in 89 patients with AF. The 3D perimeter was more correlated with diameter in the anteroseptal-posterolateral (AS-PL) direction than in the anterior-posterior direction. Seventy patients showed 3D perimeter reduction owing to rhythm-control therapy and the change was associated with the rate of change in the AS-PL diameter. Rate of change of the 3D perimeter was associated with that of the AS-PL diameter among TVA morphology and RA volume. We divided the subjects into three groups according to the tertiles of the TA perimeter. 3D perimeter in all groups was decreased after rhythm-control therapy. The AS-PL diameter in the 2nd and 3rd tertiles was decreased and increased TVA height in all groups.

CONCLUSION

TVA in patients with AF was enlarged and flattened in the early phase, and rhythm-control therapy resulted in reverse remodeling of the TVA and in the reduction of right atrial volume. These results suggest that early AF intervention can lead to the restoration of the TVA structure.

Multidetector CT-derived tricuspid annulus measurements predict tricuspid regurgitation reduction after transcatheter aortic valve replacement

AIM

To use multidetector row computed tomography (MDCT)-derived tricuspid annulus (TA) measurements to identify predictors for tricuspid regurgitation (TR) reduction after transcatheter aortic valve replacement (TAVR), and to investigate the impact of TR change on prognosis.

MATERIALS AND METHODS

A retrospective, single-centre study was conducted on consecutive patients who underwent TAVR with concomitant baseline mild or more severe TR from April 2012 to April 2022. TA parameters were measured using MDCT.

RESULTS

The study comprised 266 patients (mean age 74.2 ± 7.6 years, 147 men) and 45.1% had more than one grade of TR reduction at follow-up. Independent predictors of TR reduction at follow-up were distance between TA centroid and antero-septal commissure (odd ratio [OR] 0.776; 95% confidence interval [CI]: 0.672-0.896, p=0.001), baseline TR of moderate or worse (OR 4.599; 95% CI: 2.193-9.648, p<0.001), systolic pulmonary artery pressure (OR 1.018; 95% CI: 1.002-1.035, p=0.027), age (OR 0.955; 95% CI: 0.920-0.993, p=0.019), and pre-existing atrial fibrillation (OR 0.209; 95% CI: 0.101-0.433, p<0.001). Patients without TR reduction had higher rates of rehospitalisation (hazard ratio [HR] 0.642; 95% CI: 0.413-0.998, p=0.049).

CONCLUSIONS

The MDCT-derived TA parameter was predictive of TR reduction after TAVR. Persistent TR after TAVR was associated with higher rates of rehospitalisation.

Three-dimensional analysis of the tricuspid annular geometry in healthy subjects and in patients with different grades of functional tricuspid regurgitation

BACKGROUND

Accurate sizing of the tricuspid valve annulus is essential for determining the optimal timing of tricuspid valve (TV) intervention. Two-dimensional (2D) echocardiography has limitations for comprehensive TV analysis. Three-dimensional (3D) imaging of the valve provides a better understanding of its spatial anatomy and enables more accurate measurements of TV structures.

OBJECTIVES

The study aimed to analyze tricuspid annulus (TA) parameters in normal heart and in different grades of functional tricuspid regurgitation (TR); to compare TA measurements obtained by 2D and 3D echocardiography.

METHODS

One hundred fifty-five patients (median age 65 years, 57% women) with normal TV and different functional TR grades underwent 2D and 3D transthoracic echocardiography. The severity of TR was estimated using multiparametric assessment according to the guidelines. Mid-systolic 3D TA parameters were calculated using TV dedicated software. The conventional 2D systolic TA measurements in a standard four-chamber view were performed.

RESULTS

In mid-systole, the normal TA area was 9.2 ± 2.0 cm2 for men and 7.4 ± 1.6 cm2 for women. When indexed to body surface area (BSA), there were no significant differences in the 3D parameters between genders. The 2D TA diameters were smaller than those measured in 3D. The ROC curve analysis identified that all 3D TA parameters can accurately differentiate between different functional TR grades. Additionally, the optimal cut-off values were identified for each TA parameter.

CONCLUSIONS

Gender, body size, and age have an impact on the TA parameters in healthy subjects. 2D measurements are smaller than 3D parameters. The reference values for 3D metrics according to TR severity can help in identifying TA dilation and distinguishing between different functional TR grades.

Tricuspid annular and right atrial volume changes are associated in healthy adults-insights from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study

Introduction

The tricuspid valve and its annulus (TA) and the right atrium (RA) play a significant role in regulating blood flow in the right heart. However, their effect on each other is not fully understood even in normal circumstances. Three-dimensional (3D) speckle-tracking echocardiography (3DSTE) is able to simultaneously assess TA and RA at the same time in a non-invasive way. The present study aimed to examine associations between tricuspid annular (TA) dimensions and right atrial (RA) volumes in healthy adults by 3DSTE.

Methods

The present study comprised 144 healthy subjects (mean age: 34.4 ± 12.6 years, 72 males), who participated in this study on a voluntary basis for screening between 2011 and 2015. In all subjects, electrocardiography, two-dimensional Doppler echocardiography and 3DSTE have been performed.

Results

With increasing end-systolic maximum RA volume, all end-systolic and end-diastolic TA dimensions showed simultaneous increase, but in various degrees resulting in (non-significant) reduction of TA functional properties. Similarly, with increasing diastolic pre-atrial contraction and minimum RA volumes, TA dimensions increased simultaneously (except end-diastolic TA diameter), but in various degrees resulting in reduced TA fractional shortening and fractional area change. With increasing RA dimensions, end-systolic and end-diastolic TA dimensions showed simultaneous increase, but in different, sometimes not significant degrees. While RA stroke volumes showed increasing pattern with TA dilation, RA emptying fractions have not changed substantially.

Conclusions

3DSTE is suitable for non-invasive assessment of TA dimensions and RA volumes at the same time using the same 3D echocardiographic dataset. Significant associations between TA size and RA volumes exist in healthy circumstances. Strong associations in case of dilation of TA in the presence of higher RA volumes could partly explain functional tricuspid regurgitation later developing in subjects in sinus rhythm.

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 annular dynamics, not diameter, predicts tricuspid regurgitation after mitral valve surgery: Results from a prospective randomized trial

Objective

Current guidelines advise using prophylactic tricuspid valve annuloplasty during mitral valve surgery, especially in the presence of annular diameter enlargement. However, several retrospective studies and a prospective randomized study from our department could not confirm that diameter enlargement is predictive of late regurgitation. We examined whether 2- and 3-dimensional echocardiographic and clinical characteristics could identify patients who will develop moderate or severe recurrent tricuspid regurgitation.

Methods

Patients with less than severe functional tricuspid regurgitation (FTR) were randomized not to receive tricuspid annuloplasty, and 11 of 53 of them were excluded from the study because 3-dimensional echocardiographic analysis was not possible. Cox regression was used to estimate the model-based probability of moderate or severe FTR (vena contracta ≥3 mm) or progression of TR and FTR regression using valve dimensions (annulus area, diameter perimeter, nonplanar angle, and sphericity index), dynamics (annulus contraction, annulus displacement, and displacement velocity), and clinical parameters as possible predictors.

Results

At a median follow-up of 3.8 years (range, 3-5.6 years), 17 patients had moderate or severe FTR or progression, and 13 had FTR regression. Our models identified annular displacement velocity as a significant predictor for FTR recurrence and nonplanar angle as a significant predictor for FTR regression.

Conclusions

Annular dynamics, not the dimension, predict recurrence and regression of FTR. Annular contraction should be systematically investigated as a possible surrogate of right ventricle function to prophylactically treat the tricuspid valve.

Cellular and Molecular Mechanisms Underlying Tricuspid Valve Development and Disease

Tricuspid valve (TV) disease is highly prevalent in the general population. For ages considered "the forgotten valve" because of the predominant interest in left-side valve disease, the TV has now received significant attention in recent years, with significant improvement both in diagnosis and in management of tricuspid disease. TV is characterized by complex anatomy, physiology, and pathophysiology, in which the right ventricle plays a fundamental role. Comprehensive knowledge of molecular and cellular mechanisms underlying TV development, TV disease, and tricuspid regurgitation-related right-ventricle cardiomyopathy is necessary to enhance TV disease understanding to improve the ability to risk stratify TR patients, while also predicting valve dysfunction and/or response to tricuspid regurgitation treatment. Scientific efforts are still needed to eventually decipher the complete picture describing the etiopathogenesis of TV and TV-associated cardiomyopathy, and future advances to this aim may be achieved by combining emerging diagnostic imaging modalities with molecular and cellular studies. Overall, basic science studies could help to streamline a new coherent hypothesis underlying both the development of TV during embryogenesis and TV-associated disease and its complications in adult life, providing the conceptual basis for the ultimate and innovative field of valve repair and regeneration using tissue-engineered heart valves.

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.

Mild Tricuspid Regurgitation: A Marker of Disease Burden Independently Associated with Increased Mortality

INTRODUCTION

Tricuspid regurgitation (TR) is a common finding which appears to be associated with a worse prognosis. There are conflicting data regarding the prognostic impact of mild TR. We examined the clinical characteristics and echocardiographic properties of subjects with TR and its impact on clinical outcome with particular emphasis on subjects with mild TR.

METHODS

Consecutive echocardiography examinations during 5 years were evaluated for TR severity and outcome including mortality and cardiovascular hospitalizations.

RESULTS

The study included 21,429 subjects; 45% of the subjects had mild TR, 15% had moderate TR, and 6.5% had severe TR. Primary organic TR was evident in 7% of the subjects, a percentage that increased with increasing TR severity. TR severity was incrementally associated with older subjects with an increasing number of comorbidities and echocardiographic abnormalities. 29% of the subjects died at a median follow-up duration of 8.7 years. Increasing severity of TR was independently and incrementally associated with mortality. Subjects with mild TR had a 25% increased mortality rate compared to subjects with minimal TR (HR 1.25, 95% CI: 1.12-1.39, p < 0.001) after adjustment for significant clinical parameters. TR severity was also an independent incrementally graded predictor of cardiovascular hospitalization and mortality (mild TR: HR 1.23, 95% CI: 1.12-1.34, p < 0.001).

CONCLUSIONS

TR is associated with older and sicker patients with numerous comorbidities. TR severity is a predictor of a worse clinical outcome. Mild TR was independently associated with decreased survival. TR should be considered a marker of a disease burden with a poor prognosis.

Three-dimensional echocardiography of the tricuspid valve

Due to the proportionally high mortality rates associated with isolated tricuspid valve surgery, the invasive treatment of such pathology, historically, has been left largely unaddressed. Recently, there has been an appreciation for the mortality and morbidity of tricuspid valve disease, giving rise to the movement towards identifying less invasive, transcatheter approaches for treatment. Due to the technical complexity of these procedures along with the uniqueness and variability of tricuspid valve anatomy, a better appreciation of the tricuspid valve anatomy and pathology is required for pre-procedural planning. While two-dimensional echocardiography serves as the initial non-invasive modality for tricuspid valve evaluation, three-dimensional echocardiography provides a complete en face view of the tricuspid valve and surrounding structures, as well contributes further information regarding disease etiology and severity. In this review, we discuss the utility of three-dimensional echocardiography as a supplement to two-dimensional imaging to better assess tricuspid valve disease and anatomy to aide in future innovative therapies.

Tricuspid Valve Geometrical Changes in Patients with Functional Tricuspid Regurgitation: Insights from a CT Scan Analysis Focusing on Commissures

BACKGROUND

Cardiac computed tomography (CT) provides important insights into the geometrical configuration of the tricuspid valve (TV). The purpose of the present study was to assess the geometrical changes of TV in patients with functional tricuspid regurgitation (TR) using novel CT scan parameters and to correlate these findings with echocardiography.

METHODS

This single-center study enrolled 86 patients undergoing cardiac CT and divided them into two groups according to the presence or not of severe TR (43 patients with TR ≥ 3+ and 43 controls). The measurements collected were as follows: TV annulus area and perimeter, septal-lateral and antero-posterior annulus diameters, eccentricity, distance between commissures, segment between the geometrical centroid and commissures, and the angles of commissures.

RESULTS

We found a significant correlation between all annulus measurements and the grade of TR, except in regard to angles. TR ≥ 3+ patients had significantly larger TV annulus area and perimeter, larger septal-lateral, and antero-posterior annulus dimensions, as well as larger commissural distance and centroid-commissural distance. In patients with TR ≥ 3+ and controls, the eccentricity index predicted a circular shape and an oval shape of the annulus, respectively.

CONCLUSIONS

These novel CT variables focusing on commissures increase the anatomical understanding of the TV apparatus and the TV geometrical changes in patients with severe functional TR.

Dynamic assessment of the tricuspid annulus in a healthy Asian population: A four-dimensional echocardiography study

BACKGROUND

Tricuspid annulus (TA) geometry and function reference values are limited, especially for Asian populations. We aimed to explore TA using four-dimensional echocardiography (4DE) in a healthy Asian population.

METHODS

A total of 355 healthy Asian volunteers (median age 34 years; 52% males) were prospectively enrolled. TA geometry and function were analyzed using 4DE throughout the cardiac cycle.

RESULTS

The TA area, perimeter, and dimensions were smallest at end systole (ES) and largest at late diastole (LD). Normal TA parameters at end diastole (ED) in different sex and age groups were obtained. TA areas, perimeters, and dimensions in males were significantly larger than those in females at ED; BSA-indexed perimeters and BSA-indexed dimensions in males were significantly smaller than those in females at ED. TA parameters correlated well with tricuspid valve (TV) tenting, right ventricle (RV), and right atrium (RA) parameters.

CONCLUSIONS

Reference values of TA parameters were obtained by 4DE in an Asian population. Quantitative data on TA geometry and function are essential for TA pathology and therapeutics.

Incidence of atrial functional tricuspid regurgitation and its correlation with tricuspid valvular deformation in patients with persistent atrial fibrillation

Background

With the growing prevalence of atrial fibrillation (AF), concomitant atrial functional tricuspid regurgitation (FTR) is increasing. In this study, we aimed to elucidate the incidence of significant atrial FTR and its association with tricuspid valvular (TV) deformation in patients with persistent AF.

Methods

We retrospectively enrolled 344 patients (73.0 ± 9.3 years, 95 female) with persistent AF who underwent 2-dimensional echocardiography. We excluded patients with left-sided heart disease, pulmonary hypertension treated with pulmonary vasodilators, and congenital heart disease. We defined significant TR as having TR ≥ moderate; and tricuspid annulus (TA) diameter, tethering height, and area were measured in all patients.

Results

Among the study population, 80 (23.3%) patients had significant TR. TA diameter, tethering height, and area were significantly greater in the significant TR group (all p < 0.001). In multivariable analysis, TA diameter was independently associated with significant TR (odds ratio 1.1 per mm, p = 0.03), whereas TV tethering height was not. Receiver operating characteristic curve for significant TR exhibited the best predictive value of TA diameter indexed for body surface area [23 mm/m²; area under the curve (AUC) = 0.87] compared with absolute TA diameter (39 mm; AUC = 0.74) and TA diameter indexed for height (0.22 mm/cm; AUC = 0.80).

Conclusion

Approximately 25% of patients with persistent AF had significant TR. The BSA-corrected TA diameter was strongly associated with significant TR, which might be helpful for predicting the development of significant TR and considering its therapeutic strategy in patients with persistent AF.

Force Profiles of Single Ventricle Atrioventricular Leaflets in Response to Annular Dilation and Leaflet Tethering

We sought to understand how leaflet forces change in response to annular dilation and leaflet tethering (LT) in single ventricle physiology. Explanted fetal bovine tricuspid valves were sutured onto image-derived annuli and ventricular mounts. Control valves (CON) were secured to a size-matched hypoplastic left heart syndrome (HLHS)-type annulus and compared to: (1) normal tricuspid valves secured to a size-matched saddle-shaped annulus, (2) HLHS-type annulus with LT, (3) HLHS-type annulus with annular dilation (dilation valves), or (4) a combined disease model with both dilation and tethering (disease valves). The specimens were tested in a systemic heart simulator at various single ventricle physiologies. Leaflet forces were measured using optical strain sensors sutured to each leaflet edge. Average force in the anterior leaflet was 43.2% lower in CON compared to normal tricuspid valves (P < 0.001). LT resulted in a 6.6% increase in average forces on the anterior leaflet (P = 0.04), 10.7% increase on the posterior leaflet (P = 0.03), and 14.1% increase on the septal leaflet (P < 0.001). In dilation valves, average septal leaflet forces increased relative to the CON by 42.2% (P = 0.01). In disease valves, average leaflet forces increased by 54.8% in the anterior leaflet (P < 0.001), 37.6% in the posterior leaflet (P = 0.03), and 79.9% in the septal leaflet (P < 0.001). The anterior leaflet experiences the highest forces in the normal tricuspid annulus under single ventricle physiology conditions. Annular dilation resulted in an increase in forces on the septal leaflet and LT resulted in an increase in forces across all 3 leaflets. Annular dilation and LT combined resulted in the largest increase in leaflet forces across all 3 leaflets.

Real-Time Monitoring and Step-by-Step Guidance for Transcatheter Tricuspid Annuloplasty Using Transesophageal Echocardiography

Transcatheter tricuspid valve intervention (TTVI) is a novel alternative to functional tricuspid regurgitation (FTR) for patients with prohibitive surgical risk. Devices have been designed according to different pathophysiological mechanisms of FTR, including ones to achieve an edge-to-edge repair and others aiming at direct annuloplasty. Recently, a transcatheter tricuspid valve repair system mimicking a surgical Kay procedure (K-Clip™ system, Huihe Medical Technology, Shanghai, China) completed its salvage-use trial. The system, which clips the posterior annulus to achieve bicuspidization of the TV, demonstrated acceptable procedural safety and efficacy. Each TTVI system has distinct characteristics for echocardiographic imaging and special consideration for intraoperative guidance. This review focuses on elaborating how two-dimensional and three-dimensional transesophageal echocardiography (TEE) are used in clinical practice to guide K-Clip™ implantation in comparison to other direct annular reduction devices. A limited number of TEE work planes are proposed for the procedure with the aim to provide a steeper learning curve for the echocardiographer and interventionalist while simplifying the implantation steps.

The evolving role of multi-modality imaging in transcatheter tricuspid valve interventions

Tricuspid valve pathophysiology is not well-understood. Emergence of novel transcatheter tricuspid therapies has fueled the requirements for improved imaging visualization techniques and interventional imaging physician skillsets in guiding these complex transcatheter procedures. There is growing understanding on the clinical significance of tricuspid regurgitation which expanded the interest for percutaneous tricuspid valve interventions. The present review concentrates on three essential aspects of tricuspid valve pathophysiology: anatomical considerations for tricuspid interventions, optimal timing of tricuspid interventions by imaging guidance, and the role of interventional imaging physicians’ skillset and knowledge in this field.

Morphological and Dynamic Analysis of the Right Atrioventricular Junction in Healthy Subjects with 4D Computed Tomography

PURPOSE

To improve knowledge of the tricuspid valve and right atrioventricular junction (RAVJ) coupling, four-dimensional (4D) imaging is mandatory (3D + time). Based on multiphase cardiac-volume computed tomography (CT) and innovative 4D analysis, we proposed to assess dynamical features of tricuspid annulus (TA) in relation to the right ventricle (RV) and right atrial (RA) functions.

METHODS

Cardiac-volume CT data sets through time were obtained in 30 healthy patients (Male 57%, mean age 57 ± 11 years). Using an in-house software, 3D semi-automated delineation of 18 points around TA perimeter were defined through 10 cardiac phases within RR interval and used to calculate TA features such as 3D/2D areas, perimeters, 360°-diameters and vertical deformation. RV and RA inner contours were also delineated. Bi-dimensional parameters were compared with multiplanar reconstruction (MPR) measurements.

RESULTS

TA was elliptical in horizontal projection with a maximal eccentricity index (EcI_max) of 0.58 ± 0.12; and saddle-shaped in vertical projection with a horn nearby the antero-septal commissure. This feature remained throughout the cardiac cycle, but TA was more planar and less circular in late diastole (TA-height: 4.53 ± 1.06 mm, EcI_max = 0.61 ± 0.14) when TA 3D area and perimeter reached a maximum of 7.05 ± 1.23 and 7.48 ± 0.93cm/m², respectively. Correlations between minimal and maximal TA 3D areas and TA Projected 2D areas were excellent (r = 0.993 and r = 0.995, p < 0.001). TA 2D area measurements by MPR overestimated the projected values by 22 to 24%. Correlation between RV concentric strain and TA maximal diameter shortening was r = 0.452 (p = 0.01).

CONCLUSIONS

Cardiac-volume CT improves physiological knowledge of the relationships between the RAVJ components in healthy subjects.

Reference ranges of tricuspid annulus geometry in healthy adults using a dedicated three-dimensional echocardiography software package

Background

Tricuspid annulus (TA) sizing is essential for planning percutaneous or surgical tricuspid procedures. According to current guidelines, TA linear dimension should be assessed using two-dimensional echocardiography (2DE). However, TA is a complex three-dimensional (3D) structure.

Aim

Identify the reference values for TA geometry and dynamics and its physiological determinants using a commercially available three-dimensional echocardiography (3DE) software package dedicated to the tricuspid valve (4D AutoTVQ, GE).

Methods

A total of 254 healthy volunteers (113 men, 47 ± 11 years) were evaluated using 2DE and 3DE. TA 3D area, perimeter, diameters, and sphericity index were assessed at mid-systole, early- and end-diastole. Right atrial (RA) and ventricular (RV) end-diastolic and end-systolic volumes were also measured by 3DE.

Results

The feasibility of the 3DE analysis of TA was 90%. TA 3D area, perimeter, and diameters were largest at end-diastole and smallest at mid-systole. Reference values of TA at end-diastole were 9.6 ± 2.1 cm2 for the area, 11.2 ± 1.2 cm for perimeter, and 38 ± 4 mm, 31 ± 4 mm, 33 ± 4 mm, and 34 ± 5 mm for major, minor, 4-chamber and 2-chamber diameters, respectively. TA end-diastolic sphericity index was 81 ± 11%. All TA parameters were correlated with body surface area (BSA) (r from 0.42 to 0.58, p &lt; 0.001). TA 3D area and 4-chamber diameter were significantly larger in men than in women, independent of BSA (p &lt; 0.0001). There was no significant relationship between TA metrics with age, except for the TA minor diameter (r = −0.17, p &lt; 0.05). When measured by 2DE in 4-chamber (29 ± 5 mm) and RV-focused (30 ± 5 mm) views, both TA diameters resulted significantly smaller than the 4-chamber (33 ± 4 mm; p &lt; 0.0001), and the major TA diameters (38 ± 4 mm; p &lt; 0.0001) measured by 3DE. At multivariable linear regression analysis, RA maximal volume was independently associated with both TA 3D area at mid-systole (R2 = 0.511, p &lt; 0.0001) and end-diastole (R2 = 0.506, p &lt; 0.0001), whereas BSA (R2 = 0.526, p &lt; 0.0001) was associated only to mid-systolic TA 3D area.

Conclusions

Reference values for TA metrics should be sex-specific and indexed to BSA. 2DE underestimates actual 3DE TA dimensions. RA maximum volume was the only independent echocardiographic parameter associated with TA 3D area in healthy subjects.

Functional tricuspid regurgitation, related right heart remodeling, and available treatment options: good news for patients with heart failure?

Significant functional tricuspid regurgitation (FTR) represents a poor prognostic factor independent of right ventricular (RV) function. It is usually the consequence of left-sided cardiac diseases that induce RV dilatation and dysfunction, but it can also resulted from right atrial (RA) enlargement and consequent tricuspid annular dilatation. FTR is very frequent among patients with heart failure, particularly in those with reduced LVEF and concomitant functional mitral regurgitation. The development of three-dimensional echocardiography enabled detailed assessment of tricuspid valve anatomy, subvavlular apparatus, and RA and RV changes, as well as accurate evaluation of FTR etiology. Due to high in-hospital mortality risk in patients who were operatively treated for isolated FTR, it has been treated only medically for a long time. Percutaneous approach considers mainly transcatheter tricuspid valve repair (edge-to-edge and annuloplasty) and represents a very attractive option for the high-risk patients. Studies that investigated the effects of different devices showed excellent feasibility and safety, followed by significant reduction in FTR grade, improvement in functional capacity and NYHA class, quality of life, and reduction in hospitalization due to heart failure. Some investigations also reported a decreased mortality in FTR patients. Nevertheless, the results of these investigations should be interpreted with cautious due to the small number of participants and relatively short follow-up. The aim of this review was to summarize the existing data about the clinical importance of FTR and FTR-induced right heart remodeling and currently existing therapeutic approaches for treatment of FTR.

Transcatheter tricuspid valve intervention techniques and procedural steps for the treatment of tricuspid regurgitation: a review of the literature

Severe tricuspid regurgitation (TR) is an undertreated common pathology associated with significant morbidity and mortality. Classically, surgical repair or valve replacement were the only therapeutic options and are associated with up to 10% postprocedural mortality. Transcatheter tricuspid valve interventions are a novel and effective therapeutic option for the treatment of significant TR. Several devices have been developed with different mechanisms of action. They are classified as annuloplasty devices, replacement devices, caval valve implantation and coaptation devices. In this review, we provide a step-by-step description of the procedural steps and techniques of every device along with video support.

Novel Computed Tomography Variables for Assessing Tricuspid Valve Morphology: Results from the TRIMA (Tricuspid Regurgitation IMAging) Study

BACKGROUND

Computed tomography (CT) is the recommended imaging technique for defining the anatomical suitability for current transcatheter technologies and planning tricuspid valve (TV) intervention. The aim of the Tricuspid Regurgitation IMAging (TRIMA) study was to assess the geometrical characteristics of the TV complex using novel CT parameters.

METHODS

This prospective, single-center study enrolled 22 consecutive patients with severe tricuspid regurgitation, who underwent a cardiac CT study dedicated to the right chambers. The following variables were obtained: annulus area and perimeter, septal-lateral and antero-posterior diameters, tenting height, and anatomical regurgitant orifice area. Moreover, the following novel annular parameters were assessed: distance between commissures, distance between TV centroid and commissures, and angles between centroid and commissures.

RESULTS

A significant phasic variability during the cardiac cycle existed for all variables except for eccentricity, angles, and distance between the postero-septal and antero-posterior commissure and distance between the centroid and antero-posterior commissure. There was a significant relationship between the TV annulus area and novel annular parameters, except for annular angles. Additionally, novel annular variables were found to predict the annulus area.

CONCLUSIONS

These novel additional variables may provide an initial platform from which the complexity of the TV annular morphology can continue to be better understood for further improving transcatheter therapies.

Atrial Functional Tricuspid Regurgitation as a Distinct Pathophysiological and Clinical Entity: No Idiopathic Tricuspid Regurgitation Anymore

Functional tricuspid regurgitation (FTR) is a strong and independent predictor of patient morbidity and mortality if left untreated. The development of transcatheter procedures to either repair or replace the tricuspid valve (TV) has fueled the interest in the pathophysiology, severity assessment, and clinical consequences of FTR. FTR has been considered to be secondary to tricuspid annulus (TA) dilation and leaflet tethering, associated to right ventricular (RV) dilation and/or dysfunction (the "classical", ventricular form of FTR, V-FTR) for a long time. Atrial FTR (A-FTR) has recently emerged as a distinct pathophysiological entity. A-FTR typically occurs in patients with persistent/permanent atrial fibrillation, in whom an imbalance between the TA and leaflet areas results in leaflets malcoaptation, associated with the dilation and loss of the sphincter-like function of the TA, due to right atrium enlargement and dysfunction. According to its distinct pathophysiology, A-FTR poses different needs of clinical management, and the various interventional treatment options will likely have different outcomes than in V-FTR patients. This review aims to provide an insight into the anatomy of the TV, and the distinct pathophysiology of A-FTR, which are key concepts to understanding the objectives of therapy, the choice of transcatheter TV interventions, and to properly use pre-, intra-, and post-procedural imaging.

Surgical Correction of Tricuspid Regurgitation

The tricuspid valve is an often forgotten but relevant cause of significant morbidity and mortality. Serious consideration should be given to addressing the valve in patients undergoing left-sided valve surgery who have functional TR, or an enlarged annulus. Tricuspid repair with a ring annuloplasty has shown improved long-term survival and freedom from recurrent TR at as long as 15 years of follow-up compared to suture annuloplasty or other repairs where a prosthetic ring is not used.

Transcatheter Tricuspid Valve Therapy: From Anatomy to Intervention

Nowadays, severe symptomatic tricuspid regurgitation (TR) affects millions of persons worldwide. However, the benefit of surgical correction of isolated secondary TR remains controversial because of the increased risk of periprocedural mortality and morbidity. In recent years, novel transcatheter tricuspid valve interventions (TTVI) were developed to treat TR, so that TTVI is currently considered in symptomatic, inoperable, anatomically eligible patients. TTVI can be divided into these five domains: edge-to-edge leaflet repair, tricuspid annuloplasty, caval implants, spacer, and total valve replacement. Each transcatheter intervention needs specific imaging protocols for assessing the anatomical feasibility and consequentially predicting the procedural success. This review summarizes the available multimodality imaging tools for screening patients with TR, and identifies anatomical characteristics to choose the best option for the patient.