Tricuspid annulus: A spatial and temporal analysis

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 < 0.001). TA 3D area and 4-chamber diameter were significantly larger in men than in women, independent of BSA (p < 0.0001). There was no significant relationship between TA metrics with age, except for the TA minor diameter (r = −0.17, p < 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 < 0.0001), and the major TA diameters (38 ± 4 mm; p < 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 < 0.0001) and end-diastole (R2 = 0.506, p < 0.0001), whereas BSA (R2 = 0.526, p < 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.

Computationally Assessed 3D Anatomical Proximities and Spatial Relationships Among the Tricuspid Valve Annulus, Right Coronary Artery, and Triangle of Koch: Implications for Transcatheter Tricuspid Annuloplasty Repair

Background

Transcatheter-based annuloplasty therapies for tricuspid regurgitation have demonstrated significant development over recent years. However, the tricuspid valve and neighboring vasculature and conductive tissue regions can present anatomical and device deployment challenges. This present study investigated the anatomical dimensions and spatial relationships of the cardiac structures essential to percutaneous annuloplasty procedures: the tricuspid annulus (TA), right coronary artery (RCA), and triangle of Koch border region.

Methods

Measurements were derived from computational three-dimensional reconstructions of static magnetic resonance imaging scans of perfusion-fixed human hearts (n = 82) with preserved right-sided heart anatomies. This specimen set included heart samples presenting with prediagnosed atrioventricular valvular regurgitation.

Results

Our anatomical assessments demonstrated that the TA to RCA proximities were intensified with the presence of atrioventricular valvular regurgitation, compared with healthy heart specimens. The minimal distances were frequently located between the lateral and posterior annular points. This annular region corresponds to the RCA distal segments and posterior descending branch origins. Greater portions and incidences of the RCA coursing parallel or inferior to the TA plane were recorded for these diseased hearts. Patient demographic variables (gender, age, and body mass index) were insignificant determinants of change for a majority of our results.

Conclusions

These three-dimensional reconstructions provide insights to guide the development and future iterations of transcatheter tricuspid valve annuloplasty systems with regards to device anchoring, annular geometry, tissue proximities, and implantation considerations.

Understanding tricuspid valve remodelling in atrial fibrillation using three-dimensional echocardiography

AIMS

Atrial fibrillation (AF) has been associated with tricuspid annulus (TA) dilation in patients with severe functional tricuspid regurgitation (TR); however, the impact of AF is less clear in patients without severe TR. Our aim was to characterize TA remodelling in patients with AF in the absence of severe TR using 3D transoesophageal echocardiography (TOE).

METHODS AND RESULTS

Ninety patients underwent clinically indicated transthoracic and TOE: non-structural (NS)-AF (n = 30); AF with left heart disease (LHD) (n = 30), and controls in sinus rhythm (n = 30). Three-dimensional TOE datasets were analysed to measure TA dimensions using novel dedicated tricuspid valve software. The NS-AF group showed biatrial dilatation and normal right ventricular (RV) size with decreased longitudinal function compared to controls, whereas the LHD-AF group showed biatrial dilatation, RV enlargement, decreased biventricular function, and higher systolic pulmonary artery pressure compared with the other groups. Indexed TA area, minimum diameter, maximum diameter, and total perimeter were significantly larger in the NS-AF group than in controls (measurements in end-diastole: 6.4 ± 1.1 vs. 5.0 ± 0.6 cm2/m2, 1.8 ± 0.3 vs. 1.6 ± 0.2 cm/m2, 2.1 ± 0.3 vs. 1.9 ± 0.2 cm/m2, and 6.6 ± 0.9 vs. 5.9 ± 0.7 cm/m2, respectively, all P < 0.05). There was no significant difference in any indexed TA parameter between AF groups. TA circularity index (ratio between minimum and maximal diameters) and TA fractional area change between end-diastole and end-systole were no different among the three groups.

CONCLUSION

AF is associated with right atrial and tricuspid annular remodelling independent of the presence of LHD in patients with intrinsically normal tricuspid leaflets without severe TR.

The Year in Perioperative Echocardiography: Selected Highlights from 2020

This article is the fifth of an annual series reviewing the research highlights of the year pertaining to the subspecialty of perioperative echocardiography for the Journal of Cardiothoracic and Vascular Anesthesia. The authors thank Editor-in-Chief Dr. Kaplan and the editorial board for the opportunity to continue this series. In most cases, these will be research articles that are targeted at the perioperative echocardiography diagnosis and treatment of patients after cardiothoracic surgery; but in some cases, these articles will target the use of perioperative echocardiography in general.

Application of a Series of Two-Dimensional Transesophageal Echocardiographic (2D TEE) Views Across Multiple Axes Improves the Accuracy of Tricuspid Annular Measurements

OBJECTIVES

Quantification of the tricuspid annulus (TA) is an important factor in determining the requirement for tricuspid annuloplasty in cardiac surgery. Three-dimensional echocardiography (3DE) has shown that the TA is biplanar with an antero-posterior longaxis and septo-lateral shortaxis, and that the commonly used 2D TEE (two-dimensional transesophageal echocardiography) four-chamber view (4ChV) underestimates the true TA longaxis. The authors hypothesized that the use of multiple 2D TEE TA views could attain greater TA long-axis measurements and smaller TA short-axis measurements than the 4ChV, and that the 4ChV has a significant but inconsistent bias relative to the maximal TA diameter measured by these views.

DESIGN

Prospective observational study.

SETTING

Adult tertiary teaching hospital.

PARTICIPANTS

45 adult patients.

INTERVENTIONS

Multiplanar 2D TEE assessment of the tricuspid annulus.

MEASUREMENTS AND MAIN RESULTS

Multiplanar assessment reliably produced larger TA long-axis measurements (93% of patients, 95% confidence interval: 81-98%) of (mean [95% confidence interval]) 40 mm (28-50 mm) compared with the 4ChV (34mm [25-44 mm], p < 0.0001) and smaller TA short-axis measurements (29 mm [20-38 mm], p < 0.0001) compared with the 4ChV. TA diameter by 4ChV assessment yielded an average bias of -5.6 mm, with 95% limits of agreement -15 to +3.9 mm compared with the largest TA long-axis measurement by multiplanar assessment.

CONCLUSIONS

Multiplanar 2D TEE assessment of the TA long- and short-axis consistently achieves larger and smaller measurements, respectively, than the 4ChV. The 4ChV also is not a reliable index of the TA longaxis. If the time, proficiency, or equipment required for 3DE TA assessment are unavailable, the use of multiple standard and non-standard 2D TEE TA views may offer an alternative for TA assessment.

Biomechanics of the Tricuspid Annulus: A Review of the Annulus' In Vivo Dynamics With Emphasis on Ovine Data

The tricuspid annulus forms the boundary between the tricuspid valve leaflets and their surrounding perivalvular tissue of the right atrioventricular junction. Its shape changes throughout the cardiac cycle in response to the forces from the contracting right heart myocardium and the blood-valve interaction. Alterations to annular shape and dynamics in disease lead to valvular dysfunctions such as tricuspid regurgitation from which millions of patients suffer. Successful treatment of such dysfunction requires an in-depth understanding of the normal shape and dynamics of the tricuspid annulus and of the changes following disease and subsequent repair. In this manuscript we review what we know about the shape and dynamics of the normal tricuspid annulus and about the effects of both disease and repair based on non-invasive imaging studies and invasive fiduciary marker-based studies. We further show, by means of ovine data, that detailed engineering analyses of the tricuspid annulus provide regionally-resolved insight into the kinematics of the annulus which would remain hidden if limiting analyses to simple geometric metrics.

Tricuspid annular displacement measured by 2-dimensional speckle tracking echocardiography for predicting right ventricular function in pulmonary hypertension: A new approach to evaluating right ventricle dysfunction

This study aimed to determine the ability of tricuspid annular displacement measured by 2-dimensional speckle tracking echocardiography (STE) to predict right ventricular (RV) dysfunction in pulmonary hypertension (PH) patients. Here, we present a new method for assessing RV function that also employs STE and is based on measurement of tricuspid annular displacement.A total of 225 patients were divided into 2 groups according to the pulmonary artery systolic blood pressure (PASP), estimated by echocardiographic measurement of tricuspid regurgitation: group I (PASP ≥50 mm Hg) and group II (36 mm Hg ≤ PASP <50 mm Hg). The tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), RV fractional area change (RVFAC), tissue Doppler-derived tricuspid lateral annular systolic velocity (s'), and the tricuspid annular longitudinal displacement (TMAD) parameters were measured. Thirty patients underwent cardiac magnetic resonance (CMR) examination, and right ventricular ejection fraction (RVEF) was calculated.The conventional parameters as well as the TMAD parameters differed significantly between the 2 groups (all P < .01). Good correlation was observed between the TMAD parameters and CMR-derived RVEF (all P < .01). The TMAD parameters had moderate predictive value for predicting RV dysfunction in PH patients (all P < .01). From receiver operating characteristic curves, we determined the optimal cut-off values for TMAD parameters for detecting RV dysfunction with good sensitivity and specificity.The TMAD parameters can predict the decline of RV function in patients with PH and thus provide new diagnostic indices for clinical management of these patients.

Changes in Tricuspid Annular Geometry in Patients with Functional Tricuspid Regurgitation

OBJECTIVE

To determine whether the indices of tricuspid annular dynamics that signify irreversible tricuspid valvular remodeling can improve surgical decision making by helping to better identify patients with functional tricuspid regurgitation who could benefit from annuloplasty.

DESIGN

Retrospective analysis study.

SETTING

Tertiary hospital.

PARTICIPANTS

A total number of 55 patients were selected, 18 with functional tricuspid valve (TV) regurgitation and 37 normal nonregurgitant TVs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

When comparing the basal, mid, and longitudinal diameters of the right ventricle between the nonregurgitant valve (NTR) group and the functional tricuspid regurgitation (FTR) group, tricuspid annulus was more dilated (p < 0.001, p = 0.001, and p = 0.006, respectively) and less nonplanar (p < 0.001) in the FTR group. At end-systole (ES), the posterolateral-anteroseptal axis was significantly greater in the FTR group than in the NTR group (mean difference = 7.15 mm; p < 0.001). The right ventricle in the FTR group was also significantly dilated with greater leaflet restriction (p = 0.015).

CONCLUSIONS

As compared to NTR TVs, FTR is associated with identifiable indices of tricuspid annular structural changes that are indicative of irreversible remodeling.

Transcatheter Treatment of Functional Tricuspid Regurgitation Using the Trialign Device

Functional tricuspid regurgitation (TR) represents an important unmet need in clinical cardiology given its prevalence, adverse prognostic impact and symptom burden associated with progressive right heart failure. Several transcatheter techniques are currently in early clinical testing to provide alternative treatment options for patients deemed unsuitable for tricuspid valve surgery. Amongst them, the TrialignTM device (Mitralign, Inc.) represents a novel percutaneous tricuspid valve annuloplasty technique, which aims to reduce tricuspid annular dilatation in functional TR by delivering and cinching two pledgeted sutures to the posterior portion of the tricuspid annulus via transjugular access. Early clinical data suggest the Trialign technique is safe and feasible, and associated with an improvement in quality-of-life measures. However, further studies are needed to confirm these data in larger cohorts of patients with longer follow up. In addition, future trials need to address the question whether TR reduction with the Trialign and other devices leads to an improvement in the patient`s functional status and prognosis, over and above medical treatment alone.