Development of a Consensus Algorithm to Improve Interobserver Agreement and Accuracy in the Determination of Tricuspid Regurgitation Severity

Transcatheter tricuspid valve interventions: Current devices and associated evidence

Tricuspid regurgitation (TR) is a common finding in patients with chronic cardiopathy, and often a marker of an advanced disease. Being silent or with symptoms intertwined with the primitive left heart disease, TR has often been neglected, leading to the late referral of patients with advanced right-heart failure. Hence, isolated tricuspid surgery has been associated with high morbidity and mortality rates, the worse of all valve interventions, and medical management has been limited to symptomatic treatment. In this context, percutaneous therapies for severe TR have gained traction, addressing the unmet therapeutic gap for a less invasive disease-modifying management. The aim of this review is to provide an updated overview on transcatheter tricuspid valve interventions, focusing on devices' characteristics, associated evidence, and future perspectives.

Transcatheter treatment of severe tricuspid regurgitation

PURPOSE OF REVIEW

Severe tricuspid regurgitation is a commonly prevalent valvular heart disease that is an independent adverse prognostic marker. However, the majority of patients with tricuspid regurgitation are managed medically; isolated tricuspid valve surgery is rarely performed, partly owing to high associated in-hospital mortality. Therefore, several transcatheter tricuspid valve interventions (TTVIs) that have been developed over the last few years to address this unmet clinical need.

RECENT FINDINGS

The early experience with TTVI has shown that most devices can be safely implanted with excellent rates of technical success and acceptable safety outcomes. Most TTVI recipients have significant improvement in tricuspid regurgitation severity, functional class, and quality of life. Recent retrospective data also suggest mortality benefit of TTVI compared with medical management. There are several issues that need to be addressed prior to widespread adoption of TTVI, including more effective tricuspid regurgitation reduction and need for longer term efficacy data.

SUMMARY

TTVI has emerged as an attractive treatment option for management of high-risk patients with tricuspid regurgitation. In this review, we will discuss the anatomical considerations specific to tricuspid valve, patient selection, preprocedure planning, and summarize the current evidence and future perspectives on TTVI.

Clinical impact and 'natural' course of uncorrected tricuspid regurgitation after implantation of a left ventricular assist device: an analysis of the European Registry for Patients with Mechanical Circulatory Support (EUROMACS)

OBJECTIVES

Data on the impact and course of uncorrected tricuspid regurgitation (TR) during left ventricular assist device (LVAD) implantation are scarce and inconsistent. This study explores the clinical impact and natural course of uncorrected TR in patients after LVAD implantation.

METHODS

The European Registry for Patients with Mechanical Circulatory Support was used to identify adult patients with LVAD implants without concomitant tricuspid valve surgery. A mediation model was developed to assess the association of TR with 30-day mortality via other risk factors. Generalized mixed models were used to model the course of post-LVAD TR. Joint models were used to perform sensitivity analyses.

RESULTS

A total of 2496 procedures were included (median age: 56 years; men: 83%). TR was not directly associated with higher 30-day mortality, but mediation analyses suggested an indirect association via preoperative elevated right atrial pressure and creatinine (P = 0.035) and bilirubin (P = 0.027) levels. Post-LVAD TR was also associated with increased late mortality [hazard ratio 1.16 (1.06–1.3); P = 0.001]. On average, uncorrected TR diminished after LVAD implantation. The probability of having moderate-to-severe TR immediately after an implant in patients with none-to-mild TR pre-LVAD was 10%; in patients with moderate-to-severe TR pre-LVAD, it was 35% and continued to decrease in patients with moderate-to-severe TR pre-LVAD, regardless of pre-LVAD right ventricular failure or pulmonary hypertension.

CONCLUSIONS

Uncorrected TR pre-LVAD and post-LVAD is associated with increased early and late mortality. Nevertheless, on average, TR diminishes progressively without intervention after an LVAD implant. Therefore, these data suggest that patient selection for concomitant tricuspid valve surgery should not be based solely on TR grade.

Assessment of tricuspid annulus: anatomic and echocardiographic correlation

Tricuspid regurgitation is associated with a poor outcome and its quantification remains a challenge. Tricuspid annulus dilatation is one of the parameters that influences clinical decision-making. The aim of this study was to compare the use of 2D transoesophageal echocardiography with surgical assessment for the measurement of the tricuspid annulus. Sixty-one cardiac patients (median age 64 years) were included in the study. Echocardiographic tricuspid annulus measurements were obtained from four chamber and transgastric short axis views and compared with the surgical measurements of this valve. The study was approved by the Ethics Committee of our institution. The tricuspid annulus measurements were obtained from the four chamber and the short axis views in 57 and 49 patients, respectively, while surgical measurement was performed in all 61 patients. Bland-Altman analysis of 49 tricuspid annulus-matched dimensions of the short axis view and surgical values showed a mean bias of 0.223 mm/m², with limits of agreement of -5.86 to 6.31 mm/m². Echocardiographic measurements of the tricuspid annulus dimension were accurate (90% sensitivity and 90% specificity for a four chamber view cut-off value ≥ 24.5 mm/m², and 89% sensitivity and 97% specificity for a short axis view cut-off value ≥ 37.6 mm/m², P < 0.0001; both cases) for detecting directly assessed annular dilatation by the surgeon in the operative field. Echocardiographic values of tricuspid annulus dimension have a good predictive value to detect surgically assessed annular dilatation and may help identify patients who require surgical tricuspid intervention.

Transcatheter Interventions for Tricuspid Valve Disease: What to Do and Who to Do It On

Tricuspid valve disease, and particularly the management of severe tricuspid regurgitation (TR), has gained momentum in recent years. Although it is well known that this frequent condition is associated with poor clinical outcomes, these patients have been classically managed medically, leading to end-stage right ventricular heart failure. Moreover, late referral to surgery has contributed to a high rate of periprocedural complications and in-hospital surgical mortality. Thus, the development of a less invasive catheter-based therapy would be of high clinical relevance in this context. Several transcatheter tricuspid valve intervention (TTVI) devices have been developed in recent years. The particular characteristics of the tricuspid valve (large noncalcific annulus, presence of chief surrounding structures such as the conduction system or the right coronary artery) make multimodality imaging (eg, transesophageal echocardiography, computed tomography) key in the preprocedural assessment of TTVI. According to their mechanism of action and therapeutic target, TTVI includes transcatheter repair either with coaptation or annuloplasty systems, caval valve devices, and transcatheter tricuspid valve replacement. The initial TTVI experience showed that most procedures were well tolerated, with high procedural success and low in-hospital and early mortality. Also, most TTVI recipients improved their functional status and recent data suggest improved outcomes compared with medical management. However, the rate of significant residual TR after transcatheter tricuspid valve repair remains high and very scarce data exist on longer term (beyond 6-12 months) outcomes. The present review provides an overview regarding the framework of chronic TR and TTVI therapeutic options, and describes the updated current evidence in this challenging field.

Direct measurement of atrioventricular valve regurgitant jets using 4D flow cardiovascular magnetic resonance is accurate and reliable for children with congenital heart disease: a retrospective cohort study

BACKGROUND

3D-time resolved flow (4DF) cardiovascular magnetic resonance (CMR) with retrospective analysis of atrioventricular valve regurgitation (AVVR) allows for internal validation by multiple direct and indirect methods. Limited data exist on direct measurement of AVVR by 4DF CMR in pediatric congenital heart disease (CHD). We aimed to validate direct measurement of the AVVR jet as accurate and reliable compared to the volumetric method (clinical standard by 2D CMR) and as a superior method of internal validation than the annular inflow method.

METHODS

We identified 44 consecutive patients with diverse CHD referred for evaluation of AVVR by CMR. 1.5 T or 3 T scanners, intravenous contrast, and a combination of parallel imaging and compressed sensing were used. Four methods of measuring AVVR volume (RVol) were used: volumetric method (VOL; the clinical standard) = stroke volume by 2D balanced steady-state free precession - semilunar valve forward flow (SLFF); annular inflow method (AIM) = atrioventricular valve forward flow [AVFF] - semilunar valve net flow (SLNF); and direct measurement (JET). AVFF was measured using static and retrospective valve tracking planes. SLFF, SLNF, AVFF, and JET were measured by 4DF phase contrast. Regurgitant fraction was calculated as [RVol/(RVol+SLNF)]× 100. Statistical methods included Spearman, Wilcoxon rank sum test/Student paired t-test, Bland Altman analysis, and intra-class coefficient (ICC), where appropriate.

RESULTS

Regurgitant fraction by JET strongly correlated with the indirect methods (VOL and AIM) (ρ = 0.73-0.80, p < 0.001) and was similar to VOL with a median difference (interquartile range) of - 1.5% (- 8.3-7.2%; p = 0.624). VOL had weaker correlations with AIM and JET (ρ = 0.69-0.73, p < 0.001). AIM underestimated RF by 3.6-6.9% compared to VOL and JET, p < 0.03. Intra- and inter- observer reliability were excellent for all methods (ICC 0.94-0.99). The mean (±standard deviation) inter-observer difference for VOL was 2.4% (±5.1%), p < 0.05.

CONCLUSIONS

In a diverse cohort of pediatric CHD, measurement of AVVR using JET is accurate and reliable to VOL and is a superior method of internal validation compared to AIM. This study supports use of 4DF CMR for measurement of AVVR, obviating need for expert prospective prescription during image acquisition by 2D CMR.

Impact of tricuspid regurgitation on postoperative outcomes after non-cardiac surgeries

Objective

Tricuspid regurgitation (TR) severity has known adverse implications, its impact on patients undergoing non-cardiac surgery (NCS) remains unclear. We sought to determine the impact of TR on patient outcomes after NCS.

Methods

We performed a retrospective cohort study in patients undergoing NCS. Outcomes in patients with moderate or severe TR were compared with no/trivial TR after adjusting for baseline characteristics and revised cardiac risk index (RCRI). The primary outcome was defined as 30-day mortality and heart failure (HF), while the secondary outcome was long-term mortality.

Results

Of the 7064 patients included, 312 and 80 patients had moderate and severe TR, respectively. Thirty-day mortality was higher in moderate TR (adjusted OR 2.44, 95% CI 1.25 to 4.76) and severe TR (OR 2.85, 95% CI 1.04 to 7.79) compared with no/trivial TR. There was no difference in 30-day HF in patients with moderate TR (OR 1.48, 95% CI 0.90 to 2.44) or severe TR (OR 1.42, 95% CI 0.60 to 3.39). The adjusted HR for long-term mortality in moderate TR was 1.55 (95% CI 1.31 to 1.82) and 1.87 (95% CI 1.40 to 2.50) for severe TR compared with no/trivial TR.

Conclusion

Increasing TR severity has higher postoperative 30-day mortality in patients undergoing NCS, independent of RCRI risk factors, ejection fraction or mitral regurgitation. Severity of TR should be considered in risk stratification for patients undergoing NCS.

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.

Tricuspid flow and regurgitation in congenital heart disease and pulmonary hypertension: comparison of 4D flow cardiovascular magnetic resonance and echocardiography

BACKGROUND

Tricuspid valve (TV) regurgitation (TR) is a common complication of pulmonary hypertension and right-sided congenital heart disease, associated with increased morbidity and mortality. Estimation of TR severity by echocardiography and conventional cardiovasvular magnetic resonance (CMR) is not well validated and has high variability. 4D velocity-encoded (4D-flow) CMR was used to measure tricuspid flow in patients with complex right ventricular (RV) geometry and varying degrees of TR. The aims of the present study were: 1) to assess accuracy of 4D-flow CMR across the TV by comparing 4D-flow CMR derived TV effective flow to 2D-flow derived effective flow across the pulmonary valve (PV); 2) to assess TV 4D-flow CMR reproducibility, and 3) to compare TR grade by 4D-flow CMR to TR grade by echocardiography.

METHODS

TR was assessed by both 4D-flow CMR and echocardiography in 21 healthy subjects (41.2 ± 10.5 yrs., female 7 (33%)) and 67 RV pressure-load patients (42.7 ± 17.0 yrs., female 32 (48%)). The CMR protocol included 4D-flow CMR measurement across the TV, 2D-flow measurement across the PV and conventional planimetric measurements. TR grading on echocardiographic images was performed based on the international recommendations. Bland-Altman analysis and intra-class correlation coefficients (ICC) were used to asses correlations and agreement.

RESULTS

TV effective flow measured by 4D-flow CMR showed good correlation and agreement with PV effective flow measured by 2D-flow CMR with ICC = 0.899 (p < 0.001) and mean difference of -1.79 ml [limits of agreement -20.39 to 16.81] (p = 0.084). Intra-observer agreement for effective flow (ICC = 0.981; mean difference - 1.51 ml [-12.88 to 9.86]) and regurgitant fraction (ICC = 0.910; mean difference 1.08% [-7.90; 10.06]) was good. Inter-observer agreement for effective flow (ICC = 0.935; mean difference 2.12 ml [-15.24 to 19.48]) and regurgitant fraction (ICC = 0.968; mean difference 1.10% [-7.96 to 5.76]) were comparable. In 25/65 (38.5%) TR grade differed by at least 1 grade using 4D-flow CMR compared to echocardiography.

CONCLUSION

TV effective flow derived from 4D-flow CMR showed excellent correlation to PV effective flow derived from 2D-flow CMR, and was reproducible to measure TV flow and regurgitation. Twenty-five out of 65 patients (38.5%) were classified differently by at least one TR grade using 4D-flow CMR compared to echocardiography.

High Agreement and High Prevalence: The Paradox of Cohen's Kappa

Background:

Cohen's Kappa is the most used agreement statistic in literature. However, under certain conditions, it is affected by a paradox which returns biased estimates of the statistic itself.

Objective:

The aim of the study is to provide sufficient information which allows the reader to make an informed choice of the correct agreement measure, by underlining some optimal properties of Gwet’s AC1 in comparison to Cohen’s Kappa, using a real data example.

Method:

During the process of literature review, we have asked a panel of three evaluators to come up with a judgment on the quality of 57 randomized controlled trials assigning a score to each trial using the Jadad scale. The quality was evaluated according to the following dimensions: adopted design, randomization unit, type of primary endpoint. With respect to each of the above described features, the agreement between the three evaluators has been calculated using Cohen’s Kappa statistic and Gwet’s AC1 statistic and, finally, the values have been compared with the observed agreement.

Results:

The values of the Cohen’s Kappa statistic would lead to believe that the agreement levels for the variables Unit, Design and Primary Endpoints are totally unsatisfactory. The AC1 statistic, on the contrary, shows plausible values which are in line with the respective values of the observed concordance.

Conclusion:

We conclude that it would always be appropriate to adopt the AC1 statistic, thus bypassing any risk of incurring the paradox and drawing wrong conclusions about the results of agreement analysis.

Current transcatheter devices to treat functional tricuspid regurgitation with discussion of issues relevant to clinical trial design

Functional or secondary tricuspid regurgitation (TR) has seen increased attention in recent times as relationships with clinically-relevant outcomes have come to light. Despite the association of increased mortality with significant TR, the disease remains under-recognized and thus relatively untreated. In addition, the disease itself has not been extensively studied and the interactions between annular dilatation, right heart disease and pulmonary hypertension are poorly understood. However, the high mortality and recurrence rate with current surgical replacement or repair techniques is well recognised, opening the door to transcatheter therapies for functional TR. The current perspective reviews the rationale for transcatheter solutions, describes some of the current approaches and discusses the ongoing questions of a poorly-studied condition which may limit the design of clinical trials for this disease.

Trials of Quality Improvement in Imaging

Cardiovascular imaging plays a central role in the diagnosis and treatment of cardiovascular disease. Recently, increased emphasis has been placed on quality in cardiovascular imaging, and it is becoming a central priority for various stakeholders, including patients, physicians, and payers. The changing health care landscape and associated challenges imposed on cardiac imagers, including reductions in reimbursement and growing need for pre-authorization, have also helped bring quality metrics to the forefront. Continuous quality improvement initiatives provide the framework for the team of physicians, technical staff members, administrators, and other health care professionals to deliver high-quality care. Efforts to improve quality in cardiac imaging have started to form the foundation for numerous research studies in this arena, and although few in number, randomized control trials have begun to emerge. This review highlights quality improvement studies focusing on appropriate use education, reporting, and radiation dose reduction in cardiovascular imaging.

State-of-the-Art Review of Echocardiographic Imaging in the Evaluation and Treatment of Functional Tricuspid Regurgitation

Functional or secondary tricuspid regurgitation (TR) is the most common cause of severe TR in the Western world. The presence of functional TR, either isolated or in combination with left heart disease, is associated with unfavorable natural history. Surgical mortality for isolated tricuspid valve interventions remains higher than for any other single valve surgery, and surgical options for repair do not have consistent long-term durability. In addition, as more patients undergo transcatheter left valve interventions, developing transcatheter solutions for functional TR has gained greater momentum. Numerous transcatheter devices are currently in early clinical trials. All patients require an assessment of valve morphology and function, and transcatheter devices typically require intraprocedural guidance by echocardiography. The following review will describe tricuspid anatomy, define echocardiographic views for evaluating tricuspid valve morphology and function, and discuss imaging requirements for the current transcatheter devices under development for the treatment of functional TR.

Tricuspid Regurgitation: 2015 Reflections and Re-evaluation

OPINION STATEMENT

The tricuspid valve is, in fact, anatomically and functionally more complex than its left-sided counterpart-the mitral valve. Patients may develop tricuspid regurgitation from a variety of mechanisms. While current guidelines provide a very basic approach to tricuspid regurgitation (TR) evaluation, more recent techniques, particularly 3D echocardiography, have provided novel insights into how we can ascertain the mechanism and severity of tricuspid regurgitation, how the tricuspid valve adapts to disease and, importantly, how we assess the effects of TR on right ventricular size and function. We anticipate that these advances will soon yield dividends that will help us decide on approaches to treatment and timing of surgery.