Factors associated with development of late significant tricuspid regurgitation after successful left-sided valve surgery

Sex-Based Differences in Concomitant Tricuspid Repair During Degenerative Mitral Surgery

BACKGROUND

Women with mitral valve disease have higher rates of tricuspid regurgitation (TR) than men. Although tricuspid valve repair (TVr) decreases the progression of TR, we hypothesize that there may be sex-based differences in concomitant TVr at the time of mitral valve operations.

METHODS

Adults undergoing mitral valve operation for degenerative disease with moderate or worse preoperative TR at a high-volume center from 2014 to 2023 were identified. Patients with a previous tricuspid intervention were excluded. A multivariable logistic regression identified predictors of concomitant TVr. To evaluate the clinical impact of not performing TVr, a competing risk model compared development of severe TR or valve-related reoperation by sex among patients without TVr.

RESULTS

Most included patients were women (55% [n = 214 of 388]), and the median age was 73 years (quartile 1-quartile 3, 65-79 years). There was no difference in the rate of severe TR by sex (female, 28%; male, 26%; P = .63). The unadjusted rate of concomitant TVr was 57% for women and 73% for men (P < .001). Overall, women had 52% lower adjusted odds of TVr (adjusted odds ratio, 0.48; 95% CI, 0.29-0.81; P = .006), including a lower adjusted rate for moderate TR (47% [95% CI, 45%-49%] vs 66% [95% CI, 64%-69%]) and for severe TR (83% [95% CI, 81%-86] vs 92% [95% CI, 90%-93%]) Among those without TVr, 12% of women and 0% of men had severe TR or required a valve-related reoperation at 4 years (P < .001).

CONCLUSIONS

Women with moderate or severe TR undergoing mitral valve operation for degenerative disease were less likely to receive concomitant TVr, severe TR was more likely to develop, or they would more likely need a valve-related reoperation. Evaluation of sex-based treatment differences is imperative to improve outcomes for women.

Tricuspid Regurgitation in Congestive "End-Organ" Failure: Outline of an Opportunity

Tricuspid regurgitation (TR) is a progressive disease that can be addressed only partially by medical therapy. Progression of TR is associated with worsening end-organ function and worse survival, yet tricuspid valve interventions are usually only performed in advanced stages. Recent evidence suggests a pivotal role for TR and pulsatile venous congestion in the pathophysiology of renal and hepatic dysfunction. This critical knowledge has provided the opportunity to optimally define the appropriate timing of transcatheter tricuspid valve interventions, integrating concurrent or impending functional consequences with severity of TR.

Unveiling Sex Differences in Tricuspid Valve Disease: A Systematic Review and Meta-Analysis of Surgical Management

Tricuspid regurgitation (TR) is a heart condition where blood flows backward through the tricuspid valve. Tricuspid valve disease constitutes a major valvular heart condition that is receiving heightened attention due to tailored treatment options and sex-specific differences in treatment outcomes. The study aims to investigate whether biological sex has a significant influence on the development, progression, and treatment outcomes of tricuspid valve disease in adults. We conducted a comprehensive search to identify studies examining the impact of sex on the pathophysiology of TR as well as treatment outcomes in patients with TR. We searched PUBMED/MEDLINE, SCOPUS, and Excerpta Medica dataBASE (EMBASE) from inception to September 2023 to identify relevant studies. Twelve studies totaling 22,574 patients met our eligibility criteria. These studies were categorized into three subgroups: patients with TR without intervention (3,848 patients, with 48.1% males and 51.9% females), those who underwent open heart surgery (17,498 patients: 46.2% males and 53.8% females), and those who underwent transcatheter tricuspid valve repair/replacement (TTVR; 1,687 patients: 41.6% males and 58.4% females). Analysis revealed no major differences in terms of TR etiology. Males tended to have a slightly lower mean age difference (mean difference (MD): -0.60 years; 95% confidence interval (CI) (-1.49, -0.04); p = 0.10) but had more frequent chronic lung disease (risk ratio (RR): 1.12, 95% CI (1.01, 1.25), p = 0.03). Males showed higher baseline TR volume (MD: 4.11, 95% CI (0.53, 7.68), p = 0.02) and lower left ventricular ejection fraction (MD: -5.85, 95% CI (-6.97, -4.73), p < 0.00001). Following open heart surgery for TR treatment, males required more frequent permanent pacemaker implantation (PPM; RR: 1.57, 95% CI (1.21, 2.03), p = 0.0006). Similarly, TTVR showed a higher need for PPM in males (RR: 1.45, 95% CI (1.10, 1.93), p = 0.010). In-hospital mortality exhibited no sex differences, but males had a slightly elevated late mortality risk. Sex differences in TR patients were notable in baseline characteristics, with males having a higher risk of certain conditions. The more frequent requirement for PPM was a major sex-based difference in terms of prognosis.

Secondary tricuspid valve regurgitation after isolated aortic valve replacement: outcomes and predictors

OBJECTIVES

We sought to assess the evolution of secondary tricuspid regurgitation (TR) after isolated aortic valve replacement (AVR) and its impact on mortality and to identify possible clinical and echocardiographic predictors of persisting and new-onset TR (TR de novo) after isolated AVR.

METHODS

Clinical and echocardiographic data of 441 patients, consecutively operated for isolated AVR between January 2017 and January 2020, were retrospectively collected. Four time points were included: preoperative, discharge, 3-6 months and last available follow-up. We followed patients with at least moderate TR (TR ≥2) over time and monitored the impact on survival. Logistic regression analysis was performed to identify possible predictors of persistent TR and TR de novo.

RESULTS

Median follow-up was 33 months. Incidence of TR ≥2 changed over the time points. Twenty-three percent of patients with preoperative TR ≥2 had persistent TR at 3-6 months follow-up, and this phenomenon was predicted by age at regression analysis. Preoperative TR ≥2 was associated with a 3-fold higher risk to die. At 3- to 6-month follow-up, 12% of patients developed TR de novo. At least moderate preoperative mitral regurgitation (≥2) was predictive of TR de novo.

CONCLUSIONS

Patients with TR ≥2 undergoing isolated AVR had worse long-term survival, and this was particularly evident in the elderly. Older patients were also more prone to have persistent TR after AVR. Some patients developed TR de novo after isolated AVR, but this did not affect survival.

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.

Clinical outcomes and progression rate of tricuspid regurgitation in patients with rheumatic mitral valve disease

OBJECTIVE

A substantial proportion of patients with rheumatic heart disease (RHD) have tricuspid regurgitation (TR). This study aimed to identify the impact of functional TR on clinical outcomes and predictors of progression in a large population of patients with RHD.

METHODS

A total of 645 patients with RHD were enrolled, mean age of 47±12 years, 85% female. Functional TR was graded as absent, mild, moderate or severe. TR progression was defined either as worsening of TR degree from baseline to the last follow-up echocardiogram or severe TR at baseline that required surgery or died. Incidence of TR progression was estimated accounting for competing risks.

RESULTS

Functional TR was absent in 3.4%, mild in 83.7%, moderate in 8.5% and severe in 4.3%. Moderate and severe functional TR was associated with adverse outcome (HR 1.91 (95% CI 1.15 to 3.2) for moderate, and 2.30 (95% CI 1.28 to 4.13) for severe TR, after adjustment for other prognostic variables. Event-free survival rate at 3-year follow-up was 91%, 72% and 62% in patients with no or mild, moderate and severe TR, respectively. During mean follow-up of 4.1 years, TR progression occurred in 83 patients (13%) with an overall incidence of 3.7 events (95% CI 2.9 to 4.5) per 100 patient-years. In the Cox model, age (HR 1.71, 95% CI 1.34 to 2.17), New York Heart Association functional class III/IV (HR 2.57, 95% CI 1.54 to 4.30), right atrial area (HR 1.52, 95% CI 1.10 to 2.10) and right ventricular (RV) dysfunction (HR 2.02, 95% CI 1.07 to 3.84) were predictors of TR progression. By considering competing risk, the effect of RV dysfunction on TR progression risk was attenuated.

CONCLUSIONS

In patients with RHD, functional TR was frequent and associated with adverse outcomes. TR may progress over time, mainly related to right-sided cardiac chambers remodelling.

Insight into tricuspid transcatheter edge-to-edge repair: no longer the forgotten valve

INTRODUCTION

Tricuspid regurgitation (TR) is one of the most prevalent types of valvular heart disease linked to poor prognosis in patients with heart failure and is usually ignored. TR has received considerable attention due to the progressive advancements in transcatheter therapies in recent years.

AREAS COVERED

With relatively solid data and rapid technological advancements, tricuspid transcatheter edge-to-edge repair (T-TEER) is the most frequently employed in a series of tricuspid transcatheter interventional treatments for TR. However, the efficacy and technical benefits of T-TEER are limited because of the unique anatomical characteristics and pathological mechanisms of the tricuspid valve. The aim of this review is to summarize reported data on current status of T-TEER and to provide an expert opinion regarding the challenges it is now experiencing and future development direction and approach.

EXPERT OPINION

T-TEER is a significant treatment for TR, but its effectiveness and technical promotion are limited due to the tricuspid valve unique anatomical characteristics and pathological mechanisms. The selection criteria for suitable patients, the choice of when to intervene, device innovation, the advancement of ultrasound technology, and the volume of evidence in evidence-based medicine all indicate that the disorder of TR will eventually be better treated and understood.

Transcatheter mitral and tricuspid interventions-the bigger picture: valvular disease as part of heart failure

The prevalence of mitral (MR) and tricuspid regurgitation (TR), especially in heart failure (HF) populations, is high. However, the distinct role of atrioventricular valve diseases in HF, whether they are merely indicators of disease status or rather independent contributors in a vicious disease cycle, is still not fully understood. For decades, tricuspid regurgitation (TR) was considered an innocent bystander subsequent to other heart or lung pathologies, thus, not needing dedicated treatment. Recent increasing awareness towards the role of atrioventricular valve diseases has revealed that MR and TR are, in fact, independent predictors of outcome in HF, thus, warranting attention in the HF treatment algorithm. This awareness arose, especially, with the development of minimally invasive transcatheter solutions providing new treatment options, which can also be used for patients considered as having increased surgical risk. However, outcomes of such transcatheter treatments have, in part, been sub-optimal and likely influenced by the status of the concomitant HF disease. Thus, this review aims to summarize data on the current understanding regarding the role of MR and TR in HF, how HF impacts outcomes of transcatheter MR and TR interventions, and how the understanding of this relationship might help to identify patients that benefit most from these therapies, which have proven to be lifesaving in properly selected candidates.

Prognostic Predictors of Tricuspid Regurgitation Worsening after Mitral Regurgitation Surgery with Mild Tricuspid Regurgitation

We aimed to investigate the prevalence and predictors of postoperative tricuspid regurgitation (TR) worsening in patients with mitral regurgitation (MR) and concomitant ≤mild TR. A total of 620 patients underwent surgery for MR from 2013 to 2017. Of these, 260 had ≤mild preoperative TR and no concomitant tricuspid valve surgery and were enrolled in this single-center retrospective study. The primary endpoint was postoperative worsening of ≥moderate TR. The primary endpoint occurred in 28 of 260 patients (11%) during the follow-up period [median: 4.1 years (interquartile range: 2.9-6.1 years)]. In the multivariable analysis, age, female sex, and left atrial volume index (LAVI) were significant predictors of the primary outcome during intermediate-term follow-up (age: hazard ratio [HR] 1.05 per 1-year increment, 95% confidence interval [CI] 1.02-1.10, p = 0.003; female sex: HR 3.53, 95% CI 1.61-7.72, p = 0.002; LAVI: HR 1.17 per 10-mL/m² increment, 95% CI 1.07-1.26, p < 0.001). The optimal LAVI cut-off value for predicting postoperative TR worsening was 79 mL/m² (area under the curve: 0.69). A high LAVI (>79 mL/m²) was significantly associated with a low rate of freedom from postoperative TR worsening compared with a low LAVI (≤79 mL/m²) (82.6% vs. 93.9% at 5 years, respectively; log-rank p = 0.008). In patients with ≤mild preoperative TR and no concomitant tricuspid surgery, the rate of postoperative TR worsening was 11% during intermediate-term follow-up. LA enlargement in patients with MR and ≤mild preoperative TR was significantly associated with postoperative TR worsening.

[Interventional treatment of heart failure : Stents and valves]

The pharmacotherapy of heart failure has evolved in recent years and with the aid of new classes of drugs symptomatic and prognostic improvements can be achieved in patients with heart failure. Heart failure is particularly frequently associated with coronary artery disease or higher grade, often functional valve defects. In the context of the underlying disease, the operative risk is often increased, so that interventional treatment is preferred over surgical treatment options in interdisciplinary heart teams. Promising approaches with very different challenges are emerging for interventional myocardial revascularization and percutaneous correction of high-grade aortic valve stenosis or functional mitral or tricuspid valve regurgitation. It has consistently been shown that an elaborate diagnostic work-up and differentiated patient selection are decisive to achieve a prognostic or symptomatic benefit in these patients using interventional treatment. While awaiting further study data on this topic, the integration of a multidisciplinary heart team is essential to ensure a complementary and balanced therapeutic approach for patient-centered care in this complex patient population.

Concomitant Transcatheter Edge-to-Edge Treatment of Secondary Tricuspid and Mitral Regurgitation: An Expert Opinion

Secondary (functional) tricuspid regurgitation (sTR) is common in patients with mitral regurgitation (MR). Because combined valvular heart disease affects long-term survival, in comparison with isolated MR or tricuspid regurgitation, it is essential to offer patients adequate treatment. Despite considerable experience, no conclusive data are yet available on the prognostic impact of concomitant tricuspid valve surgery at the time of mitral valve surgery. Emerging transcatheter treatments offer the opportunity to treat both conditions (MR and sTR) simultaneously or in a stepwise fashion. This review provides a clinical overview on available data regarding the rationale for treatment of sTR in patients with relevant MR undergoing mitral transcatheter edge-to-edge repair, focusing on clinical and anatomical selection criteria.

His-Purkinje system pacing reduced tricuspid regurgitation in patients with persistent atrial fibrillation after left-sided valve surgery

Background & objective

Tricuspid regurgitation after left-sided valve surgery was a common and difficult problem. Atrial fibrillation was considered to be an important etiology of tricuspid regurgitation. His-Purkinje system pacing (HPSP) was a physiological pacing method, which could prevent and treat heart failure and might reduce tricuspid regurgitation. Our study aimed to investigate the effect of HPSP on tricuspid regurgitation in patients with persistent atrial fibrillation after left-sided valve surgery.

Methods

This study was a retrospective study. The 3-year patient review focused on those who underwent permanent cardiac pacemaker implantation of HPSP after mitral valve and/or aortic valve replacement from Jan 1st, 2019 to Jan 1st, 2022. HPSP included His bundle pacing (HBP) or left bundle branch pacing (LBBP). Clinical data collected included electrocardiogram, pacing parameters, ultrasonic cardiogram parameters and chest x-ray at implantation and 3-month follow up. Univariate and multivariate linear regression analysis of tricuspid regurgitation velocity were performed.

Results

A total of 44 patients was retrospectively reviewed. Eight patients who had undergone implantation of HPSP after left-sided heart valve replacement were enrolled in the study. All patients had persistent atrial fibrillation. Three of them received HBP and five underwent LBBP. At 3-month follow-up, the tricuspid regurgitation grade was significantly lower than that before implantation (P = 0.007). The tricuspid regurgitation velocity significantly decreased (317 ± 74 cm/s vs. 261 ± 52 cm/s, P = 0.022) and tricuspid valve pressure gradient (PG) reduced (42 ± 21 mmHg vs. 28 ± 10 mmHg, P = 0.040). The cardiothoracic ratio of patients was significantly lower than that before implantation (0.61 ± 0.08 vs. 0.64 ± 0.09, P = 0.017). The NYHA classification of patients also improved (P = 0.013). In multivariate liner regression analysis, the pacing ratio (β = 0.736, P = 0.037) was an independent determinant of tricuspid regurgitation velocity variation.

Conclusion

HPSP might reduce tricuspid regurgitation and improve cardiac function in patients with persistent atrial fibrillation after left-sided valve surgery.

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.

Right ventricle remodeling after transcatheter tricuspid leaflet repair in patients with functional tricuspid regurgitation: Lessons from the surgical experience

Clinically significant tricuspid regurgitation (TR) is common and associated with excess mortality. At the same time right ventricular (RV) failure is a complex clinical syndrome that results from many causes, but is often associated with long-term prognosis. Whilst results of isolated tricuspid valve (TV) surgery are often unsatisfactory and limited by the prohibitive risk of most patients, the recent development of percutaneous recovery techniques has opened new scenarios. In consideration of the complexity of the mechanisms that lead to right heart failure and RV dysfunction it is important to understand the real advantages that percutaneous TV treatment can offer, more specifically the effect of TR reduction on RV remodeling in the setting of functional tricuspid regurgitation (fTR).

Efficacy and Safety of Concomitant Tricuspid Repair in patients undergoing Mitral Valve Surgery: a systematic review and meta-analysis

BACKGROUND

Tricuspid valve surgery is recommended for both, classes I and IIb while being essential for class II patients undergoing MVS.

AIMS/OBJECTIVES

The meta-analysis aimed to evaluate the efficacy and safety of tricuspid valve repair in patients undergoing MVS.

METHODS

We systematically searched PubMed, Embase, and Google Scholar through January 2022, and studies comparing patients with tricuspid valve repair (TVR) and those without TVR were selected. The primary outcome was 30-day and all-cause mortality.

RESULTS

In this meta-analysis, 20 studies were included with a patient population of 72,422. 30-day mortality studies (RR: 1.14, 95% CI [0.69, 1.87]) and all-cause mortality studies (RR: 1.16, 95% CI [0.86, 1.57]) at follow-up both were insignificant. From the secondary outcomes, pacemaker insertion (RR: 2.62, 95% CI [2.24, 3.06]), new-onset TR or progression (RR: 0.32, 95% CI [0.16, 0.66]), stroke (RR: 1.22, 95% CI [1.05, 1.42]), cross-clamp time (WMD: 17.67, 95% CI [13.96, 21.37]), surgery time (WMD: 43.59, 95% CI [37.07, 50.10]), ICU time (WMD: 19.50, 95% CI [9.31, 29.67]), and ventilation time (WMD: 6.62, 95% CI [0.69, 12.55]) were significant. Whereas major bleeding events, atrial fibrillation, renal failure, heart failure hospitalization, postoperative MI, wound infection, early or prolonged morbidity, cardiopulmonary bypass time, and duration of hospital stay were non-significant.

CONCLUSION

No significant difference was observed between patients undergoing TVR with MVS in comparison to MVS group only for the primary outcomes, 30-day mortality and all-cause mortality, respectively.

Surgical management of tricuspid regurgitation: a new algorithm to minimise recurrent tricuspid regurgitation

Introduction

Recurrent tricuspid regurgitation (TR) is frequently observed after cardiac surgery; however, the correct approach remains controversial. We developed an algorithm for action on the tricuspid valve (TV) and conducted a 1-year follow-up study. The aim was to assess the efficacy of the algorithm to minimise residual TR after TV surgery. The hypothesis was that the TR rate at 1 year would be reduced by selecting the surgical approach in accordance with a set of preoperative clinical and echocardiographic variables.

Methods

A prospective, observational, single-centre study was performed in 76 consecutive patients with TV involvement. A protocol was designed for their inclusion, and data on their clinical and echocardiographic characteristics were gathered at 3 months and 1-year postsurgery. The treatment of patients depended on the degree of TR. Surgery was performed in all patients with severe or moderate-to-severe TR and in those with mild or moderate TR alongside the presence of certain clinical or echocardiographic factors. They underwent annuloplasty or extended valve repair when the TV was distorted. If repair techniques were not feasible, a prosthesis was implanted. Residual TR rates were compared with published reports, and predictors of early/late mortality and residual TR were evaluated.

Results

TR was functional in 69.9% of patients. Rigid ring annuloplasty was performed in 35.7% of patients, De Vega annuloplasty in 27.1%, extended repair in 11.4% and prosthetic replacement in 25.7%. TR was moderate or worse in 8.19% of patients (severe in 3.27%) at 1 year postintervention. No clinical, surgical or epidemiological variables were significantly associated with residual TR persistence, although annulus diameter showed a close-to-significant association. Total mortality was 12.85% for all causes and 10% for cardiovascular causes. In multivariate analysis, left ventricular ejection fraction was related to both early and late mortality.

Conclusions

Severe residual TR was significantly less frequent than reported in other series, being observed in less than 4% of patients at 1-year postsurgery.

The factors associated with progression of tricuspid regurgitation after left-sided double valve replacement in propensity score matched analysis

Background

This study aims to investigate the association of progression of tricuspid regurgitation following double-valve replacement by comparing the tricuspid valve repair and no repair groups, and to analyze outcomes of patients with non-repaired mild-to-moderate tricuspid regurgitation.

Methods

Between January 2014 and September 2017, a total of 157 patients (74 males, 83 females; mean age: 51.7±13.7 years; range, 18 to 78 years) who underwent aortic and mitral valve replacements with/without concomitant tricuspid valve repair were retrospectively analyzed. The patients were divided into two groups: no-repair (n=78) and repair groups (n=79). The primary outcome measure was development of more than moderate tricuspid regurgitation during follow-up.

Results

The data were evaluated according to propensity score matched analysis. The progression of tricuspid regurgitation was significantly increased in the no-repair group (p=0.006). Rheumatic etiology was independently associated with the presence of postoperative moderateto- severe tricuspid regurgitation (p=0.004, odds ratio: 3.40). There was no statistically significant difference between the groups in terms of the potential complications and mortality and survival rates. A multivariable subgroup analysis for the baseline mild-to-moderate tricuspid regurgitation without repair showed that rheumatic etiology was an independent factor for the progression of postoperative tricuspid regurgitation (p=0.01).

Conclusion

Our study results demonstrated that rheumatic etiology was an independent marker for increased tricuspid regurgitation and it was also independently associated with increased tricuspid regurgitation in patients with mild-to-moderate non-repaired patients. The degree of tricuspid regurgitation was improved in the repair group during follow-up.

Transcatheter treatment for tricuspid valve disease

Approximately 4% of subjects aged 75 years or more have clinically relevant tricuspid regurgitation (TR). Primary TR results from anatomical abnormality of the tricuspid valve apparatus and is observed in only 8-10% of the patients with tricuspid valve disease. Secondary TR is more common and arises as a result of annular dilation caused by right ventricular enlargement and dysfunction as a consequence of pulmonary hypertension, often caused by left-sided heart disease or atrial fibrillation. Irrespective of its aetiology, TR leads to volume overload and increased wall stress, both of which negatively contribute to detrimental remodelling and worsening TR. This vicious circle translates into impaired survival and increased heart failure symptoms in patients with and without reduced left ventricular ejection fraction. Interventions to correct TR are underutilised in daily clinical practice owing to increased surgical risk and late patient presentation. The recently introduced transcatheter tricuspid valve interventions aim to address this unmet need. Dedicated expertise and an interdisciplinary Heart Team evaluation are essential to integrate these new techniques successfully and select patients. The present article proposes a standardised approach to evaluate patients with TR who may be candidates for transcatheter interventions. In addition, a state-of-the-art review of the available transcatheter therapies, the main criteria for patient and device selection, and information concerning the remaining uncertainties are provided.

When Aortic Stenosis Is Not Alone: Epidemiology, Pathophysiology, Diagnosis and Management in Mixed and Combined Valvular Disease

Aortic stenosis (AS) may present frequently combined with other valvular diseases or mixed with aortic regurgitation, with peculiar physio-pathological and clinical implications. The hemodynamic interactions between AS in mixed or combined valve disease depend on the specific combination of valve lesions and may result in diagnostic pitfalls at echocardiography; other imaging modalities may be helpful. Indeed, diagnosis is challenging because several echocardiographic methods commonly used to assess stenosis or regurgitation have been validated only in patients with the single-valve disease. Moreover, in the developed world, patients with multiple valve diseases tend to be older and more fragile over time; also, when more than one valvular lesion needs to address the surgical risk rises together with the long-term risk of morbidity and mortality associated with multiple valve prostheses, and the likelihood and risk of reoperation. Therefore, when AS presents mixed or combined valve disease, the heart valve team must integrate various parameters into the diagnosis and management strategy, including suitability for single or multiple transcatheter valve procedures. This review aims to summarize the most critical pathophysiological mechanisms underlying AS when associated with mitral regurgitation, mitral stenosis, aortic regurgitation, and tricuspid regurgitation. We will focus on echocardiography, clinical implications, and the most important treatment strategies.

Prognostic implication of right ventricular dysfunction and tricuspid regurgitation following transcatheter aortic valve replacement

OBJECTIVES

Right ventricular (RV) dysfunction and tricuspid regurgitation (TR) are associated with adverse outcomes in severe aortic stenosis (AS) patients. Our aim was to evaluate the association between ≥moderate TR and RV dysfunction on long-term mortality following transcatheter aortic valve replacement (TAVR).

METHODS

A retrospective analysis of the Israeli multicenter TAVR registry among 4,344 consecutive patients, with all-cause mortality as the main outcome measure.

RESULTS

Echocardiographic assessment of TR grade and RV dysfunction was available for 3,733 and 1,850 patients, of whom ≥moderate TR and RV dysfunction was noted for 478(13%) and 78(4%), respectively. The mean follow-up time was 2.9 ± 2.3 years. In univariate models, ≥Moderate TR and ≥moderate RV dysfunction were associated with increased long-term mortality (HR 1.45, 95% CI 1.24-1.69, p < .001 and HR 1.73, 95% CI 1.21-2.47, p = 0.003, respectively). These finding did not remained significant after adjusting to echocardiographic parameters. A subset of patients with no improvement in RV function had the highest long-term mortality risk (HR 3.3, 95% CI 1.95-5.7, p < .001).

CONCLUSION

When adjusted to multiple echocardiographic characteristics baseline ≥Moderate TR and ≥moderate RV dysfunction were not associated with long-term mortality following TAVR. Persistent RV dysfunction following TAVR was associated with the highest risk for mortality.

The Society of Thoracic Surgeons Adult Cardiac Surgery Database: 2021 Update on Echocardiography

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) is the world's premier clinical outcomes registry for adult cardiac surgery and a driving force for quality improvement in cardiac surgery. Echocardiographic data provide a wealth of hemodynamic, structural, and functional data and have been part of STS ACSD data collection since its inception. An increasing body of evidence suggests that the use of echocardiography in patients undergoing cardiac surgery has a positive impact on postoperative outcomes. In this report, we describe and summarize the type and rate of reporting of echocardiography-related variables in the STS ACSD, including the Adult Cardiac Anesthesiology Module, from July 2017 to December 2019 for the most frequently performed cardiac surgical procedures. With this review, we aim to increase awareness of the importance of collecting accurate and consistent echocardiography data in the STS ACSD and to highlight opportunities for growth and improvement.

Association between computed tomography-derived tricuspid annular dimensions and prognosis: insights from whole-beat computed tomography assessment

Aims

Tricuspid regurgitation (TR) has been associated with outcome in patients treated with transcatheter aortic valve implantation (TAVI). Tricuspid annulus (TA) dimensions are associated with TR. However, the TA is highly dynamic during the cardiac cycle, and the interaction between the TA dimensions, TR, and patient prognosis has never been evaluated. This study aimed to characterize the dynamics of the TA along with the cardiac cycle and its association with prognosis in patients undergoing TAVI.

Methods and results

Patients with severe aortic stenosis who underwent whole-beat computed tomography (n = 393, mean age 80 ± 7 years, 53% male) were included. The ratio between anterior-posterior (AP) and septal-lateral (SL) diameter of the TA was calculated at end-systole (ES), mid-diastole (MD), and end-diastole (ED) to characterize the TA shape throughout the cardiac cycle. The primary endpoint was all-cause mortality. During a median follow-up of 3.6 (1.7–5.5) years, 146 patients died. While all the TA parameters at ES and MD were not associated with all-cause mortality, a low AP/SL ratio at ED (more circular geometry) was independently related with all-cause mortality (hazard ratio: 4.717, 95% confidence interval: 1.481–15.152; P = 0.009). In addition, a more circular TA shape at ED (AP/SL ratio < 1.20) was also associated with more right atrial and ventricular dilation, more frequently significant TR, and a higher prevalence of atrial fibrillation.

Conclusion

Circular remodelling of the TA shape at ED is associated with more right atrial and ventricular dilation, and a higher long-term mortality after TAVI. The evaluation of the TA shape at ED may be a useful parameter in the risk stratification of patients undergoing TAVI.

Hospital outcome of concomitant tricuspid annuloplasty during totally endoscopic mitral valve surgery: a propensity matched study

Background

This study aimed to determine how concomitant tricuspid annuloplasty (TAP) affects the clinical outcomes of patients undergoing totally endoscopic mitral valve surgery.

Methods

This was a single-centre, retrospective study. Between January 2019 and June 2020, 143 patients who underwent totally endoscopic mitral valve surgery in our institution were enrolled. Ninety-two patients who underwent isolated mitral valve surgery were categorized into the minimally invasive mitral valve surgery (MIMVS) group (n=92), and patients who underwent mitral valve surgery with concomitant TAP were categorized into the MIMVS-TAP (n=51) group. Clinical data were collected from all patients, including demographic and perioperative data. We conducted propensity score matching (PSM) by using one-to-one ratio nearest-neighbour matching for baseline demographic data and tricuspid valve-related parameters. Forty patients in each group were matched in this way. Parametric and nonparametric tests were performed for data analysis.

Results

Statistically, postoperative mortality within 30 days was not significantly different between the two groups (P=1). No differences were found in serious adverse events, such as stroke or third-degree conduction block, between the two groups after 1:1 PSM (P=1 and P=0.480, respectively). The mean operation time for the MIMVS+TAP group was longer (232.13±36.05 min) than that for the MIMVS group (204.25±28.49 min; P<0.001). The same was true for the cardiopulmonary bypass (CPB) time (169.48±25.96 vs. 153.10±23.00 min; P=0.004) and aortic clamp time (110.80±17.37 vs. 101.00±14.38 min; P=0.005). The duration of the intensive care unit stay and the overall postoperative length of stay were not different between the two groups (P=0.734 and P=0.472, respectively). The postoperative systolic pulmonary artery pressure differed between the two groups [38.00±8.45 (MIMVS); 33.65±7.34 (MIMVS + TAP), P=0.022].

Conclusions

Our study showed that totally endoscopic mitral valve surgery with concomitant TAP is just as safe and effective as isolated totally endoscopic mitral valve surgery, even with a long surgery duration. Our study also suggested that totally endoscopic mitral valve surgery with concomitant TAP can improve tricuspid function in patients.

Effect of Concomitant Tricuspid Annuloplasty on Early Outcomes of Mitral Valve Replacement: A Study on Rheumatic Heart Disease Patients

Introduction

Mitral valve abnormalities in rheumatic heart disease commonly lead to functional tricuspid regurgitation. Tricuspid annuloplasty (TA) is often performed in these cases along with mitral valve replacement (MVR). Our aim was to compare the perioperative morbidity and mortality among those patients that underwent mitral valve replacement with tricuspid annuloplasty versus those that underwent isolated mitral valve replacement.

Methods

A retrospective analysis of 158 patients that underwent mitral valve replacement, with or without tricuspid annuloplasty, secondary to rheumatic heart disease between January 2017 and August 2020. Patients who underwent additional cardiothoracic surgical procedures (aortic valve replacement and coronary artery bypass grafting) were excluded to reduce confounders.

Results

The study group consisted of 158 patients (mean age 41; 73 male, 85 female) that underwent MVR with TA (n=22; 13.9%) or without TA (n=136; 86.1%). Both groups had similar comorbidity frequencies and medication history. Preoperative echocardiography showed a comparable degree of pulmonary hypertension and ejection fraction between the two groups. The TA+MVR group had similar intraoperative (81.8% vs 66.9%; p=0.161) and postoperative (45.5% vs 45.6%; p=0.991) blood products usage compared to the MVR only group. Concurrent TA resulted in similar in-hospital mortality (4.5% vs 4.4%; p=0.977) as well as early postoperative complications, namely, prolonged ICU stay (13.6% vs 10.3%; p=0.639), prolonged ventilation (0 vs 2.2%; p=0.482), re-intubation (9.1% vs 2.9%; p= 0.161), and reopening for bleeding tamponade (0 vs 5.1%; p=0.276).

Conclusions

TA concurrently with MVR does not appear to increase in-hospital mortality or early postoperative complications.

Optimal Tricuspid Annular Size for Tricuspid Annuloplasty in Patients with Less-Than-Moderate Functional Tricuspid Regurgitation

Background

We evaluated the association between tricuspid annular dilatation and the development of moderate or severe tricuspid regurgitation (TR). Additionally, we determined the optimal tricuspid annular dilatation threshold to use as an indicator for tricuspid annuloplasty in patients with less-than-moderate functional TR (FTR).

Methods

Between August 2007 and December 2014, 227 patients with less-than-moderate TR underwent mitral valve surgery without a tricuspid valve (TV) procedure. The TV annular diameter was measured via transthoracic echocardiography. The TV annular index (TVAI) was calculated as the TV annular diameter divided by the body surface area. The mean duration of echocardiographic follow-up was 42.0 months (interquartile range, 9.3–66.6 months).

Results

Eight patients (3.5%) developed moderate or severe TR. The rate of freedom from development of moderate or severe TR at 5 years was 96.2%. TV annular diameter, left atrial diameter, preoperative atrial fibrillation, and TVAI were found to be associated with the development of moderate or severe TR in the univariate analysis. A cut-off TVAI value of 19.8 mm/m² was found to predict the development of moderate or severe TR, and a significant difference was observed in the development of TR of this severity based on this cut-off (p<0.001).

Conclusion

The progression of TR was not infrequent in patients with untreated less- than-moderate FTR. An aggressive treatment approach can be helpful to prevent the progression of FTR for patients with risk factors, especially TVAI greater than 19.8 mm/m².

Male-female differences in characteristics and early outcomes of patients undergoing tricuspid valve surgery: a national cohort study in the Netherlands

OBJECTIVES

This study aims to explore male-female differences in baseline and procedural characteristics, and outcomes of patients undergoing isolated or concomitant tricuspid valve (TV) surgery.

METHODS

All TV procedures registered between 2007 and 2016 in the database of the Netherlands Association for Cardio-Thoracic Surgery were analysed. Logistic regression analyses with interaction terms were used to determine whether sex was associated with hospital mortality.

RESULTS

Five thousand five hundred and eighty-two patients underwent TV surgery [isolated: N = 685 (49% male), TVrepair: N = 5286 (50% male) and TVreplacement: N = 250 (46% male)]. In the TVrepair group, females were significantly older, had less prior percutaneous/surgical coronary interventions, less extracardiac arteriopathies, a lower prevalence of renal impairment, less endocarditis, a lower prevalence of preoperative critical condition, less recent myocardial infarction, less concomitant coronary artery bypass grafting (CABG) and, in case of concomitant mitral valve surgery, less concomitant mitral valve repair compared to males. In the TVreplacement group, females more often had a history of prior valve surgery and less prior CABG. Hospital mortality for males and females was 7.0% (N = 183) and 6.1% (N = 163), P = 0.241 in the TVrepair group and 2.6% (N = 3) and 8.8% (N = 12), P = 0.074 in the TVreplacement group. Sex was not associated with hospital mortality (odds ratio (OR) 1.14, 95% confidence interval (CI) 0.88-1.48; P = 0.322). Sex demonstrated a significant interaction with the parameter 'critical preoperative condition' (OR 0.44, 95% CI 0.22-0.90; P = 0.026).

CONCLUSIONS

Substantial differences in patient and procedural characteristics existed between male and female patients undergoing TV surgery, although sex was not a derterminant for hospital mortality. Nevertheless, sex interacted with a critical preoperative condition, indicating the usefulness of separate risk factor models for males and females requiring TV surgery.

Impact of tricuspid regurgitation with and without repair during aortic valve replacement

BACKGROUND

Long-term outcomes of aortic valve replacement (AVR) are worse in patients with tricuspid regurgitation (TR), but the impact of concomitant tricuspid valve intervention remains unclear. The purpose of this study was to determine the effect of tricuspid intervention in patients with TR undergoing AVR.

METHODS

Patients undergoing AVR in a regional Society of Thoracic Surgeons database (2001-2017) were stratified by severity of TR and whether or not they underwent concomitant tricuspid intervention. Operative morbidity and mortality were compared between the 2 groups. Further analysis was performed using propensity score-matched pairs.

RESULTS

Among 17,483 patients undergoing AVR, 8984 (51%) had no TR, 7252 (41%) had mild TR, 1060 (6%) had moderate TR, and 187 (1%) had severe TR. Overall, more severe TR was associated with higher morbidity and mortality. Tricuspid intervention was performed in 104 patients (0.6%), including 0.2% of patients with mild TR, 2% of those with moderate TR, and 31% of those with severe TR. In the propensity score-matched analysis, there was not a statistically significant difference in operative mortality between the 2 groups (18% vs 9%; P = .16), but there was significantly higher composite major morbidity (51% vs 26%; P = .006) in the tricuspid intervention group compared with those without surgical TR correction.

CONCLUSIONS

Increasing severity of TR is associated with higher rates of morbidity and mortality after AVR. Correction of TR at the time of surgical AVR is not associated with increased operative mortality and has been shown to improve long-term outcomes.

Sick Sinus Syndrome After the Maze Procedure Performed Concomitantly With Mitral Valve Surgery

Background

To characterize the development of sick sinus syndrome (SSS) after the additive maze procedure (MP) during mitral valve surgery.

Methods and Results

Follow‐up data (median, 3.6 years) of 750 patients with a prevalence of rheumatic cause of 57.6% were analyzed. SSS occurred in 35 patients with a time‐dependent increase: the incidence rates at 1, 2, and 4 years after surgery were 2.9%, 3.7%, and 4.3%, respectively. The additive MP showed higher risks of SSS development (hazard ratio, 7.44; 95% confidence interval, 3.45–16.05; P<0.001) and pacemaker implantation (hazard ratio, 3.61; 95% confidence interval, 1.95–6.67; P<0.001). Patients who developed SSS showed higher 4‐year rates of clinical events (death, stroke, and hospital admission) (67.5±8.5% versus 33.0±1.9%; P<0.001). After adjustment for age and preoperative peak systolic pulmonary artery pressure, the lesion extent (biatrial versus left atrial MP), not the underlying cause (rheumatic versus nonrheumatic), was independently associated with SSS development (hazard ratio, 3.58; 95% confidence interval, 1.08–11.86; P=0.037). The adverse effect of the biatrial MP was confirmed in patients with trivial or mild preoperative tricuspid regurgitation showing higher SSS incidence (4.6±1.4% versus 1.0±0.7%; P=0.023), not in those with moderate‐to‐severe tricuspid regurgitation (6.8±1.7% versus 3.8±3.8%; P=0.337). Recurrence of atrial fibrillation was not associated with the lesion extent of the MP.

Conclusions

After the additive MP, the ongoing risk of SSS development should be acknowledged irrespective of the underlying cause. Considering additive risk of biatrial MP with similar atrial fibrillation recurrence rate, minimizing lesion extent is warranted.

Predictors and Outcomes of Persistent Tricuspid Regurgitation After Transcatheter Aortic Valve Implantation

Persistent tricuspid regurgitation (TR) after transcatheter aortic valve implantation (TAVI) has been reported to increase mortality. The aim of this study was to investigate clinical and echocardiographic determinants and outcome of persistent TR after TAVI. We reviewed 1,085 patients who underwent TAVI. Among them, 100 patients who had ≥moderate TR without organic dysfunction of the tricuspid valve apparatus were studied. Preprocedural and follow-up transthoracic echocardiography after TAVI were analyzed. After TAVI, patients were divided into persistent TR group and improved TR group. Clinical event was defined as all-cause mortality and readmission for heart failure within 1,000 days. Fifty-three (53%) patients had persistent TR, whereas 47 (47%) patients had improved TR. Risk of clinical event was significantly higher in the persistent TR group compared with the improved TR group. Atrial fibrillation (AF) and tricuspid annular dimension (TAD; p <0.05 for all) were independent predictors of persistent TR. Receiver operating characteristic curve showed the optimal cut-off value of TAD for predicting persistent TR was 37 mm. The combination of AF and TAD ≥37 mm was associated with persistent TR (p <0.001). In conclusion, AF and dilated TAD before TAVI predicted persistent TR which was associated with higher all-cause mortality and readmission for heart failure.

Short-Term Effects of Tolvaptan in Tricuspid Insufficiency Combined with Left Heart Valve Replacement-Caused Volume-Overload Patients: Results of a Prospective Pilot Study

OBJECTIVES

Our objective was to explore the effects of tolvaptan as a new therapeutic approach in patients with right heart failure with tricuspid insufficiency (TI).

METHODS

This prospective, multicenter, non-randomized controlled pilot study enrolled patients (N = 40) with TI from the Shanghai Chest Hospital and Shanghai Tongren Hospital who fulfilled inclusion criteria between March 2015 and June 2016. Participants were assigned to receive either tolvaptan combined with torasemide (n = 20) or torasemide monotherapy (n = 20; control group). The primary endpoints were changes in patient weight and in tricuspid annular plane systolic excursion (TAPSE) after 10 days of treatment. The secondary endpoints included net fluid balance and cardiac functions before and after medication from the first to the tenth day of treatment. Safety was evaluated by monitoring adverse and serious adverse events.

RESULTS

TAPSE significantly increased in the tolvaptan group compared with the control group after 10 days of medication (P = 0.029). Daily weight losses in the tolvaptan group significantly increased as the time of treatment increased (time × group, P = 0.022). Recovery to New York Heart Association (NYHA) grade I occurred 4 days earlier in the tolvaptan group. In addition, the net fluid balance and median net fluid balance were significantly higher in the tolvaptan group. Eight adverse events and one serious adverse event were recorded in the tolvaptan group and 15 adverse events were recorded in the control group.

CONCLUSIONS

Our results indicate that tolvaptan might be a useful and safe drug to improve heart function in patients with right heart failure with TI after left heart valve replacement.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier no. NCT02644616.

Tricuspid regurgitation and the right ventricle in risk stratification and timing of intervention

Tricuspid regurgitation natural history and treatment remains poorly understood. Right ventricular function is a key factor in determining prognosis, timing for intervention and longer-term outcome. The right ventricle is a thin walled chamber with a predominance of longitudinal fibres and a shared ventricular septum. In health, the low-pressure pulmonary circulation results in a highly compliant RV well equipped to respond to changes in preload but sensitive to even small alterations in afterload. In Part 1 of this article, discussion focuses on key principles of ventricular function assessment and the importance of right ventricular chamber size, volumes and ejection fraction, particularly in risk stratification in tricuspid regurgitation. Part 2 of this article provides an understanding of the causes of tricuspid regurgitation in the contemporary era, with emphasis on key patient groups and their management.

Right-Sided Heart Structural and Functional Remodeling in Mitral Regurgitation Secondary to Mitral Valve Prolapse

Preoperative evaluation of the mitral valve but also of tricuspid valve and right ventricular (RV) function is mandatory in primary mitral regurgitation (MR) secondary to mitral valve prolapse (MVP). Tricuspid annulus (TA) diameter plays a pivotal role in the surgical decision to perform preventive combined tricuspid valve annuloplasty. Cardiac magnetic resonance (CMR) is the gold standard for the assessment of RV size and function. Based on 70 consecutive patients (17 women; mean age 64 ± 12) with severe MR secondary to MVP referred for CMR, we sought to assess RV geometry and function and TA dimensions and to study the interaction between TA dilatation and right-sided cardiac chambers. Frequency of RV dilatation, RV systolic dysfunction, and TA dilatation (TA diameter ≥ 40 or 21 mm/m²) were 11%, 51%, and 49%, respectively. Left ventricular (LV) end-diastolic volume index was the only independent predictor of RV dilatation. Presence of symptoms, larger LV end-diastolic volume index, and LV ejection fraction <60% were independently associated with RV dysfunction. Absolute TA diameter was 36 ± 6 mm and TA diameter index was 20 ± 3 mm/m². Reproducibility TA diameter measurement was excellent (coefficient of variation ≤10%). TR velocity >220 cm/s (odds ratio = 20.17; [3.57 to 113.90]; p = 0.001 and right atrial volume index ≥ 38 ml/m² (odds ratio = 13.44; [3.57 to 50.54]; p = 0.0001) were independent predictors of TA diameter ≥40 or 21 mm/m². CMR provides accurate right-sided cardiac chambers assessment and may help surgical planning of concomitant tricuspid valve annuloplasty before mitral valve repair in severe MR secondary to MVP. In conclusion, TA dilatation, RV enlargement, and dysfunction are related to pulmonary pressure and left-sided cardiac chambers enlargement, reflecting the long-standing consequences of severe MR.

Functional Tricuspid Regurgitation in Mitral Valve Disease

Functional tricuspid regurgitation is a common finding in patients with left-sided heart disease. If left untreated, it may reduce survival, limit functional capacity and cause end-organ dysfunction. Annulus dilation and leaflet tethering due to right ventricle remodeling are 2 major pathophysiologic mechanisms in functional tricuspid regurgitation. Even if surgical treatment remains the gold standard, indication and timing of surgical interventions remain the object of debate in the medical community. More recently, numerous transcatheter therapies have been developed in order to offer less invasive options to patients who otherwise would have a high risk of mortality and morbidity with surgical interventions.