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The deteriorating nature of severe functional tricuspid regurgitation (FTR) has led to the heightened interest in this pathology. However, therapies are heterogeneous and an ideal technique is uncertain. The hemodynamic impact on the cardiac chamber following therapeutic repairs has not been well studied, while its analysis could be used to predict the treatment success. In this study, the hemodynamics of the right ventricle (RV) after 1 ) clover edge-to-edge tricuspid repair, and 2 ) double orifice tricuspid repair was evaluated in three right heart models using an ex vivo pulsatile platform emulating severe FTR with the aid of stereoscopic particle image velocimetry. Although all repairs substantially reduced tricuspid regurgitant area, they resulted in a more than 50% reduction in diastolic tricuspid valve (TV) opening area. Splitting the TV orifice into multiple smaller orifices by both repairs eliminated the ring-shaped vortical structure inside the RV observed in FTR cases. Postrepair RV domain was mostly occupied with irregular vortical features and isolated vortex residuals. Moreover, vortical features varied among repair samples, indicating enhanced sensitivity of RV flow to postrepair TV morphology. Compared with clover repair, double orifice subjected the RV to enhanced swirling motions and exposed more regions to vortical motions, potentially indicating better rinsing and lower risk of mural thrombus formation. Double orifice repair increased the levels of RV mean kinetic energy and viscous energy loss than those observed in clover repair, although the impact of these on the cardiac efficiency remains unclear. These preliminary insights could be used to improve future treatment design and planning. NEW & NOTEWORTHY While clover and double orifice tricuspid repairs markedly improved leaflet coaptation, they substantially reduced diastolic tricuspid opening area. Postrepair right ventricle (RV) exhibited specific hemodynamic traits, including the loss of ring-shaped vortical structure and the enhanced sensitivity of RV flow to postrepair tricuspid valve morphology. Compared with clover technique, double orifice repair led to higher swirling motions in the RV domain, which could indicate lower risk of mural thrombus formation.

There has been a resurgence of interest in the treatment of severe functional tricuspid regurgitation (FTR) due to the awareness of its poor outcomes and potential percutaneous therapies. Kay bicuspidization has been adapted in percutaneous therapies but its clinical outcome remains uncertain. The present study evaluates the efficacy of Kay repair in a novel ex vivo pulsatile system. Porcine tricuspid valve (TV) (n = 3) was extracted and incorporated into a patient-specific silicon right ventricle (RV) emulating severe FTR, on which Kay repair was subsequently performed. TV area metrics and RV hemodynamic assessment by means of stereo-scopic particle image velocimetry were quantified in both FTR and post-repair conditions. Bicuspidization led to significant increase in cardiac output although the overall increment due to this approach alone was generally small, possibly due to existence of residual TR and the large reduction in TV opening area. Kinetic energy and viscous loss levels were increased post-repair, especially during diastolic filling. Main vortex structures generally maintained post-procedural. However, there was enhanced swirling motion in larger RV domain. Although this might reduce mural-thrombus risk, the relatively more complex vortex phenomenon likely resulted in elevated viscous loss observed and may potentially impact long-term adaptation. The RV hemodynamic alteration after tricuspid repair could be used to predict the success of these future transcatheter solutions.

Background: Transcatheter aortic valve replacement (TAVR) is being increasingly performed in patients with bicuspid aortic valve stenosis (AS)., Objectives: This study sought to compare the procedural and clinical outcomes in patients with bicuspid versus tricuspid AS from the Bicuspid AS TAVR multicenter registry., Methods: Outcomes of 561 patients with bicuspid AS and 4,546 patients with tricuspid AS were compared after propensity score matching, assembling 546 pairs of patients with similar baseline characteristics. Procedural and clinical outcomes were recorded according to Valve Academic Research Consortium-2 criteria., Results: Compared with patients with tricuspid AS, patients with bicuspid AS had more frequent conversion to surgery (2.0% vs. 0.2%; p = 0.006) and a significantly lower device success rate (85.3% vs. 91.4%; p = 0.002). Early-generation devices were implanted in 320 patients with bicuspid and 321 patients with tricuspid AS, whereas new-generation devices were implanted in 226 and 225 patients with bicuspid and tricuspid AS, respectively. Within the group receiving early-generation devices, bicuspid AS had more frequent aortic root injury (4.5% vs. 0.0%; p = 0.015) when receiving the balloon-expanding device, and moderate-to-severe paravalvular leak (19.4% vs. 10.5%; p = 0.02) when receiving the self-expanding device. Among patients with new-generation devices, however, procedural results were comparable across different prostheses. The cumulative all-cause mortality rates at 2 years were comparable between bicuspid and tricuspid AS (17.2% vs. 19.4%; p = 0.28)., Conclusions: Compared with tricuspid AS, TAVR in bicuspid AS was associated with a similar prognosis, but lower device success rate. Procedural differences were observed in patients treated with the early-generation devices, whereas no differences were observed with the new-generation devices., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Heterotopic implantation of transcatheter tricuspid valve is a new treatment option for tricuspid regurgitation. Transcatheter tricuspid valves are implanted onto the cavoatrial junction in order to avoid the challenging task of anchoring the valve onto the complex tricuspid valve annulus. However, little is known about optimum extent of oversizing of the valved stent in a vena cava. In this study, we implanted valves of the same diameter onto the larger sized inferior vena cava (IVC) and a smaller sized superior vena cava (SVC). The valve in the IVC was oversized by 10.7% while the valve in the SVC was oversized by 21.6%. Finite element analysis was performed (i) to assess the strain on the nitinol stent during manufacturing and deployment; (ii) the stents were deployed in a patient-specific vena cava model and the intramural stress of the vena cava was calculated computationally. These valves were fabricated and placed in a silicone model of a patient-specific right atrium which was part of a mock circulatory system that emulated the patho-physiological flow rate and pressure of a patient with tricuspid regurgitation. Flow measurements were conducted by particle image velocimetry (PIV). It was found that the maximum crimping strain on the nitinol stent was 6.85% which was lower than the critical threshold of 10%. The maximum stress on the vena cava was located at the spot where the hooks met the wall. The maximum stress on the IVC was 0.5098 MPa while the maximum stress on the SVC was 0.7 MPa. The maximum Reynolds shear stress (mRSS) in the vena cava was found to be higher in the IVC than SVC with the highest mRSS being 1741 dynes/cm(2) found in the region of high flow during the peak flow phase. The overtly oversized valve in the SVC did not cause flow disturbances and exhibited mostly laminar flows. The mRSS at the downstream of the vena cava valve and the middle of the atrium remained at low magnitudes. However, velocity fluctuations were high in the IVC in all the time points measured. In conclusion, oversizing the valve may assist anchorage; yet, careful consideration should be taken in choosing the extent of oversizing as it may lead to adverse effects.

Right-sided infective endocarditis (IE) related to intravenous drug use (IVDU) can follow an acute fulminant course. However, there is limited information on its longer-term clinical outcomes. We assessed a cohort of consecutive patients who presented with IVDU complicated by severe tricuspid valve regurgitation to determine their presentation, treatment, and long-term outcomes. In this study, severe tricuspid regurgitation (TR) was defined by the European Association of Cardiovascular Imaging criteria at initial presentation to the hospital. Thirty-three patients with a mean age of 35 ± 18 years (72% males) presented with IVDU associated with severe TR. At the initial presentation, 15 patients were in septic shock and required inotropes. 26 patients had septic pulmonary emboli; 10 patients had associated metastatic systemic sites of infection of which 5 patients had central nervous system (CNS) involvement. Three patients were in disseminated intravascular coagulation (DIC) and 1 patient had multi-organ failure (MOF), but not requiring dialysis or mechanical ventilation. Most patients had large tricuspid valve vegetations of >20mm. Eleven patients underwent surgery with 18% perioperative mortality. The Median follow-up was 6.4 years (0.5–11.4). Recurrent IE occurred in one-third of patients, the overall incidence of heart failure and Atrial fibrillation (AF) on follow-up was low in all 3 groups. Five-year survival was 94%. Acute severe TR following associated endocarditis IVDU results in a fulminant initial presentation, but a longer-term prognosis is good with surgical and medical treatment. [ABSTRACT FROM AUTHOR]

The deteriorating nature of severe functional tricuspid regurgitation (FTR) has led to the heightened interest in this pathology. However, therapies are heterogeneous and an ideal technique is uncertain. The hemodynamic impact on the cardiac chamber following therapeutic repairs has not been well studied, while its analysis could be used to predict the treatment success. In this study, the hemodynamics of the right ventricle (RV) after 1) clover edge-to-edge tricuspid repair, and 2) double orifice tricuspid repair was evaluated in three right heart models using an ex vivo pulsatile platform emulating severe FTR with the aid of stereoscopic particle image velocimetry. Although all repairs substantially reduced tricuspid regurgitant area, they resulted in a more than 50% reduction in diastolic tricuspid valve (TV) opening area. Splitting the TV orifice into multiple smaller orifices by both repairs eliminated the ring-shaped vortical structure inside the RV observed in FTR cases. Postrepair RV domain was mostly occupied with irregular vortical features and isolated vortex residuals. Moreover, vortical features varied among repair samples, indicating enhanced sensitivity of RV flow to postrepair TV morphology. Compared with clover repair, double orifice subjected the RV to enhanced swirling motions and exposed more regions to vortical motions, potentially indicating better rinsing and lower risk of mural thrombus formation. Double orifice repair increased the levels of RV mean kinetic energy and viscous energy loss than those observed in clover repair, although the impact of these on the cardiac efficiency remains unclear. These preliminary insights could be used to improve future treatment design and planning. NEW & NOTEWORTHY While clover and double orifice tricuspid repairs markedly improved leaflet coaptation, they substantially reduced diastolic tricuspid opening area. Postrepair right ventricle (RV) exhibited specific hemodynamic traits, including the loss of ring-shaped vortical structure and the enhanced sensitivity of RV flow to postrepair tricuspid valve morphology. Compared with clover technique, double orifice repair led to higher swirling motions in the RV domain, which could indicate lower risk of mural thrombus formation. [ABSTRACT FROM AUTHOR]

Abstract: The concept of heterotopic implantation of transcatheter tricuspid valve is new and has shown promising results thus far. While the Reynolds shear stress values measured in the vicinity of this valve are relatively low, the values at some time points are higher than the threshold of platelet activation. Hence, in this study, we aim to reduce these values with an innovative stent design. It was shown that the Reynolds shear stress values measured were lower than those of valves made of generic stent design and the maximum Reynolds shear stress values in the vicinity of the valves was very low (∼10 dynes/cm2). The results also depicted the interesting flow phenomenon of this non‐physiological treatment approach. Thus, this study has shown that bicaval valves could potentially be considered as a minimally invasive option to treat tricuspid regurgitation and valve design improvements could reduce the flow disturbances that were observed. [ABSTRACT FROM AUTHOR]

Background: Severe functional tricuspid regurgitation (fTR) is associated with adverse clinical outcomes and remains under-treated. There is recent interest in this disease due to emerging tricuspid valve therapies. However, the timing and selection of patients who may benefit from treatment is uncertain. Risk factors associated with mortality after diagnosis of severe fTR may help guide treatment.Aim: We studied patients with severe fTR to assess predictors of mortality.Methods: We retrospectively identified consecutive patients who had severe fTR diagnosed on transthoracic echocardiography in a single academic tertiary hospital. These were categorised into atrial fibrillation (AF)- and non-AF-related groups. Patient characteristics and echocardiographic parameters were collected. We then analysed the collected parameters on their impact on occurrence of mortality and also on the time to mortality.Results: A total of 635 patients with severe fTR were studied (41.6 % male, mean age of 68.6±15.4 yrs). There were 130 (20.5%) in the AF-related group and 505 (79.5%) in the non-AF related-group. Median follow-up duration was 774 days, during which 154 (24.3%) deaths occurred within the first year. Older age on diagnosis, reduced left ventricular ejection fraction (LVEF) (<50%), high pulmonary systolic pressure (PASP) (>50 mmHg) and a prior history of heart failure admissions were associated with occurrence of mortality. Older age on diagnosis, reduced LVEF, and high PASP were also found to be associated with time to mortality.Conclusions: For patients diagnosed with severe fTR, advanced age on diagnosis, prior heart failure admission, LVEF <50%, and PASP >50 mmHg are associated with mortality. These factors could form the basis of future studies that determine the timing and decision to intervene in patients with severe fTR. [ABSTRACT FROM AUTHOR]

Intra-ventricular flow dynamics has recently emerged as an important evaluation and diagnosis tool in different cardiovascular conditions. The formation of vortex pattern during the cardiac cycle has been suggested to play important epigenetic and energy-modulation roles in cardiac remodelling, adaptations and mal-adaptations. In this new perspective, flow alterations due to different cardiovascular procedures can affect the long-term outcome of those procedures. Especially, repairs and replacements performed on atrioventricular valves are likely to exert direct impact on intra-ventricular flow pattern. In this review, current consensus around the roles of vortex dynamics in cardiac function is discussed. An overview of physiological vortex patterns found in healthy left and right ventricles as well as post-operative ventricular flow phenomenon owing to different atrioventricular valvular procedures are reviewed, followed by the summary of different vortex identification schemes used to characterise intraventricular flow. This paper also emphasises on future research directions towards a comprehensive understanding of intra-cardiac flow and its clinical relevance. The knowledge could encourage more effective pre-operative planning and better outcomes for current clinical practices. [ABSTRACT FROM AUTHOR]

Background: Severe functional tricuspid regurgitation (TR) is associated with poor outcomes. We sought to examine the predictors of early mortality and if severe TR with heart failure (HF) is a stage too late for intervention. Methods: Our study retrospectively identified 635 consecutive patients who had severe functional TR diagnosed on trans-thoracic echocardiography in an academic medical centre from 2000- 2016. We assessed their underlying comorbidities and analyzed their impact on survival. Results: Mean follow-up was 1084 days. There were 371 (58.4%) females, and the mean age at diagnosis was 68.6 years. The mean Body Mass Index, left ventricular ejection fraction (LVEF) and pulmonary artery systolic pressure (PASP) were 23.8 kg/m2, 48.6% and 53.8 mmHg, respectively. Pre-existing or incident atrial fibrillation (AF) and ischemic heart disease were 420 (66.1%) and 312 (49.1%) respectively. A total of 307 (48.4%) patients had HF prior and 123 (19.4%) had incident HF. The mechanisms for severe TR were left heart disease ± pulmonary hypertension (72 %), AF with annular modeling (20.4 %), and isolated right ventricular dilatation (7.6 %). There were 286 (45.0%) deaths during follow up, with 154 (24.3%) dying within a year. The median survival was about 690 days. Multivariate analysis revealed that age at diagnosis (HR 1.03, p: 0.001), prior HF admission (HR: 1.31, p: 0.048), PASP of more than 50 mmHg (HR: 1.48, p: 0.004) and LVEF less than 50% (HR: 1.35, p: 0.041) were significantly associated with time to death. Conclusion: In patients with severe functional TR, advanced age, prior HF admission, LVEF <50%, PASP >50 mm Hg are malignant features, representing an advanced stage of the disease and associated with early mortality. Ability to interpret effectiveness of trans-catheter therapies in this group of patients may be limited, which future clinical intervention trials should take into account. [ABSTRACT FROM AUTHOR]