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Mitral regurgitation (MR) coexists in a significant proportion of patients with severe aortic stenosis (AS), and portends inferior therapeutic outcomes. In severe AS, MR is thought to contribute to a low-flow state by decreasing forward stroke volume. We investigated concomitant MR on the clinical and echocardiographic features of patients with "paradoxical" low-flow (PLF) and normal-flow (NF) severe AS. Clinical and echocardiographic profiles of 886 consecutive patients with index echocardiographic diagnosis of severe AS (AVA < 1.0 cm 2 ) were analysed retrospectively. All patients had preserved ejection fraction (LVEF  ≥ 50%, n = 645), and were divided into PLF (stroke volume index, SVI < 35 mL/m 2 ) and NF AS. They were then further subdivided based on the presence or absence of moderate-or-severe MR (msMR). A higher prevalence of concomitant msMR was observed in patients with PLF AS (14.9%; n = 33/221) compared to those with NF AS (8.0%; n = 34/424). Concomitant msMR was associated with echocardiographic features of increased diastolic dysfunction in both PLF AS and NF AS patients, as evidenced by increased LA diameter (PLF AS 52.9 ± 12.5 to 43.9 ± 8.9 mm; NF AS 29.6 ± 10.8 to 42.4 ± 8.8 mm; p < 0.001) and increased transmitral E/A ratio (PLF AS 1.26 ± 0.56 to 0.92 ± 0.43; NF AS 1.19 ± 0.63 to 0.94 ± 0.45; p = 0.004). Amongst patients with NF AS, msMR was additionally associated with increased E:e' ratio (25.5 ± 15.1 vs 19.3 ± 10.8; p = 0.025). Concomitant MR was more common in PLF AS compared to NF. Although possibly related to the MR, patients severe AS and MR appeared to have more severe diastolic dysfunction. Further studies are warranted to evaluate prognosis and guide management.

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.

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., (Copyright © 2018. Published by Elsevier Ltd.)

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.

Severe tricuspid regurgitation (TR) is life-threatening but is often undertreated. Many patients with severe TR are denied heart valve replacement surgery because their old age or comorbidities predispose them to a higher risk of surgical complications associated with open-heart surgery. With the advent of transcatheter technology, it is now possible to deliver the valve to the desired location without the need for open-heart surgery. However, presently, there is no commercially available transcatheter tricuspid valve. This may be due to the complex tricuspid valve anatomy, which lacks an anchorage zone for the percutaneous valves. In view of this drawback, we have recently developed and tested two percutaneous caval heart valves that are designed to deploy at the vena cava and atrium junction. The hemodynamic characteristics of these valves are tested in a mock circulatory system with patient-specific silicone atrium and vena cava, which emulates the physiological pressure and flow conditions at the right side of the human heart. Particle imaging velocimetry results showed that flow velocity and the associated Reynolds shear stress (RSS) and the turbulent kinetic energy (TKE) downstream of the valves increased after the implantation of the valves. A maximum flow velocity of 0.94 m/s was observed at the region downstream of the percutaneous valve at the superior vena cava (SVC). Maximum RSS value of 2076.1 dynes/cm(2) was observed downstream of the valve at the inferior vena cava during the deceleration phase while maximum TKE measured was 572.6 J/m(3) at the upstream of the valve in the SVC during the peak flow phase. While these values appear high, they are significantly lower than those reported in prosthetic mitral and aortic valves. Hence, caval stented valves can be potentially considered as a minimally invasive option to treat TR., (Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

Aims Sex-specific thresholds of aortic valve calcification (AVC) have been proposed and validated in Caucasians. Thus, we aimed to validate their accuracy in Asians. Methods and results Patients with calcific aortic stenosis (AS) from seven international centres were included. Exclusion criteria were ≥moderate aortic/mitral regurgitation and bicuspid valve. Optimal AVC and AVC-density sex-specific thresholds for severe AS were obtained in concordant grading and normal flow patients (CG/NF). We included 1263 patients [728 (57%) Asians, 573 (45%) women, 837 (66%) with CG/NF]. Mean gradient was 48 (26–64) mmHg and peak aortic velocity 4.5 (3.4–5.1) m/s. Optimal AVC thresholds were: 2145 Agatston Units (AU) in men and 1301 AU in women for Asians; and 1885 AU in men and 1129 AU in women for Caucasians. Overall, accuracy (% correctly classified) was high and comparable either using optimal or guidelines' thresholds (2000 AU in men, 1200 AU in women). However, accuracy was lower in Asian women vs. Caucasian women (76–78% vs. 94–95%; P  < 0.001). Accuracy of AVC-density (476 AU/cm2 in men and 292 AU/cm2 in women) was comparable to absolute AVC in Caucasians (91% vs. 91%, respectively, P  = 0.74), but higher than absolute AVC in Asians (87% vs. 81%, P  < 0.001). There was no interaction between AVC/AVC-density and ethnicity (all P  > 0.41) with regards to AS haemodynamic severity. Conclusion AVC thresholds defining severe AS are comparable in Asian and Caucasian populations, and similar to those proposed in the guidelines. However, accuracy of AVC to identify severe AS in Asians (especially women) is sub-optimal. Therefore, the use of AVC-density is preferable in Asians. [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]

Purpose: Ischemia/reperfusion injury remains an untreated clinical problem in patients with acute myocardial infarction (AMI) despite significant advances in emergent revascularization through percutaneous coronary intervention (PCI). Pharmacological intervention for infarct size reduction is unavailable. We have identified that the medications milrinone and esmolol, when administered together at the beginning of the reperfusion, significantly decrease infarct size via reducing reperfusion injury in an experimental model. The present study tested the safety of combination therapy of milrinone and esmolol (M + E) in patients with AMI. Methods: Sixteen subjects with AMI requiring PCI were consecutively recruited. M + E was intravenously infused simultaneously for 10 min started at 5 min before anticipated angioplasty balloon inflation. Another 16 consecutively recruited AMI patients requiring PCI served as a placebo arm treated per routine clinical protocol. Blood pressure (BP) and heart rate (HR) were monitored continuously during PCI. Results: M + E combination therapy resulted in a trend of non-significant reduction in BP compared with a control group. There was a modest but significant increase in HR at the later phase of M + E infusion compared with a control group. No significant cardiac arrhythmia was induced during M + E infusion. Conclusions: The combination therapy with M + E produces a minimal change in hemodynamics and appears safe as an adjunctive therapy to PCI in AMI patients. Further studies are warranted. [ABSTRACT FROM AUTHOR]

Abstract: Background: Patients with Eisenmenger syndrome (ES) have a decreased exercise capacity and poor quality of life (QoL). While patients may survive to middle adulthood, the burden of disease is disabling. Sildenafil seems to improve exercise tolerance and hemodynamics, but there is no data to date on its impact on QoL. Methods: Eisenmenger patients in New York Heart Association (NYHA) class III were recruited in a prospective study of efficacy and safety of oral sildenafil. The QoL endpoint was assessed using a disease-specific questionnaire (CAMPHOR). Exercise capacity was assessed by means of six minute walk test (6MWT). All patients underwent comprehensive assessment at baseline and after 3months of treatment. Results: Twelve patients (mean age was 34.3±10.2, 83% female) with various cardiac anatomies were recruited. No major adverse events during the follow-up or significant drop in resting oxygen saturation were recorded. After 3months of oral sildenafil therapy, all patients improved to NYHA II with a concomitant improvement in 6MWT distance (347.3±80.7 to 392.5±82.0m, p =0.002). All components of the CAMPHOR score, relating to symptoms, activity and QoL, improved significantly resulting in substantial improvement in the total CAMPHOR score (27.6±10.5 to 15.8±10.4, p =0.002). Conclusions: Three months of sildenafil therapy in adults with ES was well tolerated and associated with significant improvement in the QoL CAMPHOR questionnaire and in NYHA class and exercise capacity. Larger studies are warranted to assess long term efficacy of oral sildenafil and potential impact on survival. [Copyright &y& Elsevier]

Objectives: We evaluated transcatheter aortic valve implantation (TAVI) in high-risk patients with bicuspid aortic valve (BAV) stenosis. Background: TAVI shows promise in the treatment of severe stenosis of triscupid aortic valves, especially in high-risk patients. However, BAV stenosis has been considered a contraindication to TAVI. Methods: Eleven patients (age 52 to 90 years) with symptomatic severe BAV stenosis underwent TAVI at 3 Canadian tertiary hospitals between May 2006 and April 2010. All patients were considered high risk for surgical aortic valve replacement. Edwards-SAPIEN transcatheter heart valves (Edwards Lifesciences, Inc., Irvine, California) were used. Transfemoral or transapical access was selected, depending on the adequacy of femoral access. Results: Access was transfemoral in 7 patients and transapical in 4 patients. There were no intraprocedural complications. Significant symptomatic and hemodynamic improvement was observed in 10 of 11 patients. Baseline aortic valve area of 0.65 ± 0.17 cm2 and mean transaortic pressure gradient of 41 ± 22.4 mm Hg were improved to 1.45 ± 0.3 cm2 and 13.4 ± 5.7 mm Hg, respectively. Two patients had moderate perivalvular leaks. At the 30-day follow-up there were 2 deaths due to multisystem failure in 2 transapical patients. In 1 patient an undersized, suboptimally positioned, unstable valve required late conversion to open surgery. Conclusions: TAVI in selected high-risk patients with severe BAV stenosis can be successfully performed with acceptable clinical outcomes but will require further evaluation. [ABSTRACT FROM AUTHOR]