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Clinical outcomes for intermediate or high-risk pulmonary emboli (PE) remain sub-optimal, with limited improvements in survival for the past 15 years. Anticoagulation alone results in slow thrombus resolution, persistent right ventricular (RV) dysfunction, patients remaining at risk of haemodynamic decompensation and increased likelihood of incomplete recovery. Thrombolysis elevates risk of major bleeding and is thus reserved for high-risk PE. Thus, a huge clinical need exists for an effective technique to restore pulmonary perfusion with minimal risk and avoidance of lytic therapy. In 2021, large bore suction thrombectomy (ST) was introduced in Asia for the first time and this study assessed the feasibility and short-term outcomes of Asian patients undergoing ST for acute PE. 40 consecutive patients (58% male, mean age of 58.3 ± 16.6 years) with intermediate (87.5%) or high-risk PE (12.5%) were enrolled in this prospective registry. 20% had prior VTE, 42.5% had contraindications to thrombolysis, and 10% failed to respond to thrombolysis. PE was idiopathic in 40%, associated with active cancer in 15% and post-operative status in 12.5%. Procedural time was 124 ± 30 min. Emboli were aspirated in all patients without the need for thrombolytics, resulting in a 21.4% reduction in mean pulmonary arterial pressures and 123% increase TASPE-PASP ratio, a prognostic measure of RV-arterial coupling. (both p < 0.001) Procedural complications were 5% and 87.5% patients survived to discharge without symptomatic VTE recurrence during 184 days of mean follow-up. ST affords an effective reperfusion option for PE without thrombolytics, normalises RV overload and provides excellent short-term clinical outcomes. Key points: Large bore suction thrombectomy is an effective minimally invasive reperfusion therapy for patients with intermediate or high-risk pulmonary embolism (PE), without the use of thrombolytics. Significant reductions in mean pulmonary arterial pressures and heart rates were achieved, resulting in normalisation of right ventricular (RV) strain, size and improvement in RV-pulmonary arterial coupling and stroke volumes. 95% of PE patients who did not require cardiopulmonary resuscitation, survived to discharge without VTE recurrence during 184 days of mean follow-up. Ongoing multi-centre randomized controlled trials comparing suction thrombectomy to routine care will confirm the benefits of early catheter-based reperfusion therapy for PE. [ABSTRACT FROM AUTHOR]

Left ventricular thrombus (LVT) is a common complication of acute myocardial infarction and is associated with morbidity from embolic complications. Predicting which patients will develop death or persistent LVT despite anticoagulation may help clinicians identify high-risk patients. We developed a random forest (RF) model that predicts death or persistent LVT and evaluated its performance. This was a single-center retrospective cohort study in an academic tertiary center. We included 244 patients with LVT in our study. Patients who did not receive anticoagulation (n = 8) or had unknown (n = 31) outcomes were excluded. The primary outcome was a composite outcome of death, recurrent LVT and persistent LVT. We selected a total of 31 predictors collected at the point of LVT diagnosis based on clinical relevance. We compared conventional regularized logistic regression with the RF algorithm. There were 156 patients who had resolution of LVT and 88 patients who experienced the composite outcome. The RF model achieved better performance and had an AUROC of 0.700 (95% CI 0.553–0.863) on a validation dataset. The most important predictors for the composite outcome were receiving a revascularization procedure, lower visual ejection fraction (EF), higher creatinine, global wall motion abnormality, higher prothrombin time, higher body mass index, higher activated partial thromboplastin time, older age, lower lymphocyte count and higher neutrophil count. The RF model accurately identified patients with post-AMI LVT who developed the composite outcome. Further studies are needed to validate its use in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: To develop a consensus statement for left atrial appendage occlusion (LAAO) in Asian-Pacific patients with non-valvular atrial fibrillation (NVAF) at risk of ischemic stroke. The need for such a region-specific consensus was indicated by the relative paucity of clinical evidence for LAAO and oral anticoagulation therapy obtained in Asian-Pacific populations and the specific stroke and bleeding characteristics of this population. Methods: Consensus was developed by discussion and evaluation of available evidence and expert opinions during a 2-day meeting attended by clinical experts from the Asian-Pacific regions. Results: The consensus statement arrived at provides recommendations based on available evidence and expert opinions regarding LAAO in Asian-Pacific patients. Gaps in the evidence and other areas requiring further research were identified. Conclusion: LAAO is an alternative device-based therapy in carefully selected patients with NVAF at risk of ischemic stroke. However, evidence for LAAO is primarily obtained from Caucasian populations, and data on LAAO in Asian-Pacific patients are scarce. While the present consensus statement addresses several therapy-related aspects based on careful interpretation of available evidence and expert opinions, other areas require additional evidence derived from Asian-Pacific populations. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to develop a simple and effective percutaneous approach to create tricuspid regurgitation in swine. Methods: Eleven pigs (71.68 ± 7.70 kg, 3 male) were involved in this study. A grasping forceps was introduced into the right ventricle through a steerable sheath under fluoroscopic guidance and used to disrupt the tricuspid valve apparatus by avulsing leaflet or chordae tendineae repeatedly. Transthoracic echocardiography and right ventricular angiography were used to evaluate the degree of tricuspid regurgitation created. Results: Ten of the 11 pigs (90.91%) achieved severe tricuspid regurgitation and 1 (9.09%) obtained moderate tricuspid regurgitation immediately after the procedure. Heart rate of the pigs significantly increased immediately after tricuspid regurgitation creation compared to baseline (88.64 ± 23.24 vs. 76.00 ± 15.30 bpm, P = 0.02), but recovered to normal level at one month follow-up (77.09 ± 11.97 bpm, P = 0.85). The right atrium, tricuspid valve annulus, and right ventricle dilated obviously one month after tricuspid regurgitation creation (dimension changes: 3.01 ± 0.35 vs. 3.56 ± 0.40 cm, P = 0.02; 2.92 ± 0.36 vs. 3.37 ± 0.39 cm, P = 0.01; 3.06 ± 0.42 vs. 3.60 ± 0.47 cm, P = 0.03 respectively). Autopsy findings showed that rupture of leaflet and/or chordae tendineae finally led to the tricuspid regurgitation. Conclusions: Severe tricuspid regurgitation can be created by a simple and effective percutaneous approach with a grasping forceps in swine model and right heart dilation can be observed consistently at one-month follow-up. This model will be valuable in pre-clinical studies for developing new tricuspid valve repair or replacement technique to treat severe tricuspid regurgitation. [ABSTRACT FROM AUTHOR]

In patients with significant aortic stenosis (AS), the prognostic effect of the increase in left ventricular mass (LVM) in relation to one's hemodynamic load has been described. Inappropriately high LVM has been shown to predict adverse cardiovascular events. However, little is known about the prognostic impact of inadequately low LVM (i-lowLVM) in patients with significant AS. I-lowLVM was defined as the measured LVM < 73% of the predicted LVM based on sex, stroke work and height from the reference adult population, used in previous established studies. For outcome analysis, the end-point was defined as all-cause mortality, aortic valve replacement and/or admission for congestive heart failure. Kaplan-Meier curves and multivariable Cox regression models were constructed to compare outcomes on follow-up. During the follow-up (4.5 ± 4.1 years), 132 patients (11.1%) had i-lowLVM, 868 (73.1%) had adequate-LVM, 188 (15.8%) had inappropriately high LVM. Outcome analysis only included patients with i-lowLVM and adequate-LVM (N = 1000). An adverse composite event occurred in 41.7% of the i-lowLVM group and 52.4% of the adequate-LVM group (p = 0.021). Event-free survival in patients with i-lowLVM and appropriate-LVM was 76% versus 68% at 2-year, 55% versus 46% at 4-year, 33% versus 27% at 6-year, 20% versus 17% at 8-year, and 17% versus 11% at 10-year follow-up, respectively (p < 0.001). Cox analysis revealed that i-lowLVM was independently associated with lower composite adverse outcome (HR 0.624, 95% CI 0.460-0.846, p = 0.002) after adjusting for sex, age, ejection fraction, ischemic heart disease, diabetes and transaortic valve mean gradient. In the separate Cox subanalyses, the presence of i-lowLVM remained a predictor of lower composite adverse outcome in the severe AS subgroup (HR 0.587, 95% CI 0.396-0.870, p = 0.008), and the LVH subgroup (HR 0.574, 95% CI 0.401-0.824, p = 0.003) after adjusting for confounders. I-lowLVM despite significant AS may represent a distinct group that is associated with improved survival outcomes independent of other prognostic covariates. [ABSTRACT FROM AUTHOR]

Inconsistencies in grading of aortic stenosis (AS) severity have been reported. However, it remains to be studied in an Asian population. We investigated consistency of grading AS severity at various left ventricular outflow tract diameter (LVOTd) categories, and postulated alternative cut-offs for more consistent grading of AS severity. Consecutive Asian patients (n = 350) with index echocardiographic diagnosis of severe AS were divided them into three groups based on LVOTd: 'small' (< 20 mm), 'average' (20-22 mm) and 'large' (> 22 mm). In each group, the consistency of flow-dependent (transaortic mean pressure gradient (MG)) and flow-independent parameters (AVA) were used for classification of AS severity. Of 350 patients, 51.7% had small LVOTd, while 30.8% and 17.5% had average and large LVOTd respectively. Consistent grading by LVOTd based on AVA and MG, was seen in 33.7% of patients with small, 47.6% with average, 57.7% with large LVOTd. When an AVA cut-off of 0.9 cm2 was used, consistent grading improved to 38.0% in small, 56.5% in average and 70.0% in large LVOTd. At an AVA cut-off of 0.8 cm2, there was further incremental improvement in the small LVOTd group to 54.1% (p < 0.05). In conclusion, current severe AS guidelines are most inconsistent with those in the small LVOTd group. With majority of the study's Asian population having small LVOTd, this raises concerns that current AS guidelines may overestimate the severity of AS in the Asian cohort. Improved consistency in echocardiographic grading may be attained with a lower AVA cut-off in this Asian cohort. [ABSTRACT FROM AUTHOR]

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 cm2) were analysed retrospectively. All patients had preserved ejection fraction (LVEF  ≥ 50%, n = 645), and were divided into PLF (stroke volume index, SVI < 35 mL/m2) 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. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke (AIS) is a feared complication in post-acute myocardial infarction (AMI) patients who develop left ventricular (LV) thrombus. There is limited data available on the incidence of stroke in this population, and characterisation of stroke subtypes has not been previously reported. Our study aims to evaluate the incidence of AIS in post-AMI patients with LV thrombus and to characterise the pattern of stroke subtypes. We screened 5829 patients with echocardiogram reports containing the "thrombus" keyword from August 2006 to September 2017. AIS that occurred after LV thrombosis was captured and relevant clinical data was collected. We identified 289 post-AMI patients with acute LV thrombus formation. Mean age was 59.3 ± 13.4 years. AIS occurred in 34 patients (11.8%), median duration of 20.5 days (IQR = 5.5–671.8) after LV thrombosis. Despite initial thrombus resolution, nine (5.2%) encountered AIS subsequently. Cardioembolic stroke subtype was identified in 76.5% of AIS, whilst 14.7% was small vessel disease and 8.8% was of large artery atherosclerosis subtype. Presence of thrombus protrusion (HR 3.04, 95% CI 1.25–7.41, p = 0.01), failure of initial thrombus resolution (HR 3.03, 95% CI 1.23–7.45, p = 0.02) and thrombus recurrence (HR 4.20, 95% CI 1.46–12.11, p < 0.01) were significant independent predictors for stroke. Incidence of AIS in this Asian population of post-AMI patients with LV thrombus was 11.8%. Duration of anticoagulation may need to be individualised for patients with higher risk for stroke occurrence after LV thrombosis. [ABSTRACT FROM AUTHOR]

The increased understanding of right heart diseases has led to more aggressive interventions to manage functional tricuspid regurgitation (FTR). In some cases of FTR, prosthetic valve replacement is typically considered when concomitant organic components or significant geometrical distortions are involved in the pathology of the tricuspid valve. However, little is known of the performance of current devices in the right heart circulation. In this study, a novel in vitro mock circulatory system that incorporated a realistic tricuspid valve apparatus in a patient-specific silicon right ventricle (RV) was designed and fabricated. The system was calibrated to emulate severe FTR, enabling the investigation of RV hemodynamics in pre- and post-implantation of tri-leaflet tissue implant and bi-leaflet mechanical implant. 2D particle imaging velocimetry was performed to visualize flow and quantify relevant hemodynamic parameters. While our results showed all prosthetic implants improved cardiac output, these implants also subjected the RV to increased turbulence level. Our study also revealed that the implants did not create the optimal behavior of fluid transfer in the RV as we expected. Among the implants tested, tissue implant created the most dominant vortices, which persisted throughout diastole; its observed strong negative vortex could lead to increase energy expenditure due to undesired fluid direction. In contrast, both native valve and mechanical implant had both weaker vortex formation as well as more significant vortex dissipation. Interestingly, the vortex dissipation of native valve was associated with streamlined flow pattern that tended towards the pulmonary outlet, while the mechanical implant generated more regions of flow stagnation within the RV. These findings heighten the imperative to improve designs of current heart valves to be used in the right circulation. [ABSTRACT FROM AUTHOR]

A cardiocerebral ischemic attack (CCI) or a concurrent acute ischemic stroke (AIS) and myocardial infarction (AMI) is a severe event with no clear recommendations for ideal management because of the rarity of the scenario. The narrow time window for treatment and complexity of the treatment decision puts immense pressure on the treating physician. We evaluated this challenging situation at our tertiary center. Using our prospective stroke database out of a total of 555 patients with acute ischemic stroke between 2009 and 2014, we identified five consecutive cases with CCI (incidence 0.009%). Demography, risk factor characteristics, vascular occlusions and treatment approach were recorded. Good functional outcome was defined by the modified Rankin scale (mRS) score of 0-2 points. Out of five patients, AIS was treated with endovascular treatment in three cases, while two were treated with intravenous thrombolysis only. One out of three patients had embolectomy of the brain performed prior to the coronary intervention, while the other two patients underwent coronary intervention first. One patient developed sudden cardiac arrest on day-2 and passed away. CCI is an uncommon and devastating clinical scenario, further research is needed for the ideal management strategy that provides the best outcomes. However, the rarity of the disease does not lend itself to the conduct of a trial easily. We have proposed a considered treatment algorithm based on the current literature and our experience. [ABSTRACT FROM AUTHOR]

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 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. [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]

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. [ABSTRACT FROM AUTHOR]