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Aims Inspiratory muscle training (IMT) can increase the strength or endurance of the diaphragm and accessory muscles of inspiration, yet there is no evidence that endorses the role of IMT in patients of transcatheter aortic valve replacement (TAVR). This study for the first time tested the effects of IMT plus usual cardiac rehabilitation (CR) function in patients after TAVR. Methods and results A double-blinded, randomized controlled, single-centre clinical trial was undertaken. Participants who had a confirmed diagnosis of valve heart disease and were clinically stable after TAVR were recruited and received a CR programme during the hospital stay. A total of 96 patients were recruited and randomly assigned to the IMT + CR group (n = 48) or the CR group (n = 48) in a 1:1 ratio. The group difference in the primary outcome, the 6-min walk distance at the discharge of the hospital, significantly favoured the IMT + CR group (mean difference −33.52, 95% CI: −64.42 to −2.62, P = 0.034). The significant difference was maintained at the 1-month and 3-month follow-ups (mean difference: 41.51, 95% CI: 1.82–81.21, P = 0.041). In addition, the mean hospital stays of subjects in the IMT + CR group was 11 days, which was significantly shorter than the 12.5 days in the CR group (P = 0.016). Sensitivity analysis using per-protocol analysis supported these findings. No adverse treatment-related events were reported. Conclusion Compared with usual CR, IMT plus CR can effectively improve exercise endurance, pulmonary ventilation function, and inspiratory muscle strength in patients after TAVR and shorten the length of hospital stay.

In this paper, we present the fabrication and performance of a linear-motor type flux pump with a pumped current larger than 640 A. This high-temperature superconducting (HTS) flux pump can be used for magnetic resonance imaging (MRI) magnets and HTS electric machines. We use the flux pump to charge 10 superconducting closed-loops, and show the tested results of pumping current under different applied frequencies and magnetic field amplitudes. This flux pump device can output direct current larger than 640 A at 77 K. The output of this flux pump equals to a DC power source with low output voltage and high output current. Comparing with the traditional power supply of the same rated current, the size of this HTS flux pump is much smaller, while it also eliminates the harmful metal current leads that cause heat leakage. We show that, by increasing the length of the travelling wave region of this flux pump, there is no limit to the output of the current output, which can reasonably reach the kilo-ampere level. The purpose of this paper is to test the reliability of the methodology for the large current HTS flux pump.

The linear-motor type flux pump is a wireless DC power source for high-temperature superconducting coils, which is compact in size, efficient in energy use, fast in output control, etc. It consists of three major parts: DC windings, phase windings and iron circuit, which generates a DC-bias AC travelling wave in its airgap. In theory, there are three controllable parameters such as DC-bias field, amplitude of the AC travelling wave, and the field frequency (travelling speed). By changing those parameters, we change the applied fields and its DC output current into superconducting coils. For studying the impact of those parameters on its DC output, this paper uses a fixed step algorithm to collect the current charging data, by automatically controlling the flux pump device, and then establishes an output database. By using this algorithm, we have searched out the maximum pumped current and analyzed the impact of the three parameters. We have also found out that, in order to get maximum current output, the value of the DC-bias field should be close to the amplitude of AC magnetic field.

Near-infrared spectroscopy (NIRS) is a non-invasive approach that measures cerebral regional oxygen saturation (rScOWe searched electronic bibliographic databases (PubMed, The Cochrane Library and Embase) and screened the studies that met the inclusion criteria. We included cross-sectional studies of CHD pediatric patients in the perioperative period receiving both tests for NIRS rScOThere was no significant difference in Cohen's d between rScOThe rScO

BACKGROUND: It is unknown whether there are differences in coronary access after transcatheter aortic valve replacement (TAVR) between bicuspid and tricuspid anatomy. AIMS: Our aim was to investigate coronary access after TAVR using a self-expanding transcatheter heart valve (THV) in bicuspid versus tricuspid aortic valves (BAV vs TAV), based on CT simulation. METHODS: A total of 86 type 0 BAV, 70 type 1 BAV, and 132 TAV patients were included. If the coronary ostium faced the sealed parts of the THV or the tilted-up native leaflet (NL), this was defined as THV- or NL-related challenging coronary access, respectively. If coaxial engagement was not allowed due to interference from the unwrapped frame, THV-related complex coronary access was defined. RESULTS: The incidence of THV-related challenging coronary access was 21.2% for the left coronary artery (LCA) and 17.7% for the right coronary artery (RCA), and type 0 BAV patients encountered fewer THV-related challenging LCA access than their TAV counterparts (OR 0.42, 95% CI: 0.20-0.89). NL-related challenging coronary access was observed in 3.1% for LCA and 1.4% for RCA, and THV-related complex coronary access was identified in 5.9% for LCA and 17.0% for RCA; however, no significant differences were found among groups. The proportion of optimal fluoroscopic viewing angles suitable for guiding LCA engagement was similar among groups (64.0% vs 70.0% vs 62.1%), but those suitable for guiding RCA engagement were significantly higher in the type 0 BAV group (31.4% vs 4.3% vs 9.1%). CONCLUSIONS: Coronary access may be challenging or complex in a significant proportion of both BAV and TAV patients after TAVR. Type 0 BAV anatomy may be more favourable for post-TAVR coronary access.

Primary percutaneous coronary intervention (PPCI), the preferred reperfusion strategy for all acute ST-segment elevation myocardial infarction (STEMI) patients, is not universally available in clinical practice. Pharmacoinvasive strategy has been proposed as a therapeutic option in patients with STEMI when timely PPCI is not feasible. However, pharmacoinvasive strategy has potential delay between clinical patency and complete myocardial perfusion. The optimal reperfusion strategy for STEMI patients with anticipated PPCI delay according to current practice is uncertain. OPTIMAL-REPERFUSION is an investigator-initiated, prospective, multicenter, randomized, open-label, superiority trial with blinded evaluation of outcomes. A total of 632 STEMI patients presenting within 6 hours after symptom onset and with an expected time of first medical contact to percutaneous coronary intervention (PCI) ≥120 minute will be randomized to a reduced-dose facilitated PCI strategy (reduced-dose fibrinolysis combined with simultaneous transfer for immediate invasive therapy with a time interval between fibrinolysis to PCI

Objectives. To investigate the metabolic profile in patients with aortic stenosis (AS) after transcatheter aortic valve replacement (TAVR) and explore the potential biomarkers to predict prognosis after TAVR based on metabolomics. Methods and Results. Fifty-nine consecutive AS patients were prospectively recruited. Blood samples from the ascending aorta, coronary sinus, and peripheral vein at before and after TAVR were collected, respectively. Liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry were performed to analyze the metabolic profile before and after TAVR. Influential metabolites were identified by integrating the univariate test, multivariate analysis, and weighted gene coexpression network analysis (WGCNA) algorithm. PLS-DA analysis revealed a significant extremely early (within 30 minutes after TAVR) alterations of metabolites in the ascending aorta, coronary sinus, and peripheral vein. The early (within 7 days after TAVR) changed metabolites in the peripheral vein were involved in purine metabolism, primary bile acid biosynthesis, glycerolipid metabolism, amino sugar and nucleotide sugar metabolism, one carbon pool by folate and alanine, and the aspartate and glutamate metabolism pathway. We used volcano plots to find that the cardiac-specific changed metabolites were enriched to the sphingolipid metabolism pathway after TAVR. Besides, WGCNA algorithm was performed to reveal that arginine and proline metabolites could reflect left ventricle regression to some extent. Conclusion. This is the first study to reveal systemic and cardiac metabolites changed significantly in patients with AS after TAVR. Some altered metabolites involved in the arginine and proline metabolism pathway in the peripheral vein could predict left ventricle regression, which merited further study.

Objectives We evaluated the safety and usefulness of preparatory anatomical reshaping with a geometric hourglass-shaped balloon to optimize transcatheter aortic valve replacement (TAVR) outcomes in bicuspid aortic valve (BAV) stenosis. Background TAVR has been increasingly performed for BAV stenosis; however, technical challenges remain. Procedural results are suboptimal given unfavorable valvular anatomies. Methods Eligible patients with BAV stenosis were enrolled to undergo aortic valve predilatation with the hourglass-shaped TAV8 balloon before TAVR using the self-expandable Venus A-Valve. Procedural details and outcomes were compared to a sequential group of patients with BAV who underwent TAVR with the same device following preparatory dilatation using a cylindrical balloon. Results A total of 22 patients were enrolled in the TAV8 group and 53 were included in the control group. Valve downsizing was less common in the TAV8 group (36.4 vs. 67.9%; p = .012). Stable valve release and optimal implant depth were consistently achieved in the TAV8 group with no requirement for a second valve (0 vs. 17.0%; p = .039) and with higher device success rates (100.0 vs 77.4%; p = .014). Residual aortic regurgitation graded as ≥mild was less common in the TAV8 group (13.6 vs 45.3%; p = .009). Mortality was similar (0 vs. 3.8%; p = 1); no major/disabling stroke or conversion to open-heart surgery was seen in either group within 30 days. Conclusions Compared with standard cylindrical balloon valvuloplasty, preparatory reshaping with the hourglass-shaped balloon before self-expandable TAVR in BAV was associated with significantly better procedural results and may encourage more promising outcomes.

Highlights • Developed a novel monogram model for long-term diabetic risk prediction. • The novel nomogram is a practical screening model. • The model may help clinicians to identify individuals at high risk of diabetes., The prevalence of diabetes is increasing rapidly and becoming a major public health issue worldwide. We aimed to develop a novel nomogram model for long-term diabetic risk prediction in a Chinese population. A prospective cohort study was performed on 687 nondiabetic individuals who underwent routine physical examination in 1992 and 2007. Using the least absolute shrinkage and selection operator model to optimize feature selection. Multiple Cox regression analysis was performed, and a simple nomogram was constructed. The area under receiver operating characteristic curve (AUC) and calibration plot were conducted to assess the predictive accuracy of the model. The model was subjected to bootstrap internal validation. Of the 687 participants without diabetes at baseline, 74 developed diabetes during the follow-up time. This simple nomogram model was constructed by family history of diabetes, height, waist circumference, triglycerides, fasting plasma glucose and white blood cell count. The AUCs were 0.812 (95% CI: 0.729–0.895) and 0.794 (95% CI: 0.734–0.854) for 10-year and 15-year diabetic risk. The bootstrap corrected c-index was 0.771 (95% CI: 0.721–0.821). The calibration plot also achieved good agreement between observational and actual diabetic incidence. The stratification into different risk groups by optimal cut-off value of 12.8 allowed significant distinction between cumulative diabetic incidence curves in the whole cohort and several subgroups. We established and internally validated a novel nomogram which can provide individual diabetic risk prediction for Chinese population and this practical screening model may help clinicians to identify individuals at high risk of diabetes.

Background A new metabolic health (MH) definition was proposed recently. We aimed to investigate the association between the new MH definition and all-cause mortality (ACM) in a nonobese Chinese population. Methods A total of 1157 participants with 15-year of follow-up were included for the present analysis. The association between MH and ACM were analyzed by Cox regression models with overlap weighting according to propensity score (PS) as primary analysis. Results At baseline, 920 (79.5%) participants were categorized as MH and 237 (20.5%) participants were categorized as metabolic unhealth (MUH) by this new definition. During follow-up, ACM occurred in 30 participants with mortality rate at 1.85% in MH group and 5.49% in MUH group, respectively. In the crude sample, Kaplan-Meier (K-M) analysis demonstrated a significantly lower ACM in MH group when compared to MUH group (log-rank p = 0.002). However, in multivariable Cox analysis, MH was not significantly associated with reduced ACM when compared to MUH with HR at 0.92 (95% CI: 0.32-2.64, p = 0.875). Moreover, overlap weighting-adjusted K-M analysis showed that the cumulative incidence of ACM was not significantly different between MH and MUH groups (adjusted p = 0.589). In the primary multivariable Cox analysis with overlap weighting, the HR for ACM was 0.70 (95% CI: 0.24-2.06, p = 0.519) in MH group in reference to MUH group. Additional PS analyses yielded similar results. Conclusion The new MH definition was not significantly associated with ACM in non-obese Chinese people. Further investigations are needed.

To investigate the predictive values of the new metabolic health (MH) definition for future diabetes in a nonobese Chinese population, compared with the MH definition from metabolic syndrome (MetS).The data were collected in 1992 and then again in 2007 from the same group of 653 participants. The risk assessment of the new MH definition and the MH definition from MetS for future diabetes was performed by Cox regression analysis with overlap weighting as the primary analysis.During the follow-up, 62 participants were diagnosed with diabetes. In the primary analysis with overlap weighting, there was no significant association between new MH and diabetes (HR: 1.12; 95% CI: 0.45-2.78, p = 0.803); conversely, based on the MH definition from MetS, the participants with MH were less likely to have had diabetes than the participants with MUHs (HR: 0.41; 95% CI: 0.22-0.78, p = 0.007). Furthermore, other analysis methods also confirmed the reproducibility of abovementioned results. In addition, sensitivity analysis excluding participants with prediabetes also demonstrated similar results with the primary analysis.In contrast to the previous MH definition from MetS, the new MH definition was not a reliable predictor for future diabetes in the nonobese Chinese population.

Background With the expanded utilization of transcatheter aortic valve implantation (TAVI) to younger and lower surgical risk patients with severe aortic stenosis (AS), optimal medical therapy after TAVI procedure has become the main concern. Renin-angiotensin system inhibitors (RASi) are widely utilized in the area of cardiovascular disease including heart failure and myocardial infarction and revealed the ability to reverse left ventricular (LV) remodeling. Interests have, thus, been drawn in investigating whether the prescription of RASi after the TAVI procedure can prevent or reverse cardiac remodeling and improve long-term clinical outcomes. No recommendation regarding the prescription of RASi after TAVI is proposed yet due to the lack of evidence from randomized controlled trials, especially in the Chinese population. We, therefore, designed this randomized controlled trial to explore the effect of adding fosinopril to standard care in patients who underwent a successful TAVI procedure on the LV remodeling. Methods A total of 200 post-TAVI patients from seven academic hospitals across China will be recruited and randomized with a ratio of 1:1 to receive standard care or standard care plus fosinopril. Follow-up visits will take place at 30 days, 3 months, 6 months, 12 months, and 24 months from randomization to assess the clinical symptoms, any adverse events, cardiac function, and quality of life. Cardiac magnetic resonance will be performed at baseline and repeated at the 24-month follow-up visit to assess LV remodeling. Discussion This study will provide evidence regarding medical therapy for AS patients who underwent TAVI and filling the gap in the Chinese population. Trial registration Chinese Clinical Trial Registry ChiCTR2100042266. Registered on 17 January 2021

The effects of intravenous lidocaine on the refractory periods of the atrium, AV node and right ventricular myocardium were studied using His bundle recordings and the extrastimulus technique with and without atrial and ventricular pacing The drug was administered in an intravenous bolus dose of 1 mg/Kg followed by an infusion of 100 micrograms/Kg/min The AH, HV intervals and resting sinus cycle length as well as functional and effective refractory periods of atrium, AV node and right ventricle were measured before and 5 min afrer bolus injection of lidocaine Neither of the refractory periods nor AH and HV intervals changed significantly following administration of lidocaine The result of this first study in children is in agreement with previous reports of the effects of lidocaine on the cardiac conduction system in adults

The authors sought to better understand the stent geometry of the Lotus valve after transcatheter aortic valve replacement (TAVR) and its potential implications for valve size selection.The authors hypothesized that the greatest interference between the frame and aortic valvar complex occurs across the aortic valve leaflets.The authors retrospectively analyzed the multidetector computed tomography (MDCT) scans of 32 consecutive patients undergoing Lotus valve (Boston Scientific, Natick, Massachusetts) implantation. The prosthesis cross section was analyzed at 3-mm increments along its length. The plane where the frame had the smallest area was defined as the waist. The corresponding plane of the waist on pre-procedural MDCT was identified by surrounding structures such as calcium deposits, commissural fusion, and commissural gaps, and was referred to as the supra-annulus. The spline of the supra-annulus was circumscribed with reference to the post-implant stent geometry at the waist.The waist was 5.8 ± 1.7 mm higher than the native annulus on post-procedural MDCT. The waist had a nearly 2-fold larger compression rate than the stent at the native annulus level (36.3 ± 10.4% vs. 18.9 ± 9.6%; p 0.01), irrespective of valve morphologies. The supra-annulus was 5.9 ± 1.6 mm higher than the annulus on pre-procedural MDCT. Patients had an approximately 17% decrease in area from the annulus to the supra-annulus (18.3 ± 4.4% for bicuspid morphology and 16.0 ± 3.5% for tricuspid morphology).Major interference between the implanted prosthesis and anatomy occurred at a level above the annulus. The decrease in area from the annulus to supra-annulus may explain the feasibility of implanting a smaller valve than that suggested by traditional annular measurements.

We sought to identify the impact of transcatheter aortic valve implantation (TAVI) on changes of fractional flow reserve computed tomography (FFRCT) values and the associated clinical impact. A retrospective analysis was done with CT obtained pre-TAVI, prior to hospital discharge and at 1-year follow-up, which provided imaging sources for the calculation of FFRCT values based on an online platform. A total of 190 patients were enrolled. Patients with pre-procedural FFRCT value > 0.80 (i.e., negative) and ≤ 0.80 (i.e., positive) demonstrated a significantly opposite change in the value after TAVI (0.8798 vs. 0.8718, p < 0.001 and 0.7634 vs. 0.8222, p < 0.001, respectively). The history of coronary artery disease (CAD) was identified as an independent predictor for FFRCT changing from negative to positive after TAVI (odds ratio [OR] 2.927, 95% confidence interval [CI] 1.130–7.587, p = 0.027), with lesions more severely stenosed (OR 1.039, 95% CI 1.003–1.076, p = 0.034) and in left anterior descending coronary artery (LAD) (OR 3.939, 95% CI 1.060–14.637, p = 0.041) being prone to change. TAVI directly brings improvement in FFRCT values in patients with compromised coronary flow. Patients with a history of CAD, especially with lesions more severely stenosed and in LAD, were under risk of FFRCT changing from negative to positive after TAVI. •The effect of TAVI on coronary hemodynamics might be influenced by different ischemic severity and coronary territories reflected by FFRCT values. •As different FFRCT variations did not impact outcomes of TAVI patients, AS, but not coronary issues, may be the primary problem to affect, which needs further validation.

Superconducting flux pumps can provide large currents to the superconducting magnets without contact and reduce the heating loss of mental current leads between cryogenic environment and room environment, which will reduce cooling losses and improve the working efficiency of high-temperature superconducting (HTS) motors. It can be used as a DC power resource for many applications. In this paper, the experimental platform of synchronous motor with a linear-motor type flux pump, which has been under construction, and the no-insulation (NI) racetrack coil manufactured by our laboratory winding machine with YBCO tape have been designed. Based on the linear-motor type flux pump that has been proposed in our laboratory, we have miniaturized it in volume and used the linear-motor type flux pump as a DC power supply to measure the magnetization of NI racetrack coil without contact. The charging experiment of the linear-motor type flux pump using the constructed YBCO racetrack coil was conducted at 77K. The experimental results will optimize the HTS flux pump applied to the brushless HTS synchronous motor.

This paper presents the fabrication of a self-adaptive linear-motor type flux pump for dedicated magnetic resonance imaging (MRI) magnets. This kind of high temperature superconducting (HTS) flux pump could be used to magnetize the second generation (2G) HTS double-pancake coil (DPC). We plan to use this flux pump to charge the 10 no-insulation (NI) DPCs. The structure design and operational principle have been described. We have carried out preliminary experiments to measure the magnetic field at different positions of the flux pump. Our design goal is to make the current provided by this flux pump comparable to conventional superconducting DC power supplies. Compared with the traditional power supply method, using this flux pump eliminates the current leads that cause heat leakage. With further optimization and design, this flux pump can reach the kiloampere level and is expected to be applied to superconducting dedicated MRI magnets.

Background: The initial mechanism of COVID-19 is the binding of the virus to ACE2. Since the heart and the vessels also express ACE2, they both could become targets of the virus. However, cardiac performance of mild and severe patients may be different, requested individualized treatment. The aim of this study is to explore the global and segmental myocardial performance of the severe and mild COVID-19 patients.Methods: 45 patients with COVID-19 infection were included in this study. The clinical history, laboratory test and standard and strain echocardiography were performed at admission. Results: 1. All patients showed reduced cardiac diastolic function; 2. Severe patients exhibited exacerbated right ventricular systolic function; 3. All patients showed impaired left ventricular strain, worse strain in severe patient. 4. The apical longitudinal strain of mild patients was higher than basal and middle segment. 5. There was a negative correlation between LV GLS and log TnT-hs, as well as NT-pro BNP. 6. The EF value and strain of left atrium of mild and severe patients decreased; 7. LV GLS, LV GCS and LA GLS area under the ROC curve to predict the disease severity were 0.698, 0.758 and 0.782 respectively. 8. In the follow-up of severe patients, left atrial and ventricular strain showed an increased trend.Conclusions: These findings suggested that left ventricular performance was subclinically impaired during COVID-9 infection irrespective of infection severity and the strain of LV and LA may predict the disease severity. The cardiac function had an increasing trend for severe patients.

Background: The initial mechanism of COVID-19 is the binding of the virus to ACE2. Since the heart and the vessels also express ACE2, they both could become targets of the virus. However, cardiac performance of patients in ICU and general ward may be different, requested individualized treatment. The aim of this study is to explore the global and segmental myocardial performance of the severe and mild COVID-19 patients.Methods: 45 patients, including 25 mild and 20 severe patients in intensive care unit (ICU) with COVID-19 infection were included in this study. The clinical history, laboratory test and standard and strain echocardiography were performed at admission. Of them, 13 severe patients received serial echocardiography, especially, 10 patients received echocardiographic examinations more than 7 times. Results: 1. Both mild and severe COVID-19 infected patients showed reduced cardiac diastolic function; 2. Severe patients in ICU exhibited exacerbated right ventricular systolic function; 3. Both mild and severe patients with COVID-19 showed impaired left ventricular strain, worse strain in severe patient. 4. The apical longitudinal strain of mild patients was higher than basal and middle segment. No difference among apical, middle and basal segments in severe patients. 5. There was a negative correlation between LV GLS and log TnT-hs, as well as NT-pro BNP. 6. The EF value and strain of left atrium of mild and severe patients decreased; 7. LV GLS, LV GCS and LA GLS area under the ROC curve to predict the disease severity were 0.698, 0.758 and 0.782 respectively. 8. In the follow-up of severe patients, left atrial and ventricular strain showed an increased trend.Conclusions: These findings suggested that left ventricular performance was subclinically impaired during COVID-9 infection irrespective of infection severity and the strain of LV and LA may predict the disease severity. The cardiac function had an increasing trend for severe patients treated in ICU.

Background The degree of myocardial injury, as reflected by troponin elevation, and associated outcomes among US hospitalized patients with Coronavirus Disease 2019 (COVID-19) are unknown. Objectives To describe the degree of myocardial injury and associated outcomes in a large hospitalized cohort with laboratory-confirmed COVID-19. Methods Patients with COVID-19 admitted to one of five Mount Sinai Health System hospitals in New York City between February 27th and April 12th, 2020 with troponin-I (normal value 0.09 ng/dL, n=530, 19.4%) were significantly associated with higher risk (adjusted HR 3.03, 95% CI 2.42-3.80; P, Condensed Abstract Myocardial injury reflected as elevated troponin in Coronavirus Disease (COVID-19) is not well characterized among US patients. We describe the prevalence of myocardial injury and its impact on outcomes among hospitalized patients with confirmed COVID-19 who had troponin-I measurements within 24 hours of admission (N=2,736). Elevated troponin concentrations (normal

Aims Limited information exists describing the results of transcatheter aortic valve replacement (TAVR) in patients with symptomatic severe non-calcific aortic stenosis (AS). We aimed to compare procedural, echocardiographic, and clinical outcomes among patients with non-calcific AS with those of senile calcific AS undergoing TAVR. Methods and results We retrospectively identified patients with non-calcific AS who received TAVR with self-expanding transcatheter heart valves in our centre. Clinical and echocardiographic outcomes, and post-procedural multi-detector computed tomography (MDCT) measures were compared to those in patients undergoing TAVR for calcific AS. Among 136 patients, 21 patients (15.4%) with native leaflet thickening and minimal calcification were identified (non-calcific group). The patients were significantly younger in the non-calcific group (70.0 [64.0-75.5] vs. 75.0 [69.0-78.0] years) with comparable STS-PROM scores (6.7 [4.8-8.9] vs. 8.2 [4.8-10.9] %). Predilation was performed less frequently (42.9% vs. 93.9%) and post-dilation more often (71.4% vs. 42.6%) in the non-calcific group. Both 30-day and one-year mortality were similar between groups (0% vs. 7.8% and 0% vs. 17.6%). Rates of post-implantation paravalvular leak ≥mild at six months (17.6% vs. 25.7%) were comparable despite lower implantation depth among non-calcific AS patients (10.9±5.7 vs. 7.2±4.3 mm) on post-implantation MDCT. Conclusions TAVR with self-expanding transcatheter heart valves appears to be safe and effective in patients with non-calcific AS.

The first onset of cardiac event of long QT syndrome (LQTS) was at young age and caused by emotional or physical triggers. We presented a 64-year-old woman who experienced recurrent ventricular arrhythmia after hemodialysis initiation because of end-stage renal disease. Persistent prolonged QTc interval and diagnosis of inherited LQT2 were missed at her first 3 years of hemodialysis. The patient was beta-blocker nonresponder for ventricular arrhythmias suppression and experienced multiple ICD discharge. We reported an inherited LQT2 case with uncommon clinical manifestations and the successful experience of mexiletine use in such a patient.

The hydraulic turbine model is the key factor which affects the analysis precision of the hydraulic turbine governing system. This paper discusses the basic principle of the hydraulic turbine matrix model and gives two methods to realize. Using the characteristic matrix to describe unit flow and torque and their relationship with the opening and unit speed, it can accurately represent the nonlinear characteristics of the turbine, effectively improve the convergence of simulation process, and meet the needs of high precision real-time simulation of power system. Through the simulation of a number of power stations, it indicates that, by analyzing the dynamic process of the hydraulic turbine regulating with 5-order matrix model, the calculation results and field test data will have good consistency, and it can better meet the needs of power system dynamic simulation.

Iatrogenic left main coronary artery dissection is a rare entity for cardiac surgery but could cause severe low cardiac output and a catastrophic outcome. There is no conclusive strategy about how to manage such a condition. Here, we report a middle-aged woman who manifested with severe low cardiac output after aortic and mitral valve replacement surgery. She was subsequently diagnosed with extensive left main coronary artery dissection involving the left anterior descending artery and left circumflex artery, which resulted in large extension of myocardial infarction. The complex and dangerous vascular lesion was successfully treated by bailout stenting.