Low Pressure Research Articles

Molecular dynamics simulation of solvation behavior and thickening properties of modified siloxanes in supercritical carbon dioxide under different pressure and temperature

Supercritical carbon dioxide (ScCO2) fracturing fluids have been limited in their application in unconventional reservoirs due to their weak proppant-carrying capacity resulting from their low viscosity. Consequently, numerous scholars have focused on modifying siloxanes to enhance their solubility and thickening performance in ScCO2. In this paper, the cohesive energy density, interaction energy, radial distribution function, shear viscosity and electrostatic potential distribution of modified siloxane with ScCO2 were calculated using molecular dynamics simulation. The effects of different temperatures and pressures on the dissolution and thickening ability of modified siloxanes in ScCO2 were investigated.The simulation results indicate that high temperature and low pressure have limited effects on promoting the solubility of modified siloxanes in ScCO2, with temperature exerting a more significant influence on solubility behavior than pressure. Additionally, PD4H+TMPTMA is less soluble in ScCO2 compared to PD4H+TAIC. The binding energy of ScCO2 and modified siloxanes decreases with increasing temperature but increases with increasing pressure. Van der Waals interactions and electrostatic interactions play decisive roles in the solubility of modified siloxanes in ScCO2. Finally, the thickening mechanism of modified siloxanes in ScCO2 was elucidated based on molecular structure and binding energy interactions.In summary, this paper aims to provide options and assistance in synthesis of better ScCO2 thickeners for unconventional reservoir fracturing applications through the study of modified siloxanes.

Study on the Spatio-temporal Evolutionary Properties of Gas-liquid Two-phase Flow in Centrifugal Pump as Turbine (PAT)

With the increasing complexity of the industrial production process, the transmission medium of the hydraulic turbine is no longer satisfied, and the gas-liquid two-phase mixed medium has to be considered. The presence of gas in the transmission medium will alters the internal flow structure of the hydraulic turbine and affect its operational stability. Therefore, for the purpose of clarifying the influence of inlet gas content on the internal flow of PAT, the unsteady flow of the PAT is simulated in this paper using numerical simulation. Based on the numerical simulation results, the influence of inlet gas content on the internal flow characteristics, characteristics of pressure fluctuation in impeller and volute, and vortex evolution of flow field are analyzed. The accumulation of gas phase leads to the emergence of vortices, and regions with low pressure values appear at the vortex generation. The major factor of the periodic variation of pressure fluctuation between volute and cut-water is the dynamic and static interference of impeller. The increase of gas content causes more flow disorder in the cut-water region and the volute contraction section. Since the gas in the flow channel is predominantly on the suction side of blades, the flow field on the suction side is more complex than that on the pressure side, and the amplitude of pressure fluctuation increases appropriately. The vortex structure is mainly distributed on balance hole, inlet area of impeller and suction side of blade. As the blade rotates, there are new shedding and growth of vortices, and finally attached to the volute wall. Increasing gas content enhances the influence of blade rotation on the vortex evolution characteristics in the volute and impeller.

A biopsychosocial approach to phenotyping people with knee osteoarthritis awaiting total knee arthroplasty: A secondary cohort analysis

BackgroundPrevious research showed chronic post-total knee arthroplasty (TKA) pain in 20% of people with knee osteoarthritis (KOA). Various preoperative biopsychosocial-related factors have been described, but phenotyping people with KOA awaiting TKA based on these factors is still lacking. This could be relevant to understanding differences in TKA surgery responses. ObjectiveTo identify phenotypes in people with KOA awaiting TKA and differences in post-TKA pain based on preoperative biopsychosocial factors. MethodsPeople with KOA awaiting TKA in 4 hospitals in Belgium and the Netherlands were included. A cross-sectional latent profile analysis was conducted on structural, metabolic, functional, pain-related, psychological and social variables. Concurrent validity was tested using 3-step multinomial logistic regression. The difference in one-year post-TKA pain was examined with linear mixed model analysis. ResultsTwo hundred and seventeen participants were included in the latent profile analysis with a mean (SD) age of 65.5 (7.7) years, including 109 women. A model with 2 phenotypes differed in 14 out of 21 variables. Participants with phenotype 2 (28%) had a higher body mass index (BMI), higher chance of having less structural damage (KOA grade), lower mean quadriceps strength and physical function (Knee Society Scoring System functional and 30-second chair stand test), higher pain intensity, number of pain locations, and indices of central sensitisation (temporal summation, central sensitisation inventory score, and lower pressure pain thresholds), higher pain catastrophising, anxiety and depression, and higher post-TKA pain intensity compared to phenotype 1 (72%). Concurrent validity was confirmed in 3 out of 4 variables. ConclusionsPhenotype 2 (28%) with nociplastic pain characteristics in combination with worse psychological factors, BMI, functional and structural factors, and phenotype 1 (72%) not representing these characteristics were identified. Phenotype 2 had worse pain intensity scores after TKA compared to phenotype 1. Attention to the characteristics of phenotype 2 is warranted concerning post-TKA pain. Database registrationThe protocol is registered at ClinicalTrials.gov (NCT05380648).

Influence of Menthol Infusion on Esophageal Peristalsis in Patients With Ineffective Esophageal Motility.

Activation of the cold receptor, transient receptor potential melastatin 8 (TRPM8) by menthol inhibits esophageal secondary peristalsis in healthy adults. Ineffective esophageal motility (IEM) is common. This study is to evaluate the effects of acute infusion of menthol on esophageal peristalsis in patients with IEM. Twenty patients with IEM (males 11, mean age 36) were studied for esophageal peristalsis using high-resolution manometry. All participant had primary peristalsis performed with 10 water swallows and secondary peristalsis generated with 10 rapid air injections of 20 mL via mid-esophageal infusion port. Two different sessions by randomly performing acute administration of placebo or menthol (3 mM) were used for testing their effects on esophageal peristalsis. Menthol infusion had no effects on distal contractile integral (P = 0.471), distal latency (P = 0.58), or complete peristalsis (P = 0.251). Menthol infusion did not change basal lower esophageal sphincter pressure (P = 0.321), esophagogastric junction contractile integral (P = 0.758), or integrated relaxation pressure (P = 0.375) of primary peristalsis, but reduced upper esophageal sphincter pressure (P = 0.037). Infusion of menthol significantly reduced the frequency of secondary peristalsis for air injects of 20 mL (P = 0.002), but did not affect distal contractile integral of secondary peristalsis for air injections of 20 mL. This work has suggested that activation of TRPM8 by menthol can attenuate mechanosensitivity of secondary peristalsis in response to rapid air distension regardless of the presence of IEM.

Influence of blood pressure targets on inflammation and associations between inflammatory markers and vasopressor usage after cardiac arrest - a substudy of a randomized clinical trial

Abstract Background Following resuscitation from cardiac arrest, a profound systemic inflammatory response may develop. In observational studies of critically ill patients an association between levels of inflammation and vasopressor usage has been found. Higher levels of inflammation may lead to higher vasopressor needs due to vasoplegia and cardiac dysfunction, however, catecholamines, including vasopressors also have immune modulatory effects. In the Blood Pressure and Oxygenation Targets in Post resuscitation Care (BOX) trial patients were randomized to a high or low blood pressure target, and vasopressor usage was increased in the high blood pressure target group. Therefore, the inflammatory response evoked by cardiac arrest, may have been altered by differences in vasopressor usage according to blood pressure target in this trial. Purpose To determine if differences in vasopressor and inotropy usage associated with randomization to a high compared to a low blood pressure target affects the inflammatory response after OHCA, and to investigate the association between inflammation and vasopressor and inotropy usage. Methods In the BOX trial, comatose OHCA patients with a presumed cardiac etiology were randomized to a blinded intervention of either a high (77mmHg) or a low blood pressure target (63mmHg). The inflammatory markers of leukocytes and CRP were measured at 0, 24, 48, and 72 hours. The average Vasoactive-Inotropic Score (VIS) was determined during initial 72 hours. The associations between average CRP, leukocytes, and VIS during initial 72 hours were determined by Spearman’s correlation analysis. Results The BOX trial included 789 resuscitated comatose OHCA patients, and 788 patients had at least 1 measurement of leukocytes and CRP. The median age was 64 (IQR 54-73), females constituted 19%, 1 year mortality was 36%. There was no difference in leukocytes and CRP at admission between the high and low blood pressure target groups (Figure 1). Leukocytes were slightly higher at 24 hours (p<0.01) in the high blood pressure target group, but no group differences were found at 48 and 72 hours, and CRP levels did not differ at 24, 48, or 72 hours. The average VIS was 19 (11-32) and 11 (5-19), p<0.01, in the two groups, with VIS being consistently higher at all timepoints beyond ICU admission (all p<0.01, data not shown) in patients with a high blood pressure target. Both average CRP and leukocytes were weakly correlated with average VIS at 0-72 hours for both blood pressure targets, r=0.17 and r=0.20, respectively for a high target (both p<0.01), and r=0.17 and r=0.20, respectively for a low target (both p<0.01). Conclusions In conclusion, increased vasopressor and inotropy usage in this randomized, blinded study of blood pressure targets after OHCA, did not lead to clinically relevant changes in inflammation. Inflammatory markers and VIS were correlated to a similar degree for both blood pressure targets.Figure 1, LeukocytesFigure 2, CRP

Enhancing hydraulic efficiency in jet impingement sprinklers: Comparative analysis of aperture ratios compared with non-impingement sprinklers

A jet impingement sprinkler was designed based on asymmetric collision between the primary and secondary jets to replace traditional rotating sprinklers that require additional water distribution devices to provide suitable water distribution at low pressures. The study focuses on the ratio of apertures between primary and secondary nozzles, deriving a theoretical relationship based on jet momentum. The factors contributing to the variation in hydraulic performance between jet-impingement and non-impinging sprinklers are elucidated by combining hydraulic performance experiments with experiments using high-speed photography (HSP). The results show that the developed jet impingement sprinkler achieved a smoother water distribution trend. The wetted radius and Christiansen's uniformity coefficient of the jet impingement sprinkler were evaluated using the Criteria Importance via the Intercriteria Correlation (CRITIC) method. A comparison of the average scores shows that an aperture ratio of 1.66 performs best under full pressure. By contrast, an aperture ratio of 1.33 exhibited superior performance at low pressure. Jet deflection angle and jet breakup length were obtained through HSP experiments. The relative error between the measured and theoretical jet deflection angles was less than 5%, demonstrating the reliability of the proposed theoretical calculation method. A non-linear curve was used to establish the relationship among the aperture ratio, diameter of the primary nozzle exit, jet breakup length, average measured jet deflection angle, working pressure, and wetted radius. The relative error between the calculated and measured values was within 4%, indicating the suitability of the new formula for calculating the wetted radius of jet impingement sprinklers.

Incorporation of Multiple Binding Sites into an Adaptive MOF for Sieving Butane Isomers

AbstractEfficient separation of liner alkanes from branched alkanes is of prime importance in the petrochemical industry. Herein an adaptive metal‐organic framework FJI‐H38 is reported with 1D channel which can vary delicately ≈4.0 Å. The activated FJI‐H38 displays extremely large butane (n‐C4H10) capacity, especially at low pressure (44.15 cm3 g−1 at 298 K and 0.1 bar), but barely adsorbs isobutane (iso‐C4H10). Remarkably, FJI‐H38 possesses a high n‐C4H10/iso‐C4H10 selectivity of 246.75. Gas‐loaded single crystal X‐ray analysis and modeling calculation reveal that the synergetic effect of pore confinement and surfaces decorated with uncoordinated carboxyl group plays a critical role in the capture of the relatively smaller n‐C4H10 while the exclusion of the larger iso‐C4H10. In addition, dynamic breakthrough tests explicitly prove FJI‐H38 displays prominent separation performance for n/iso‐C4H10 under various conditions with ultra‐high productivity of high‐purity n‐C4H10 (42.48 L/kg, ≥99.0%) and iso‐C4H10 (42.35 L/kg, ≥99.95%).

Wave–Tide–Surge Interaction Modulates Storm Waves in the Bohai Sea

Typhoons, extratropical cyclones, and cold fronts cause strong winds leading to storm surges and waves in the Bohai Sea. A wave–flow coupled numerical model is established for storm events observed in 2022 caused by three weather systems, to investigate how storm waves are modulated by wave–tide–surge interaction (WTSI). Wave response is basically controlled by water level change in coastal areas, where bottom friction or breaking dominates the energy dissipation, and determined by the current field in deep water by altering whitecapping. Wave height increases/decreases are induced by positive/negative water level or obtuse/acute wave–current interaction angle, leading to six types of field patterns for significant wave height (Hs) responses. For the three storm events, Hs basically changed within ±5% in central deep water, while the maximum increase/decrease reached 160%/−60% in the coastal area of Laizhou Bay/Liaodong Bay. Based on maximum Hs and its occurrence time, WTSI modulation is manifested as the superposition effect of wave–tide and wave–surge interactions in both space and time scales, and occurrence time depends more on tide than surge for all three storms. The enhancement/abatement of WTSI modulation happens for consistent/opposite changing trends of wave–tide and wave–surge interaction, with the ultimate result showing the side with a higher effect.

Efficacy of online japanese intensive cardiac rehabilitation for secondary prevention for coronary artery disease: a comprehensive program including exercise, nutrition, mindfulness, and group support

Abstract Background/Introduction While comprehensive programs for cardiac rehabilitation are recommended for patients with coronary artery disease (CAD), systematic programs including nutrition, stress-management, and behavior change have not been clearly established. Purpose To comprehensively change the lifestyle of patients with CAD as secondary prevention, we developed an online based educational program "intensive cardiac rehabilitation for Japanese patients with CAD (J-ICR)" modifying ICR, a regimen covered by health insurance in the United States, to the program that has affinity with Japanese. Methods Online J-ICR program is set up as sessions for maintenance-phase CAD patients using an online application. J-ICR has 12 sessions held weekly for 3 hours per session, total 36 hours, aimed to integrate 4 components: 1) exercise guidance based on exercise prescription which contain aerobic exercise, resistance training, and multi-component exercise through online platforms, 2) dietary education focusing on "the Japan Diet", 3) stress management utilizing mindfulness, and 4) group support to enhance patient and medical-staff interaction. Twenty-two participants were randomly separated to Early Phase group and Late phase group. For verification of the efficacy of this program, we survey the adherence to the program and compared the changes in risk factor of CAD at 3 months defining Early phase group as intervention group and Late phase group as control. (Fig.1). Results After excluding 3 participants who withdrawn to participate, the remaining 19 participants were conducted the evaluation and 10 participants were in intervention group and 9 participants in control group, respectively. As for patient characteristics, the mean age was 66 years old, and all participants were male. History of CVD was comprising 8 cases of myocardial infarction and 15 cases of angina pectoris. As for the risk factors of CVD, there were not significant differences in mean low density lipoprotein (LDL) cholesterol (Intervention group 71.5mg/dl vs Control group 83.4mg/dl; p=0.12) or systolic blood pressure (SBP) (126mmHg vs 130mmHg; p=0.40) at base line between two groups. The average participating rate in program was 93.8% and there was no dropped out participant during the program in investigation group. After 3months, LDL cholesterol was not significantly decreased in both groups (mean reduction of Intervention group -0.3mg/dl, p=0.93 and control group -3.8mg/dl, p=0.43, respectively). However, there was significant reduction of SBP in intervention group (mean reduction 5.6mmHg, p=0.02) but in control group (mean reduction 2.4mmHg, p=0.42). (Fig.2). Conclusions This randomized controlled study showed the good adherence of J-ICR program and it suggested that J-ICR program has the effect on lowering systolic blood pressure at 3 months. Longer follow up data and the results of more participants are warranted to clarify the efficacy in real world prevention of CVD.

Case Report: Acute Abdomen Due to Ruptured Ovarian Ectopic Pregnancy at 8 Weeks

Background Ovarian pregnancy is a rare type of ectopic pregnancy, accounting for 0.5% to 1% of all ectopic pregnancies, with an incidence ranging from 1 in 2,100 to 1 in 60,000 pregnancies. Due to its rarity and the lack of common risk factors, diagnosing ovarian pregnancy is often challenging and typically occurs during surgical exploration. Case Presentation We present the case of a 40-year-old woman who experienced severe pelvic pain, light vaginal bleeding, and 8 weeks of amenorrhea. Upon arrival at the hospital, she was hemodynamically unstable, with low blood pressure and a rapid heart rate. An ultrasound revealed an empty uterus, an irregular mass on her right ovary, and free fluid in the pelvis. Her beta-hCG level was elevated, and her hemoglobin level was low. Given the suspicion of an ectopic pregnancy, she underwent emergency surgery. During the operation, the surgical team discovered a large amount of clotted blood and a ruptured mass on her left ovary measuring 10 x 9.5 cm. Due to heavy bleeding, they performed a left oophorectomy and salpingectomy. Histopathological analysis later confirmed the diagnosis of ovarian pregnancy. Conclusion This case underscores the challenges in diagnosing ovarian pregnancy and highlights the necessity for prompt surgical intervention, particularly in unstable patients. Early detection and appropriate management are critical to prevent life-threatening complications.

Cardiopulmonary exercise testing in long-term calcium channel blockers responders, does it normalize in the same way as pulmonary vascular resistance?

Abstract Background and aims Long-term calcium channel blockers (CCB) responders represent <10% of pulmonary arterial hypertension (PAH) patients and are known to have an excellent prognosis on high dose CCB. The few reports of lung histology of these patients suggest a predominant muscular thickening of the precapillary arterioles. Nevertheless, the classic intimal proliferation characteristic of PAH has also been reported, although to a lesser extent. Hence, we hypothesized that long-term CCB responders are likely to exhibit some degree of ventilatory inefficiency as a result of their impaired alveolo-capillary membrane. In this study, we aimed to evaluate the exercise performance of a contemporary cohort of long-term responders to CCB in terms of both exercise capacity and ventilatory efficiency, and whether there are differences depending on the haemodynamic severity. Methods We evaluated all long-term CCB responders with regular follow-up at our institution between 1996 to 2024 with at least one cardiopulmonary exercise test (CPET) and a right heart catheterization (RHC) within a three-year period, provided they had remained clinically stable without changes in pulmonary vasodilator treatment. Patients with additional PAH specific treatment were excluded. For data analysis purposes, the population was divided into 2 groups according to pulmonary vascular resistance (PVR). The cut-off point for PVR was set at ≥3. Results Twenty-four patients (91,6% female) with complete data were retrospectively enrolled. Baseline characteristics were as follows: median age 45.5 years (59-33) median mean pulmonary artery pressure of 26 mmHg (29-24) and median PVR of 3 WU (3-2.6). Regarding the whole cohort, peak oxygen consumption (pVO2) revealed mild impairment of functional capacity (mean pVO2: 1281 ± 245 ml/kg – 75 ± 15% of predicted). Ventilatory efficiency parameters were also mildy affected with low end-tidal carbon dioxide pressure at the anaerobic threshold (PETCO2@AT) (33.7±3.6mmHg), and increased minute ventilation (VE)/carbon dioxide output (VCO2) slope (33.5±4.5). The subgroup analysis depending on PVR showed no significant differences between groups in terms of pVO2 (1291.9 ±240 Vs. 1150 ±350 ml/kg, p:0.29 / 79%±16 vs 67%±12, p:0.8), VE/VCO2 slope (33 Vs. 34, p:0.21), or PETC02@AT (35 Vs. 33 mmHg, p:0.25). All CPET parameters by subgroups are displayed in Table 1. Conclusions Long-term CCB responders exhibit mildly reduced functional capacity. Moreover, they often fail to normalize the ventilatory efficiency parameters in most of the cases, even when PVR reaches close to normal values, suggesting persistent endothelial impairment.Results according to PVR

Arterial-myocardial coupling in primary AL amyloidosis. A validation study of vascular involvement

Abstract Background Primary AL amyloidosis is a rare yet lethal systemic disorder. Previously published own and others’ work indicated that vascular involvement in AL cardiac amyloidosis defined as low blood pressure or paradoxical vasodilation may independently affect survival. Mechanistic data will pave the way to validate the clinical role of vascular involvement in these patients. Purpose We sought to explore the presence of arterial-myocardial coupling in AL amyloidosis by investigating associations between markers of vascular and cardiac involvement. Methods We consecutively recruited n=152 newly diagnosed patients with AL amyloidosis that underwent thorough vascular examination including reactive vasodilation (flow mediated vasodilation, FMD and vasodilation in response to cold-pressor test) using high resolution ultrasonography. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (PWV) and aortic pressures and markers of arterial wave reflections were estimated using radial artery tonometry. In a subgroup of patients, transthoracic echocardiography (n=152) and cardiac magnetic resonance (CMR) (n=59) were performed. Results Vascular reactivity correlated with global longitudinal strain (GLS), left ventricle ejection fraction (LVEF)/GLS ratio and worse LV volumes. Vasodilation post-cold pressure test was correlated with LV mass. cSBP exhibited a negative correlation with markers of heart involvement, wall thickness markers, GLS, and CMR tissue characterization markers. A positive correlation between cSBP and LVEF, rotation and twist strain, myocardial work and contractility markers and late gadolinium enhancement (LGE). cDBP was associated with systolic function and contractility markers, with myocardial work indices and LGE. A negative relationship with GLS, LA strain, RV GLS and LA diameter and E/e’ was noted. In addition, T2 was negatively correlated with cDBP. SBP was correlated positively with LVEF, contractility markers, and LGE myocardium and negatively correlated with biomarkers of heart involvement, GLS, CMR structure and tissue characterization. DBP was positively correlated with LGE and myocardial work. A negative relation with NTproBNP, E/e’, RVSP, LA diameter and T2 mapping was noted. Time of wave reflections (Tr) was negatively correlated with rotation strain and positively correlated with circumferential strain, LA strain and LV structure. Ai@75 was positively correlated with myocardial work and contractility markers, and LGE. Ai@75 was negatively correlated with markers of heart involvement, LV structure, E/e’, worse GLS and adverse CMR tissue characterization. Conclusion Markers of peripheral vascular dysfunction were associated with cardiac structure and function acquired both with echocardiography and CMR in AL amyloidosis. This arterial-myocardial coupling supports the clinical role of peripheral vascular involvement in this disease and warrants further investigation.

The safety of in-hospital initiation of SGLT2 inhibitor with MRA therapy in patients hospitalized for heart failure with a reduced left ventricular ejection fraction and chronic kidney disease

Abstract Deferring in-hospital initiation of guideline-recommended medications in HFrEF has a few chances they will be initiated ambulatory, especially in the case of coexisting HFrEF and chronic kidney disease (CKD). The aim was to investigate the safety of in-hospital initiation of SGLT2i with MRA therapy for patients hospitalized for HFrEF and CKD 3. Methods 88 patients with HFrEF (on top of standard therapy ACE-I/ARB, B-blockers) and CKD (baseline eGFR between 30 and 60 ml/min) were included in the study. The potassium (K), creatinine (C), uric acid (UA) levels were estimated at baseline and week 12. After biochemical evaluation, patients started on spironolactone (SP) treatment with a median dose of 20 mg daily (titrated) and dapagliflozin (D) with a dose of 10 mg daily (D+SP). Blood pressure (BP), K, and renal function (RF) were checked at weeks 1 (in-hospital), 2, 4, 6, 8, 12 (ambulatory), and more frequently as necessary. Results After the start of therapy D+SP mean eGFR decreased significantly at week 1 from 51.14±9.18 to 46.26±7.91 ml/min/1.73m2 (P<.0001) and at week 2 to 44.18±6.51 ml/min/1.73m2 (-2.08±1.2; P<.001). At week 4 mean eGFR decreased to 42.73±6.86 ml/min/1.73m2 (-1.45±1.1; P<.05). So, a significant decrease in eGFR was observed only during the first month with no significant decrease at 6 and 12 weeks after the start of therapy. Six patients (8%) experienced a significant decline in RF resulting in temporary withdrawal of SP. At week 2 mean K level increased significantly from 4.56±0.63 to 5.07±0.57 mmol/L (P<.001). At weeks 4, 6, 8 K levels remain stable. At week 12 mean K level decreased significantly compared with week 2 (to 4.92±0.57 mmol/L, P<.05). The incidences of severe hyperkalemia (HK) (K+≥6.0mmol/L) were in three patients < 2 %, and moderate HK (K 5.5–5.9 mmol/L) occurred in ten patients (11 %). Patients who experienced inpatient hyperkalemia had a significantly lower eGFR than patients without episodes of HK (38.70 vs. 55.21 mL/min/1.73 m2; P<.0001). Episodes of HK were predicted by baseline K≥5.0 mmol/L and eGFR≤40 ml/min/1.73m2. Additionally, there was a significant improvement in blood UA (-1,53±0.49 mg/dL, P<.01). By multivariate analysis older age, diabetes, low diastolic BP (<60 mm Hg), eGFR≤40 ml/min/1.73m2 at baseline were associated with decreased RF (0.378, P<.01; 0.632, P<.001; 0.771, P<.0001; 0.397, P<.01; respectively), whereas episodes of HK were predicted by baseline K≥5.0 mmol/L and eGFR≤40 ml/min/1.73m2 (0.785, P<.0001; 0.542, P<.001; respectively). Conclusion Initiation of SGLT2i with MRA in patients hospitalized for HFrEF and CKD 3 was mainly safe although it caused an early drop in eGFR. Importantly, a fall in eGFR was observed during the first month. Concern about the reduction in eGFR should be in older diabetic patients with eGFR≤40 and low diastolic blood pressure. Although hyperkalemia was common, the occurrence of it was predicted by baseline potassium level and eGFR.

Clinical evidence of pacemaker implantation during gestation: a case series

Abstract Background Although recommended avoid any intervention during gestation in cases of poor tolerance to high degree atrioventricular block, pacemaker implantation may be necessary in pregnant women. Purpose To present outcomes of pacemaker implantation during gestation. Methods This prospective, single center study included 10 cases of pacemaker implantation during gestation (median age of patient - 26 years old at 18 weeks of gestation). We evaluated the further course of gestation and obstetric outcomes after implantation in comparison with pregnant with tachyarrythmias (n=111). Results Among 121 pregnant women with varying arrhythmias high degree atrioventricular block was detected in 10 cases (8,3%). In 6 cases this bradyarrhythmia diagnosed for the first time in gestation (60%). All pregnant with high degree atrioventricular block had clinical signs: dizziness and weakness (100%), syncope (70%), episodes of low blood pressure (100%). Pacemaker implantation performed due to hemodynamic instability and poor tolerance of bradyarrhythmia in all cases. Using electroanatomical mapping (Ensite Precision system)and echocardiographic guidance helped to reduce fluoroscopy time. For one pregnant implanted leadless pacemaker (Micra) with achieved more than 80% atrio-ventricular synchronization. Outcomes: further course of gestation characterized by increased incidence of uterine contractile activity (30%) in cases of high degree atrioventricular block, that was significantly higher than in pregnant with tachyarrhythmias (2%) (p=0.007). There were no differences in the rate of other complication: uterine blood flow violation (20% vs 12%, p=0.520), placental abraption (10% vs 5%, p=0.237) and preeclampsia (10% vs 5%, p=0.237). Vaginal type of delivery was in the majority of cases in both groups (70% vs 86%, p=0.553). Neonatal outcomes characterized with normal range of fetal birth weight (median 3163 vs 3212 grams, p=0.981) and 5 minute Apgar score (median 8.6 vs 8.7, p=0.564). There was no incidence of maternal and fetal mortality. In 12 month follow-up all patient have optimal electrical parameters of devise and remained stable over time. Conclusions High degree atrioventricular block in pregnant characterized by increased rate of uterine contractile activity. Pacemaker implantation during gestation can be effectively performed and associated with benign outcomes.

In vivo study of pulmonary artery remodeling and pulsatility in long Fontan patient

Abstract Background Pulmonary vasculopathy associated with Fontan circulation is a relatively unexplored entity that could have clinical and therapeutic implications. Purpose Our aim was to evaluate the physiology of the pulmonary artery in patients with Fontan circulation using conventional right heart catheterization (RHC) and intravascular ultrasound (IVUS). Methods From December 2022 to January 2024, data from all consecutive Fontan patients undergoing RHC were prospectively collected at a tertiary referral center for adult congenital heart disease. Pressures and pulmonary artery wall high-definition IVUS recordings (OptiCrossTM, 60 MHz, Boston Scientific) were recorded at rest and during apnea. Pathological Fontan pressure was defined when as exceeding 15 mmHg. IVUS pulsatility index was defined as [(systolic lumen area - diastolic lumen area)/(diastolic lumen area) ×100], Peterson's elastic modulus as (pulmonary pulse pressure/IVUS pulsatility index), and area of wall thickness as [(wall area - lumen area)/(lumen area) x100)]. In the literature, the mean ± standard deviation (SD) normal values of elastic modulus and wall thickness area have been reported as 21 ± 1.7 mmHg and 1.4 ± 1.3%, respectively, in healthy patients without pulmonary hypertension (1: doi: 10.1186/s12931-017-0568-z). We define an alteration in intrinsic pulmonary arterial wall viscoelastic properties as an elastic modulus > 70 mmHg, and we define structural pulmonary wall remodeling as an increase in wall thickness area greater than 5%. Results 13 patients were studied. Median age was 28.1 years interquartile range (IQR) (25.6- 41.4), 7 (53.9%) were female, and 4 (30,8%) were in functional New York Heart Associtation (NYHA) class I. RHC and pulmonary arterial wall IVUS values are presented in Figure 1. 6 (46.2%) had Fontan abnormal pressures at rest. All patients showed minimal pulse pressure in the pulmonary arteries synchronized with heart rate, median pulmonary pulse pressure (IQR) 3 (2-4) mmHg. This pulsatility was detected in the IVUS study in all patients, pulsatility index (median (IQR) 4.8 (3.3-10.1)) and elastic modulus (median (IQR) 51.5 (20.5-101.6) mmHg). All of them had some degree of structural pulmonary wall remodeling (>5% wall thickness area), and 10 (76.9%) of them had marked remodeling (> 10%). The median (IQR) of wall thickness area was 13.6 (10.5-18.3) % (Figure 2). We think that the pseudo-normality of the elastic modulus is due to a low pulmonary pulse pressure, however, structural remodeling could be secondary to the endothelial dysfunction present and described in arteries with very low pulsatility. Conclusions The IVUS evaluation of the pulmonary artery in Fontan patients may be useful for revealing significant information regarding pulmonary physiology. Pulmonary wall thickening has been observed, providing insight into altered structural remodeling of the pulmonary arteries in this population.

Clinical characteristics and outcomes of patients with takotsubo syndrome and dynamic left ventricular outflow tract obstruction

Abstract Background Left ventricular outflow tract obstruction (LVOTO) is recognized as a serious complication of Takotsubo syndrome (TTS). However, its impact on patient prognosis remains insufficiently investigated. Purpose This study aimed to assess clinical characteristics and short- and long-term outcomes of patients with TTS complicated by LVOTO. Methods Patients with TTS were enrolled from the Takotsubo Italian Network (TIN). The primary outcome was the composite of acute heart failure, cardiogenic shock, and mortality during hospitalization. Secondary outcomes included the single components of the primary outcome and the occurrence of death or TTS recurrence during follow-up. Results Overall, 881 patients were included in the study [median age 72.0 (63.0–78.0) years; 91.3% female], with LVOTO detected in 59 patients (6.7%). Low diastolic blood pressure, ST-segment elevation, and moderate-to-severe mitral regurgitation were independently associated with occurrence of LVOTO. Propensity score weighting regression analysis revealed a significant higher risk of the primary outcome (OR, 2.99; 95% CI, 2.22–4.02), acute heart failure (OR, 2.19; 95% CI, 1.59–3.02), cardiogenic shock (OR, 4.56; 95% CI, 3.07–6.78), and in-hospital mortality (OR, 2.42; 95% CI, 1.13–5.21) in patients with TTS complicated by LVOTO. No significant association between LVOTO and long-term mortality or TTS recurrence was observed during follow-up. Conclusions In this real-world evidence study, LVOTO was detected in about 7% of TTS patients and was associated with a significantly higher risk of adverse events during hospitalization, including mortality. Early detection of LVOTO can aid in prognostic assessment and guide therapeutic management in patients with TTS.

Incidence and predictors of radial artery occlusion following transradial coronary procedures

Abstract Background Transradial access for percutaneous coronary procedures has grown in popularity because of its advantages over the femoral approach. However, the benefit is overshadowed by an increased rate of radial artery occlusion (RAO). We aim to assess incidence and predictors of RAO after transradial catheterization. The anatomic variations of the radial artery (RA) were also studied. Methods This prospective study enrolled 427 patients who underwent coronary angiography or angioplasty via transradial access. An ultrasound evaluation of forearm arteries was performed. In case of RAO, another ultrasound check-up was performed after 1 month and 3 months of the procedure. Results Our study population includes 288 patients (32.6% female). The mean age was 61.9 ± 11.1 years. RAO occured in 48 patients (11.24%), among whom spontaneous recanalization was observed within 3 months in 15 patients (32.6%). On multivariate analysis, a younger age (OR 0.642 [CI 95%: 0.480 – 0.858], P = 0.031), low periprocedural systolic blood pressure, (OR 0.598 [CI 95%: 0.415 – 0.862], P = 0.007), a small radial diameter (OR 0.371 [CI 95%: 0.323 – 0.618], P = 0.031), insufficient anticoagulation (OR 0.287 [CI 95%: 0.163 – 0.505], P < 0.001), occlusive hemostasis (OR 0.128 [CI 95%: 0.047 – 0.353], P < 0.001), and a long duration of hemostasis emerged as independent predictors of radial occlusion. The overall incidence of radial artery anatomic variations was 14,8% (n=63). Among these patients, 40 (63.5%) had a high radial origin, 18 (28.6%) had extreme radial artery tortuosity, and 5 (7.9%) had a full radioulnar loop. Conclusion The incidence and prevalence of radial artery occlusion is expected to increase. Insufficient heparinization and occlusive hemostasis are the main modifiable predictors. The preventive strategy should focus primarily on these 2 predictive factors.

Effect of pre-procedural blood pressure on one-year cardiovascular events after percutaneous coronary intervention in patients with acute myocardial infarction

Abstract Background Although high systolic blood pressure (SBP) and low diastolic blood pressure (DBP) are associated with adverse cardiovascular outcomes in coronary artery disease, their impact on patients with acute myocardial infarction (AMI) remains unclear. Methods This multicenter prospective study included 874 AMI patients undergoing percutaneous coronary intervention (PCI) with pre-procedural blood pressure recorded. Patients with cardiogenic shock and missing blood pressure data were excluded. The patients were categorized based on SBP (high ≥120 mmHg, low <120 mmHg) and DBP (high ≥70, low <70 mmHg) into four groups: high SBP and high DBP (HSHD), high SBP and low DBP (HSLD), low SBP and high DBP (LSHD), and low SBP and low DBP (LSLD) group. The primary endpoint was a composite of all-cause mortality, myocardial infarction, stroke, and major bleeding. Results The average age of the patients was 68.9 years, with a mean pulse pressure of 58 ± 19 mmHg. The Kaplan-Meier curves showed significant differences in the primary endpoints among the four groups (Log-rank test, p <0.001). At 12 months, the primary endpoint occurrence was highest in the HSLD group (13.3%) and lowest in the LSHD group (2.4%). Additionally, multivariate Cox regression analysis revealed that the HSLD group, compared to the HSHD group, was independently correlated with an increased risk of cardiovascular events (hazard ratio 2.43, 95% confidence interval 1.16-5.11; p = 0.019). Conclusion Pre-procedural HSLD serves as an independent predictor and is associated with one-year adverse cardiovascular outcomes in AMI patients.Patient diagramKaplan-Meier one-year outcome

The effects of SGLT2 inhibitors on right ventricle functions in heart failure patients: update meta-analysis of the current literature

Abstract Background There is some discrepancy in the present studies concerning the effect of sodium-glucose cotransporter type 2 (SGLT2) inhibitors on right ventricular (RV) functions in heart failure (HF) patients. The current meta-analysis was focused on determining the impact of SGLT2 inhibitors on RV functions in such individuals. Methods Two independent investigators searched PubMed, Google Scholar, and the Cochrane Library for articles of interest. To analyze heterogeneity, Higgins' I2 as well as prediction intervals and Egger's test were utilized to assess heterogeneity. The Newcastle-Ottawa standard ratings approach was used to assess the quality of observational studies. The Robin-I risk of bias algorithm was used to assess the bias risks of randomized studies. Results This meta-analysis evaluated 8 studies in total. Over the follow-up time frame, patients who used SGLT-2 inhibitors had substantially lower systolic pulmonary artery pressure (sPAP) and higher TAPSE values (mean difference (MD) = 1.30 [0.78;1.82], p =0.002 and MD =-5.39 [-7.88; -2.89], p=0.003, respectively). There was no significant difference in RVS’ values between follow-up and baseline (MD=1.38 [-1.35;3.80], p=0.169). However, as compared to the baseline period, fractional area contraction (FAC) values were substantially larger at the end of the follow-up period (MD=5.40 [3.74;7.07], p=0.015). Conclusion To the best of our knowledge, this is the first meta-analysis assessing the impact of SGLT2 inhibitors on RV function in HF patients. Our findings suggest that SGLT2 inhibitors may improve RV performance in HF patients.

Tongue Pressure and Grip Strength as Indicators of Persistent Dysphagia After Acute Stroke.

This study aimed to identify the independent predictors of postacute stroke dysphagia at discharge using sarcopenia-related parameters. This single-center prospective observational study assessed consecutive inpatients diagnosed with cerebral infarction or cerebral hemorrhage upon admission to the stroke unit. Tongue pressure, grip strength, and body composition were evaluated within 48h. Dysphagia was defined by a functional oral intake scale of ≤ 5. Patient characteristics were compared between non-dysphagia and dysphagia groups using Mann-Whitney or chi-squared tests. Logistic regression analysis was performed using age, sex, tongue pressure, grip strength, skeletal muscle mass index (SMI), and National Institutes of Health Stroke Scale (NIHSS) scores as explanatory variables, with dysphagia at discharge as the objective variable. A total of 302 patients (mean age: 69.4 ± 13.8 years, 67.5% male) were analyzed, with 64 having dysphagia at discharge (21.2%). The dysphagia group was significantly older (p<0.001), had higher NIHSS scores on admission (p<0.001), lower SMI (p = 0.002), lower grip strength (p<0.001), and lower tongue pressure (p<0.001) than the non-dysphagia group. Logistic regression revealed that age (OR: 1.042, p = 0.018), tongue pressure (OR: 0.954, p = 0.010), and grip strength (OR: 0.943, p = 0.048) on admission were independent predictors of dysphagia at discharge, while NIHSS scores (OR: 1.403, p = 0.106), sex, and SMI (OR: 1.403, p = 0.150) were not. Older age, reduced tongue pressure, and reduced grip strength are strong predictors of persistent poststroke dysphagia at discharge. Thus, muscle strength is a more valuable parameter than muscle mass in predicting persistent poststroke dysphagia.