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Background: Association among local hemodynamic parameters and their implications in development of acute coronary syndrome (ACS) have not been fully investigated. Methods: A total of 216 lesions in ACS patients undergoing coronary CT angiography (CCTA) before 1–24 months from ACS event were analyzed. High-risk plaque on CCTA was defined as a plaque with ≥2 of low-attenuation plaque, positive remodeling, spotty calcification, and napkin-ring sign. With the use of computational fluid dynamics analysis, fractional flow reserve (FFR) derived from CCTA (FFR CT ) and local hemodynamic parameters including wall shear stress (WSS), axial plaque stress (APS), pressure gradient (PG) across the lesion, and delta FFR CT across the lesion (ΔFFR CT ) were obtained. The association among local hemodynamics and their discrimination ability for culprit lesions from non-culprit lesions were compared. Results: A total of 66 culprit lesions for later ACS and 150 non-culprit lesions were identified. WSS, APS, PG, and ΔFFR CT were strongly correlated with each other (all p < 0.001). This association was persistent in all lesion subtypes according to a vessel, lesion location, anatomical severity, high-risk plaque, or FFR CT ≤ 0.80. In discrimination of culprit lesions causing ACS from non-culprit lesions, WSS, PG, APS, and ΔFFR CT were independent predictors after adjustment for lesion characteristics, high-risk plaque, and FFR CT ≤ 0.80; and all local hemodynamic parameters significantly improved the predictive value for culprit lesions of high-risk plaque and FFR CT ≤ 0.80 (all p < 0.05). The risk prediction model for culprit lesions with FFR CT ≤ 0.80, high-risk plaque, and ΔFFR CT had a similar or superior discrimination ability to that with FFR CT ≤ 0.80, high-risk plaque, and WSS, APS, or PG; and the addition of WSS, APS, or PG into ΔFFR CT did not improve the model performance. Conclusions: Local hemodynamic indices were significantly intercorrelated, and all indices similarly provided additive and independent predictive values for ACS risk over high-risk plaque and impaired FFR CT .

Transjugular intrahepatic portosystemic shunt (TIPS) is an established treatment for complications of portal hypertension; yet the influence of anesthesia modality on procedural performance and hemodynamics remains insufficiently characterized. This retrospective single-center study compared radiation exposure, procedural parameters, and portal hemodynamics between procedures performed with and without general anesthesia (GA). A total of 84 patients were identified, of whom 62 were age- and sex-matched into two equal groups: group 1 (GA, n = 31) and group 2 (no GA, n = 31). Evaluated parameters included length of hospital stay, dose area product (DAP), fluoroscopy time (FT), contrast volume, number of digital subtraction angiography series, procedure duration, and pre- and post-TIPS measurements of portal venous pressure, central venous pressure (CVP), and portosystemic pressure gradient (PPG). Non-parametric statistical tests were applied. Patients in group 1 had significantly shorter postoperative hospital stay (median 6 days; interquartile range (IQR): 4–7) than those in group 2 (8 days; IQR 6–8; p = 0.006). Radiation dose was significantly lower in group 1, with a median DAP of 127.1 Gy*cm 2 (IQR 64.6–201.8) compared to 325 Gy*cm 2 (IQR 162.3–393.7; p = 0.02) in group 2. FT was also reduced under GA (12.2 minutes; IQR 9.6–15.9 vs. 16.0 minutes; IQR 11.5–25.9; p = 0.01), as was contrast volume (75 ml; IQR 60–100 vs. 90 mL; IQR 60–110; p = 0.01). PPG reduction was achieved in both groups, despite higher CVP under GA. These findings suggest that GA may facilitate more stable procedural conditions during TIPS, reducing radiation dose and contrast use without compromising hemodynamic effectiveness.

Background Physics-based cardiovascular models are only recently being considered for disease diagnosis or prognosis in clinical settings. These models depend on parameters representing the physical and physiological properties of the modeled system. Personalizing these parameters may give insight into the specific state of the individual and etiology of disease. We applied a relatively fast model optimization scheme based on common local optimization methods to two model formulations of the left ventricle and systemic circulation. One closed-loop model and one open-loop model were applied. Intermittently collected hemodynamic data from an exercise motivation study were used to personalize these models for data from 25 participants. The hemodynamic data were collected for each participant at the start, middle and end of the trial. We constructed two data sets for the participants, both consisting of systolic and diastolic brachial pressure, stroke volume, and left-ventricular outflow tract velocity traces paired with either the finger arterial pressure waveform or the carotid pressure waveform. Results We examined the feasibility of separating parameter estimates for the individual from population estimates by assessing the variability of estimates using the interquartile range. We found that the estimated parameter values were similar for the two model formulations, but that the systemic arterial compliance was significantly different ( p < 10 - 6 ) depending on choice of pressure waveform. The estimates of systemic arterial compliance were on average higher when using the finger artery pressure waveform as compared to the carotid waveform. Conclusions We found that for the majority of participants, the variability of parameter estimates for a given participant on any measurement day was lower than the variability both across all measurement days combined for one participant, and for the population. This indicates that it is possible to identify individuals from the population, and that we can distinguish different measurement days for the individual participant by parameter values using the presented optimization method.

(1) Background: The purpose of this prospective study was to determine the changes in primary hemodynamic parameters and oxygen saturation in systemically healthy patients during the surgical procedure involving crown lengthening. (2) Methods: A total of 44 patients who required a crown-lengthening procedure in a single tooth in the maxillary arch were included in this study. Heart rate (HR), blood pressure (BP) and oxygen saturation (SpO2) were measured in all the subjects at three different intervals: before injecting the anesthetic (T1), after the anesthetic injection (T2) and after the procedure (T3). Descriptive statistics were computed, and observations were recorded as mean and standard deviation (SD). Analysis of variance (ANOVA) was used to compare the mean observation within parameters at different time intervals. (3) Results: All primary hemodynamic parameters were increased in the T2 phase over T1 and decreased in the T3 phase over T2. However, SpO2 decreased in both the T2 and T3 phases compared to the initial T1 phase. No significant differences were observed among the primary hemodynamic variables. However, SpO2 showed a significant difference (p = 0.013) among the T1, T2 and T3 phases. (4) Conclusions: Further study with larger sample size is required in order to analyze the accurate hemodynamic alterations.

The common iliac artery supplies blood to the lower extremities, and stenosis in this region severely impacts hemodynamics. This study investigates the effects of 25%, 50%, and 75% iliac artery stenosis on key hemodynamic parameters using a fluid–structure interaction (FSI) approach. Semi-idealized geometries reconstructed from patient-specific data modeled realistic arterial behavior. Parameters such as wall displacement, time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), high oscillatory low shear magnitude (HOLMES) index, and endothelial cell activation potential (ECAP) were evaluated. Results showed peak wall displacement of 2.85 mm in the bifurcation zone under 75% stenosis. TAWSS increased with stenosis severity, peaking in stenotic regions and decreasing significantly downstream. OSI was highest in non-stenosed right branches and bifurcation areas, indicating multidirectional shear forces. HOLMES values were lowest downstream of stenoses, indicating disturbed flow. ECAP exceeded the thrombosis risk threshold (1.4 Pa−1) in post-stenotic zones under 75% stenosis, suggesting a higher risk of clot formation. These results demonstrate that stenosis disrupts local flow and causes hemodynamic changes downstream, emphasizing the need for comprehensive clinical assessment beyond the stenotic site. Regions with elevated ECAP and low HOLMES downstream may be prone to thrombosis, highlighting the importance of careful hemodynamic monitoring for treatment strategies.

Background Lidocaine and magnesium sulfate have become increasingly utilized in general anesthesia. The present study evaluated the effects of these drugs, isolated or combined, on hemodynamic parameters as well as on the cisatracurium-induced neuromuscular blockade (NMB). Methods At a university hospital, 64 patients, ASA physical status I and II, undergoing elective surgery with similar pain stimuli were randomly assigned to four groups. Patients received a bolus of lidocaine and magnesium sulfate before the tracheal intubation and a continuous infusion during the operation as follows: 3 mg.kg − 1 and 3 mg.kg − 1 .h − 1 (lidocaine - L group), 40 mg.kg − 1 and 20 mg.kg − 1 .h − 1 (magnesium - M group), equal doses of both drugs (magnesium plus lidocaine - ML group), and an equivalent volume of isotonic solution (control - C group). Hemodynamic parameters and neuromuscular blockade features were continuously monitored until spontaneous recovery of the train of four (TOF) ratio (TOFR > 0.9). Results The magnesium sulfate significantly prolonged all NMB recovery features, without changing the speed of onset of cisatracurium. The addition of lidocaine to Magnesium Sulfate did not influence the cisatracurium neuromuscular blockade. A similar finding was observed when this drug was used alone, with a significantly smaller fluctuation of mean arterial pressure (MAP) and heart rate (HR) measures during anesthesia induction and maintenance. Interestingly, the percentage of patients who achieved a TOFR of 90% without reaching T1–95% was higher in the M and ML groups. Than in the C and L groups. There were no adverse events reported in this study. Conclusion Intravenous lidocaine plays a significant role in the hemodynamic stability of patients under general anesthesia without exerting any additional impact on the NMB, even combined with magnesium sulfate. Aside from prolonging all NMB recovery characteristics without altering the onset speed, magnesium sulfate enhances the TOF recovery rate without T1 recovery. Our findings may aid clinical decisions involving the use of these drugs by encouraging their association in multimodal anesthesia or other therapeutic purposes. Trial registration NCT02483611 (registration date: 06-29-2015).

Fontan circulation is a fragile system in which imperfections at any of multiple levels may compromise the quality of life, produce secondary pathophysiology, and shorten life span. Increased inferior vena caval pressure itself may play a role in “Fontan failure”. This study describes a mock flow loop model (MFL) designed to quantitatively estimate pulmonary flow entrainment induced by continuous and pulsed flow injections. A patient generic 3D-printed phantom model of the total cavopulmonary connection (TCPC) with average dimensions matching those of a 2–4-year-old patient was inserted in an MFL derived from a reduced lumped parameter model (LPM) representing cardiovascular circulation. The LPM comprises four 2-element Windkessel compartments (compliance and resistance), approximating the upper and lower systemic circulations and the right and left pulmonary circulations. The prescribed cardiac output is about 2.3 L/min for a body surface area of 0.675 m2. The injections originate from an external pump through a 7–9 fr catheter, following a strict protocol suggested by the clinical team, featuring a variation in injection rate (flow rate), injection volume, and injection modality (continuous or pulsed). The key measurements in this study are the flow rates sampled at the distal pulmonary arteries, as well as at the upper and lower body boundaries. These measurements were then used to calculate effective entrainment as the difference between the measured and expected flow rates, as well as jet relaxation (rise and fall time of injection). The results show that for continuous or pulsed injections, varying the total volume injected has no significant influence on the entrainment rate across all injection rates. On the other hand, for both injection modalities, increasing the injection rate results in a reduction in entrainment that is consistent across all injected volumes. This study demonstrates the effectiveness of a high-speed injection jet entraining a slow co-flow while determining the potential for fluid buildup, which could ultimately cause an increase in caval pressure. To avoid the increase in caval pressure due to mass accumulation, we added a fenestration to our proposed injection jet shunt-assisted Fontan models. It was found that for a set of well-defined parameters, the jet not only can be beneficial to the local flow, but any adverse effect can be obviated by careful tuning. These results were also cross-validated with similar in silico findings.

Background TEA (thoracic epidural analgesia) is considered a basic method of analgesia used in thoracic surgeries. PVB (paravertebral block) is an alternative method. The thesis compares effectiveness of both methods in postoperative analgesia with particular focus on assessment of the postoperative pain management quality. Methods The study involved 2 groups of patients, each consisting of 30 patients undergoing posterolateral thoracotomy. The study group involved patients anesthetized applying PVB method, while the control group involved patients anesthetized with TEA. Hemodynamic and respiratory parameters as well as severity of pain assessed using NRS (numeric rating scale) during the first 3 days after the surgery, number of days of hospitalization, and the need to use additional pain relievers were taken into account in both groups. Evaluation of postoperative pain management quality was performed applying Clinical Quality Indicators in Postoperative Pain Management. Results No statistical significance was demonstrated between the groups in respect of hemodynamic and respiratory parameters values, the need to use additional pain relievers and the number of days of hospitalization. There was no statistically significant difference between the groups in respect of general assessment of pain management quality, except for the assessment of the lowest level of pain within the last 24 h of measurement. This result in TEA group was statistically significantly lower than the one in PVB group ( p  = 0.019). Conclusions In the assessment of postoperative pain management quality both analyzed methods are statistically significantly different only in the category of “lowest level of pain within the last 24 hours of measurement”, to the benefit of TEA group. No statistically significant difference has been observed between the two study groups with respect to the remaining parameters. Trial registration KB-0012/71/15. Date of registration 22 June 2015.

Background The effect of thoracic epidural analgesia (TEA) on splanchnic blood flow during abdominal surgery remains unclear. The purpose of this study was to examine whether the hemodynamic effects of TEA resulted in microcirculatory alterations to the intestinal serosa, which was visualized using incident dark-field (IDF) videomicroscopy. Methods An observational cohort study was performed. In 18 patients, the microcirculation of the intestinal serosa was visualized with IDF. Microcirculatory and hemodynamic measurements were performed prior to (T1) and after administering a bolus of levobupivacaine (T2). If correction of blood pressure was indicated, a third measurement was performed (T3). The following microcirculatory parameters were calculated: microvascular flow index, proportion of perfused vessels, perfused vessel density and total vessel density. Data are presented as median [IQR]. Results Mean arterial pressure decreased from 73 mmHg (68–83) at T1 to 63 mmHg (±11) at T2 ( p  = 0.001) with a systolic blood pressure of 114 mmHg (98–128) and 87 (81–97), respectively ( p  = 0.001). The microcirculatory parameters of the bowel serosa, however, were unaltered. In seven patients, blood pressure was corrected to baseline values from a MAP of 56 mmHg (55–57), while microcirculatory parameters remained constant. Conclusion We examined the effects of TEA on the intestinal serosal microcirculation during abdominal surgery using IDF imaging for the first time in patients. Regardless of a marked decrease in hemodynamics, microcirculatory parameters of the bowel serosa were not significantly affected. Trial registry number ClinicalTrials.gov identifier NCT02688946.

There is no data concerning the use of the intraseptal anaesthesia (ISA) for single tooth extraction. The aims of this study were to compare the clinical efficacy and haemodynamic responses of the ISA with the periodontal ligament anaesthesia (PLA) for single tooth extraction. Thirty-five randomly selected healthy patients (ASA I) undergoing maxillary lateral incisors extraction entered the study. Onset of anaesthesia, the width of the anaesthetic field and duration of anaesthesia were recorded by pinprick testing. Intensity of anaesthesia was evaluated on a visual analogue scale. Haemodynamic parameters were recorded simultaneously at different time points after anaesthesia injection. The two techniques of local anaesthesia did not show statistically significant differences regarding the success rate and onset of anaesthesia, while the duration of the ISA on the buccal site was significantly longer in comparison with the PLA. The intensity of the achieved anaesthesia, estimated by the experienced pain during procedure, pointed out that pain was recorded in 24% of cases in the ISA group, and in 19% in the PLA group without significant differences. Postoperative pain was found to be smaller in the ISA group (70.9% of treated sites) than in the PLA group (81.3% of treated sites); however, this difference was not significant. Although the heart rate increased in both groups, there were no significant differences in the patients' haemodynamic response between the ISA and the PLA. The results of the present study indicate that both techniques are useful and suitable for the routine tooth extraction.