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Arterial stenosis is a high-risk disease accompanied by large amounts of calcified deposits and plaques that develop inside the vasculature. These deposits should be reduced to improve blood flow. However, current methods used to reduce stenosis require externally-controlled actuation systems resulting in limited workspace or patient risks. This results in an unexplored preference regarding the revascularization strategy for symptomatic artery stenosis. In this paper, we propose a novel internally-actuated solution: a magnetic spring-loaded rotablation catheter. The catheter is developed to achieve stenosis-debulking capabilities by actuating drill bits using two internal electromagnetic coils and a magnetic reciprocating spring-loaded shaft. The state-space model of the catheter is validated by comparing the simulation results of the magnetic fields of the internal coils with the experimental results of a fabricated prototype. Contact forces of the catheter tip are measured experimentally, resulting in a maximum axial force of 2.63 N and a torque of 5.69 mN-m. Finally, we present interventions in which the catheter is inserted to a vascular target site and demonstrate plaque-specific treatment using different detachable actuator bits. Calcified deposits are debulked and visualized via ultrasound imaging. The catheter can reduce a stenosis cross-sectional area by up to 35%, indicating the potential for the treatment of calcified lesions, which could prevent restenosis.

OBJECTIVE: The ocular vascular system plays an important role in preserving the visual function. Alterations in either anatomy or hemodynamics of the eye may have adverse effects on vision. Thus, an imaging approach that can monitor alterations of ocular blood flow of the deep eye vasculature ranging from capillary-level vessels to large supporting vessels would be advantageous for detection of early stage retinal and optic nerve diseases. METHODS: We propose a super-resolution ultrasound localization microscopy (ULM) technique that can assess both the microvessel and flow velocity of the deep eye with high resolution. Ultrafast plane wave imaging was acquired using an L22–14v linear array on a high frequency Verasonics Vantage system. A robust microbubble localization and tracking technique was applied to reconstruct ULM images. The experiment was first performed on pre-designed flow phantoms in vitro and then tested on a New Zealand white rabbit eye in vivo calibrated to various intraocular pressures (IOP) – 10 mmHg, 30 mmHg and 50 mmHg. RESULTS: We demonstrated that retinal/choroidal vessels, central retinal artery, posterior ciliary artery, and vortex vein were all visible at high resolution. In addition, reduction of vascular density and flow velocity were observed with elevated IOPs. CONCLUSION: These results indicate that super-resolution ULM is able to image the deep ocular tissue while maintaining high resolution that is comparable with optical coherence tomography angiography. SIGNIFICANCE: Capability to detect subtle changes of blood flow may be clinically important in detecting and monitoring eye diseases such as glaucoma.

A double-outlet left ventricle (DOLV) is a congenital cardiac anomaly that rarely is encountered. This case report demonstrates the echocardiographic features of DOLV in the form of the pulmonary artery arising completely from the left ventricle with D-looped ventricles, especially when evaluated by intraoperative transesophageal echocardiography (TEE), along with the correlation of characteristic features with cardiac computerized tomography. The features pertinent to the differentiation of DOLV from double-outlet right ventricle and congenitally corrected transposition of the great arteries by echocardiography have been described. To the authors' knowledge, this was the first report of intraoperative TEE in the case of DOLV. In addition, the use of intraoperative echocardiography to rule out coronary compression as a cause for post-repair ventricular tachycardia, by use of TEE to rule out ventricular dysfunction and regional wall motion abnormalities, as well as epicardial echocardiography to demonstrate normal coronary blood flow, has been reported.

A man in his 80s undergoing chronic hemodialysis presented with a high fever. A 10-cm soft mass was palpable in his right buttock. Abdominal computed tomography and angiography showed an incomplete-type unilateral persistent sciatic artery aneurysm (PSAA) with gas patterns and a blood flow through the aneurysm. Incision drainage was performed after arterial embolization. Gram staining of the hematoma showed gram-positive cocci that had formed chains, thus leading to a diagnosis of an infected PSAA. Drainage by incision after arterial embolization was used as the therapeutic method of choice for a massive infected PSAA with a sustained blood flow in order to prevent sciatic nerve injury and bleeding associated with PSAA resection.

Aim Coronary plaque rupture is the main cause of acute coronary syndrome (ACS), but the role of blood flow features around plaque rupture for ACS is still unknown. The present study aimed to assess the relationship between the geometric configuration of ruptured plaque and ACS occurrence using computational fluid dynamics (CFD) by moving particle method in patients with coronary artery disease. Methods In this study, 45 patients with coronary artery disease who underwent three-dimensional intravascular ultrasound (IVUS) and had a coronary ruptured plaque (24 plaques with provoked ACS, 21 without) were included. To compare the difference in blood flow profile around ruptured plaque between the patients with and without ACS, the IVUS images were analyzed via the novel CFD analysis. Results There were no significant differences in localized flow profile around ruptured plaque between the two groups when the initial particle velocity was 10.0 cm/s corresponded to a higher coronary flow velocity at ventricular diastole. However, when it was 1.0 cm/s corresponded to lower coronary flow velocity at ventricular systole, particles with lower velocity (0 ≤ V ≤ 5 cm/s) were more prevalent around ACS-PR (p=0.035), whereas particles with higher velocity (10 ≤ V ≤ 20 cm/s) were more often detected in silent plaque ruptures (p=0.018). Conclusions Three-dimensional IVUS revealed that coronary plaque rupture was a complex one with a wide variety of its stereoscopic configuration, leading to various patterns of the local coronary flow profile. A novel CFD analysis suggested that the local flow was more stagnant around ACS-provoked ruptures than in silent ones.

Background: We describe a simple and novel technique for cerebral protection during left subclavian artery (SA) stenting by inflation of a balloon-guiding catheter inside the aortic arch at the SA origin. Methods: A total of 12 patients with left SA stenosis underwent SA stenting with inflation of a balloon-guiding catheter inside the aortic arch at the left SA origin between January 2020 and December 2020. The SA stenting procedures under proximal protection were retrospectively reviewed to assess ischemic complications, hyperintense spots on diffusion-weighted imaging (DWI), and flow direction of left vertebral artery (VA) during balloon-guiding catheter inflation using ultrasonography (US). Results: The success rate of the SA stenting procedure was 100% with no symptomatic ischemic complications. None of the 12 patients showed small hyperintense spots in DWI. In all patients, the left VA on US during balloon inflation showed retrograde blood flow. Conclusions: The left VA on US had retrograde blood flow during inflation of the balloon-guiding catheter inside the aortic arch at the SA origin. Therefore, the proximal balloon protection inside the aortic arch at the SA origin is a simple and maybe a safe technique for cerebral protection during SA stenting.

Background Pseudo-spiral Cartesian sampling with compressed sensing reconstruction has facilitated highly accelerated 4D flow magnetic resonance imaging (MRI) in various cardiovascular structures. However, unlike echo planar imaging (EPI)-accelerated 4D flow MRI, it has not been validated in whole-heart applications. Hypothesis Pseudo-spiral 4D flow MRI (PROUD [PROspective Undersampling in multiple Dimensions]) is comparable to EPI in robustness of valvular flow measurements and remains comparable as the undersampling factor is increased and scan time reduced. Study Type Prospective. Population Twelve healthy subjects and eight patients with valvular regurgitation. Field Strength/Sequence 3.0 T; PROUD and EPI 4D flow sequences, 2D flow and balanced steady-state free precession sequences. Assessment Valvular blood flow was quantified using valve tracking. PROUD- and EPI-based measurements of aortic (AV) and pulmonary (PV) flow volumes and left and right ventricular stroke volumes were tested for agreement with 2D MRI-based measurements. PROUD reconstructions with undersampling factors (R) of 9, 14, 28, and 56 were tested for intervalve consistency (per valve, compared to the other valves) and preservation of peak velocities and E/A ratios. Statistical Tests We used repeated measures ANOVA, Bland-Altman, Wilcoxon signed rank, and intraclass correlation coefficients. P < 0.05 was considered statistically significant. Results PROUD and EPI intervalve consistencies were not significantly different both in healthy subjects (valve-averaged mean difference [limits of agreement width]: 3.2 +/- 0.8 [8.7 +/- 1.1] mL/beat for PROUD, 5.5 +/- 2.9 [13.7 +/- 2.3] mL/beat for EPI, P = 0.07) and in patients with valvular regurgitation (2.3 +/- 1.2 [15.3 +/- 5.9] mL/beat for PROUD, 0.6 +/- 0.6 [19.3 +/- 2.9] mL/beat for EPI, P = 0.47). Agreement between EPI and PROUD was higher than between 4D flow (EPI or PROUD) and 2D MRI for forward flow, stroke volumes, and regurgitant volumes. Up to R = 28 in healthy subjects and R = 14 in patients with valvular regurgitation, PROUD intervalve consistency remained comparable to that of EPI. Peak velocities and E/A ratios were preserved up to R = 9. Conclusion PROUD is comparable to EPI in terms of intervalve consistency and may be used with higher undersampling factors to shorten scan times further. Level of Evidence 1 Technical Efficacy Stage 2

Introduction Intestinal blood flow evaluation during strangulated bowel obstruction is often based on the subjective assessment of the operator. Therefore, we aimed to comprehensively determine the presence or absence of intestinal blood flow based on normal light and indocyanine green (ICG) fluorescence imaging. Moreover, we ascertained whether the chosen surgical plan was appropriate, based on the patients' postoperative course and pathological findings. Methods All 14 patients diagnosed with strangulated bowel obstruction at our hospital who underwent laparoscopic surgery between July 2019 and January 2021 were enrolled. Surgical plans were chosen based on normal light imaging combined with near-infrared imaging after intravenous ICG injection. Intestinal resection was performed via a small laparotomy if resection was considered necessary. In the intestinal resection group, the presence of intestinal necrosis was examined based on the pathological findings of the resected specimens. In the intestinal preservation group, postoperative complications, such as delayed intestinal perforation and intestinal stricture, were examined. Results Intestinal resection was performed in 4 cases. The pathological findings of the resected specimens showed necrosis of the small intestine in all cases. No intra-abdominal complication occurred any of the cases, and the median postoperative hospital stay was 9.9 days. Conclusions The selection of a surgical plan in conjunction with ICG fluorescence findings was valid in all 14 cases. ICG fluorescence imaging is useful in laparoscopic surgery for strangulated bowel obstruction and may be a novel method for evaluating intestinal blood flow during surgery.

Background Many new tools for abdominal aortic aneurysm (AAA) rupture risk evaluation have been developed. These new tools need detailed hemodynamic information in AAA. However, hemodynamic data obtained from in vivo research are lacking. Thus, the objective of this study was to analyze blood flow patterns in an in vivo AAA model to acquire real-time hemodynamic information using AneurysmFlow, a novel flow evaluation system. Methods Digital subtraction angiography images of patients who underwent endovascular aneurysm repair were analyzed using the visualization function of the AneurysmFlow to classify blood flow patterns as laminar or turbulent flow. The presence of boundary layer separation was also evaluated. The time taken for contrast medium to travel from the infrarenal aortic neck to aortic bifurcation was acquired to calculate the flow velocity. Associations between characteristics of aneurysm including lumen occupying ratio of intraluminal thrombus (ILT) and the hemodynamic flow pattern were evaluated. Results A total of 37 AAA patients was enrolled. Their blood flow patterns were evaluated using the AneurysmFlow. Logistic regression analyses with lumen occupying ratio of ILT as an independent variable showed that the larger the lumen occupying ratio of ILT, the more likely the aneurysm was to show a laminar pattern (P = 0.03) and the more likely the boundary layer separation would not exist (P = 0.04). The flow velocity from the infrarenal aortic neck to the aortic bifurcation showed a positive association with the lumen occupying ratio of the ILT in linear regression analysis (P Conclusion Hemodynamic analysis of AAA with the AneurysmFlow using real-time individual patient models showed different flow patterns and flow velocities depending on ILT. This novel analytic approach using AneurysmFlow has potential to play an important role in obtaining clinically meaningful hemodynamic information of AAA.

Item does not contain fulltext BACKGROUND: Coronary blood flow in humans is known to be predominantly diastolic. Small studies in animals and humans suggest that this is less pronounced or even reversed in the right coronary artery (RCA). AIMS: This study aimed to characterise the phasic patterns of coronary flow in the left versus right coronary arteries of patients undergoing invasive physiological assessment. METHODS: We analysed data from the Iberian-Dutch-English Collaborators (IDEAL) study. A total of 482 simultaneous pressure and flow measurements from 301 patients were included in our analysis. RESULTS: On average, coronary flow was higher in diastole both at rest and during hyperaemia in both the RCA and LCA (mean diastolic-to-systolic velocity ratio [DSVR] was, respectively, 1.85±0.70, 1.76±0.58, 1.53±0.34 and 1.58±0.43 for LCA(rest), LCA(hyp), RCA(rest) and RCA(hyp), p

Study Objective To quantitatively evaluate the blood flow in ovaries (ischemic ovaries) that underwent torsion using indocyanine green angiography (ICGA) and assess the use of ICGA as an indicator for functional preservation of the ovaries. Design In vivo animal study. Setting The University of Yamanashi Animal Experimentation Center. Subjects Eighteen female Wistar albino rats. Interventions As an alternative to ovarian torsion, we occluded an ovary in each rat for 24 hours, after which we performed ICGA before and after releasing ischemia and extracted the following 8 parameters: Fmax (maximum F value before releasing ischemia); Tmax (time taken from the onset of an increase in F to reaching Fmax); T½max (time taken from the onset of an increase in F to reaching half of Fmax); slope (Fmax/Tmax); time ratio (T½max/Tmax); F′max (maximum F value after releasing ischemia); reperfusion rate (F′max/Fmax); and reperfusion gap (F′max – Fmax). Four weeks later, we counted the total number of primordial and primary follicles and classified the rats into functional and nonfunctional groups. Measurements and Main Results On the basis of the total number of primordial and primary follicles, 13 rats had “functional” ovaries on the clamped side, and 5 rats had “nonfunctional” ovaries. The area under the curve values for each parameter were as follows: Fmax, 0.908; Tmax, 0.569; T½max, 0.546; time ratio, 0.746; slope, 0.877; F′max, 0.723; reperfusion rate, 0.938; and reperfusion gap, 0.862. Conclusion ICGA can be used to quantitatively evaluate ovaries that have been subjected to ischemia, and the magnitude of fluorescence intensity can be an excellent predictor of ovarian necrosis. Quantifying the degree of reperfusion immediately after the release of ischemia can be an equally excellent predictor of necrosis.

Carbon monoxide (CO) is the native product of organism metabolism. In biology, carbon monoxide is naturally produced by the action of heme oxygenase 1 and 2 on the heme from hemoglobin breakdown. This process produces a certain amount of carboxyhemoglobin in healthy persons, even if they do not breathe any carbon monoxide. CO functions as an endogenous signaling molecule modulates functions of the cardiovascular system, suppresses, reverses, and repairs the damage caused by inflammatory responses and may play the role of potential therapeutic agent. On the other hand, CO combines with hemoglobin to produce carboxyhemoglobin, which occupies the space in hemoglobin that normally carries oxygen, but it is ineffective for delivering oxygen to bodily tissues. Furthermore, CO also binds to other molecules, such as myoglobin and mitochondrial cytochrome oxidase. Exposures to carbon monoxide may cause significant damage to the heart and central nervous system. Thus, excessive endogenous CO production and excessive carboxyhemoglobin generation may play a significant role in tissue damage and multiorgan dysfunction formation. Apart from hemoglobin breakdown, heme compounds of cell membrane and mitochondrial enzymes may become the source of endogenous CO and carboxyhemoglobin production. Cell damage in traumatic shock and ischemia/reperfusion circumstances, tissue blood loss, blood transfusions and intensive reactive oxygen species generation can lead to foregoing events. Currently, many investigators consider an endogenous CO and carboxyhemoglobin production in critical states as a compensatory mechanism that promotes cytoprotection and contributes to patients’ survivability. We have studied the results of these investigations by means of the evaluation of CO production activity and the estimation of carboxyhemoglobin content in patient blood and СO in expiratory air. We have compared these results with the outcomes of our observation. Carboxyhemoglobin blood concentration no more than 4 % was presented in the majority of foreign investigations in patients in critical states. In our study, there have been examined patients with polytrauma with the symptoms of a wound shock at an early hospital stage. The indices of central hemodynamics and the saturation of capillary blood with oxygen, the perfusion index value have been determined according to the Masimo company techniques. All the patients were delivered to emergency department with normal carboxyhemoglobin blood concentration. Pathological carboxyhemoglobin was detected after reperfusion emergence. Fast fluid resuscitation, hypertonic solution use, epinephrine administration were associated with increase of the blood pressure, perfusion index (PI) and carboxyhemoglobin blood concentration. PI value is equal to 0.6–1.5 % in compensatory shock (I–II state severity) and associated with elevation of carboxyhemoglobin blood concentration in level 4–10 %. PI value is equal to 0.1–0.5 % in decompensatory shock (III–IV state severity) and associated with elevation of carboxyhemoglobin blood concentration in level 12–20 %. In the most severe cases, carboxyhemoglobin blood concentration increased up to 26 %. Blood reinfusion was associated with the increase of blood carboxyhemoglobin up to 10–14 %. So, endogenous CO production and carboxyhemoglobin generation in trauma with shock is strongly associated with shock state severity. The most active CO production in shock occurred in reinfusion period after capillary blood flow increased. The carboxyhemoglobin blood concentration in traumatic shock may be very increased. CO level and carboxyhemoglobin blood content in shock and reperfusion can play a significant role in hypoxia and mitochondrial dysfunction formation.

The purpose and objectives of the study: to evaluate the efficiency of traditional methods of surgical and conservative treatment of the cold injury, to set clinical, instrumental and laboratory factors determining it, to highlight the prognostic criteria. Material and methods. The study included 147 patients with frostbites (128 men and 19 women aged from 16 to 79 years). Various methods of surgery were used in 48 % of cases, 52 % of patients were treated conservatively. Results. Amputations of limbs were carried in 18 % of patients with cold injury, amputations of fingers — in 24 %, and complete preservation of the anatomical features of arms and legs were established in 59 % of the victims, and the treatment efficiency of women with frostbites was better than men, at the same time the results of therapeutic measures are worsen according to the increased age of patients. Presence of concomitant cardiovascular and respiratory disease, the degree of abnormality of blood flow in vessels, integrated changes in initial laboratory parameters (levels of protein, non-protein nitrogenous products, the parameters of blood coagulation, activity of creatine kinase in it, physicochemical values of interphase activity and viscoelasticity of serum) are negatively depend on frostbite severity, that may have prognostic value for further surgical interventions. Conclusions. The results of therapeutic measures in cold injury are closely related to the clinical and laboratory course of the pathological process, and the highlighted prognostic criteria will improve the quality of medical technology to assist these patients.

The investigations involved 290 patients (85 males and 205 females). The data of patients with non-alcoholic fatty liver disease (NAFLD) (steatosis), combined with overweight, and the data of control group patients with normal body weight without liver disease have been compared. Examined patients were divided into four age groups (according to World Health Organization criterion): 1st age group — from 25 to 34 years, 2nd — from 35 to 44 years, 3rd — from 45 to 59 years, 4th — from 60 to 75 years. Structural and hemodynamic parameters of great vessels of the neck, obtained in duplex investigation (ultrasound sonography in B-regime, color flow mapping and Doppler investigation), were analyzed. The changes of structural and hemodynamic parameters of great vessels of the neck (intima-media complex thickening, reduction in the linear velocity of blood flow) were determined. NAFLD (steatosis), associated with increased body weight, has a direct impact on the structural and hemodynamic state of great vessels of the neck. A correlation between NAFLD (steatosis), combined with increased body weight, and indicator of blood velocity — peak systolic flow velocity (p < 0.05) has been revealed.Violation of the structure and hemodynamics of the main vessels of the neck, detected during the complex duplex examination, is the result of direct impact of NAFLD (steatosis) and increased body weight and leads to the development of cardiovascular risk, mainly in groups of middle-aged and elderly patients.

C-Reactive protein and erythrocyte sedimentation rate are crucial parameters used to monitor giant cell arteritis (GCA). Given that tocilizumab is approved for the treatment of GCA, these parameters are less sensitive because of the effects of interleukin-6 receptor blockade. Thus, the optimal method for monitoring GCA patients undergoing tocilizumab therapy, especially patients exhibiting a persistent thickened vessel wall in large vessels, remains unclear. Contrast-enhanced ultrasonography (CEUS) can increase the visibility of tissue perfusion by slow blood flow, which cannot be detected by power color doppler. We used CEUS to investigate patients with active and inactive GCA of the large vessels (active large vessel arteritis [aLVV]/inactive large vessel arteritis [iLVV]) who were not administered tocilizumab in this proof-of-concept study. After injection of the ultrasound contrast agent, the contrasted area (CA) of large vessels in a transverse section was calculated twice: first when the lumen was contrasted completely and once again 4–8 s later. We investigated the value of increase in CA that exhibited the best sensitivity and specificity for aLVV. Twenty-four patients were included in this study: 15 with aLVV and 9 with iLVV. The CA increased from 32.2 ± 16.8 to 52.5 ± 21.3 mm2 (p

Objective:Neovascularization can maintain and even improve tissue perfusion in the setting of limb ischemia during peripheral artery disease. The molecular and cellular mechanisms mediating this process are incompletely understood. We investigate the potential role(s) for Id3 (inhibitor of differentiation 3) in regulating blood flow in a murine model of hindlimb ischemia (HLI).Approach and Results:HLI was modeled through femoral artery ligation and resection and blood flow recovery was quantified by laser Doppler perfusion imaging. Mice with global Id3 deletion had significantly impaired perfusion recovery at 14 and 21 days of HLI. Endothelial- or myeloid cell-specific deletion of Id3 revealed no effect on perfusion recovery while B-cell–specific knockout of Id3 (Id3BKO) revealed a significant attenuation of perfusion recovery. Flow cytometry revealed no differences in ischemia-induced T cells or myeloid cell numbers at 7 days of HLI, yet there was a significant increase in B-1b cells in Id3BKO. Consistent with these findings, ELISA (enzyme-linked immunoassay) demonstrated increases in skeletal muscle and plasma IgM. In vitro experiments demonstrated reduced proliferation and increased cell death when endothelial cells were treated with conditioned media from IgM-producing B-1b cells and tibialis anterior muscles in Id3BKOmice showed reduced density of total CD31+and αSMA+CD31+vessels.Conclusions:This study is the first to demonstrate a role for B-cell–specific Id3 in maintaining blood flow recovery during HLI. Results suggest a role for Id3 in promoting blood flow during HLI and limiting IgM-expressing B-1b cell expansion. These findings present new mechanisms to investigate in peripheral artery disease pathogenesis.

PURPOSE The purpose of the current study was to clarify the blood flow pattern in the left atrium (LA), potentially causing the formation of thrombosis after left upper lobectomy (LUL). The blood flow in the LA was evaluated and compared between LUL patients with and without thrombosis. For the evaluation, we applied highly accelerated 4D flow MRI with dual-velocity encoding (VENC) scheme, which was expected to be able to capture slow flow components in the LA accurately. METHODS Eight volunteers and 18 patients subjected to LUL underwent dual-VENC 4D Flow MRI. Eight patients had a history of thrombosis. We measured the blood flow velocity and stasis ratio (proportion in the volume that did not exceed 10 cm/s in any cardiac phase) in the LA and left superior pulmonary vein (LSPV) stump. For visual assessment, the presence of each collision of the blood flow from pulmonary veins and vortex flow in the LA were evaluated. Each acquired value was compared between healthy participants and LUL patients, and in LUL patients with and without thrombosis. RESULTS In LUL patients, blood flow velocity near the inflow part of the left superior pulmonary vein (Lt Upp) and mean velocity in the LA were lower, and stasis ratio in the LA was higher compared with healthy volunteers (Lt Upp 9.10 ± 3.09 vs.13.23 ± 14.19 cm/s, mean velocity in the LA 9.81 ± 2.49 vs. 11.40 ± 1.15 cm/s, and stasis ratio 25.28 ± 18.64 vs. 4.71 ± 3.03%, P = 0.008, 0.037, and < 0.001). There was no significant difference in any quantification values between LUL patients with and without thrombosis. For visual assessment, the thrombus formation was associated with no collision pattern (62.5% vs. 10%, P = 0.019) and not with vortex flow pattern (50% vs. 30%, P = 0.751). CONCLUSION The net blood flow velocity was not associated with the thrombus formation. In contrast, a specific blood flow pattern, the absence of blood flow collision from pulmonary veins, correlates to the thrombus formation in the LA.

INTRODUCTION This study aimed to investigate the effects of the strong occlusal force on the hemodynamics of gingival microcirculation. METHODS Eleven adult volunteers with healthy periodontium and normal occlusion participated in this study. Using a noncontact laser Doppler flowmeter placed at the attached gingiva and the interdental papilla of the maxillary first premolar, changes in gingival blood flow (GBF) were examined during and after clenching. RESULTS When the strong occlusal pressure was applied on the maxillary first premolar by clenching, GBF in the attached gingiva on the buccal side decreased significantly compared with the resting GBF, with medians of 2.3 mL/min/100 g and 5.4 mL/min/100 g, respectively (P

The brain's vascular network dynamically affects its development and core functions. It rapidly responds to abnormal conditions by adjusting properties of the network, aiding stabilization and regulation of brain activities. Tracking prominent arterial changes has clear clinical and surgical advantages. However, the arterial network functions as a system; thus, local changes may imply global compensatory effects that could impact the dynamic progression of a disease. We developed automated personalized system-level analysis methods of the compensatory arterial changes and mean blood flow behavior from a patient's clinical images. By applying our approach to data from a patient with aggressive brain cancer compared with healthy individuals, we found unique spatiotemporal patterns of the arterial network that could assist in predicting the evolution of glioblastoma over time. Our personalized approach provides a valuable analysis tool that could augment current clinical assessments of the progression of glioblastoma and other neurological disorders affecting the brain.

Superb microvascular imaging (SMI) is a new Doppler method that enables the visualization of low-velocity blood flow. The aim of the study described here was to clarify whether SMI can detect prenatal pathological findings in pathologic placentas. In this prospective diagnostic observational study, pregnant women who were admitted to our center for perinatal management were enrolled. Ultrasound examinations to identify placental pathologies using SMI were performed before delivery. After delivery, the placental tissue was clipped for microscopic examination at locations determined under ultrasound guidance. The accuracy of prenatal ultrasound detection of placental pathologies was compared between women who were admitted because of fetal growth restriction (FGR), pre-eclampsia and other indications. The highest accuracy was observed with placental infarction in FGR (positive predictive value = 100%, sensitivity = 89%, area under the curve = 0.945). As a result, it became clear that SMI can accurately detect placental pathologic findings, such as placental infarction and avascular villi. This modality may improve perinatal management in cases of placental dysfunction.

Background Contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS) can be used for the differential diagnosis of pancreatic lesions by evaluating microvascular circulation and patterns of contrast enhancement. However, routine use of CEH-EUS is limited by its high cost, the lack of contrast agent availability and the absence of expertise with this technique. Directional eFLOW (D-eFLOW) (Aloka Co., Ltd., Tokyo, Japan) was introduced as a new high-definition modality that detects blood flow in microvessels. Because it uses built-in functions, it entails no additional cost and reduces time for examination. The present study compared the usefulness of D-eFLOW and CEH-EUS for differential diagnosis of pancreatic and peripancreatic lesions. Methods This retrospective study analyzed 130 patients who underwent EUS and D-eFLOW examinations from January 2016 to March 2020 to evaluate pancreatic and peripancreatic masses. Results All 130 patients underwent D-eFLOW and CEH-EUS examinations. Histological diagnoses were confirmed in 130 patients by EUS-FNA and/or surgery. D-eFLOW and CEH-EUS showed good correlation in evaluating the vascularity of pancreatic and peripancreatic tumors (Fisher's exact test, p Conclusions In evaluating the characteristics of tumorous lesions, vascularity detected by D-eFLOW showed good correlation with enhancement patterns of CEH-EUS. D-eFLOW can be considered a good alternative to CEH-EUS in diagnosing pancreatic and peripancreatic masses.

OBJECTIVE: Cardiac surgery utilizing circulatory arrest is most commonly performed under deep hypothermia (~18°C) to suppress tissue oxygen demand and provide neuroprotection during operative circulatory arrest. Studies investigating the effects of deep hypothermic circulatory arrest (DHCA) on neurodevelopmental outcomes of patients with congenital heart disease give conflicting results. Here, we address these issues by quantifying changes in cerebral oxygen saturation, blood flow, and oxygen metabolism in neonates during DHCA and investigating the association of these changes with post-operative brain injury. METHODS: Neonates with critical congenital heart disease undergoing DHCA were recruited for continuous intraoperative monitoring of cerebral oxygen saturation (ScO(2)) and an index of cerebral blood flow (CBF(i)) using two non-invasive optical techniques, diffuse optical spectroscopy (DOS) and diffuse correlation spectroscopy (DCS). Pre- and post-operative brain magnetic resonance imaging (MRI) was performed to detect white matter injury (WMI). RESULTS: Fifteen neonates were studied, and 11/15 underwent brain MRI. During DHCA, ScO(2) decreased exponentially in time with a median decay rate of −0.04 min(−1). This decay rate was highly variable between subjects. Subjects who had larger decreases in ScO(2) during DHCA were more likely to have post-operative WMI (p=0.02). CONCLUSIONS: Cerebral oxygen extraction persists during DHCA and varies widely from patient-to-patient. Patients with a higher degree of oxygen extraction during DHCA were more likely to show new WMI in post-operative MRI. These findings suggest cerebral oxygen extraction should be monitored during DHCA to identify patients at risk for hypoxic-ischemic injury, and that current commercial cerebral oximeters may underestimate cerebral oxygen extraction.

PURPOSE In aortic stenosis (AS), the discrepancy between moderately accelerated flow and effective orifice area (EOA) continues to pose a challenge. We developed a method of measuring the vena contracta area as hemodynamic EOA using cardiac MRI focusing on AS patients with a moderately accelerated flow to solve the problem that AS severity can currently be determined only by echocardiography. METHODS We investigated 40 patients with a peak transvalvular velocity > 3.0 m/s on transthoracic echocardiography (TTE). The patients were divided into highly accelerated and moderately accelerated AS groups according to whether or not the peak transvalvular velocity was ≥ 4.0 m/s. From the multislice 2D cine phase-contrast MRI data, the cross-sectional area of the vena contracta of the reconstructed streamline in the Valsalva sinus was defined as MRI-EOAs. Patient symptoms and echocardiography data, including EOA (defined as TTE-EOA), were derived from the continuity equation using TTE. RESULTS All participants in the highly accelerated AS group (n = 19) showed a peak velocity ≥ 4.0 m/s in MRI. Eleven patients in the moderately accelerated AS group (n = 21) had a TTE-EOA < 1.00 cm2. In the moderately accelerated AS group, MRI-EOAs demonstrated a strong correlation with TTE-EOAs (r = 0.76, P < 0.01). Meanwhile, in the highly accelerated AS group, MRI-EOAs demonstrated positivity but a moderate correlation with TTE-EOAs (r = 0.63, P = 0.004). MRI-EOAs were overestimated compared to TTE-EOAs. In terms of the moderately accelerated AS group, the best cut-off value for MRI-EOAs was < 1.23 cm2, compatible with TTE-EOAs < 1.00 cm2, with an excellent prediction of the New York Heart Association classification ≥ III (sensitivity 87.5%, specificity 76.9%). CONCLUSION MRI-EOAs may be an alternative to conventional echocardiography for patients with moderately accelerated AS, especially those with discordant echocardiographic parameters.

Fetal experience forms the basis for postnatal life. This relationship may be obvious in the newborn infant, although it is sometimes not apparent until later in development. One fetal condition with known implications for later life is intrauterine growth restriction (IUGR), which ranges from being an important factor in perinatal mortality to affecting morbidity in adulthood.

OBJECTIVE: To cure atrial fibrillation, the maximum ablation depth (⩾ 50∘C) should exceed the myocardial thickness to achieve the effect of transmural ablation. The blood flow of pulmonary vein in the endocardium can cause the change in the myocardial temperature distribution. Therefore, the study investigated the effect of different pulmonary vein blood flow velocities on the endocardial microwave ablation. METHODS: The finite element model of the endocardial microwave ablation of pulmonary vein was simulated by electromagnetic thermal flow coupling. The ablation power was 30 W and the ablation time was within 30 s. The blood flow in the coupling of fluid mechanics equation and heat transfer equation results in the heat damage. Furthermore, the cause of the different lesion dimensions is the blood flow velocity. The flow velocities were set as 0, 0.02, 0.05, 0.07, 0.12, 0.16, 0.20, 0.25 and 0.30 m/s. RESULTS: When the flow velocities were 0, 0.02, 0.05, 0.07, 0.12, 0.16, 0.20, 0.25 and 0.30 m/s, the maximum ablation depth were 6.00, 5.56, 5.16, 5.12, 5.04, 5.01, 4.98, 4.96 and 4.94 mm, respectively; the maximum ablation width were 12.53, 9.63, 9.23, 9.16, 9.07, 9.05, 8.94, 8.91 and 8.90 mm, respectively; the maximum ablation length were 12.00, 11.61, 8.98, 8.59, 8.37, 8.23, 8.16, 8.06 and 8.04 mm respectively. To achieve transmural ablation, the time was 3, 3, 3, 3, 3, 4, 4, 4, 4 s, respectively when the myocardial thickness was 2 mm; the time was 7, 8, 8, 8, 9, 9, 9, 9, 9 s, respectively when 3 mm; the time was 15, 16, 18, 19, 19, 20, 20, 20, 20 s, respectively when 4 mm. CONCLUSIONS: When the velocity increases from 0 m/s to 0.3 m/s, the microwave lesion depth decreases by 1.06 mm. To achieve transmural ablation, when the myocardial thickness is 2 mm, 3 and 4 s should be taken when the velocity is 0–0.12 and 0.12–0.30 m/s, respectively; when the myocardial thickness is 3 mm, 7, 8 and 9 s should be taken when 0, 0–0.07 and 0.07–0.30 m/s respectively; when the myocardial thickness is 4 mm, 15, 16, 18, 19, 20 s should be taken when 0, 0–0.02, 0.02–0.05, 0.05–0.12, 0.12 m/s–0.30 m/s.

BACKGROUND: Negative pressure wound therapy (NPWT) has been established over years for treatment of chronic and complex wounds. OBJECTIVE: Aim of this study was to investigate the effect NPWT on the microperfusion. METHODS: Prospective single centre analysis of patients treated with NPWT due to acute (ACUTE) wounds after fasciotomy or patients with chronic wounds (CHRONIC) due to a chronic limb threatening ischemia was performed. NPWT was conducted through a three days sequence with a negative pressure of –120 mmHg. Before after and during the entire period of therapy the microperfusion was assessed (O2C™, LEA Medizintechnik). RESULTS: Comparison of the perfusion values of 28 patients (CHRONIC/ACUTE 5/23, women/men 8/20) before and after the NPWT sequence showed a non-significant improvement in the CHRONIC group (supine position: p = 0.144, elevated position p = 0.068) and a significant decrease in the ACUTE group (supine position p = 0.012, elevated position p = 0.034). This effect could also been demonstrated during the NPWT over time (CHRONIC: supine position: p = 0.320, elevated position: p = 0.053, ACUTE: supine position: p = 0.021, elevated position: p = 0.012). CONCLUSION: Microperfusion measurements showed alterations and differences in wound bed perfusion of acute and chronic wounds; acute wounds tended to a decrease of blood flow, whereas this effect was not seen in chronic wounds in peripheral artery disease.

Nociceptive input diminishes recovery and increases lesion area after a spinal cord injury (SCI). Recent work has linked these effects to the expansion of hemorrhage at the site of injury. The current paper examines whether these adverse effects are linked to a pain-induced rise in blood pressure and/or flow. Male rats with a low-thoracic spinal cord injury were treated with noxious input [electrical stimulation (shock) or capsaicin] soon after injury. Locomotor recovery and blood pressure were assessed throughout. Tissues were collected three hours, 24 hours, or 21 days later. Both electrical stimulation and capsaicin undermined locomotor function and increased the area of hemorrhage. Changes in blood pressure/flow varied depending on type of noxious input, with only shock producing changes in blood pressure. Providing behavioral control over the termination of noxious stimulation attenuated the rise in blood pressure and hemorrhage. Pretreatment with the alpha-1 adrenergic receptor inverse agonist, prazosin, reduced the stimulation-induced rise in blood pressure and hemorrhage. Prazosin also attenuated the adverse effect noxious stimulation has on long-term recovery. Administration of the adrenergic agonist, norepinephrine, a day after injury induced an increase in blood pressure and disrupted locomotor function, but had little effect on hemorrhage. Further, inducing a rise in blood pressure/flow using norepinephrine undermined long-term recovery and increased tissue loss. Mediational analyses suggest that the pain-induced rise in blood flow may foster hemorrhage after SCI. Increased blood pressure appears to act through an independent process to adversely affect locomotor performance, tissue sparing, and long-term recovery.

Background and objective Arteriovenous Fistula (AVF) is an essential requirement in Hemodialysis (HD) to remove toxins and excess fluid from the blood of patients with Chronic Renal Failure (CRF). The Blood Flow Rate (BFR) in AVF is an important factor in the success of HD. Due to a lack of studies of low BFR during HD, this study was conducted. The objective of this study was to compare the success rate of HD in patients with a BFR = 400-500 mL min-1 (group-2), in comparison to those of higher BFR (group-1). Materials and methods This prospective cohort study was conducted at the ultrasound Doppler (USD) unit in King Fahad Hospital in Almadinah from July to December, 2019. In this study, 44 patients underwent AVF for HD and were assessed by USD for 2 consecutive visits at 3 months intervals. The success rate of HD was measured in patients with a BFR = 400-500 mL min-1 and in those with BFR>500 mL min-1. A comparison of the success rate in the 2 groups was done. Results Among the 44 patients, 59% were males and 41% were females. The age of participants ranged from 20-80 years (mean: 46.75±13.67 years). The patients underwent HD 3 or 2 session's week-1 for 3 or 4 hrs (mean 3.84±0.36 h) per session. In the first assessment, the success rate was 100% in both groups but it was 88.24% in group-1 and 70% in group-2 in the second assessment. Conclusion The success rate of hemodialysis in patients with BFR 400-500 mL min-1 in AVF was acceptable in comparison to that in patients with BFR>500 mL min-1.

BACKGROUND Although rates of microvascular thrombosis following free-flap breast reconstruction are low, debate persists about the optimal methods to restore blood flow and prevent ensuing flap shrinkage or fibrosis. Here we evaluate our management of microvascular compromise, including both a review of our approach for restoring blood flow and addressing the ensuing inflammatory changes following ischemia reperfusion. METHODS We conducted a retrospective review of autologous free tissue transfer breast reconstructions from 1/2010 to 1/2020. Patients who had flaps requiring take-back for salvage were identified. Management of microvascular compromise and ischemia reperfusion injury were recorded. RESULTS Of 2103 flaps were used in the breast reconstructions, 47 flaps required take-back for microvascular compromise (2.2%). Most flaps were either completely salvaged (n = 29, 61.7%) or partially salvaged (n = 5, 10.6%). Thirteen (27.7%) were a total flap loss, for an overall rate of 0.8% (including 3 flaps with no salvage attempt). Management of microvascular compromise most often included revision of the anastomosis (n = 33, 70.2%), thrombectomy (n = 27, 57.4%), tissue plasminogen activator administration (n = 26, 55.3%), and vein grafts (n = 18, 38.3%). Management of ischemia reperfusion included intraoperative steroids (n = 33, 70.2%), postoperative steroids (n = 17, 38.6%), and postoperative therapeutic anticoagulation (n = 27, 61.3%). Of 34 salvaged flaps, 5 (14.7%) had partial flap loss and/or fat necrosis on clinical examination at an average follow-up of 2.7 ± 2.8 years. CONCLUSIONS Salvage of microvascular compromise in autologous breast reconstruction should include restoration of blood flow and management of ischemia reperfusion injury. Attention to both is paramount for successful outcomes.

Myocardial flow reserve represents the ratio of myocardial blood flow between stress and rest, giving functional information about both macrocirculation and microcirculation; it has been reported extensively in positron emission tomography, with an increase in diagnostic performance, providing important prognostic information and being a powerful tool to guide therapy. Advances in single photon emission computed tomography, with the widespread availability of "cadmium zinc telluride" single photon emission computed tomography cameras, raise the question of myocardial flow reserve use in daily clinical practice. In this article, we review the pathophysiology of myocardial blood flow and myocardial flow reserve, and the initial data available from single photon emission computed tomography myocardial blood flow and myocardial flow reserve evaluation; we also discuss potential limitations to the wider implementation of flow evaluation in single photon emission computed tomography.

Summary Despite the fact that door-to-balloon times have been greatly reduced, the rates of death and the incidence of heart failure in patients with ST-segment elevation myocardial infarction (MI) have plateaued. There is still an unmet need to further reduce MI size in the reperfusion era. Most adjunctive therapies to enhance myocardial salvage have failed, but some have shown promise. Currently, the only adjunctive therapy in a pivotal trial that has demonstrated reductions in infarct size is localized delivery of supersaturated oxygen (SSO2) therapy. This review provides background on prior infarct size reduction efforts. The authors describe the preclinical data that shows the effectiveness of SSO2 in reducing MI size, improving regional myocardial blood flow and cardiac function, and reducing adverse left ventricular remodeling—presumably by reducing patchy areas of residual ischemia within the reperfused risk zone. Potential mechanisms by which SSO2 is beneficial are described, including the delivery of high levels of dissolved oxygen through plasma to ischemic, but viable, vascular and myocardial cells, thus allowing their survival and function. The authors then describe the SSO2 clinical trials, demonstrating that in patients with anterior ST-segment elevation MI, SSO2 therapy safely and effectively reduces infarct size, improves cardiac function, and reduces adverse left ventricular remodeling.

PURPOSE Leaflet thrombosis is a significant adverse event after transcatheter aortic valve (TAV) replacement (TAVR). The purpose of our study was to present a semi-empirical, mathematical model that links patient-specific anatomic, valve, and flow parameters to predict likelihood of leaflet thrombosis. METHODS The two main energy sources of neo-sinus (NS) washout after TAVR include the jet flow downstream of the TAV and NS geometric change in volume due to the leaflets opening and closing. Both are highly dependent on patient anatomic and hemodynamic factors. As rotation of blood flow is prevalent in both the sinus of Valsalva and then the NS, we adopted the vorticity flux or circulation (Г) as a metric quantifying overall washout. Leaflet thrombus volumes were segmented based on hypo-attenuating leaflet thickening (HALT) in post-TAVR patient's gated computed tomography. Г was assessed using dimensional scaling as well as computational fluid dynamics (CFD) respectively and correlated to the thrombosis volumes using sensitivity and specificity analysis. RESULTS Г in the NS, that accounted for patient flow and anatomic conditions derived from scaling arguments significantly better predicted the occurrence of leaflet thrombus than CFD derived measures such as stasis volumes or wall shear stress. Given results from the six patient datasets considered herein, a threshold Г value of 28.0 yielded a sensitivity and specificity of 100% where patients with Gamma < 28 developed valve thrombosis. A 10% error in measurements of all variables can bring the sensitivity specificity down to 87%. CONCLUSION A predictive model relating likelihood of valve thrombosis using Г in the NS was developed with promising sensitivity and specificity. With further studies and improvements, this predictive technology may lead to alerting physicians on the risk for thrombus formation following TAVR.

The heart is one of the most important organs of the human body. It circulates blood throughout the human body and delivers oxygen and nutrients to all the organs for metabolism. Cardiac muscle contraction results in blood circulation, which maintains the body temperature at approximately 37 °C. If the cardiac function is abnormal, then the body temperature will be affected. The cardiac function degenerates as the human body ages, and the degeneration can occasionally result in cardiovascular diseases. When the Internet of Medical Things is integrated into heart disease screening systems to detect heart diseases, people can perform self-examinations to evaluate whether their hearts exhibit irregularities for early heart disease detection. STM32 is used in this study as the main Internet-of-Medical Things controller and is combined with the Internet of Things devices—a sphygmomanometer cuff, temperature sensor, and pulse sensor—for instrument control and data acquisition. This assembly is used to develop a valvular heart disease screening system, whose structure incorporates deep learning for the development of fitting models and analysis. An experiment is performed where blood flow is blocked temporarily and released to observe changes in the surface temperature of the fingertip skin, and the blood supply capability of the heart is assessed indirectly based on the temperature change curve. Eighteen subjects were recruited in the experiment, where one subject exhibited cardiac valve insufficiency and arrhythmia. In the experiment, temperature curve variation data are successfully obtained from the healthy subjects, whereas the temperature curve irregularities of the patient with cardiac valve insufficiency are identified. This subject’s temperature range throughout three test steps is smaller by within 0.52 °C compared with those of most of the other subjects. In addition, during blood blocking and release, the overall temperature curve decreases, whereas some curves escalate first before plummeting slowly. The data analysis results show that the temperature curve variation and values of Subject 2 are similar to those of Subject 10, suggesting the incidence of valvular heart disease. This valvular heart disease screening system can successfully analyze and assess the characteristic signal values of patients with valvular heart disease.

A 4-year-old boy with left intralobar pulmonary sequestration associated with left main coronary artery obstruction (LMCAO) and severe mitral regurgitation (MR) was admitted to our hospital. Since the patient presented with dyskinesia of the cardiac apex and increased left ventricular end-diastolic volume (LVEDV), left main coronary artery reconstruction and mitral annuloplasty were performed. The enlargement of the left ventricle was improved after sequential surgeries. There was a risk of deterioration of MR and regrowth of LVEDV due to shunt blood flow; therefore, left lower lobectomy and aberrant artery division were performed. This is a very rare case of a patient with pulmonary sequestration associated with LMCAO and severe MR.

BACKGROUND In patients with knee osteoarthritis (KOA), the descending genicular artery (DGA) showed abnormal angiogenesis. However, the non-invasive assessment method of DGA remains unclear. The aim of this study was to clarify the characteristics of blood flow velocity of the DGA in patients with KOA and to examine the factors involved in the changes. METHODS The KOA group included 22 knees of 22 patients with KOA (4 males, 18 females; mean age, 72.3 ± 7.5 years) and the control group included 22 knees (4 males, 18 females; mean age, 71.3 ± 5.4 years) of 22 healthy adults. The peak systolic blood flow velocity (PSV) in each group was measured using ultrasonography. The KOA group was classified into the effusion group and the non-effusion group based on observed effusion, and the PSV was compared between the two groups. The relationships between PSV and suprapatellar bursa intracavitary distance, pain, femorotibial angle, Japanese Knee Osteoarthritis Measure were also investigated. RESULTS The PSV in the KOA group (51.5 ± 12.9 cm/s) was significantly higher than that in the control group (29.3 ± 4.4 cm/s) (P

Little is known about the mechanisms of aging on vascular beds and its relationship with tetra and di-hydrobiopterin (BH4 and BH2) levels. This observational clinical study analyzed the impact of aging on plasma and platelet biopterins, cutaneous blood flow (CBF), and coronary flow reserve (CFR) in healthy adults. The study enrolled healthy adults in 3 age groups: 18–30, 50–59, and 60–70 years (n = 25/group). Biopterins were assessed by LC-MS/MS using newly defined pre-analytical conditions limiting BH4 oxidation and improving long-term stability. CBF was measured by Laser Speckle Contrast Imaging coupled with acetylcholine-iontophoresis and CFR by adenosine stress cardiac magnetic resonance. In healthy adults, aging (60–70 years vs 18–30 years) significantly increased platelet BH2 (+75%, P = 0.033) and BH2 + BH4 (+31%, P = 0.033), and to a lesser extent plasma BH2 (+29%, P = 0.009) without affecting BH4 and BH4/BH2. Simultaneously, CBF was decreased (-23%, P = 0.004) but not CFR, CBF being inversely correlated with platelet BH2 (r = -0.42, P = 0.001) and BH2 + BH4 (r = -0.41, P = 0.002). The proportion of adults with abnormal platelet BH2 increased with age (+28% in 60-70y). These abnormal BH2 levels were significantly associated with reduced CBF and CFR (-16%, P = 0.03 and -26%, P = 0.02). In conclusion, our study showed that age-related peripheral endothelial dysfunction was associated with an increase in circulating BH2 without decreasing BH4, the effect being more marked in platelets, the most relevant blood compartment to assess biopterin bioavailability. Peripheral but not coronary vascular function is progressively impaired with aging in healthy adults. All these findings support biopterins as therapeutic targets to improve vascular function.

Background: Fractional flow reserve (FFR) is a gold standard to assess the impact of stenosis on the blood flow. The FFR method enhances diagnostic accuracy, lessens the need for stenting, and reduces costs. However, FFR is used in less than 10% of percutaneous coronary intervention (PCI) procedures because it needs pressure wires to measure the distal and proximal pressures and adenosine to create hyperemic conditions. Pressure-wire-based FFR measurement is, therefore, expensive and invasive. Objective: This study aims to introduce a new approach on the basis of 3D coronary angiography and the Thrombolysis in Myocardial Infarction (TIMI) frame count for fast computation of FFR in patients with coronary artery disease. Material and Methods: In this simulation study, we herein introduce Non-Invasive Flow Ratio drawing upon CFD to measure FFR based on coronary angiography images with less run time. In this study, 3D geometry was created based on coronary angiography images. The mean volumetric flow rate was calculated using the TIMI frame count. FFR calculated based on CFD was compared with pressure-wire-based FFR and NiFR was calculated in 85 patients. Results: The NiFR (r = 0.738, P< 0.001) exhibited a strong correlation with pressure-wire-based FFR. The result indicated that FFR was higher than 0.8 in the arteries with non-signif­icant stenosis and lower than 0.8 in the arter­ies with significant stenosis. Conclusion: The computational simulation of FFR and hemodynamic parameters such as pressure drop is a safe, efficient, and cost-effective method to evaluate the severity of coronary stenosis.

Aims The management of heart failure (HF) in young children is challenging. The present study aimed to clarify the effect of left univentricular epicardial pacing on dilated cardiomyopathy with left bundle branch block (LBBB) in children. Methods and results A total of five cases (30.86 ± 16.39 months, three female) of children weighing 5.8–15 kg with dilated cardiomyopathy and LBBB were included in this study. LBBB in one child occurred after device closure of peri‐membranous ventricular septal defects, and the remaining four were idiopathically discovered early after birth. Before implantation, all children suffered from refractory HF and cardiac dilatation; the left ventricular ejection fraction was 33.48 ± 5.84% with Ross Heart Failure Classification III–IV. Electrical and mechanical dyssynchrony were observed in all children with QRS duration >140 ms and prolonged septal‐to‐left posterior wall motion delay. Left univentricular epicardial pacing was successfully implanted via left axillary minithoracotomy in the five children. Sensed atrioventricular delays (83 ± 15 ms) were optimized by velocity time integral of aortic blood flow before discharge. During the follow‐up period (10.8 ± 2.68 months), the dilated failing heart was reversed significantly in terms of decreased left ventricular dimension (55.62 ± 3.46 vs. 38.94 ± 3.69 mm, P = 0.005), while the left ventricular ejection fraction improved to 60.18 ± 8.78% (P = 0.006). Conclusions In young children with low body weight, if HF is caused by or related to LBBB, left ventricular epicardial pacing still has an excellent effect.

BACKGROUND The impact of the striking perinatal circulatory changes on blood flow distribution have not to date been well examined in hypoplastic left heart syndrome (HLHS). This study aimed to document perinatal redistribution of cardiac output in HLHS compared with healthy control subjects, to further understand the impact of the perinatal transition on cerebral and systemic blood flow. METHODS Prospectively recruited HLHS case subjects (n = 31) and healthy control subjects (n = 19) underwent serial echocardiography from late fetal stages to 96 hours after birth. Combined cardiac output (CCO), systemic, pulmonary, cerebrovascular, and splanchnic flow data were compared between neonates with HLHS and control subjects, and the impact of vasoactive support and positive pressure ventilation in HLHS patients was examined. RESULTS In late gestation, CCO was similar between HLHS and control subjects, whereas middle cerebral artery (MCA) pulsatility index (PI) in HLHS was consistent with low cerebral vascular resistance. In the 96 hours after birth, CCO and pulmonary blood flow progressively increased in HLHS compared with control subjects (P < 0.001), and CCO was further increased in neonates with HLHS receiving vasoactive support (P = 0.01). Neonates with HLHS had reduced systemic and 6-24-hour superior vena cava (SVC) flow compared with control subjects (P < 0.001). Low systemic flow was further suggested by increased MCA and celiac artery PI at 6-48 hours in neonates with HLHS (P < 0.001). Systemic and SVC flow did not differ between those with and without vasoactive support. CONCLUSIONS We provide quantitative echocardiographic evidence associating impaired cerebral and systemic blood flow with perinatal hemodynamic changes in the preoperative neonate with HLHS.

This article explicates the blood flow across an artery with multiple stenosis at outer wall and a thrombus at the centre. The symmetric multiple stenosis and non-symmetric multiple stenosis shapes are both considered in this study. Entropy analysis is also taken into account for a detailed study of irreversibility. The governing equations are interpreted with provided boundary conditions and exact mathematical solutions are developed. Further, these exact solutions are elucidated graphically. Streamlines show that the closed contours are symmetric in shape for symmetric multiple stenosis but non-symmetric in shape for non-symmetric multiple stenosis shape. The increase in multiple stenosis heights, increases the shear stress at wall having multiple stenosis.

Цукровий діабет (ЦД) у світі визнано однією з найбільш важливих неінфекційних хвороб, поширення якої набуло характеру пандемії. У переліку пізніх ускладнень ЦД лідирує синдром діабетичної стопи, призводячи до ранньої інвалідизації та визначаючи високий рівень летальності. За даними Міжнародної діабетичної федерації, від 25 до 47 % госпіталізацій хворих на ЦД пов’язано з гнійно-деструктивними ураженнями стоп унаслідок розвитку хронічної ішемії тканин. В огляді відображені основні патофізіологічні механізми виникнення порушення мікроциркуляції при синдромі діабетичної стопи, що призводять до виникнення критичної ішемії нижніх кінцівок.

The retinal tissue is highly metabolically active and is responsible for translating the visual stimuli into electrical signals to be delivered to the brain. A complex vascular structure ensures an adequate supply of blood and oxygen, which is essential for the function and survival of the retinal tissue. To date, a complete understanding of the configuration of the retinal vascular structures is still lacking. Optical coherence tomography angiography has made available a huge amount of imaging data regarding the main retinal capillary plexuses, namely the superficial capillary plexuses (SCP), intermediate capillary plexuses (ICP) and deep capillary plexuses (DCP). However, the interpretation of these data is still controversial. In particular, the question of whether the three capillary plexuses are connected in series or in parallel remains a matter of debate. In this work, we address this question by utilizing a multi-scale/multi-physics mathematical model to quantify the impact of the two hypothesized vascular configurations on retinal hemodynamics and oxygenation. The response to central retinal vein occlusion (CRVO) and intraocular pressure (IOP) elevation is also simulated depending on whether the capillary plexuses are connected in series or in parallel. The simulation results show the following: (i) in the in series configuration, the plexuses exhibit a differential response, with DCP and ICP experiencing larger pressure drops than SCP; and (ii) in the in parallel configuration, the blood flow redistributes uniformly in the three plexuses. The different vascular configurations show different responses also in terms of oxygen profiles: (i) in the in series configuration, the outer nuclear layer, outer plexiform layer and inner nuclear layer (INL) are those most affected by CRVO and IOP elevation; and (ii) in the in parallel configuration the INL and ganglion cell layer are those most affected. The in series results are consistent with studies on paracentral acute middle maculopathy, secondary to CRVO and with studies on IOP elevation, in which DCP and ICP and the retinal tissues surrounding them are those most affected by ischemia. These findings seem to suggest that the in series configuration better describes the physiology of the vascular retinal capillary network in health and disease.

Gustilo–Anderson type IIIB and IIIC open fractures of the lower extremities require reconstruction of extensively injured soft tissues using a free flap; however, impaired blood flow through the flap is an early postoperative complication. To detect flap congestion due to venous thrombosis, blood glucose and lactate level measurements within the flap are taken to determine variations in these levels. We aimed to detect early-stage venous congestion and to perform salvage operations. We included 22 limbs with lower leg and foot open fractures, with fracture sites covered using a free flap. A pinprick test was used to measure blood glucose and lactate levels. Of 7 and 15 congested and non-congested limbs, respectively, the 7 congested limbs had a mean flap blood glucose level immediately before salvage surgery of 3.8 ± 2.0 (7.4–1.8) mmol/L. The ratio to blood glucose levels in healthy fingertips was 0.6 ± 0.2 (0.8–0.3). Lactate levels increased to 13.3 ± 5.1 (9.4–22.8) mmol/L. The ratio of blood glucose levels in congested flaps and in healthy fingertips was significantly lower than that in non-congested flaps and in healthy fingertips (p = 0.0016). Lactate levels were significantly higher in patients with congestion (p = 0.0013). Salvage surgery was performed, thrombi were removed, and six limb flaps were viable. Flap blood glucose and lactate levels provide a quantitative method of evaluating blood flow and detecting flow abnormalities postoperatively, and are useful in detecting early congestion due to venous thrombosis.

Objective: improving the algorithm for the management of patients with viral hepatitis using contrast-free arterial spin labelling (ASL) magnetic resonance (MR) perfusion.Material and methods. A total of 116 patients with viral hepatitis (VH) B, C and B + C were examined on the basis of Clinical hospital No. 1 (Smolensk): 75 (64.7%) men and 41 (35.3%) women, mean age 49.7 ± 2.3 years. The patients underwent instrumental diagnostic methods: ultrasound, clinical elastography, contrast-free hepatic ASL MR perfusion. Liver biopsy (n = 57) was used as the reference method.Results. The results of ASL MR perfusion had a high correlation with the data of clinical elastography in the diagnosis of fibrotic process; the diagnostic and prognostic significance of ASL liver perfusion in the diagnosis of fibrotic process was: AUROC 0.943 (95% CI, 0.884–0.953). There was a high correlation between ASL MR perfusion with Doppler ultrasound of hepatic blood vessels in the diagnosis of arterial blood flow disorders, but in VH В + C and cirrhosis – diagnostic and prognostic significance of the method: AUROC 0.951 (95% CI 0.932–0.972).Conclusion. ASL MR perfusion in VH patients allows to predict fibrotic changes in the hepatic parenchyma (AUROC 0.934 (95% CI 0.845–0.957)), provides information about changes in blood flow in the parenchymal structure (p < 0.005). The algorithm for the examination of VH patients should include contrast-free ASL MR perfusion at admission (AUROC 0.865 (95% CI 0.843–0.928)) and in dynamic follow-up (AUROC 0.915 (95% CI 0.881–0.946)).

Background:Preoperative chemotherapy or chemoradiotherapy is a common strategy for treating pancreatic ductal adenocarcinoma (PDAC). This study aimed to assess the association between the therapeutic response in PDAC and tumor blood circulation., Methods:The medical records of patients who underwent chemotherapy or chemoradiotherapy prior to pancreatectomy for PDAC were reviewed. Of these, patient data that included three-phase contrast-enhanced computed tomography (CECT) findings before treatments were used in this study. We evaluated the estimated tumor blood flow (eTBF) using CECT. According to the therapeutic histopathological response defined by the Evans classification, patients were divided into poor (grade I/IIa) and good (grade IIb/III/IV) responder groups. The variables, including eTBF, were compared between the two groups., Results:Thirty patients were enrolled in this study. Of these, 13 (43.3%) (grade IIB/III/IV: 8/4/1 patients) were categorized into the good responder group and 17 patients (56.7%) (grade I/IIA: 4/13 patients) were categorized into the poor responder group. eTBF was significantly higher in the good responder group (0.39 s-1 vs. 0.32 s-1, p = 0.007). An eTBF ≥ 0.36 s-1 was found to be an independent predictive factor for the destruction of over 50% of tumor cells (p = 0.036; odds ratio, 9.71; 95% confidence interval, 1.16-81.30)., Conclusions:eTBF can be used to predict the therapeutic histopathological response in PDAC prior to treatment.

Background. To compare the diagnostic value of serum markers human epididymal protein 4 (HE4) and cyclooxygenase-1 (COX-1) combined with transvaginal color Doppler sonography (TVCDS) in ovarian cancer (OC) treated with Bushen Yiqi Quyu prescription. Methods. A total of 232 OC patients treated at the hospital from January 2018 to October 2020 were randomly divided into an observation group (n = 116) and control group (n = 116). The control group was treated with essential Western medication, and the observation group was treated with essential Western medication and Bushen Yiqi Quyu prescription. The clinical efficacy of the two groups was compared. The levels of HE4 and COX-1 were compared between the two groups before and after treatment. The ultrasonic features of TVCDS were compared between the two groups before and after treatment. The ROC curve was drawn to compare the sensitivity, specificity, and accuracy of single and combined detection of HE4, COX-1, and TVCDS in the observation group. Results. The total effective rate of the observation group was significantly higher than that of the control group. After treatment, HE4 and COX-1 levels in both groups were considerably lower than those before treatment, and in the observation group, they decreased significantly than in the control group. HE4 and COX-1 were positively correlated with the clinical stage of OC. The higher the clinical stage, the higher the levels of HE4 and COX-1. After treatment, there was no significant difference in tumor location and the boundary between the two groups. There were statistically significant differences in tumor echo, nature, morphology, calcification, internal blood flow, and lymph node metastasis, and the difference in the observation group was more evident than in control group. The sensitivity, specificity, accuracy, positive detection rate, and negative detection rate of combined detection were higher than those of single detection. Conclusions. Bushen Yiqi Quyu prescription has certain curative effects in the treatment of OC patients, which can significantly reduce the level of tumor markers and improve the symptoms of OC patients. The combined detection of HE4, COX-1, and TVCDS has high sensitivity, specificity, and accuracy, which can effectively detect OC and reduce missed diagnosis and misdiagnosis.

The article describes a clinical case of cerebral venous thrombosis involving the deep venous system in a 42-year-old patient suffering from acute lymphoblastic leukemia. As the patient’s condition progressively deteriorated despite anticoagulant therapy, endovascular treatment was attempted. Transvenous thrombectomy and local thrombolysis were performed, which made it possible to achieve only partial recanalization. Further prolonged administration of alteplase into the cerebral sinus through a microcatheter facilitated complete recanalization of the direct and transverse sinuses. The restoration of blood flow was accompanied by regression of neurological deficit. This case is discussed in the context of modern approaches to endovascular treatment of cerebral venous thrombosis.

The diagnostic significance of the color Doppler study of testicular blood flow in testicular torsion has been studied for about 40 years, however, the prognostic value of the results obtained is ambiguous, as are the actual imaging capabilities of the technique. Our own experience of 110 observations of testicular torsion in children older than the neonatal period allows us to draw statistically reliable conclusions. Made on equipment premium-class research made it possible to evaluate how visualization intratesticular vascular pattern, and whirpool-sign and submit the primitive model of the actual inversion, explaining the impossibility of rendering whirpool-sign with the greatest tight inversion. The dynamics of testicular blood flow was studied immediately after successful and unsuccessful manual detorsion and in the long term after operative detorsion and orchopexy. The publication contains a brief analysis of the literature and is extensively illustrated.

The precise matching of blood flow to skeletal muscle during exercise remains an important area of investigation. Release of adenosine triphosphate (ATP) from red blood cells (RBCs) is postulated as a mediator of peripheral vascular tone in response to shear stress, hypoxia, and mechanical deformation. We tested the following hypotheses: 1) RBCs of different densities contain different quantities of ATP; 2) hypoxia is a stimulus for ATP release from RBCs; and 3) hypoxic ATP release from RBCs is related to RBC lysis. Human blood was drawn from male and female volunteers ( n = 11); the RBCs were isolated and washed. A Percoll gradient was used to separate RBCs based on cellular density. Density groups were then resuspended to 4% hematocrit and exposed to normoxia or hypoxia in a tonometer. Equilibrated samples were drawn and centrifuged; paired analyses of ATP (luminescence via a luciferase-catalyzed reaction) and hemolysis (Harboe spectrophotometric absorbance assay) were measured in the supernatant. ATP release was not different among low-density cells versus middle-density versus high-density cells. Similarly, hemoglobin (Hb) release was not different among the red blood cell subsets. No difference was found for either ATP release or Hb release following matched exposure to normoxic or hypoxic gas. The concentrations of ATP and Hb for all subsets combined were linearly correlated ( r = 0.59, P ≤ 0.001). With simultaneous probing for Hb and ATP in the supernatant of each sample, we conclude that ATP release from RBCs can be explained by hemolysis and that hypoxia per se does not stimulate either ATP release or Hb release from RBCs.

Since constant perfusion of blood throughout the brain is critical for neuronal health, the regulation of cerebral blood flow is complex and highly controlled. This regulation is controlled, in part, by the cerebral endothelium. In this review, multiple modes of endothelium-derived blood flow regulation is discussed, including chemical control of vascular tone, heterotypic and homotypic cell-cell interactions, second messenger signaling, and cellular response to physical forces and inflammatory mediators. Because cerebral small vessel disease is often associated with endothelial dysfunction and a compromised blood-brain barrier, understanding the endothelial factors that regulate vessel function to maintain cerebral blood flow and prevent vascular permeability may provide insights into disease prevention and treatment.