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1.
Adv Physiol Educ ; 44(2): 262-267, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32412381

ABSTRACT

Ultrasound imaging is being used increasingly to aid in the teaching of human physiology and anatomy. Here we describe how its use can be integrated into the teaching of concepts surrounding venous circulation, specifically 1) venous valves and the muscle pump, 2) the effects of hydrostatic pressure on venous pressure, and 3) central venous pressure. The imaging procedures described are relatively simple but add a dimension that helps deliver the teaching points clearly and is enjoyable for students. They also aid in the link of basic physiology to clinical aspects of venous circulatory physiology.


Subject(s)
Blood Pressure Determination , Models, Cardiovascular , Muscle, Skeletal/blood supply , Physiology/education , Students , Ultrasonography , Venous Pressure , Venous Valves/diagnostic imaging , Comprehension , Educational Measurement , Educational Status , Humans , Hydrostatic Pressure , Muscle Contraction , Venous Valves/physiology
2.
J Cardiovasc Electrophysiol ; 30(8): 1325-1329, 2019 08.
Article in English | MEDLINE | ID: mdl-31187551

ABSTRACT

INTRODUCTION: To deliver accurate morphological descriptions of the Vieussens valve (VV) and to investigate whether this structure could be visualized using standard contrast-enhanced electrocardiogram-gated multislice computed tomography (MSCT). METHODS: A total of 145 human autopsied hearts and 114 cardiac MSCT scans were examined. RESULTS: The VV was observed in both study groups, however, the detection rate was significantly worse in the MSCT examination (18.4% in MSCT vs 62.1% in cadavers, P < .0001). The VV height was larger in MSCT patients (2.8 ± 1.2 vs 5.4 ± 1.7 mm; P < .0001). No significant difference was found in the measured distance between the VV and the coronary sinus ostium between the two separate subgroups (27.3 ± 9.5 vs 24.4 ± 5.8 mm; P = .18). In autopsied material the most frequent valve location was the anterior wall of the coronary sinus (43.3%); the same was observed in MSCT scans (71.4%). CONCLUSION: The VV is a common heart structure, present in over 60% of humans, located mainly on the anterior and superior circuit of the coronary sinus, with relatively high morphological variability. Large VVs, which pose a significant obstacle in catheterization procedures, may be visualized using standard-protocol contrast-enhanced cardiac MSCT.


Subject(s)
Coronary Vessels/anatomy & histology , Coronary Vessels/diagnostic imaging , Multidetector Computed Tomography , Venous Valves/anatomy & histology , Venous Valves/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Autopsy , Cadaver , Cardiac-Gated Imaging Techniques , Electrocardiography , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Young Adult
3.
Cephalalgia ; 38(3): 600-603, 2018 03.
Article in English | MEDLINE | ID: mdl-28376658

ABSTRACT

Background Primary cough headache (PCH) is precipitated by coughing or the Valsalva manoeuver (VM), and its underlying pathophysiology remains unclear. Case report We report a case of recurrent cough headaches precipitated by VM with transient increase of intracranial pressure (ICP) diagnosed by measuring left sigmoid sinus pressure. Bilateral internal jugular vein valve incompetence (IJVVI) was also diagnosed by Doppler ultrasonography during a VM. Indomethacin was administered for over four months, and the headache had completely disappeared at the four-month follow-up. Conclusions Cough headache might be associated with a transient increase of ICP induced by IJVVI, which might partially explain the pathophysiology of VM-induced headache. Detecting the internal jugular vein during a VM might be used as diagnostic procedure for patients who have PCH during resting and VM. If it is necessary, monitoring the ICP could be considered.


Subject(s)
Headache Disorders, Primary/etiology , Intracranial Hypertension/complications , Jugular Veins/pathology , Venous Valves/pathology , Adult , Humans , Jugular Veins/diagnostic imaging , Male , Ultrasonography, Doppler, Color , Valsalva Maneuver , Venous Valves/diagnostic imaging
4.
Angiol Sosud Khir ; 24(1): 115-120, 2018.
Article in Russian | MEDLINE | ID: mdl-29688203

ABSTRACT

The purpose of the study was to examine a possibility of functional assessment of the great saphenous vein (GSV) with the help of a day orthostatic loading test for prognosis of restoration of the function of the GSV afterremoving its varicose tributaries in patients with primary varicose veins. Our prospective study included a total of sixty-five 29-to-53-year-old patients (15 men and 50 women, mean age - 36.7 years). The total number of the lower limb examined amounted to 87. All patients underwent ultrasonographic examination (duplex scanning) prior to operation, 1 and 12 months thereafter. The study was carried out using a day orthostatic loading test consisting in duplex scanning performed twice during 24 hours: in the evening after 18:00 hours and in the morning before 10:00 hours after a good night's rest. It was demonstrated that the day orthostatic loading test characterized the degree of preservation of the muscular-tonic properties of the GSV, making it possible to predict reversibility of reflux along it after removing the varicose tributaries, hence it may be used as a criterion for individualization of the choice of the scope of surgical intervention. A high orthostatic gradient prior to operation suggests preservation of the potential of the muscular-tonic function of the GSV; its decrease after surgery demonstrates reduction of the volemic loading on the GSV.


Subject(s)
Lower Extremity , Saphenous Vein , Ultrasonography, Doppler, Color/methods , Varicose Veins , Venous Insufficiency , Venous Valves , Adult , Female , Hemodynamic Monitoring/methods , Humans , Lower Extremity/blood supply , Lower Extremity/physiopathology , Male , Posture/physiology , Predictive Value of Tests , Prognosis , Regional Blood Flow , Reproducibility of Results , Saphenous Vein/diagnostic imaging , Saphenous Vein/physiopathology , Varicose Veins/diagnosis , Varicose Veins/physiopathology , Venous Insufficiency/diagnosis , Venous Insufficiency/physiopathology , Venous Valves/diagnostic imaging , Venous Valves/physiopathology
6.
Angiol Sosud Khir ; 23(4): 35-42, 2017.
Article in Russian | MEDLINE | ID: mdl-29240053

ABSTRACT

AIM: The purpose of the study was to work out a method of preventive diagnosis of venous thromboses by means of ultrasonographic duplex scanning (USDS). PATIENTS AND METHODS: A total of 306 people were examined. Of these, 146 patients presented with acute venous thrombosis, 108 subjects suffered from varicose veins, and 52 were apparently healthy people composing the control group. All those enrolled into the study were examined by means of USDS, with the D-dimer level determined. RESULTS: The obtained findings made it possible to discover and duly describe an ultrasonographic phenomenon of the presence of echo-positive inclusions in the zone of valvular sinuses, which was called the phenomenon of spontaneous echo contrast (SEC). This was followed by working out a classification of this phenomenon, describing two degrees thereof. Degree 1 SEC reflects the fact that the area of valvular sinuses is the most thrombogenic zone. Degree 2 SEC is characterised as a pathological, being simultaneously pre-thrombotic, condition and may serve as one of the earliest predictors of the development of venous thrombosis. A close correlation was established between the degree 2 SEC phenomenon, the presence of venous thrombosis and the values of the D-dimer level (r=0.89, p<0.01). CONCLUSION: Ultrasonographic examination of valvular sinuses is a simple, readily available and reproducible method of screening and may thus be used for preventive diagnosis of acute venous thromboses. The findings of this study make it possible to form risk groups by the development of deep vein thrombosis, as well as to initiate timely measures on prevention of the pathology concerned.


Subject(s)
Fibrin Fibrinogen Degradation Products/analysis , Ultrasonography, Doppler, Duplex/methods , Venous Thrombosis , Venous Valves/diagnostic imaging , Acute Disease , Adult , Female , Humans , Male , Mass Screening/methods , Middle Aged , Predictive Value of Tests , Prognosis , Varicose Veins/complications , Venous Thrombosis/diagnosis , Venous Thrombosis/etiology
7.
Khirurgiia (Mosk) ; (5): 14-18, 2015.
Article in Russian | MEDLINE | ID: mdl-26271317

ABSTRACT

MATERIAL AND METHODS: It was analyzed the results of complex survey and treatment of 181 patients with varicose disease CEAP degrees C3-C6. Ultrasonic scanning was applied to define localization, severity and extension of blood reflux in venous system. RESULTS: Superficial reflux was revealed in all patients, perforating--in 59.7%, deep--in 22.8% of cases. We concluded that high-intensive total-subtotal blood reflux in superficial veins was main hemodynamic factor resulted perforating insufficiency in 42% of patients, high-intensive deep reflux--in 17.7% of cases additionally. In patients with subcompensated course of disease superficial reflux removal and large perforating veins (diameter 4.5±0.5 mm) ligation are advisable. Small perforating veins insufficiency (diameter 3.5±0.5 mm) is eliminated independently after superficial reflux removal. Two-staged treatment should be used in patients with decompensated course of disease and trophic disorders ofshin. Perforating veins sclerotherapy under ultrasonic control is advisable secondarily after superficial reflux removal.


Subject(s)
Lower Extremity/blood supply , Postoperative Complications , Sclerotherapy/methods , Varicose Veins , Vascular Surgical Procedures , Venous Insufficiency , Venous Valves , Adult , Aged , Female , Hemodynamics , Humans , Ligation/adverse effects , Ligation/methods , Male , Middle Aged , Outcome Assessment, Health Care , Postoperative Complications/diagnosis , Postoperative Complications/physiopathology , Postoperative Complications/prevention & control , Ultrasonography , Varicose Ulcer/etiology , Varicose Ulcer/prevention & control , Varicose Veins/complications , Varicose Veins/diagnosis , Varicose Veins/physiopathology , Varicose Veins/surgery , Vascular Surgical Procedures/adverse effects , Vascular Surgical Procedures/methods , Venous Insufficiency/diagnosis , Venous Insufficiency/etiology , Venous Insufficiency/physiopathology , Venous Insufficiency/prevention & control , Venous Valves/diagnostic imaging , Venous Valves/physiopathology , Venous Valves/surgery
8.
J Vasc Interv Radiol ; 25(1): 144-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24365509

ABSTRACT

Transposition of a deep (9-12 mm) autogenous brachiocephalic vein fistula was required for adequate hemodialysis access in a morbidly obese patient. The patient was a poor candidate for surgical transposition of the upper-arm cephalic vein. As an alternative, retrograde fistula flow was established percutaneously through a 6-F sheath in the forearm cephalic vein with the over-the-wire LeMaitre valvulotome. The retrograde flow in the forearm added 7 cm of superficial vein 6.2-9 mm in diameter with a flow rate of 940-2,868 mL/min, eliminating the need for surgical transposition. The percutaneous technique and required anatomy are described.


Subject(s)
Arteriovenous Shunt, Surgical/methods , Brachial Artery/surgery , Endovascular Procedures , Forearm/blood supply , Renal Dialysis , Venous Valves/physiopathology , Arteriovenous Shunt, Surgical/adverse effects , Blood Flow Velocity , Brachial Artery/physiopathology , Embolization, Therapeutic , Humans , Male , Middle Aged , Phlebography , Regional Blood Flow , Treatment Outcome , Ultrasonography, Doppler, Duplex , Venous Valves/diagnostic imaging
9.
J Ultrasound Med ; 33(5): 803-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24764335

ABSTRACT

OBJECTIVES: The purpose of this study was to determine the changes (if any) in the diameter and valve closure time of the lower limb veins in healthy young nulliparous women at different phases of the menstrual cycle. METHODS: Fifty-three young nulliparous women were asked to undergo clinical evaluations and duplex ultrasound examinations of both lower limb veins to monitor changes in the vein diameter and valve closure time at different phases of their menstrual cycles. The vein diameter on B-mode imaging and valve closure time on pulsed Doppler tracing were calculated at days 1 to 4, 14 to 16, and 25 to 28 of the menstrual cycle. Freidman and related samples Wilcoxon signed rank tests were used to determine time-related changes in venous function. RESULTS: The volunteers' mean age ± SD was 20.60 ± 1.90 years, and their mean body mass index was 23.90 ± 4.90 kg/m(2). There was a gradual increase in the vein diameter and valve closure time at the specified phases of the menstrual cycle. Friedman and related samples Wilcoxon signed rank tests for venous segment diameter and valve closure time changes between the different phases of the menstrual cycle were performed and showed statistical significance for each venous segment within each limb (P = .003-.025). Also, when adjusted for body mass index, statistical significance existed for the same venous segments in the same limbs (P =.001-.049). There was no statistical significance for the same venous segments at the same phase of the menstrual cycle between limbs (related samples Wilcoxon signed rank test: P =.079-.97). CONCLUSIONS: During the menstrual cycle, the lower limb veins show an increase in their diameter and valve closure time. These changes are probably mediated by the female sex hormones.


Subject(s)
Leg/blood supply , Leg/physiology , Menstrual Cycle/physiology , Ultrasonography, Doppler, Duplex/methods , Vascular Resistance/physiology , Venous Valves/diagnostic imaging , Venous Valves/physiology , Female , Humans , Leg/diagnostic imaging , Reproducibility of Results , Sensitivity and Specificity , Young Adult
10.
Rozhl Chir ; 93(2): 57-62, 2014 Feb.
Article in Cs | MEDLINE | ID: mdl-24702288

ABSTRACT

Endovenous ablation of varicose veins is a very frequent treatment method which has more or less replaced the classic stripping method. It has its limitations, advantages as well as disadvantages. The authors present a summarizing article and their own experience with these methods. Histology examinations performed prove differences in the reaction of the endothelium to the individual types of endovenous therapy. Causes of varicose veins treatment failures are discussed.


Subject(s)
Catheter Ablation/methods , Catheter Ablation/trends , Saphenous Vein/surgery , Varicose Veins/surgery , Venous Valves/pathology , Adolescent , Adult , Aged , Endothelium, Vascular/pathology , Endothelium, Vascular/surgery , Female , Humans , Male , Middle Aged , Outcome and Process Assessment, Health Care , Radiography , Saphenous Vein/pathology , Varicose Veins/pathology , Venous Valves/diagnostic imaging , Young Adult
11.
J Headache Pain ; 14: 78, 2013 Sep 23.
Article in English | MEDLINE | ID: mdl-24059639

ABSTRACT

BACKGROUND: Migraine is a common neurological disorder of unclear pathogenesis. Recently incompetence of internal jugular vein valve (IJVVI) was found to be associated with some neurological conditions of unknown etiology such as benign cough headache, primary exertional headache or transient global amnesia. Common vascular mechanism linking transiently increased cerebral venous pressure with the above mentioned conditions was then postulated. Therefore we decided to investigate whether IJVVI may be associated with migraine. AIM AND METHODS: The aim of our study was to evaluate the occurrence of IJVVI and retrograde flow duration in 70 (56 females) migraine patients by color Doppler ultrasound during Valsalva maneuver.We assessed internal jugular vein valve in 44 patients with migraine without aura (39 female); mean age 37 ± 9 yrs. and in 26 patients with migraine with typical aura (17 female); mean age 34 ± 9 yrs. Age- and sex-matched control group consisted of 42 healthy persons (33 female); mean age 32 ± 1 yrs. RESULTS: Frequency of the internal jugular vein valve insufficiency was similar in patients with migraine and in the healthy subjects (51% v. 40%, p = 0.26). Also mean values of retrograde flow duration were similar in both groups (2.4 ± 0.8 sec in migraine group and 2.2 ± 1.2 sec in controls, p = 0.14). CONCLUSION: The results of our study show no evidence for an increased prevalence of IJVVI in migraine patients.


Subject(s)
Cerebrovascular Disorders/diagnostic imaging , Jugular Veins/diagnostic imaging , Migraine Disorders/diagnostic imaging , Venous Valves/diagnostic imaging , Adult , Cerebrovascular Disorders/complications , Female , Humans , Male , Migraine Disorders/complications , Ultrasonography
12.
Vasc Endovascular Surg ; 57(6): 547-554, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36745015

ABSTRACT

OBJECTIVE: Two-year follow-up results from a first-in-human study of patients implanted with the VenoValve are evaluated for supporting the long-term clinical safety and performance of the device. BACKGROUND: Chronic Venous Insufficiency (CVI) involves improper functioning of lower limb vein valves and inability of these valves to move blood back towards the heart. CVI symptoms include swelling, varicose veins, pain, and leg ulcers. Currently, there is no cure for this condition and treatment options are limited. This study provides 2-year outcomes for 8 patients who were implanted with the bioprosthetic VenoValve for treating severe CVI with deep venous reflux measured at the mid-popliteal vein. The 6-month and 1-year results were previously published. METHODS: Eleven patients with C5 & C6 CVI were implanted with VenoValve into the midthigh femoral vein and followed for 2 years. Assessed clinical outcomes include device-related adverse events, reflux time, disease severity, and pain scores. RESULTS: All 11 implant procedures were successful. Two-year follow-up data was obtained for 8 subjects: 1 patient died of non-device related causes, 1 was lost to follow-up, and 1 refused to follow-up due to the COVID-19 pandemic. No device-related adverse events occurred between the first and second years of follow-up. Reported 2-year clinical performance outcomes included significant decreases in mean reflux times of the mid-popliteal vein (61%), and significant improvements in mean scores for disease severity rVCSS (56%) and VAS pain (87%). CONCLUSIONS: Results from this study support long-term safety and effectiveness of the VenoValve for improving CVI severity by reducing reflux and thereby venous pressures in the lower extremities. With limited treatments for valvular incompetence involved in severe, deep venous CVI, the device may be considered as a novel therapy. A pivotal trial in the United States is currently being conducted to assess the device in a larger number of patients.


Subject(s)
COVID-19 , Venous Insufficiency , Venous Valves , Humans , Venous Valves/diagnostic imaging , Venous Valves/surgery , Pandemics , Treatment Outcome , Venous Insufficiency/diagnostic imaging , Venous Insufficiency/etiology , Venous Insufficiency/surgery , Femoral Vein/diagnostic imaging , Femoral Vein/surgery , Pain , Chronic Disease
13.
Eur J Vasc Endovasc Surg ; 44(3): 337-40, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22824347

ABSTRACT

PURPOSE: The aim of the study is to investigate the relative position of orifices of two valves within the most proximal segments of the great saphenous vein (GSV), and the femoral vein (FV). METHODS: A total of 15 volunteers with no signs or symptoms of venous disease and 13 unaffected limbs of patients with unilateral primary chronic venous disease (CVD) were included. Two most proximal valves of the GSV and the FV were identified. The angle between the two valves, and the distance between the valves were measured. RESULTS: The mean distance between the two valves in the GSV was 3.8 ± 0.4 cm, and in the FV was 4.6 ± 0.3 cm. In one limb, the distance between the FV valves was 1 cm less than GSV valves, and in two limbs the distances were equal. In the remaining 12 limbs available for comparison, the valves in the FV were 1-2 cm further apart compared to the GSV (P = 0.002, paired t-test). All studied pairs of valves were positioned at a minimum 60° angle to each other. The mean angle between the two valves was 84.3 ± 8.4° in the GSV, and 88.3 ± 6.7° in the FV (P = 0.24). The angle between the two valves correlated with the distance between the valves (r = 0.68, P = 0.000005). No significant relations were found between the diameter of the studied vein, and the angle between the two valves. There was no difference in valve orientation between volunteers and unaffected limbs of the patients with CVD. CONCLUSION: When two valves are present in the areas of venous junctions, they consistently positioned at a significant angle to each other. A hypothesis that venous valves at the junctions increase efficiency of venous return by creating a helical flow pattern can be postulated and deserves further investigation.


Subject(s)
Femoral Vein/diagnostic imaging , Hemodynamics , Saphenous Vein/diagnostic imaging , Ultrasonography, Doppler, Duplex , Venous Insufficiency/diagnostic imaging , Venous Valves/diagnostic imaging , Blood Flow Velocity , Case-Control Studies , Chronic Disease , Femoral Vein/physiopathology , Hawaii , Humans , Regional Blood Flow , Saphenous Vein/physiopathology , Venous Insufficiency/physiopathology , Venous Valves/physiopathology
14.
Arterioscler Thromb Vasc Biol ; 30(10): 2075-80, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20671232

ABSTRACT

OBJECTIVE: Age is the strongest risk factor for venous thrombosis. Vessel wall changes such as thickening of venous valves may be one of the contributing mechanisms. We determined thickness and function of venous valves in the popliteal vein with ultrasound in 77 healthy individuals. METHODS AND RESULTS: The study included 6 age groups ranging from 20 to 80 years old. Thickness of the valves was compared between age groups. Valve closure time was assessed as an indicator for valve function. In 69 of 77 participants, valve parameters could be measured. We found an increasing thickness of the valves with age, with a mean thickness of 0.35 mm (range, 0.25 to 0.44 mm) in the group of 20 to 30 years and 0.59 mm (range, 0.30 to 1.21 mm) in the group of 71 to 80 years. The increase in valve thickness per year (linear regression coefficient) was 0.004 mm (95% CI, 0 to 0.009). Valve function was not directly associated with age. Valve thickness, however, was inversely associated with valve function. CONCLUSIONS: Our results show that deep venous valves change with age, with thicker valves in older individuals. The increase of valve thickness with age may be part of the explanation for the age gradient seen in the incidence of venous thrombosis.


Subject(s)
Aging/pathology , Venous Valves/pathology , Adult , Aged , Aging/physiology , Female , Humans , Male , Middle Aged , Risk Factors , Ultrasonography , Venous Thrombosis/diagnostic imaging , Venous Thrombosis/pathology , Venous Thrombosis/physiopathology , Venous Valves/diagnostic imaging , Venous Valves/physiopathology , Young Adult
15.
Circ Cardiovasc Imaging ; 14(5): e010977, 2021 05.
Article in English | MEDLINE | ID: mdl-33993704

ABSTRACT

Anatomic variants in the right atrium are under-recognized and under-reported phenomena in cardiac imaging. In the fetus, right atrium serves as a conduit for oxygenated blood to be delivered to the left heart bypassing the right ventricle and the nonfunctional lungs. The anatomy in the fetal right atrium is designed for such purposeful circulation. The right and left venous valves are prominent structures in the fetal heart that direct inferior vena caval flow towards the foramen ovale. These anatomic structures typically regress and the foramen ovale closes after birth. However, the venous valves can persist leading to a range of anatomic, physiological, and pathological consequences in the adult. We describe various presentations of persistent venous valves, focusing on the right venous valve in this illustrated multimodality imaging article.


Subject(s)
Fetal Heart/diagnostic imaging , Heart Atria/diagnostic imaging , Prenatal Diagnosis/methods , Vena Cava, Inferior/diagnostic imaging , Venous Valves/diagnostic imaging , Echocardiography/methods , Female , Heart Atria/abnormalities , Humans , Pregnancy , Vena Cava, Inferior/abnormalities , Venous Valves/abnormalities
16.
Sci Rep ; 11(1): 11602, 2021 06 02.
Article in English | MEDLINE | ID: mdl-34078949

ABSTRACT

Saphenous veins (SVs) are frequently employed as bypass grafts. The SV graft failure is predominantly seen at the valve site. Avoiding valves during vein harvest would help reduce graft failure. We endeavored to detect SV valves, tributaries, and vessel size employing upright computed tomography (CT) for the raw cadaver venous samples and in healthy volunteers. Five cadaver legs were scanned. Anatomical analysis showed 3.0 (IQR: 2.0-3.0) valves and 13.50 (IQR: 10.00-16.25) tributaries. The upright CT completely detected, compared to 2.0 (IQR: 1.5-2.5, p = 0.06) valves and 9.5 (IQR: 7.5-13.0, p = 0.13) tributaries by supine CT. From a total of 190 volunteers, 138 (men:75, women:63) were included. The number of valves from the SF junction to 35 cm were significantly higher in upright CT than in supine CT bilaterally [upright vs. supine, Right: 4 (IQR: 3-5) vs. 2 (IQR:1-2), p < 0.0001, Left: 4 (IQR: 3-5) vs. 2 (IQR: 1-2), p < 0.0001]. The number of tributaries and vessel areas per leg were also higher for upright compared with supine CT. Upright CT enables non-invasive detection of SV valves, tributaries, and vessel size. Although not tested here, it is expected that upright CT may potentially improve graft assessment for bypass surgery.


Subject(s)
Saphenous Vein/diagnostic imaging , Standing Position , Tomography, X-Ray Computed/methods , Venous Valves/diagnostic imaging , Adult , Aged , Aged, 80 and over , Cadaver , Female , Healthy Volunteers , Humans , Leg/blood supply , Male , Middle Aged , Saphenous Vein/anatomy & histology , Supine Position , Vascular Grafting/methods , Venous Valves/anatomy & histology
17.
JCI Insight ; 6(18)2021 09 22.
Article in English | MEDLINE | ID: mdl-34403370

ABSTRACT

Venous valve (VV) failure causes chronic venous insufficiency, but the molecular regulation of valve development is poorly understood. A primary lymphatic anomaly, caused by mutations in the receptor tyrosine kinase EPHB4, was recently described, with these patients also presenting with venous insufficiency. Whether the venous anomalies are the result of an effect on VVs is not known. VV formation requires complex "organization" of valve-forming endothelial cells, including their reorientation perpendicular to the direction of blood flow. Using quantitative ultrasound, we identified substantial VV aplasia and deep venous reflux in patients with mutations in EPHB4. We used a GFP reporter in mice to study expression of its ligand, ephrinB2, and analyzed developmental phenotypes after conditional deletion of floxed Ephb4 and Efnb2 alleles. EphB4 and ephrinB2 expression patterns were dynamically regulated around organizing valve-forming cells. Efnb2 deletion disrupted the normal endothelial expression patterns of the gap junction proteins connexin37 and connexin43 (both required for normal valve development) around reorientating valve-forming cells and produced deficient valve-forming cell elongation, reorientation, polarity, and proliferation. Ephb4 was also required for valve-forming cell organization and subsequent growth of the valve leaflets. These results uncover a potentially novel cause of primary human VV aplasia.


Subject(s)
Ephrin-B2/genetics , Receptor, EphB4/genetics , Receptor, EphB4/metabolism , Venous Valves/abnormalities , Venous Valves/embryology , Animals , Aorta/ultrastructure , Cell Communication , Cell Polarity , Cell Proliferation , Connexin 43/metabolism , Connexins/metabolism , Endothelium , Ephrin-B2/metabolism , Humans , Mice , Mice, Knockout , Mutation , Phenotype , Ultrasonography , Vascular Malformations/diagnostic imaging , Vascular Malformations/genetics , Venous Insufficiency/diagnostic imaging , Venous Valves/diagnostic imaging , Gap Junction alpha-4 Protein
19.
Rom J Morphol Embryol ; 51(1): 157-61, 2010.
Article in English | MEDLINE | ID: mdl-20191137

ABSTRACT

The valvular segment is a distinct venous structure, which, from a morphological point of view, is comprised of the following components: the valvular insertion, the valvular gorge entrance orifice, the valvular defile, the valvular gorge exit orifice, the valvular sinus. Endoscopic and echo Doppler examinations are used to identify the normal and the pathological morphology of the valvular segment, and the hemodynamic phenomena occurring at this level. Cusps' integrity and size as well as valvular dynamics are key elements directly involved in shaping the valvular segment in general, and the valvular sinus in particular. The valvular sinus shows an obvious hemodynamic determinism. Valvular segment pathology is the outcome either of a progressively long evolving process initialized by gravitational venous pressure overcharges, or of a rapidly evolving process such as the hemodynamic shock following intense physical efforts. Valvular defunctionalisation implies a different mechanism and a different type of cusp lesion.


Subject(s)
Lower Extremity/blood supply , Venous Valves/anatomy & histology , Venous Valves/pathology , Venous Valves/physiology , Endosonography , Hemodynamics , Humans , Lower Extremity/diagnostic imaging , Peripheral Vascular Diseases/diagnostic imaging , Peripheral Vascular Diseases/pathology , Peripheral Vascular Diseases/physiopathology , Ultrasonography, Doppler, Duplex , Venous Insufficiency/diagnostic imaging , Venous Insufficiency/pathology , Venous Insufficiency/physiopathology , Venous Valves/diagnostic imaging
20.
Clin Hemorheol Microcirc ; 76(2): 211-219, 2020.
Article in English | MEDLINE | ID: mdl-32925009

ABSTRACT

PURPOSE: The aim of our pilot study is to consider if the new flow presentation of the vector flow (V-flow) allows an assessment of the valve morphology of the crosses with respect to an insufficiency. MATERIAL AND METHODS: We performed a total of 50 investigations in which we documented a complete valve closure at the so called "crosse" at the valve of the large saphenous vein, a delayed valve closure or an incomplete valve closure with consecutive insufficiency at the crosse. The valve function of the crosse is crucial for the development of varicosis. For our study we recorded age and gender of the patients. One patient in the study was suffering from Covid19. For the examinations we used a 3-9 MHz probe and a high-end ultrasound device. The examination was performed in a lying position and under quiet conditions. Before examination we practiced inhalation and exhalation as well as "pressing" or coughing with the patients, which resulted in a physiological closure of the venous valves. To rule out thrombosis, we carried out compression sonography on the legs. During the examination we documented the B-scan, the Color-Coded Duplex Sonography, the HR-flow and the V-flow for 3 seconds at the estuary of the crosses and incorporated these parameters into our measurements. Via V-flow, vectors can be imaged by representing the flow of erythrocytes and visually indicate a possible insufficiency due to delayed or incomplete valve closure. RESULTS: 31 of 50 patients (age 19-81years) showed a complete valve closure of the crosses, three of them suffered from thrombosis. In eight of the 50 study participants (age 45-79 years) a delayed valve closure could be diagnosed by V-flow within 1-2 seconds. None of them had a thrombosis, but six of them suffered from cancer. In eleven patients we derived an incomplete valve closure with insufficiency (age 51-88 years). With reflux it took >2 seconds to close the valve. The patient with Covid19 also showed an incomplete valve closure with insufficiency. At the same time this patient showed a Covid19-associated deep vein thrombosis. Eight additional patients also had a thrombosis. Six of them suffered from cancer. Overall, the results were best visualized by V-Flow. CONCLUSION: The crosse as a significant venous structure can be well investigated by V-flow with respect to hemodynamic changes and a resulted reflux. Also associated changes close to the valve can be visualized well.


Subject(s)
Saphenous Vein/diagnostic imaging , Venous Valves/diagnostic imaging , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Pilot Projects , Venous Insufficiency/physiopathology , Young Adult
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