Internal jugular vein valve incompetence in COPD and primary pulmonary hypertension

Cerebral venous congestion exacerbates cerebral microhemorrhages in mice

Cerebral microhemorrhages (CMHs; microbleeds), which are small focal intracerebral hemorrhages, importantly contribute to the pathogenesis of cognitive decline and dementia in older adults. Although recently it has been increasingly recognized that the venous side of the cerebral circulation likely plays a fundamental role in the pathogenesis of a wide spectrum of cerebrovascular and brain disorders, its role in the pathogenesis of CMHs has never been studied. The present study was designed to experimentally test the hypothesis that venous congestion can exacerbate the genesis of CMHs. Increased cerebral venous pressure was induced by internal and external jugular vein ligation (JVL) in C57BL/6 mice in which systemic hypertension was induced by treatment with angiotensin II plus L-NAME. Histological analysis (diaminobenzidine staining) showed that mice with JVL developed multiple CMHs. CMHs in mice with JVL were often localized adjacent to veins and venules and their morphology was consistent with venous origin of the bleeds. In brains of mice with JVL, a higher total count of CMHs was observed compared to control mice. CMHs were distributed widely in the brain of mice with JVL, including the cortical gray matter, brain stem, the basal ganglia, subcortical white matter, cerebellum, and the hippocampi. In mice with JVL, there were more CMHs predominantly in cerebral cortex, brain stem, and cerebellum than in control mice. CMH burden, defined as total CMH volume, also significantly increased in mice with JVL. Thus, cerebral venous congestion can exacerbate CMHs. These observations have relevance to the pathogenesis of cognitive impairment associated with right heart failure as well as elevated cerebral venous pressure due to jugular venous reflux in older adults.

Association between lower extremity venous insufficiency and duration of atrial fibrillation

OBJECTIVE

Physiologic studies have shown that atrium has an active role in venous blood return from lower extremity. In this context we investigated the association between AF and chronic venous disease (CVD).

METHODS

In this observational study we included 392 AF patients which were divided into two groups (chronic AF, 218 (56%)) and non-chronic. AF, 174 (44%)). These two groups were compared in terms of CVD after matching conventional risk factors for CVD.

RESULTS

CEAP classification was different between chronic and non-chronic patients (C0-C2: 72% vs 47%; C3-C6: 28% vs 53% <0.001). Chronic AF patients had also higher rate of venous reflux on Doppler ultrasound (38% vs 16% P < 0.05). There was a correlation between AF duration, right atrial volume index and CEAP classification respectively (rho:0.314 p < 0.001), (rho:0.258, p < 0.001).

CONCLUSION

Prevalence of CVD is higher in patients with chronic AF. In addition, atrial volume is directly correlated with CVD.

Heritability of the dimensions, compliance and distensibility of the human internal jugular vein wall

Aims

The elasticity of the internal jugular vein (IJV) is a major determinant of cerebral venous drainage and right atrium venous return. However, the level of genetic determination of IJV dimensions, compliance and distensibility has not been studied yet.

Methods

170 adult Caucasian twins (43 monozygotic [MZ] and 42 dizygotic [DZ] pairs) were involved from the Italian twin registry. Anteroposterior and mediolateral diameters of the IJV were measured bilaterally by ultrasonography. Measurements were made both in the sitting and supine positions, with or without Valsalva maneuver. Univariate quantitative genetic modeling was performed.

Results

Genetic factors are responsible for 30–70% of the measured properties of IJV at higher venous pressure even after adjustment for age and gender. The highest level of inheritance was found in the supine position regarding compliance (62%) and venous diameter during Valsalva (69%). Environmental and measurement-related factors instead are more important in the sitting position, when the venous pressure is low and the venous lumen is almost collapsed. The range of capacity changes between the lowest and highest intraluminal venous pressure (full distension range) are mainly determined by genetic factors (58%).

Conclusions

Our study has shown substantial heritability of IJV biomechanics at higher venous pressures even after adjustment for age and gender. These findings yield an important insight to what degree the geometric and elastic properties of the vascular wall are formed by genetic and by environmental factors in humans.

Primary pulmonary arterial hypertension with preserved right ventricular function leads to lower extremity venous insufficiency

Objectives

Pulmonary hypertension with heart failure is related to venous insufficiency. However, there is no clear data whether pulmonary arterial hypertension with preserved right ventricular function cause venous insufficiency. In this study, we aim to investigate the relation between pulmonary arterial pressure with venous insufficiency in pulmonary arterial hypertension patients with preserved right ventricular function.

Methods

Between January 2012 and October 2014, 38 patients with a diagnosis of pulmonary arterial hypertension and 47 control group patients were included. Venous disability score and venous segmental disease score of both groups were calculated in order to measure venous insufficiency. The relationship between venous disability score and venous segmental disease scores and mean pulmonary arterial pressure and World Heart Organization functional capacity was examined.

Results

Total venous segmental disease score (5 ± 3.9 vs. 2 ± 1.8 p < 0.001), right venous segmental disease score (2.6 ± 2.2 vs. 1 ± 0.9 p < 0.001), left venous segmental disease score (2.4 ± 2.2 vs. 1 ± 0.9 p < 0.001), and venous disability scores (2.2 ±1 vs. 1.6 ± 0.7 p < 0.001) of patients with pulmonary arterial hypertension were higher than the control group. While the total venous segmental disease score was highly related to mean pulmonary arterial pressure (r = 0.829, p < 0.001), the venous disability score was only weakly related (r = 0.343, p = 0.037). Total venous segmental disease score (r = 0.606, p < 0.001) and venous disability scores (r = 0.601, p < 0.001) were moderately related with World Health Organization functional capacity intensity.

Conclusions

The degree of venous insufficiency increase in accordance with the mean pulmonary arterial pressure even in patients with preserved right ventricular function.

Multiple Sclerosis - A Vascular Etiology?

From the earliest pathological studies the perivenular localization of the demyelination in multiple sclerosis (MS) has been observed. It has recently been suggested that obstructions to venous flow or inadequate venous valves in the great veins in the neck, thorax and abdomen can cause damaging backflow into the cerebral and spinal cord circulations. Paolo Zamboni and colleagues have demonstrated abnormal venous circulation in some multiple sclerosis patients using non-invasive sonography and invasive venography. Furthermore, they have obtained apparent clinical improvement or stabilization by endovascular ballooning of points of obstruction in the great veins in some, at least temporarily. If non-invasive observations by others validate their initial observations of a significantly increased prevalence of venous obstructions in MS then trials of angioplasty/stenting would be justified in selected cases in view of the biological plausibility of the concept.

Original Research: Feasibility and safety of two surgical techniques for the development of an animal model of jugular vein occlusion

To date, no studies have explored the effect of abnormal cerebral venous circulation on brain disorders, whereas many studies have investigated neurodegenerative brain anomalies associated with arterial diseases. The aim of our study was to demonstrate the feasibility of different surgical techniques to induce venous obstruction of cerebral brain drainage. Six C57/black mice underwent bilateral occlusion of the external jugular vein (group EJV), six underwent bilateral occlusion of the internal jugular vein (group IJV), and six underwent bilateral occlusion of both the EJV and the IJV (group EJV/IJV). Within each group, the interruption of blood flow was obtained via monopolar electro-coagulation (ME) in three mice and via surgical ligation (SL) in the remaining three mice. A "sham group" of two mice was used as the control. High-frequency ultrasound (HFUS) was used to detect the absence of blood flow in the examined vessel. The ME procedure led to successful results in two of nine (22%) mice, one in the EJV group, one in the EJV/IJV group, and zero in the IJV group, and 4 of 18 (22%) mice when considering individual veins (i.e., total number of EJVs and IJVs occluded). The SL procedure was successful in two of three (67%) mice in the EJV group, in three of three (100%) mice in the IJV and in three of four (75%) mice in the EJV/IJV group. Therefore, the overall success rate was 8/10 (80%) when considering mice, and 20/26 (77%) when considering individual veins. The monopolar electro-coagulation method exhibited a high mortality due to cardiorespiratory arrest, while the results of the bilateral surgical ligation of EJVs and IJVs show that it is technically feasible and safe.

Medical Tourism for CCSVI Procedures in People with Multiple Sclerosis: An Observational Study

BACKGROUND

Many Canadians with multiple sclerosis (MS) have recently travelled internationally to have procedures for a putative condition called chronic cerebrospinal venous insufficiency (CCSVI). Here, we describe where and when they went and describe the baseline characteristics of persons with MS who participated in this non-evidence-based medical tourism for CCSVI procedures.

METHODS

We conducted a longitudinal observational study that used online questionnaires to collect patient-reported information about the safety, experiences, and outcomes following procedures for CCSVI. A convenience sample of all Albertans with MS was recruited between July 2011 and March 2013.

RESULTS

In total, 868 individuals enrolled; 704 were included in this cross-sectional, baseline analysis. Of these, 128 (18.2%) participants retrospectively reported having procedures for CCSVI between April 2010 and September 2012. The proportion of participants reporting CCSVI procedures declined from 80 (62.5%) in 2010, to 40 (31.1%) in 2011, and 8 (6.3%) in 2012. In multivariable logistic regression analysis, CCSVI procedures were independently associated with longer disease duration, secondary progressive clinical course, and greater disability status.

CONCLUSIONS

Although all types of people with MS pursued procedures for CCSVI, a major driver of participation was greater disability. This highlights that those with the greatest disability are the most vulnerable to unproven experimental procedures. Participation in CCSVI procedures waned over time possibly reflecting unmet expectations of treated patients, decreased media attention, or that individuals who wanted procedures had them soon after the CCSVI hypothesis was widely publicized.

Ultrasound evaluation of internal jugular valve incompetence (IJVI) in Egyptian patients with idiopathic intracranial hypertension (IIH)

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a clinical syndrome with no identified causative factor. Internal jugular valve incompetence (IJVI) has been linked to many neurological disorders such as idiopathic intracranial hypertension (IIH), transient global amnesia and cough-induced headache. Intact valves prevent efficiently retrograde flow into the internal jugular vein.

AIM

The aim of this study is to evaluate the competence of the jugular vein valves and its relationship to age, BMI, opening CSF pressure and MRV findings in IIH patients.

SUBJECTS AND METHODS

Twenty-five Egyptian female patients diagnosed with IIH according to the modified Dandy criteria, and 24 female controls, matched for age and BMI, were included and examined using color-coded duplex for IJVI during the Valsalva maneuver. The patients underwent lumbar puncture to measure the opening pressure, MRV, ophthalmic examination and laboratory work-up.

RESULTS

There was no statistically significant difference in the proportion of IJVI among the patients and controls (P=0.7). There was a statistically significant increase in the opening pressure and proportion of MRV abnormalities in the patients with IJVI compared to the patients without IJVI (P=0.03 and 0.007, respectively), but there were no statistically significant difference with regard to age, BMI, grade of papilledema and perimetry findings.

CONCLUSION

This study showed that there is no relationship between IJVI and IIH; thus, IJVI would be a rather normal finding. Further studies are recommended to confirm or rule out a possible relationship.

Internal jugular vein blood flow in multiple sclerosis patients and matched controls

The aim of the study was to investigate the Internal Jugular Veins dynamics using contrast enhanced ultrasonography in Multiple Sclerosis patients, clinically isolated syndrome patients and healthy controls. Contrast enhanced ultrasonography imaging of the Internal Jugular Vein was performed in fifty-eight patients with Multiple Sclerosis, seven clinically isolated syndrome patients and in thirteen healthy controls. Time-intensity curves were quantified using a semi-automated method and compared with clinical disease outcomes. Wash-out parameters were calculated and six Time-intensity curves shapes were created. Significantly reduction of wash-out rate in Internal Jugular Veins was detected in Multiple Sclerosis patients compared to healthy controls [22.2% (2.7%–65.9%) vs. 33.4% (16.2%–76.8%); P<0.005]. Internal Jugular Vein enhancement was heterogeneous in patients with Multiple Sclerosis and consisted of slow wash-out Time-intensity curves shapes, compared with almost only one type of Time-intensity curves shape in control subjects that correspond to fast enhancement and fast wash-out. The vein wash-in parameters were similar in Multiple Sclerosis group compared with controls. A significant correlation was found between Internal Jugular Vein wash-out and level of disability (R = −0.402, p<0.05). Contrast enhanced ultrasonography of the Internal Jugular Vein with time intensity curve analysis revealed alterations of cerebral venous outflow in Multiple Sclerosis patients, however mechanisms that determine this condition remains unclear.

Potential involvement of the extracranial venous system in central nervous system disorders and aging

BACKGROUND

The role of the extracranial venous system in the pathology of central nervous system (CNS) disorders and aging is largely unknown. It is acknowledged that the development of the venous system is subject to many variations and that these variations do not necessarily represent pathological findings. The idea has been changing with regards to the extracranial venous system.

DISCUSSION

A range of extracranial venous abnormalities have recently been reported, which could be classified as structural/morphological, hemodynamic/functional and those determined only by the composite criteria and use of multimodal imaging. The presence of these abnormalities usually disrupts normal blood flow and is associated with the development of prominent collateral circulation. The etiology of these abnormalities may be related to embryologic developmental arrest, aging or other comorbidities. Several CNS disorders have been linked to the presence and severity of jugular venous reflux. Another composite criteria-based vascular condition named chronic cerebrospinal venous insufficiency (CCSVI) was recently introduced. CCSVI is characterized by abnormalities of the main extracranial cerebrospinal venous outflow routes that may interfere with normal venous outflow.

SUMMARY

Additional research is needed to better define the role of the extracranial venous system in relation to CNS disorders and aging. The use of endovascular treatment for the correction of these extracranial venous abnormalities should be discouraged, until potential benefit is demonstrated in properly-designed, blinded, randomized and controlled clinical trials.

What went wrong? The flawed concept of cerebrospinal venous insufficiency

In 2006, Zamboni reintroduced the concept that chronic impaired venous outflow of the central nervous system is associated with multiple sclerosis (MS), coining the term of chronic cerebrospinal venous insufficiency ('CCSVI'). The diagnosis of 'CCSVI' is based on sonographic criteria, which he found exclusively fulfilled in MS. The concept proposes that chronic venous outflow failure is associated with venous reflux and congestion and leads to iron deposition, thereby inducing neuroinflammation and degeneration. The revival of this concept has generated major interest in media and patient groups, mainly driven by the hope that endovascular treatment of 'CCSVI' could alleviate MS. Many investigators tried to replicate Zamboni's results with duplex sonography, magnetic resonance imaging, and catheter angiography. The data obtained here do generally not support the 'CCSVI' concept. Moreover, there are no methodologically adequate studies to prove or disprove beneficial effects of endovascular treatment in MS. This review not only gives a comprehensive overview of the methodological flaws and pathophysiologic implausibility of the 'CCSVI' concept, but also summarizes the multimodality diagnostic validation studies and open-label trials of endovascular treatment. In our view, there is currently no basis to diagnose or treat 'CCSVI' in the care of MS patients, outside of the setting of scientific research.

Heart disease, overweight, and cigarette smoking are associated with increased prevalence of extra-cranial venous abnormalities

OBJECTIVES

Most of the extra-cranial venous abnormalities have been previously described as truncular venous malformations. In this hypothesis-driven study, we evaluated possible association of risk/protective factors with the presence of truncular and functional venous abnormalities in internal jugular veins (IJVs) in a large cohort of volunteers without known central nervous system (CNS) pathology.

METHODS

The study included 240 controls who underwent physical and Doppler sonography (DS) examinations for the presence of intra- and extra-luminal structural and functional abnormalities of the IJVs, and were assessed with a physical examination and structured environmental questionnaire for demographic characteristics, presence of autoimmune and other concomitant diseases, vascular risk factors, environmental factors, and habits. Logistic regression analysis was used to test which risk/protective factors were associated with the presence and number of extra-cranial venous abnormalities.

RESULTS

Subjects with heart disease (P<0·001), overweight (P = 0·005), and smoking (P = 0·016) had a significantly increased number of intra-luminal structural venous abnormalities. Presence of heart disease increased the risk of a malformed valve 12·9 times (95% CI: 5·4-31·3, P<0·001), while smoking increased it 2·21 times (95% CI: 1-4·9, P = 0·033). Being overweight (P = 0·003), a history of mononucleosis (P = 0·012) and smoking (P = 0·042) increased risk for presence of a flap. No association was found between the investigated risk factors and extra-luminal or functional venous abnormalities. However, use of dietary and herbal supplements had a protective role for the presence of functional venous abnormalities.

CONCLUSIONS

There is a close association between intra-luminal, structural, extra-cranial, venous system pathology and the presence of heart disease, overweight, and smoking.

Risk factors for chronic cerebrospinal venous insufficiency (CCSVI) in a large cohort of volunteers

Background

The role of intra- and extra-cranial venous system impairment in the pathogenesis of various vascular, inflammatory and neurodegenerative neurological disorders, as well as in aging, has not been studied in detail. Nor have risk factors been determined for increased susceptibility of venous pathology in the intra-cranial and extra-cranial veins. The aim of this study was to investigate the association between presence of a newly proposed vascular condition called chronic cerebrospinal venous insufficiency (CCSVI) and environmental factors in a large volunteer control group without known central nervous system pathology.

Methods and Findings

The data were collected in a prospective study from 252 subjects who were screened for medical history as part of the entry criteria and participated in the case-control study of CCSVI prevalence in multiple sclerosis (MS) patients, and then were analyzed post-hoc. All participants underwent physical and Doppler sonography examinations, and were assessed with a structured environmental questionnaire. Fullfilment of ≥2 positive venous hemodynamic (VH) criteria on Doppler sonography was considered indicative of CCSVI diagnosis. Risk and protective factors associated with CCSVI were analyzed using logistic regression analysis. Seventy (27.8%) subjects presented with CCSVI diagnosis and 153 (60.7%) presented with one or more VH criteria. The presence of heart disease (p = .001), especially heart murmurs (p = .007), a history of infectious mononucleosis (p = .002), and irritable bowel syndrome (p = .005) were associated with more frequent CCSVI diagnosis. Current or previous smoking (p = .029) showed a trend for association with more frequent CCSVI diagnosis, while use of dietary supplements (p = .018) showed a trend for association with less frequent CCSVI diagnosis.

Conclusions

Risk factors for CCSVI differ from established risk factors for peripheral venous diseases. Vascular, infectious and inflammatory factors were associated with higher CCSVI frequency.

Chronic cerebrospinal venous insufficiency: does ultrasound really distinguish multiple sclerosis subjects from healthy controls?

OBJECTIVES

To investigate the differences between multiple sclerosis (MS) and control subjects by using extracranial venous grey-scale, colour and spectral Doppler ultrasound.

METHODS

The study included 62 subjects with a definitive diagnosis of MS and 54 control subjects. The cross sectional area (CSA), reflux during Valsalva manoeuvre, presence or absence of flow in the internal jugular vein (IJV) were assessed in upright and supine positions. The IJV and vertebral vein (VV) flow volumes (BFV) were also studied.

RESULTS

Reflux in the IJV, an upright CSA greater than a supine CSA, and the presence or absence of flow in the IJV were not different between MS and control subjects. A CSA ≤ 0.3 cm(2) was observed to be significantly higher in MS subjects. The IJV BFV was not significantly different between the groups; however, the VV BFV was significantly higher on the right side and lower on the left side in MS subjects.

CONCLUSIONS

Our use of ultrasound criteria reported in the literature for MS reveals differences between healthy controls and MS subjects that also overlap. Our experience suggests that Doppler ultrasound may not be clinically reliable and more studies are needed to clarify its role, if any. Key Points • Chronic cerebrospinal venous insufficiency is a controversial topic in multiple sclerosis. • Ultrasound assessment of extracranial veins has yielded different results in the literature. • These differences may be due to dependence on Doppler and selection bias. • We found variations in vertebral vein flow in patients with multiple sclerosis.

Quantitative ColourDopplerSonography evaluation of cerebral venous outflow: a comparative study between patients with multiple sclerosis and controls

Background

Internal Jugular Veins (IJVs) are the principle outflow pathway for intracranial blood in clinostatism condition. In the seated position, IJVs collapse, while Vertebral Veins (VVs) increase the venous outflow and partially compensate the venous drainage. Spinal Epidural Veins are an additional drainage pathway in the seated position. Colour- Doppler-Sonography (CDS) examination is able to demonstrate IJVs and VVs outflow in different postural and respiratory conditions. The purpose of this study was to evaluate CDS quantification of the cerebral venous outflow (CVF) in healthy subjects and patients with multiple sclerosis (MS).

Methodology/Principal Findings

In a group of 27 healthy adults (13 females and 14 males; mean age 37.8±11.2 years), and 52 patients with MS (32 females and 20 males; mean age 42.6±12.1 years), CVF has been measured in clinostatism and in the seated position as the sum of the flow in IJVs and VVs. The difference between CVF in clinostatism and CVF in the seated position (ΔCVF) has been correlated with patients' status (healthy or MS), and a number of clinical variables in MS patients. Statistical analysis was performed by Fisher's exact test, non-parametric Mann-Whitney U test, ANOVA Kruskal-Wallis test, and correntropy coefficient.

The value of ΔCVF was negative in 59.6% of patients with MS and positive in 96.3% of healthy subjects. Negative ΔCVF values were significantly associated with MS (p<0.0001). There was no significant correlation with clinical variables.

Conclusions/Significance

Negative ΔCVF has a hemodynamic significance, since it reflects an increased venous return in the seated position. This seems to be a pathologic condition. In MS patients, a vascular dysregulation resulting from involvement of the autonomous nervous system may be supposed. ΔCVF value should be included in the quantitative CDS evaluation of the cerebral venous drainage, in order to identify cerebral venous return abnormalities.