Venous occlusion plethysmography in patients with post-thrombotic venous claudication

Venous Claudication: a Scoping Review of the Pathophysiology and Clinical Importance

OBJECTIVE

Venous claudication (VC) is under studied, often being excluded from clinical trials and scales. The purpose of this scoping review was to give a historical perspective of VC and analyse the prevalence, pathophysiological aspects, and clinical implications.

METHODS

An extensive search of the books and databases (PubMed, MEDLINE, Scopus, and Cochrane) was performed from inception until October 2021. Studies were considered eligible provided they reported on the topics of interest, whereas strict exclusion criteria with regards to the studied sample of patients, year of publication, or location of the obstruction could not be applied, because of the limited relevant literature.

RESULTS

Twenty nine articles were included. VC is found almost exclusively in patients with iliofemoral obstruction. Prevalence was reported in seven studies having a wide range from 10.6% to 74.0%. Dominant findings include increased venous volume and pressure. Pressure in capillaries also rises subsequently causing compartment oedema and increased intramuscular pressure resulting in tissue ischaemia and hypoxia. The time required for the venous pressure to return to the pre-exercise levels in the affected limbs is prolonged compared with normal (39.1 ± 14.4 seconds vs. 1.1 ± 1.1 seconds).

CONCLUSION

VC is an important symptom of venous outflow obstruction that is under studied, and merits further recognition. Better understanding of the pathophysiology will be achieved through investigations at tissue level. Diagnosis and improvement after treatment should be reported in an objective and standardised manner.

Overview of the Assessment of Endothelial Function in Humans

The endothelium is recognized to play an important role in various physiological functions including vascular tone, permeability, anticoagulation, and angiogenesis. Endothelial dysfunction is increasingly recognized to contribute to pathophysiology of many disease states, and depending on the disease stimuli, mechanisms underlying the endothelial dysfunction may be markedly different. As such, numerous techniques to measure different aspects of endothelial dysfunction have been developed and refined as available technology improves. Current available reviews on quantifying endothelial dysfunction generally concentrate on a single aspect of endothelial function, although diseases may affect more than one aspect of endothelial function. Here, we aim to provide an overview on the techniques available for the assessment of the different aspects of endothelial function in humans, human tissues or cells, namely vascular tone modulation, permeability, anticoagulation and fibrinolysis, and the use of endothelial biomarkers as predictors of outcomes.

A comparison of magnetic resonance venography findings and venous occlusion plethysmography variables in postthrombotic syndrome

Objective The relation between venous morphology and venous function in postthrombotic syndrome is poorly understood. The aim of this study was to compare obstruction and collateralization as seen with magnetic resonance venography with variables of venous occlusion plethysmography in patients with postthrombotic syndrome. Methods Medical records, magnetic resonance venography and venous occlusion plethysmography data were analyzed in 28 patients (33 legs). Magnetic resonance venography images were scored for degree of obstruction and collateralization in segments of pelvic and abdominal veins and correlated to venous occlusion plethysmography data. Results Obstruction of the inferior vena cava correlated with an overall increase of collaterals ( p < 0.001). The summary scores of collaterals or obstructions did not correlate with venous occlusion plethysmography variables. Relative expelled volume at 4 s correlated inversely with obstruction of the inferior vena cava ( p = 0.045) and vertebral collateralization ( p = 0.033). Conclusions Modest correlations were found between magnetic resonance venography scores and venous occlusion plethysmography variables. Prospective studies with refined scoring and magnetic resonance venography techniques may increase our knowledge further.