Arterial and venous peripheral vascular assessment using wearable electro-resistive morphic sensors

Peripheral vascular diseases (PVDs) represent a significant burden on global human health and healthcare systems. With continued growth in obesity and diabetes, it is likely that the incidence of these conditions will increase. As many PVDs remain undiagnosed, low-cost and easy to use diagnostic methods are required. This work uses newly developed wearable electro-resistive morphic sensors to assess venous and arterial competence in the lower limbs of 36 healthy subjects. Comparison of this HeMo device was made to currently available benchtop light reflection rheography and photoplethymography devices. Results indicate that HeMo can detect the physiological signals of interest for both chronic venous insufficiency and peripheral arterial disease and all subjects were interpreted as healthy by each system. However, measurement repeatability of HeMo was highlighted as an issue that requires further system development. Furthermore, as HeMo captures changes in a section of limb circumference due to changes in underlying blood movement, rather than at a single point, the recorded signal is typically damped by comparison. This factor should be considered in any future developments.

Analysis of the postoperative hemodynamic changes in varicose vein surgery related with small saphenous vein reflux

PURPOSE

To evaluate the postoperative hemodynamic changes in varicose vein surgery related with SSV reflux using APG.

METHODS

Totals of 181 limbs and 178 patients who underwent high ligation and stripping (HLS) (87 limbs), radiofrequency ablation (RFA) (43 limbs), or endovenous laser ablation (EVLA) (51 limbs) for SSV reflux from 1995 to 2022 were enrolled. We measured venous volume (VV), venous filling index (VFI), ejection fraction (EF), and residual volume fraction (RVF) preoperatively and at postoperative one and 6 months.

RESULTS

Comparing preoperative results to those at postoperative 1 month, the reduction rates of VV, VFI, and RVF were 27, 53, and 31%, while EF increased by 18% (p < 0.001). Comparing preoperative and postoperative 6 month, the reduction rates of VV, VFI, and RVF were 27, 45, and 35%, while EF increased by 27% (p < 0.001).

CONCLUSIONS

There were hemodynamic improvement in the lower leg after varicose vein surgery including HLS, RFA, and EVLA.

Correlation between reflux time and venous clinical severity score in patients undergoing saphenous vein ablation: A prospective study

OBJECTIVES

It is unclear whether reflux time independently correlates with severity of symptoms in patients with great saphenous vein reflux.

METHODS

Eighty patients (mean age 64+/-12.7 years, 56% female) undergoing great saphenous vein (GSV) ablation for symptomatic reflux were assessed prospectively. Fifty-seven underwent ablation with radiofrequency, 23 with cyanoacrylate adhesive. Venous clinical severity score (VCSS) was assessed at, or prior to the time of ablation. The highest reflux time in the GSV was selected.

RESULTS

VCSS values ranged from 2 to 20 (median 7). Mean reflux time was 5.3 s (+/-3.3). The Spearman rank correlation yielded a value of rs = -0.123, p (2-tailed) = .279, which was not significant. The patients with concomitant deep vein reflux had higher VCSS (p < .05). Analysis of patients with only superficial vein reflux (n = 45) also demonstrated a poor correlation between VCSS and reflux time (rs = -0.051, p (2-tailed) = .741).

CONCLUSION

This prospective study did not demonstrate a correlation between reflux time and VCSS.

Comparison of Four Haemodynamic Tests that Quantify Superficial Venous Insufficiency

OBJECTIVES

Reflux assessment with ultrasound (U/S) is usually qualitative. Quantitative measurements of superficial venous insufficiency (SVI) include the venous arterial flow index (VAFI), recirculation index (RCI), venous filling index (VFI), and the postural diameter change (PDC) of the saphenous trunk. The aim was to investigate their relationship.

MATERIALS AND METHODS

This was an observational study performed on patients with varicose veins and hospital employees. Four haemodynamic parameters were measured in 21 legs from 16 subjects. Legs were divided into no reflux (n = 7) and reflux (n = 14). The VAFI is the U/S ratio of common femoral vein volume flow divided by the common femoral artery volume flow, performed supine. The RCI is the U/S ratio of reflux volume over antegrade volume within the saphenous trunk after calf compression, standing. The VFI is the rate of calf volume increase on dependency measured in mL/s, using air plethysmography. The PDC is the percentage reduction of the saphenous trunk diameter from standing to lying, using U/S.

RESULTS

The clinical part of the CEAP classification was: C₀ = 3, C₁ = 4, C₂ = 5, C₃ = 1, C_4a = 1, C_4b = 6, C₅ = 1. All four tests demonstrated significant differences between the two groups with minimal overlap (Mann Whitney U test): VAFI (p = .028), RCI (p < .0005), VFI (p = .001), and PDC (p = .014). Furthermore, significant correlations were observed with the tests: VAFI vs. RCI (r = .532, p = .015), VFI (r = .489, p = .025) and PDC (r = -.474, p = .030); RCI vs. VFI (r = .446, p = .043) and PDC (r = -.527, p = .014).

CONCLUSIONS

Superficial venous drainage insufficiency should not be confined to an U/S assessment of the presence of reflux, which is qualitative. Quantitative data may be provided using the VAFI, RCI, VFI, and PDC. Understanding why there are significant correlations among these parameters and the preferred objective reference test requires further work.

The Discord Outcome Analysis (DOA) as a Reporting Standard at Three Months and Five Years in Randomised Varicose Vein Treatment Trials

OBJECTIVES

Treatment success for chronic superficial venous insufficiency could be defined as an improvement in three domains: (i) disease specific quality of life, (ii) clinical severity, (iii) reflux. The aim was to report these at five years using a Venn diagram to profile the outcomes: a discord outcome analysis (DOA).

METHODS

Patients (n = 50 patients/legs in each treated group) were randomised to endovenous laser ablation (EVLA) with concurrent phlebectomies vs. ultrasound guided foam sclerotherapy (UGFS). Outcomes were assessed using three domains: (i) Aberdeen varicose vein questionnaire (AVVQ), (ii) venous clinical severity score (VCSS), (iii) venous filling index (VFI) of air plethysmography. Change scores were calculated by subtracting the final score after treatment from the baseline score before treatment to quantify the improvement. This was followed by a DOA profile for each patient where a discord was defined as the percentage of patients with a numerical deterioration in one or two domains.

RESULTS

The median [interquartile range] follow up was 68 [64-72] months. Follow up in all three domains was EVLA: 45/50, UGFS: 42/50. On ultrasound examination, GSV occlusion at some point above the knee was 93% for EVLA and 64% for UGFS (p = .001). There was no significant difference in improvement between the two treatment groups in the VCSS and the VFI. However, the EVLA group had a statistically significant AVVQ improvement (p = .004). Using a DOA, only 76% EVLA versus 60% UGFS had success in all three domains. Using improvement thresholds, this reduced to 54% and 39%, respectively. The commonest discord pattern was an improvement in the VCSS and VFI but deterioration in the AVVQ.

CONCLUSIONS

A DOA demonstrated that the definition of success is reduced if deterioration in one or two domains is taken into account. A DOA should be considered as a reporting standard for comparative analyses.

Gravitational venous drainage is significantly faster in patients with varicose veins

OBJECTIVES

It has been proposed that varicose veins may be caused by a degree of impeded proximal venous drainage (pelvic venous obstruction) in the same way that biological tubes dilate in response to an obstruction. The venous drainage index (VDI) of air-plethysmography (APG) was used to test this hypothesis. A dependency to elevation manoeuvre was used to provoke gravitational venous drainage. A rapid reduction in calf volume implied good drainage.

METHODS

This was a single centre, proof-of-concept study comparing gravitational venous drainage in varicose vein patients and controls. Leg filling and drainage manoeuvres (elevation to dependency and dependency to elevation) were performed three times per leg in 15 patients (7 male, 8 right) and 16 controls (3 male, 8 right). The VDI was measured in the same way the established venous filling index (VFI) is calculated to quantify filling: VDI = 90% of venous drainage volume (90VDV)/90% venous drainage time (VDT90).

RESULTS

The patients were significantly older at 58 (41-75) years versus the controls 47 (18-58), p = 0.001. There was no significant difference between the groups in weight, height, BMI or common femoral vein diameter. The patients were (C2 = 8; C3 = 1, C4 = 6), VCSS 4 (1-11) with a median refluxing proximal thigh saphenous diameter of 6 (5-11) mm. The median (inter-quartile range) VFI and VDI (both in mL/s) in the control tests (n = 48) were 1.3 (0.9-1.9) and 33.8 (21.5-55), respectively. The VFI and VDI in the patient tests (n = 41) were significantly faster at 6.2 (3.5-9.4), p < 0.0005, and 47.1 (36.1-66.3), p = 0.002, respectively. Adjusted to a standard mean for each leg, the reproducibility limits (×3) of the VDI was very good at 39.7 (95% CI: 36.5-42.9) in controls and 52.9 (95% CI: 49.7-56.1) in patients.

CONCLUSION

The VDI was significantly greater in patients with varicose veins compared to controls. It is unlikely that impeded gravitational drainage is a significant factor in the pathophysiology of varicose veins.

Validation of the Villalta scale in assessing post-thrombotic syndrome using clinical, duplex, and hemodynamic comparators

INTRODUCTION

The Villalta scale (VS) was developed by Prandoni and introduced as an abstract in 1994 as a disease-specific assessment questionnaire to diagnose and classify the severity of post-thrombotic syndrome (PTS). While validation using quality-of-life assessments and reproducibility have been reported as good, limited data exist as how the VS compares against generalized assessment tests in defining the severity of PTS. The aim of this study was to compare the VS against the Venous Clinical Severity Score (VCSS), the C of the CEAP classification, the Venous Segmental Disease Score (VSDS), and the Venous Filling Index (VFI) of air plethysmography.

METHODS

Baseline data generated from a recent single-center prospective clinical trial comparing graduated elastic compression stocking performance on 40 legs in 34 patients with PTS were analyzed. Ancillary data from this study were used to assess the measurement properties of the VS. All the legs had PTS defined as persisting leg symptoms/signs at least 6 months after a deep vein thrombosis with evidence of deep venous obstruction and/or deep venous reflux on duplex ultrasound. Unadjusted VS scores were used so patients with ulceration with a VS <15 were not automatically upgraded to a score of 15.

RESULTS

The number of legs by the C part of the CEAP classification was: C0 = 2, C2 = 1, C3 = 3, C4a = 12, C4b = 7, C5 = 12, and C6 = 3. The median (interquartile range) of age, VS, VCSS, VSDS, and VFI were 62 years (52-73 years), 10 (5-14), 8 (5-10), 5 (4-6.5), and 4.9 (2.8-7.9) mL/s, respectively. The VS had a highly significant and moderate-to-good correlation (Spearman) with the VCSS (r = .609; P < .0005) and the C of CEAP (r = .556, P < .0005). When the VFI was used as a hemodynamic benchmark, the VS correlation outperformed the other assessment tests (r = .499; P = .001). However, the VCSS correlation with the VFI was also significant (r = .480; P = .002). Surprisingly, the VSDS did not correlate with any assessment tests. No correlation could be detected within the VS between patient symptoms and their clinical signs. Correlations between the VS and the VCSS (r = .775) and C class (r = .779) improved when the VS patient-reported part was excluded.

CONCLUSIONS

These results indicate that the VCSS and the C of CEAP may also be useful in the assessment of PTS severity, and the VFI may provide a clinically meaningful hemodynamic evaluation. However, using the VFI as a reference, there was no essential difference between the VS and the VCSS.

Short-term gain for long-term pain? Which patients should be treated and should we ration?

Objectives:

Treatments of common conditions which do not affect mortality often become sidelined in the drive to improve efficiency and reduce costs. The rationing of patients is a divisive but crucial component to universal health care. How should this be accomplished?

Methods and Results:

In this article we examine the outcomes of various rationing methods in varicose veins.

Conclusions:

No method is perfect and treatment of symptoms and complications should remain the target for all physicians.