|Year : 2022 | Volume
| Issue : 2 | Page : 156-162
Quantification of Hemodynamic Parameters in Primary Great Saphenous Reflux using Colour Doppler in Clinical Settings and Effect of GSV Ablation on the Venous Arterial Flow Index
Manvendu Jha1, Ruchira Mukherji2, Vishwajeet Mopagar3, Kirti Kumari4
1 Department of Surgery, Division of Vascular Surgery, Army Base Hospital, Srinagar, India
2 Department of Radiodiagnosis and Imaging, Medical Officer, Army Base Hospital, Srinagar, India
3 Preventive Medicine Statistics and Station Health Organization, Medical Officer, Army Base Hospital, Srinagar, India
4 Department of Surgery, Army Base Hospital, Srinagar, India
|Date of Submission||05-Nov-2021|
|Date of Decision||26-Nov-2021|
|Date of Acceptance||01-Dec-2021|
|Date of Web Publication||13-Jun-2022|
Department of Surgery, Division of Vascular Surgery, Army Base Hospital, Srinagar
Source of Support: None, Conflict of Interest: None
Purpose: The aim of our study was to quantify venous reflux in outpatient settings using color Doppler and document objective improvement in hemodynamic parameters post ablation. Methods: Venous reflux was measured using color Doppler using venous-arterial flow index (VAFI), recirculation index (RCI), and percentage diameter change (PDC) (n = 30) and compared with healthy volunteers (n = 30), adjusted for age, sex, and body mass index (BMI). Patients with concomitant peripheral arterial disease (PAD), past history of deep venous thrombosis, chronic venous insufficiency, and venous ulcers were excluded from the study. Patients with reflux underwent RFA and VAFI was measured 6 months after treatment. Data were analyzed using IBM SPSS statistics software version 25. Tests of normality were applied before choosing statistical tests. Box-and-whisker plots with outliers were used to illustrate the difference between case and control groups. VAFI scores were compared pre- and postoperatively and Wilcoxon signed-rank test was applied for the comparison. P < 0.05 defined statistical significance. Results: Thirty patients with primary GSV reflux along with 30 healthy volunteers were adjusted for age, sex, and BMI. Clinical part of CEAP classification was C0 = 2, C1 = 6, C2 = 16, and C3 = 6 in reflux group and C0 = 26 and C1 = 4 in (n = 30) in healthy volunteers. There was a statistical difference in RCI, PDC, and VAFI across both groups (P < 0.5). In addition, VAFI decreased significantly after treatment at 6 months (1.38 preoperative to 0.95 postoperative, SD P < 0.5). Of the 30 patients, 21 had pain as the primary presenting symptom; 81% (17) reported a significant decrease in pain scores associated with hemodynamic improvement. Conclusion: RCI, PDC, and VAFI are accurate quantitative measurements of reflux in outpatient settings. VAFI is useful in objectifying the results of treatment. Symptomatic improvement in terms of pain score can be used to supplement the hemodynamic improvement though further substantiation of the above would be required in a larger cohort.
Keywords: Percentage diameter change, recirculation index, venous-arterial flow index, venous reflux
|How to cite this article:|
Jha M, Mukherji R, Mopagar V, Kumari K. Quantification of Hemodynamic Parameters in Primary Great Saphenous Reflux using Colour Doppler in Clinical Settings and Effect of GSV Ablation on the Venous Arterial Flow Index. Indian J Vasc Endovasc Surg 2022;9:156-62
|How to cite this URL:|
Jha M, Mukherji R, Mopagar V, Kumari K. Quantification of Hemodynamic Parameters in Primary Great Saphenous Reflux using Colour Doppler in Clinical Settings and Effect of GSV Ablation on the Venous Arterial Flow Index. Indian J Vasc Endovasc Surg [serial online] 2022 [cited 2022 Jul 3];9:156-62. Available from: https://www.indjvascsurg.org/text.asp?2022/9/2/156/347251
| Introduction|| |
Venous reflux is defined as a retrograde, downward flow in an incompetent vein connecting both poles of the ambulatory pressure gradient that occurs between the thigh and the lower leg veins during ambulation in an erect position and under the influence of gravitation. The source of reflux is situated in the thigh veins where a higher ambulatory pressure exists; the mouth of reflux is in the lower leg veins where a lower pressure prevails. Quantification of reflux with duration of reflux volume and not the localization of the retrograde flow in superficial or deep veins is the most important hemodynamic factor.,
The hemodynamic function of veins is drainage and other causes of drainage insufficiency include inefficiencies from a “private” circulation, rapid calf expansion on dependency, poor gravitational venous wall responsiveness, prolonged standing, and sitting. Majority of these functions can be expressed with numerical values, in contrast to reflux measurements, which cannot be reliably quantified. Reflux quantification using ultrasound is operator and maneuver dependent, and the cutoff value of > 0.5 s does not give quantification. That is why its use is only limited to establish the presence or absence of reflux. Thus, it is prudent to explore other parameters that quantify the degree of insufficiency. Selective abolition of superficial reflux in primary varicose veins restores normal venous hemodynamics, irrespective of the condition and in spite of the presence of large incompetent perforators of the lower leg. Documentation of improvement in preoperatively measured parameters will help in communicating the patients regarding the technical success of the procedure as well add objectivity to the whole scenario.
The aim of our study was to quantify superficial venous insufficiency in cases of primary varicose veins in clinical outpatient settings and document improvement in hemodynamic parameters post ablation for objective assessment.
| Methods|| |
Study population and design
This was a single-center, observational study. Retrospective analysis of prospectively collected data was done.
Venous reflux was quantified in thirty patients with primary great saphenous vein (GSV) reflux irrespective of their presenting symptoms by color Doppler at a peripheral center using venous-arterial flow index (VAFI), recirculation index (RCI), and percentage diameter change (PDC) of GSV. Similar hemodynamic parameters were measured in thirty healthy volunteers adjusted for age, sex, and body mass index (BMI). Patients with concomitant peripheral arterial disease (PAD), past history of deep venous thrombosis (DVT), chronic venous insufficiency, and venous ulcers were excluded from the study. All patients with primary GSV reflux underwent radiofrequency ablation (RFA) and VAFI was measured 6 months after treatment.
| Methodology|| |
GE Healthcare Logiq P5 Ultrasound Machine was used. All imagings were done using linear transducer 10 L (8–12MHz) probe at 12 MHz frequency with gain 50, sample volume 2, and AO 100% [Figure 1]. All patients were examined in standing and position to ensure maximum venous distention and subsequently in supine position, with the limb of interest in slight abduction and external rotation. The subjects were asked to bear weight on the contralateral leg to enable them to participate in maneuvers designed to elicit GSV reflux. SFJ was identified, marked, and reflux was elicited using color Doppler. Another point was marked on the GSV, 10 cm below the inguinal ligament which was used to measure the anteroposterior diameter of the inner wall of GSV in standing position, RCI, and postural diameter change PDC [Figure 2].
|Figure 1: Venous-arterial flow index is calculated by venous volume flow divided by Arterial volume flow. The diameter of the vessel is set by the operator and the machine calculated the area, time-averaged mean velocity and then the volume flow. In this example, the venous-arterial flow index is 469.2/119.3 = 3.93|
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|Figure 2: Recirculation index. The probe is kept 10 cm below inguinal ligament, Saphenofemoral junction (a) On calf compression, there is antegrade flow up the saphenous trunk (b). On relaxation, there is more reflux flow down (c). The recirculation index is reflux volume/antegrade volume|
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VAFI was calculated by imaging the common femoral vein (CFV) and artery to obtain volume flow (above SFJ). After these measurements, Greyscale and color Doppler examination of entire GSV and SSV was performed and presence of any varicose tributaries was identified [Figure 1] and [Figure 2].
The RCI was calculated by manually first compressing and then releasing the calf muscle. The probe was positioned over the specified point on GSV and the provoked antegrade and retrograde flow were recorded using pulsed-wave Doppler and RCI was calculated. Next, the patients were asked to lie down supine and a repeat measurement of inner wall of GSV was done to complete the measurement of PDC [Figure 1] and [Figure 2].
All patients with reflux underwent radiofrequency ablation of GSV using ClosureFast machine (Medtronic). Post procedure, they were followed up for 6 months and VAFI was measured at 6 months. Patients who presented with pain as their primary symptom were assessed pre and post procedure using a numeric pain rating scale.
Consent was obtained from all patients and healthy volunteers after explaining the procedure. Ethical committee clearance was obtained from appropriate authorities at our hospital.
Data were entered into Microsoft Excel sheet 2010 and analyzed using IBM SPSS statistics software version 25 (2017, USA). Tests of normality such as Kolmogorov-Smirnov and Shapiro-Wilk were applied before choosing statistical tests. Nonparametric tests were applied with median, interquartile range (IQR), and range to express the datasets. Box-and-whisker plots with outliers were used to illustrate the difference between case and control group and MannWhitney U-test was applied for comparison between the groups. VAFI scores were compared pre- and postoperatively and Wilcoxon signed-rank test was applied for the comparison. P < 0.05 defined statistical significance. The CFV, common femoral artery (CFA), and GSV diameters expressed in mm were compared between the study groups. Results were expressed as mean with 95% confidence interval and standard deviation. Independent sample t-test was applied to compare the mean difference between the study groups.
| Results|| |
Forty-two patients underwent RFA at our center from June 2019 to December 2020. Thirty patients with primary GSV reflux formed the cohort of our study along with 30 healthy volunteers adjusted for age, sex, and BMI. All patients were healthy male soldiers presently serving in high altitude areas with no known comorbidities. There were 26 smokers out of the 30 in reflux group as compared to 16 in nonreflux group. Mean age and BMI in patients and healthy volunteers were 33.8 and 23.4 and 31.2 and 22.5, respectively. In reflux group, right lower limb was involved in 14 cases, left limb in 12 cases, while two cases had bilateral involvement. In nonreflux group, measurement was done from the right limb in 26 cases. Four cases had telangiectasia involving the left limb, thus it was used for measurements. The mean VCSS score among the reflux group was 3. Clinical part of CEAP classification (in accordance of modified CEAP classification 2020) was C0 = 2, C1 = 6, C2 = 16, and C3 = 6 in reflux group (n = 30) and C0 = 26 and C1 = 4 in (n = 30) in healthy volunteers.
There was a statistically significant difference in PDC, VAFI, and RCI among reflux (case) and nonreflux (control) groups (P < 0.05). Similarly, there was a significant difference in VAFI score among preoperative and postoperative study groups (P < 0.05) [Table 1], [Table 2] and [Figure 3], [Figure 4], [Figure 5].
|Table 1: Hemodynamic parameters measured preoperatively across two groups|
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There was a significant difference in the CFV and GSV diameter in reflux and nonreflux group (P < 0.05). Although there was an increase in the mean diameter of CFA in the reflux group, it was not found to be statistically significant [Table 1].
|Figure 3: Box-and-whisker plot comparing patients with reflux (case) and no reflux (control) with three hemodynamic tests; venous-arterial flow index, percentage diameter change, and recirculation index|
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|Figure 4: Box-and-whisker plot comparing preoperative and postoperative venous-arterial flow index scored in the reflux (case) group|
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|Figure 5: Box-and-whisker plot comparing the distribution of great saphenous vein, common femoral vein, and common femoral artery diameters in reflux (case) and nonreflux (control) group|
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Out of thirty patients who underwent treatment, 21 had presented with complaints of dull aching leg pain and cramps with or without complaints of cosmesis. Nine patients complained of cosmesis only in the form of visible distended veins. Seventeen of the 21 patients who had pain as the primary complaint (81%) reported symptomatic relief post procedure associated with decrease in pain scores and VAFI. Four patients (19%) continued to have dull aching pain in spite of documented decrease in VAFI.
| Discussion|| |
There has always been a discordance between symptomatology and clinical signs in venous diseases. The considerable overlap between venous symptoms reported by patients with chronic venous disease (CVD) and by patients with other diseases of the lower leg confirms lack of specificity of venous symptoms. Marston postulated that none of the venous symptoms are specific to venous disease and multiple etiologies may be confused with CVD. The Bonn Vein Study revealed that of the 62.1% of females and 49.1% of males who reported with leg symptoms, only 31.4% and 27.8% had features of venous disease with clinical class above C2, and only 21.0% had evidence superficial venous reflux., Post treatment, there is always an expectation of improvement in signs and symptoms; however, clinical outcomes may not reflect the same as clinical assessments of severity are largely qualitative. In these circumstances, hemodynamic parameters of disease and its reference values pre- and postoperatively may help in objective documentation of success or failure of treatment rather than relying only on subjective assessment.
Quantification of venous reflux has been documented in relation to various measured parameters as peak reflux velocity, flow volume at peak reflux, duration of reflux,, and reflux volume. In our study, we measured the hemodynamic parameters of RCI, PDC, and VAFI preoperatively and compared the values using similar parameters in healthy volunteers to substantiate the ability of these tests to identify venous reflux in patients and healthy individuals with statistically significant discriminative ability [Table 1], [Table 2] and [Figure 3], [Figure 4], [Figure 5].
RCI is a measure of both the antegrade saphenous volume and reflux volume which standardizes reflux measurements against antegrade flow. Lattimer et al. measured RCI in 16 limbs using manual and cyclical compression maneuvers and reported statistically significant values of RCI >1. However, 13 of their patients had clinical disease of C3 (CEAP) and above with VCSS of >7. They also compared RCI values using both manual and compression maneuvers and found values to be more accurate using cyclical compression. In a similar study by the same author, they compared RCI in patients and healthy volunteers with similar results as our study though they had few patients with C4a and C4b disease in their cohort.
In our study, we employed the manual compression maneuver as it was more feasible in outpatient settings. In the reflux group, the majority subset of patients were C3 (CEAP) and below and had primary GSV reflux [Figure 2]. To maintain uniformity in measurements among case and control (healthy volunteers) groups, patients were adjusted with respect to age, sex, and BMI and excluded patients with venous ulceration and patients with reflux at more than one level. The median RCI was 0.9 in healthy group as compared to 3.74 in patients with reflux [Table 1] and [Figure 3]. Similarly, the range and IQR across both the groups were highly significant. All these results were comparable to those described in the literature.
GSV diameter has been measured at different levels in various studies and documented to vary significantly in cases of reflux. Navarro et al. measured GSV diameter at seven different positions and found that a GSV diameter of 5.5 mm or less predicted the absence of abnormal reflux, while a diameter of >7.3 mm predicted critical reflux. They also correlated these values with other hemodynamic parameters as venous filing index (VFI) and residual venous fraction (RVF) measured using plethysmography. Mendoza et al. measured GSV diameters at saphenofemoral junction (SFJ) and proximal thigh and found similar correlations. However, they found GSV diameter measurement at the proximal thigh to be more sensitive in predicting venous incompetence. They documented mean GSV diameters of 3.7 and 6.3 mm in reflux and nonreflux group. In both these studies, measurements were made in a standing position. In our study, we measured the diameter in proximal thigh 10 cm below the SFJ and found median GSV diameters of 4 and 5 mm in the respective groups [Table 1]. However, we measured the diameters in the supine position also and documented PDC as a quantitative parameter of hemodynamic significance [Figure 3] and [Figure 5].
PDC has been defined as a percentage change in inner diameter of the saphenous trunk from standing to lying position. It is a reflection of severity of venous remodeling and thus postulated to be useful in classifying the severity of CVD. It is measured at the same point as RCI. We took PDC >22% as normal value. Van der Velden et al. measured PDC in 193 limbs with primary GSV, anterior accessory saphenous vein, or small saphenous vein reflux, and 48 control limbs without ST reflux. The median PDC of the saphenous trunk was 19% in limbs with reflux as compared with 24% in control limbs. They also documented low values of PDC with old age, increase in BMI, and increase in severity of venous disease (C4–C6), most probably due to a decrease in compliance of the vein.
We reported a median PDC of 12.15% and 28.85% in reflux and control limbs, respectively [Table 1] and [Figure 3]. Furthermore, to negate the confounding effects of age, BMI, and severe venous disease, both groups were adjusted for the same and cases of venous ulceration and postthrombotic syndrome were excluded.
Both RCI and PDC can be used to measure and predict venous insufficiency to similar levels of severity; however, since their measurement is done on individual veins, it becomes a matter of debate if they can be extrapolated to represent the global venous hemodynamics. Furthermore, from a clinical point of view, their main disadvantage is that they cannot be measured postoperatively/GSV ablation. Although it has been reported that RCI can be measured in incompletely obliterated saphenous segments, in saphenous sparing surgeries, post crossectomy, and both PDC and RCI can be measured in distal nonablated GSV segments, their role in these situations has not been documented so far. In our study, we measured all the three parameters RCI, PDC, and VAFI preoperatively to quantify the reflux as well postoperatively document VAFI to record any hemodynamic improvement post-GSV ablation using RFA.
VAFI was first described by Kahle et al. under the assumption that venous hemodynamics is influenced by arterial blood flow characteristics, the relation between venous (VFV) and arterial volume flow (VFA) as a quotient was calculated as a quantitative hemodynamic pattern for interindividual comparison. The results of the study confirmed this ratio (the VAFI) as a suitable means of grading the severity of venous insufficiency. They measured VAFI in four subsets of patients ranging from C0 disease to postthrombotic syndrome and found significant differences as compared to the healthy group.
Kahle et al. measured pre- and postoperative VAFI in 46 patients with varicose veins who underwent varied modes of treatment. In all patients, there was a significant improvement (VAFI decreased from 1.19 to 0.86 after 2 weeks and 0.77 after 8 weeks) (P < 0.001). It was concluded that for quantifying the hemodynamic effect of intervention, VAFI would be the better parameter. Similarly, Knuth Ras et al. treated 133 patients with complete GSV insufficiency using endovenous laser therapy (EVLT) and assessed outcomes using VAFI and digital photoplethysmography (DPPG) at 3 and 12 months, respectively. They reported significant postoperative improvement in VAFI at 3 and 12 months after EVLT (P <.001). Venous refilling time (DPPG) accordingly increased from 20.0 to 36.9 s (P <.001) 3 months postoperatively. They concluded that EVLT improves hemodynamic alterations in people with incompetent GSV's and VAFI might be a suitable diagnostic tool to quantify venous hemodynamics in people with varicose veins.
In our study, we treated our patients by RFA of GSV using ClosureFast machine and measured VAFI before intervention and 6 months after intervention. The mean VAFI and IQR in the groups were 1.38 (1.29–1.48) and 0.95 (0.89–0.99) (P < 0.05) [Table 2] and [Figure 3], [Figure 4]. Only difference was that our patient population, had only Primary GSV reflux and disease subset was limited to C3 according to CEAP classification. Thus, it can be safely proposed that irrespective of the method employed to treat GSV, there is an improvement in the venous hemodynamics which can be documented using VAFI.
The main advantage of VAFI with reference to other parameters is that it can be measured postoperatively. Since clinical and hemodynamic severity is poorly related to venous insufficiency, improved parameters after treatment can be used in clinical practice irrespective of improvement in symptoms of the patient to ascertain the success of treatment procedure. Furthermore, measurements in CFV have been proposed to be a better predictor of quantitative parameters in venous insufficiency, thus this measurement can be a part of global assessment. In addition, it is readily available, easily reproducible, can be performed in outpatient settings, and is maneuver independent. Although plethysmographic measurements can also be used as a global assessment tool, be measured both pre- and postoperatively, and have been extensively validated, they are maneuver dependent and not readily available. In comparison to plethysmography, VAFI measurement is significantly less time consuming and can be repeated as often as necessary without discomfort for the patient.
Although correlating hemodynamic improvement with clinical improvement has not been encouraged in available literature due to nonspecific nature of venous symptoms, we documented a significant decrease in pain scores associated with improvement in VAFI post-GSV ablation. However, it cannot be used as a benchmark provided the extremely small cohort in our study.
The major drawback of VAFI is lack of its documentation in patients with concomitant PAD. Since the basis of this measurement is on assumption of arterial inflow characteristics, none of the published literature has measured VAFI in patients with PAD. In our study also, we have excluded patients with PAD. Maybe a comparative study in future will be able to define and validate this concept. Also, it does not have adequate discriminative value, in addition to lack of validation in clinical settings which further is a hindrance in its widespread clinical application.
Another finding in our study which corroborated with existing literature was a statistically significant increase in CFV diameter in reflux group as compared to healthy volunteers. Furthermore, a decrease in diameter was recorded post ablation. Similar findings were seen with CFA diameter; however, they were not statistically significant. AltThough decrease in CFV diameter post intervention has been documented, we could not find any such thing for CFA.
| Conclusion|| |
In cases of venous insufficiency once reflux is identified, it should be objectively documented. RCI, PDC, and VAFI are accurate quantitative measurements of reflux and are easily reproducible in outpatient settings. VAFI is useful in objectifying reflux as well as the results of treatment, is easily reproducible and maneuver independent, and can be readily used in outpatient settings. Symptomatic improvement in terms of pain score can be used to supplement the hemodynamic improvement though further substantiation of the above would be required in a larger cohort.
Limitations of our study
Although we have tried to objectively document reflux and reproduce it in outpatient settings and document clinical improvement using pain score, we did not extrapolate it by assessing the quality of life index parameters. In published literature, VFI has been the most abundantly documented criteria and it can also be measured both pre- and postoperatively, but we did not have this facility at our peripheral center. Furthermore, its use in clinical settings is quite cumbersome, yet its usefulness cannot be overlooked.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1], [Table 2]