Midterm varicose vein recurrence rates after endovenous laser ablation: comparison of radial fibre and bare fibre tips

Abstract

OBJECTIVES

We evaluated and compared midterm recurrence results of our patients with great saphenous vein insufficiency who were treated with a 1470-nm diode laser using 2 different types of fibre catheter kits.

METHODS

A total of 61 consecutive patients were treated between 2013 and 2014 with a bare fibre (BF) tip (BF group) and 60 consecutive patients were treated with a radial fibre (RF) tip (RF group) from 2014 to 2016. First-year venous clinical severity scores (VCSSs) were compared with VCSS before endovenous laser ablation and at the first-month follow-up. Patients were examined for recurrence and classified according to the system developed by Stonebridge.

RESULTS

There was no significant difference between the 2 groups in terms of VCSS. Examination with Doppler ultrasonography showed no recurrence in the RF group, whereas recurrences were detected in 6 patients in the BF group, which was statistically significant (P = 0.028). All of the recurrences were type 1b (incompetent tributaries) varicose vein recurrences. The VCSS of the patients with recurrence were the same as the scores of patients without recurrence (0.5 ± 0.55).

CONCLUSIONS

Varicose vein recurrence was more often seen in the BF group than in the RF group. Recanalization-induced and neovascularization-induced recurrences were not found in either group. Saphenofemoral side branch-induced recurrence was more significant in the group treated with the BF tip.

INTRODUCTION

Seventy percent of varicose veins occur due to the insufficiency of the saphenofemoral junction (SFJ) and the great saphenous vein (GSV). This disease can be treated conservatively with venoactive drugs and/or compression stockings or with surgical therapy (stripping and/or high ligation) when indicated. In addition to these conventional treatment modalities, endovenous laser ablation (EVLA) is a novel minimally invasive treatment that has been used more frequently in recent years [1]. EVLA causes thermal damage to the venous wall, which leads to fibrotic occlusion of the GSV. Fibrotic occlusion occurs due to endothelial damage and collagen denaturation in the media [2]. Although the early results of EVLA are very successful, the mid- and long-term results are controversial. In this study, we evaluated and compared the midterm recurrence results of our patients with GSV insufficiency who were treated with a 1470-nm diode laser using 2 different fibre catheter kits.

MATERIALS AND METHODS

Retrospective data analysis was performed in patients who underwent EVLA with a 1470-nm diode laser (Ceralas, Biolitec AG, Vienna, Austria) between 2013 and 2016. The diagnosis for this treatment was insufficiency of the SFJ and the GSV (reflux time ≥ 0.5 s and GSV diameter ≥ 5 mm). Patients treated simultaneously for perforating vein insufficiency or short saphenous vein insufficiency and patients without first-year follow-up data were excluded from the study. A total of 121 patients were included in the study. The patients were given information about the aim and content of the study; written informed consent was obtained from all subjects before initiating any study procedures. All procedures were performed by a single experienced endovenous surgeon who used 2 different fibre kits. Bare fibres (BF) (ELVeS Plus kit, Biolitec AG) were used in 61 patients (BF group) and radial fibres (RFs) (ELVeS Radial kit Biolitec AG) (RF group) were used in 60 patients (RF group) (Fig. 1). The choice of fibre catheter was time-specific. BFs were used between 2013 and 2014, and RFs were used between 2014 and 2016. All patients were treated successfully, and no complications (e.g. deep vein thrombosis, pulmonary embolism, endothermal heat-induced thrombosis) developed during and after the procedures. Criteria for successful treatment included the following: at the 1-month follow-up, decreased venous clinical severity scores (VCSSs) [3], an occluded GSV with substantial (>30%) reduction in diameter and absence of flow within the treated segment on Doppler ultrasonography (USG). The VCSS includes 10 clinical features of venous disease (pain, varicose veins, venous oedema, skin pigmentation, inflammation, induration, number of active ulcers, duration of active ulceration, size of the ulcer and use of compression therapy), each scored from 0 to 3. It can be used to assess changes in response to treatment [3]. Fifty-two patients were men and 69 were women. The mean age was 42 (±15.2) years.

Figure 1:

Patient flow chart. BF: bare fibre; EVLA: endovenous laser ablation; GSV: great saphenous vein; PV: popliteal vein; RF: radial fibre; SFJ: saphenofemoral junction; SSV: small saphenous vein.

After obtaining the patient's medical history and performing a physical examination, the first-year VCSSs were recorded. These data were compared with VCSSs obtained before EVLA and at the first-month follow-up. The SFJ and GSV of the patients were examined for recurrence with a Doppler USG system (SonoSite Micromax ultrasound, FujiFilm SonoSite, Bothell, WA, USA). Varicose veins with recurrence were classified according to Stonebridge et al. [4]. Reflux >0.5 s was considered pathological. Doppler ultrasound was performed without knowledge of which type of fibre was used. Thus, blinding was provided during evaluation. For patients who had EVLA applied to both extremities, these data were recorded separately for each extremity.

Endovenous laser ablation procedure and process variations for both fibre catheters

All patients were monitored. Patients were given only oxygen support and intravenous midazolam for sedation. After venous Doppler mapping, a percutaneous entry point was chosen that was the point at which no reflux was seen (usually around or just below the knee). The GSV was punctured with a 19-gauge needle and the guidewire was placed. During the use of the BF, a long sheath was placed over the guidewire so that it would be located 2 cm below the SFJ. The BF was advanced through this sheath and locked. During the use of an RF, a 6-Fr introducer sheath was inserted inside the GSV over the guidewire. The RF was inserted directly through this sheath, and its tip was placed into the SFJ. Thus, the tip of the BF was placed 2 cm below the SFJ, and the tip of the RF was at a distance of 0–1 cm from the SFJ. Under the guidance of Doppler USG, the EVLA procedure was started after administration of 10–15 ml tumescent local anaesthesia on each 1-cm section in the perivenous environment (9% normal saline 1000 cc, 2% prilocaine 40 ml, 1:1000 adrenaline 1 ml, 10 mEq NaHCO₃). During the use of the BF, 12 watts of continuous mode laser energy was applied at a rate that corresponds to a linear endovenous energy density capable of applying 90 Joules/cm at the first 10-cm section (proximal portion of the GSV above the knee). For patients requiring intervention after the first 10-cm section, laser energy was used at a rate of 80 Joules/cm above the knee and 60 Joules/cm below the knee. During the use of the RF, lower energy was preferred. In the same mode and rate, energy at a rate of 80 Joules/cm was used in the first 10-cm section, whereas 60 Joules/cm was used for subsequent sections above and below the knee [5]. After the procedure, the closure of the SFJ and the GSV was checked in all segments using Doppler USG. A compression bandage was applied to all patients for 24 h. A single dose of prophylactic low-molecular-weight heparin was administered subcutaneously 4 h after the procedure. Patients were discharged on postoperative day 1. The patients were given 30- to 40-mmHg compression stockings. They were instructed to wear them continuously for 10 days and to walk regularly throughout the recovery period [6]. Analgesic medications (100 mg of flurbiprofen/2 times a day) was prescribed to the patients for use when needed.

Statistical analyses

All data obtained from the study were analysed with the Statistical Package for the Social Sciences 16.0 for Windows (SPSS Inc., Chicago, IL, USA). Data were expressed as mean ± standard deviation. A two-group comparison for VCSS was performed using the Mann–Whitney U-test, and the recurrence rates were compared using the Fisher’s exact test. P-value <0.05 was considered to be a statistically significant indicator of differences.

RESULTS

This study included 61 patients (36 women and 25 men) in the BF group and 60 patients (33 women and 27 men) in the RF group. There was no significant difference between the BF and RF groups in terms of demographic characteristics, the diameter of SFJ and GSV, the Clinical, Etiological, Anatomical and Pathological (CEAP) classification and VCSS data before the EVLA procedure (Table 1). The most common clinical feature of VCSS in both groups was afternoon oedema above the ankle. This was followed by multiple varicose veins (≥3 mm) confined to the calf or thigh. Daily pain with moderate activity limitation and occasional analgesic use were the third most frequently occurring clinical feature in both groups. During the EVLA procedure, a technical success rate of 100% was achieved in both groups (after the procedure, an enlarged non-compressible GSV, minimally decreased in diameter, and no flow seen within the occluded GSV lumen on Doppler examination), although a lower energy level was applied to the patients in the RF group based on the literature [5]. No recurrence was detected in the patients following a Doppler ultrasound examination at the first-month follow-up. VCSSs showed dramatic improvement in both groups in the first month. There was no significant difference between the 2 groups in terms of VCSSs in the first month (Table 2).

Table 1:

Preoperative patient demographics

	BF group (n = 61)	RF group (n = 60)	P-value
Mean age (years)	40.57 ± 14.87	43.03 ± 15.51	0.51
Gender (male/female)	25/36	27/33
Mean reflux time at SFJ (s)	4.84 ± 1.97	5.07 ± 1.88	0.56
Mean GSV diameter (mm)
SFJ level	10.81 ± 2.89	11.16 ± 3.2	0.54
Knee level	7.67 ± 1.78	8.02 ± 1.98	0.51
CEAP classification (number of limbs)
C2	29	30
C3	32	29
C4	4	5
C5	0	0
C6	0	0
VCSS (0–30) (mean)	4.72 ± 1.98	5.13 ± 2.07	0.25

BF: bare fibre; CEAP: Clinical, Etiological, Anatomical and Pathological; GSV: great saphenous vein; RF: radial fibre; SFJ: saphenofemoral junction; VCSS: venous clinical severity score.

Table 2:

Patient follow-up data

	BF group (n = 61)	RF group (n = 60)	P-value
Postoperative EVLA success rate (%)	100	100
Postoperative complication rate (%)	0	0
First-month follow-up data
Number of varicose vein recurrences	0	0
Superficial epigastric vein	0	0
Superficial circumflex iliac vein	0	0
Superficial external pudendal vein	0	0
AASV	0	0
VCSS (0–30) (mean)	1.84 ± 1.02	2.03 ± 1.19	0.37
First-year follow-up data
Number of varicose vein recurrences	6	0	0.028
Superficial epigastric vein	1a	0
Superficial circumflex iliac vein	0	0
Superficial external pudendal vein	0	0
AASV	5a	0
Length of the stump (cm) (mean)	1.21 ± 0.34	0.49 ± 0.45	<0.001
Completely closed SFJ	0	19
VCSS (0–30) (mean)	0.54 ± 0.62	0.55 ± 0.62	0.81

^aConnected with the stump.

AASV: anterior accessory saphenous vein; BF: bare fibre; EVLA: endovenous laser ablation; RF: radial fibre; SFJ: saphenofemoral junction; VCSS: venous clinical severity score.

An additional improvement detected in VCSSs at the first-year follow-up was the lack of a significant difference between the 2 groups in terms of VCSSs. In both groups, some patients reported daily pain during the first month of follow-up, whereas during the first year of follow-up, no patients reported daily pain. Evening ankle oedema or leg pain after standing for a long time was the most common clinical feature in the first year. Doppler USG examination showed no recurrence in the RF group, whereas a recurrence was detected in 6 patients in the BF group (6 extremities), which was statistically significant (P = 0.028). All of the recurrences were type 1b (incompetent tributaries = 1 superficial epigastric vein and 5 anterior accessory saphenous veins) varicose vein recurrence [4] (Table 2).

In 19 patients of the RF group, the SFJ was completely closed. The GSV residual stump was 0 cm in these 19 patients. In the remaining patients of the RF group, the GSV residual stump was present in a minimal length (mean: 0.49 cm; min: 0 cm; max: 1.5 cm). In contrast, in the BF group, there was no completely closed SFJ, and the residual stump was much longer (mean 1.2 cm; min: 0.5 cm; max: 1.7 cm) (P < 0.001) (Table 2).

When we evaluated the VCSSs of the patients with recurrence, we found they were improved compared with the first-month scores. These scores were at the same level as those of the first-year VCSSs of patients without recurrence (0.5 ± 0.55).

DISCUSSION

In the literature, the reports of recurrences rate after varicose vein surgery are highly variable (20–50%) [7, 8]. Kostas et al. [7] categorized the reasons for recurrence into 4 main groups. They called the first group ‘tactical errors’. This group includes recurrences that occur after incorrect or incomplete surgical interventions due to misdiagnosis or incomplete diagnosis in the preoperative period (e.g. undiagnosed double GSV or the presence of a double short saphenous vein, undiagnosed additional perforating vein insufficiency). They called the second group ‘technical errors’, which includes recurrences that, despite a complete and correct diagnosis, were caused by incomplete surgical interventions. The third group was called ‘disease progression’. This group includes recurrences originating from veins that were not diseased during the first surgical treatment and that became varicose over time due to the progressive nature of the disease. The last group was called ‘neovascularization’, which means the formation of new vessels. The new vessels form between the main femoral vein and the GSV stump or its side branches. These new vessels can lead to newly formed varicose veins.

Varicose veins recur after the EVLA procedure for several reasons. The major reason is the recanalization of the veins over time due to poor formation of fibrosis, which occurs because of insufficient thermal damage to the vein wall due to the use of low energy during the procedure [9–11]. To avoid this, based on recommendations from studies in the literature [12], we recommend using high energy (≥70 J/cm) during the EVLA procedure.

Another reason for recurrence after EVLA is that the side branches of the SFJ remain open during and after the procedure [13]. In 6 of our patients, we identified recurrences that originated from these saphenofemoral side branches. To avoid this, some surgeons recommend performing high ligation in addition to the EVLA procedure [14, 15]. Studies that compare EVLA with and without high ligation have shown the superiority of an additional high ligation in EVLA. These studies have shown that an additional high ligation prevents recurrences from originating from the saphenofemoral side branches [16, 17]. In these studies, EVLA was performed with a BF tip. We do not support the proposal of additional high ligation in EVLA, because high ligation is a risk factor for neovascularization [18].

Several hypotheses have been discussed as a cause of this neovascularization. The most common hypothesis is the secretion of angiogenic factors from the endothelial cells of the free endothelial surface of the open stump. The reason for this is the induction of hypoxia in the stump due to the ligation of the GSV at the SFJ [18, 19]. This hypothesis is supported by the positive results of various additional surgical interventions (wrapping of the SFJ stump with a polytetrafluoroethylene patch or a silicone patch, closure of the endothelial opening of the stump with suturing) performed in order to inhibit neovascularization [20–24]. In our study, we found no recurrence induced by neovascularization in either group.

The interesting result of our study was that we found recurrence of varicose veins from incompetent saphenofemoral side branches in 6 of the patients who were treated with BFs (all in direct connection with the residual GSV stump) and in none of the patients treated with RF (P = 0.028).

With a BF, the laser energy spreads forward, whereas with the RF, it spreads directly onto the vessel wall at an angle of 360 degrees [5]. This technological difference causes surgical differences between the 2 fibres during the EVLA procedure. Because the energy spreads forward with the BF, a safe distance must be created to prevent deep vein occlusion. Therefore, the BF catheter tip is placed 2 cm below the SFJ. In contrast to the BF, the RF does not require a safety distance, because the energy spreads directly onto the vessel wall. This factor allows the tip of the RF catheter to be placed into the SFJ. We believe that this technological difference is the reason for the interesting result that we mentioned above. Placing the tip of the RF catheter into the SFJ can lead to occlusion of the saphenofemoral side branches and can prevent recurrences originating from these branches. The GSV residual stump Doppler ultrasound findings from the RF group support our opinion. In 19 patients from this group, the SFJ was completely closed. In the remaining patients, the GSV residual stump was present in minimal length. In contrast, in the BF group, the SFJ was not completely closed, and the residual stump was much longer.

There was no significant difference between the 2 groups in terms of early and midterm VCSSs. When we evaluated the VCSSs of the 6 patients with recurrences, we found that they improved compared with the first-month scores. At the end of the first year, these scores were at the same level as those observed in the first year VCSSs of patients without recurrence. We believe that the reason for this is that the Doppler ultrasound recurrence findings do not yet have any symptomatic effects on the clinical severity. We think that these ultrasound-detected recurrences and their VCSSs will worsen with time.

CONCLUSION

At the first-year follow-up, varicose vein recurrence was more often seen in the BF group than in the RF group. Recanalization-induced recurrence and neovascularization-induced recurrence were not found in either group, whereas saphenofemoral side branch-induced recurrence occurred more often in the BF group. Although the results of our study show that the technological differences of the RF offer advantages in terms of saphenofemoral side branch-induced recurrence, the purpose of our study was not to show the superiority of the RF technology. According to the data we obtained from our study, changing the catheter type improved our results in terms of recurrence. Hence, we now prefer RF technology in our practice.

Conflict of interest: none declared.

Author contributions

Burcin Abud: Conceptualization; Data curation; Formal analysis; Funding acquisition; Investigation; Methodology; Project administration; Resources; Software; Supervision; Validation; Visualization; Writing—original draft; Writing—review & editing. Ayse Gul Kunt: Data curation; Investigation; Visualization.

Reviewer information

Interactive CardioVascular and Thoracic Surgery thanks Petre Vlah-Horea Botianu, Kanat Ozisik and the other, anonymous reviewer(s) for their contribution to the peer review process of this article.

ABBREVIATIONS

BF

Bare fibre

EVLA

Endovenous laser ablation

GSV

Great saphenous vein

RF

Radial fibre

SD

Standard deviation

SFJ

Saphenofemoral junction

USG

Ultrasonography

VCSS

Venous clinical severity score