Fate of Great Saphenous Vein After Radio-Frequency Ablation: Detailed Ultrasound Imaging

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1 Fate of Great Saphenous Vein After Radio-Frequency Ablation: Detailed Ultraso... Sergio X Salles-Cunha; Hiranya Rajasinghe; Steven M Dosick; Steven S Gale; et al Vascular and Endovascular Surgery; Jul/Aug 24; 38,4; Research Library pg. 339 Vascular and Endovascular Surgery Volume 38, Number 4, Fate of Great Saphenous Vein After Radio-Frequency Ablation: Detailed Ultrasound Imaging Sergio X. Salles-Cunha, PhD, RVT, Hiranya Rajasinghe, MD, Steven M. Dosick, MD, Steven S. Gale, MD, RVT, Andrew Seiwert, MD, Linda Jones, RVT, Hugh G. Beebe, MD, and Anthony J. Comerota, MD, RVT, Toledo, OH Radio-frequency ablation (RFA) of the great saphenous vein (GSV) is an endovascular alternative to stripping. To determine long-term effectiveness, the fate of GSV treated for valvular insufficiency with RFA was evaluated in detail with ultrasound imaging (US). One hundred lower extremities were examined with high-resolution color flow US, an average of 8 months after RFA treatment of an incompetent GSV. For every cm of the RFA-treated segment, the US observation was classified as follows: absent, occluded, or recanalized. Lengths of vein segments in each class were added and percentages of absent, occluded, or recanalized segments were calculated. Five groups were identified. Group I (n= 15): segment of treated GSV was absent. Group II (n = 4): segment of treated GSV was visualized and occluded (these vein segments had no flow and were shrunk and "fibrotic" or thrombosed without clear evidence of significant shrinkage). Group ill (n= 1): segment of treated GSV was recanalized. Group IV (n = 27): segment of treated GSV was obstructed (absent or occluded). Group V (n = 53): segment of treated GSV was partially recanalized, on average being 53% absent, 32% occluded, and 15% recanalized. Maximum recanalization was 5% of treated segment, RFA was successful in obliterating all of the GSV treated segment in 46% of veins (groups 1,15%, plus II, 4%, plus IV, 27%) and obliterated more than half of the treated vein segment in 53% of the cases (group V). A dynamic process of recanalization and thrombosis warrants further evaluation to determine if and how a collateral network may develop. Introduction Vase Endovasc Surg 38: , 24 From the Jobst Vascular Center, Toledo, OH Correspondence: Sergio Salles-Cunha, PhD, Jobst Vascular Center, 219 Hughes Drive, Suite 4, Toledo, OH ssallescunha@jvc.org 24 Westminster Publications, Inc., 78 Glen Cove Avenue, Glen Head, NY 11545, USA Endovascular radio-frequency ablation (RFA) is a Food and Drug Administration-approved treatment to eradicate the incompetent great saphenous vein (GSV).1"1 This procedure is designed to replace saphenous vein stripping. Candidates for RFA include patients with symptomatic GSV incompetence. These patients present with telangiectasias, varicose veins, skin pigmentation, and even healed or nonhealed ulcers.11"13 Abla-

2 34 Vascular and Endovascular Surgery Volume 38, Number 4, 24 tion follows exposure of the vein wall to heat created by radio-frequency electric currents. RFA is performed with a catheter pull back from just distal to the saphenofemoral junction in the groin to below-knee. The procedure is performed in an outpatient setting with prompt recovery and has been accepted by patients because of rapid recovery with less morbidity than traditional stripping. Despite apparent success with associated improvement of patients' clinical condition, the fate of the treated segment of CSV remains to be investigated in detail. Reports suggest complete obliteration of the treated segment in all or virtually all cases as determined by duplex ultrasonography,4'6'8'14"18 which was characterized by either thrombosis or vein shrinkage. However, late results indicate the presence of segmental flow, segmental reflux, or complete recanalization in some patients. With the exception of characterizing length of reflux at the proximal segment near the junction, most investigations classified the entire vein as nonvisualized, shmnk, or obliterated. It is possible that a single treated vein may have more than 1 treatment result. This investigation focused, therefore, on the ultrasonographic examination of RFA-treated great saphenous vein in centimeter increments. Color flow, B-mode ultrasound imaging was used to determine if each vein segment was nonvisualized, obstructed (shrunk or thrombosed), or recanalized. Methods Patient Population One hundred extremities of 84 patients were examined. Average follow-up period was 8 months (range 4 to 14 months). Female and male gender represented 82% and 18% of the extremities, respectively. Average age was 54 ±13 years (range 24 to 84 years). Radio-Frequency Ablation All procedures were performed to treat symptomatic valvular insufficiency of the great saphenous vein. Two extremities had ulcers, 15 had healed ulcers, and 23 had skin changes varying from mild (n=15) to severe stasis dermatitis (n = 8). Of these 4 extremities, 31 had additional varicose veins. The remaining 6 extremities had varicose veins associated with mild to severe edema, pain, and/or severe discomfort. Varicose veins were marked immediately before the procedure with the patient standing. After induction of anesthesia, the saphenous vein was cannulated under ultrasound guidance, most commonly below the knee, at mid to upper calf. After placement of a guidewire and a 6 F introducer sheath, a 6 F VNUS RFA catheter was advanced to the saphenofemoral junction. A 6 F catheter was employed in 75% of the cases. Different size guidewires, sheaths, and RFA catheters were used exceptionally. An 8 F or a 5 F catheter was used in 18% and 7% of the cases, respectively. Tumescent anesthesia was employed locally as needed to create a skin-catheter separation greater than 1 cm. With the radio frequency on and the equipment showing stable temperature and resistance, the catheter was pulled back at a rate of approximately 3 cm/minute. Successful ablation of the saphenous vein was confirmed with ultrasound imaging. Because RFA was considered an alternative to stripping only, the vascular surgeons at the Jobst Vascular Center opted for continuing the practice of saphenofemoral junction ligation and division. RFA of the great saphenous vein was followed by ligation and division of the saphenofemoral junction in 87% of the procedures. Microphlebectomies of multiple varicose veins were performed in 91% of the extremities treated. In addition to RFA of the great saphenous vein at the thigh and knee level, stripping of the calf segment was performed in 5 extremities. In 2 instances, a duplicate great saphenous vein in the thigh was stripped. The small saphenous vein was stripped in 4 extremities. Ultrasonography Ultrasound imaging of the treated great saphenous vein was performed with an ATL HDI 5.(Philips Ultrasound, Bothell, WA). A linear-array, 4-7 MHz probe was used, being replaced by a curved-array 2-5 MHz ultrasound probe as needed to image veins in large thighs. The patient was supine on a stretcher inclined 1 to 2, feet down, to fill the veins of the leg. Body and extremity rotation improved exposure of the thigh region available to search for an apparently absent great saphenous vein. A measuring tape was placed anteriorly from groin to foot, with the zero marker at the groin crease. Ultrasound imaging information was obtained at centimeter incre-

3 Salles-Cunha Radio-Frequency Ablation of CSV 341 merits, starting at the common femoral vein and proceeding distally. Image depth, focus, zooming, and color flow sensitivity were optimized. Each centimeter of treated segments of CSV was classified as 1 of 3 outcomes: (1) absent (nonvisualized); (2) occluded (shrunk, atretic, "fibrotic," thrombosed); or (3) recanalized. Figure 1 shows a long, occluded segment of a treated CSV. Figure 2 details shrinkage, thrombosis, and recanalization with reflux. The untreated distal saphenous vein was described as patent (and competent), refluxing, thrombosed, or absent. The length of the segment of CSV treated was determined from the operative report. Absent, occluded, or recanalized centimeter segments were added and the respective sums were expressed as a percentage of the treated segment. Results Five major groups were identified according to various combinations of the 3 outcomes (absence, occlusion, or recanalization) as depicted by ultrasound imaging (Table I) : I. The entire treated segment was absent II. The entire treated segment was occluded (n = 4). III. The entire segment of CSV was patent and refluxing (n = l). IV. The entire segment was obliterated (absent or occluded) (n = 27). On average, 61% of the treated segment was absent and 39% Figure 1. Expanded field of view of a thigh segment of a greater saphenous vein treated with radio-frequency ablation. The segment includes thrombosed valve sinuses and atretic, shrunk segments. Figure 2. Duplex color flow ultrasonography of a great saphenous vein treated with radiofrequency ablation. A. Shrunk segment. B. Thrombosed segment. C and D. Recanalized segment with flow in both directions.

4 342 Vascular and Endovascular Surgery Volume 38, Number 4, 24 Table I. Ultrasonographic findings after radio-frequency ablation of the great saphenous vein. Group Number of Veins Average % of Treated CSV Segment Absent Occluded Recanalized I 15 1 II 4 1 III 1 1* IV V r *An enlarging component of a double system of veins could not be ruled out as an alternative. * Maximum recanalization: 5% of the treated segment. was occluded. Absent and occluded segments were multiple, of variable lengths, and mixed in sequence without an apparent preference for proximal, mid, or distal location. V. The treated segment had combinations of the 3 outcomes (n = 53). On average, a treated segment was 53% absent, 32% occluded, and 15% recanalized. The treated segment with most recanalization was 5% ablated and 5% recanalized. Small, recanalized segments of 2 cm or less were noted in 11 extremities. Some other common findings may have significance in future recanalization, intermittent thrombosis, and/or chronic obstruction. At least half of the treated segment was nonvisualized in 5 extremities. Frequently, valve sinuses were the segments thrombosed (Figure 2B). Small arteries and veins were often visualized near thrombosed segments. Inflow and outflow tributaries and/or branches were noted in association with recanalized segments. These inflow/outflow vessels were identifiable as superficial, muscular, or perforating veins. Two patients reported development of telangiectasias, or "spider veins," following the RFA procedure. In 1 of these patients, a network of small arteries and veins was observed connecting muscle vessels to thrombosed, treated CSV and then proceeding to the telangiectasia (Figure 3). The common femoral vein was patent, without thrombus, in all 1 extremities examined. Discussion RFA can effectively obliterate the great saphenous vein. Complications described initially have been nearly eliminated as experience with the procedure has evolved, and patient satisfaction is high. As a new treatment modality, the results of RFA are being followed up closely, particularly because recurrence of signs and symptoms and of refluxing veins can occur after treatment of the CSV. An optimal technique to evaluate the results of RFA is color-flow, duplex Doppler ultrasonography. We expanded the information available about US follow-up of extremities treated with RFA to include detailed, comprehensive imaging of the treated vein. The effectiveness of RFA to obliterate flow through the great saphenous vein was confirmed. With 1 exception, blood flow was interrupted in all veins. In 1 extremity, a CSV was detected from the groin to the calf. It remained indeterminate whether this finding was the result of failed RFA, complete recanalization, or whether the vein was a secondary vein of an original dual system that dilated with time. The intended means of treatment, vein damage by thermal energy produced by radio-frequency electric currents, with subse-

5 Salles-Cunha Radio-Frequency Ablation of CSV 343 Figure 3. Left: millimetric artery connecting thrombosed great saphenous vein to telangiectasias that developed several months after radio-frequency treatment. Right: Vein draining minimally recanalized, mostly thrombosed, valve sinus of. great saphenous vein after radio-frequency treatment. This small vein was also connected to veins underneath telangiectasias. quent occlusion, shrinkage, and disappearance, was noted. Occlusion was successful in 99% of the cases. Shrinkage was observed in all visualized, obstructed veins. Although complete disappearance was not common, disappearance of at least a segment of treated CSV was noted in 95% of the cases. We concluded, therefore, that UFA permanently interrupted flow through the saphenous vein. The potential for development of a network of small vessels, however, remains. The following discussion avoids the controversial topic of saphenofemoral junction ligation4'19 and focuses on issues related directly to the treatment of the saphenous vein trunk. Apparently, the RFA catheter tips do not touch the vein wall throughout its length. A combination of vein valve sinus enlargement and pullout speed that is not slow enough may leave undamaged segments behind. These segments may thrombose and recanalize. Recanalization is feasible near a branch or tributary that is not destroyed (Figure 3). Thrombosis stimulates an inflammatory reaction with increased vasoactivity that may result in thrombolysis and recanalization.2'21 Some of the thrombus observed did not have the ultrasound appearance of chronic obstruction. Some images were consistent with fresh thrombus, particularly in regions connected to small, recanalizing vessels. This dynamic process of recanalization and thrombosis warrants further evaluation to determine if and how a network of small vessels may develop. Another potential complication associated with small vessels is the onset of telangiectasias. Most red or purple telangiectasias include not only veins but also small arteries. The inflammatory reaction dilates small arteries and veins.2'21 Telangiectasias may, therefore, be a consequence of this increased vascularity expanding to the skin. This complication is not exclusive of the RFA treatment and has been noted following saphenous vein stripping also.22 Most likely, this adverse event is significant only from an aesthetic point of view and can be successfully treated with sclerotherapy. The incidence of significant recanalization in this series was 3 times higher than reported by the multicenter registry9 and more in line with data from Finland.8 Besides population variability, our detailed search with high-sensitivity color flow may have enhanced otherwise undetectable low-flow channels. RFA is intended to act on the vein wall and cause contraction. Vein shrinkage has been observed either immediately after treatment or as a consequence of thrombus fibrosis The shrunken vein should eventually become imperceptible under ultrasound imaging. Complete disappearance of almost all treated veins at 2 years has been reported.6 Our findings were consistent with partial, segmental, but not complete disappearance. Visualized segments may not have shrunk but may have recanalized or may have active thrombus. With longer, detailed follow-up, we

6 344 Vascular and Endovascular Surgery Volume 38, Number 4, 24 should observe if most veins become undetectable by ultrasound or if a network of small vessels forms around unablated CSV segments. In summary, RFA obliterated flow through the great saphenous vein. This vein was expected to thrombose, shrink, and disappear. All veins, with 1 exception, were obstructed over 5% of the treated segment. All but 5 obstructed veins had treated segments that "disappeared," that is, were not visualized. Segmental recanalization, however, was noted and its consequences need to be further investigated. In particular, the relationships among thrombosis, inflammatory reaction, thrombolysis, recanalization, and neovascularization remain to be addressed during longterm follow-up. REFERENCES 1. Manfrini S, Gasbarro V, Danielsson G, et al: Endovenous management of saphenous vein reflux. J Vase Surg 32:33-342, Goldman MP: Closure of the greater saphenous vein with endoluminal radiofrequency thermal heating of the vein wall in combination with ambulatory phlebectomy: Preliminary 6-month follow-up. Dermatol Surg 26: , Chandler JG, Pichot O, Sessa C, et al: Treatment of primary venous insufficiency by endovenous saphenous vein obliteration. Vase Surg 34:21-214, Chandler JG, Pichot O, Sessa C, et al: Defining the role of extended saphenofemoral junction ligation: A prospective comparative study. J Vase Surg 32: , Kabnik LS, Merchant RF: Twelve- and twenty-fourmonth follow-up after endovascular obliteration of saphenous vein reflux: A report from the multicenter registry. J Phlebology 1:17-24, Weiss RA, Weiss MA: Controlled radiofrequency endovenous occlusion using a unique radiofrequency catheter under duplex guidance to eliminate saphenous varicose vein reflux: A 2-year follow-up. Dermatol Surg 28:38-42, Bergan JJ, Kumins NH, Owens EL, et al: Surgical and endovascular treatment of lower extremity venous insufficiency. J Vase Interv Radio! 13: , Rautio TT, Perala JM, Wiik HT, et al: Endovenous obliteration with radiofrequency-resistive heating for greater saphenous vein insufficiency: A feasibility study. J Vase Interv Radio! 13: , Merchant RF, DePalma RG, Kabnick LS: Endovascular obliteration of saphenous reflux: A multicenter study. J Vase Surg 35: , Sybrandy JEM, Wittens CHA: Initial experiences in endovenous treatment of saphenous vein reflux. J Vase Surg 36: , Bergan JJ: Surgical management of primary and recurrent varicose veins. In: Handbook of Venous Disorders. Guidelines of the American Venous Forum, ed. 2, ed. by Gloviczki P, Yao JST. London: Arnold, 21, pp Labropoulos N, Delis K, Nicolaides AN, et al: The role of the distribution and anatomic extent of reflux in the development of signs and symptoms in chronic venous insufficiency. J Vase Surg 23:54-51, Evans CJ, Allan PL, Lee AJ, et al: Prevalence of venous reflux in the general population on duplex scanning: The Edinburg vein study. J Vase Surg 28: , Pichot O, Sessa C, Chandler JG, et al: Role of duplex imaging in endovenous obliteration for primary venous insufficiency. J Endovasc Ther 7: , Fassiadis N, Kianifard B, Holdstock JM, et al: Ultrasound changes at the saphenofemoral junction and in the long saphenous vein during the first year after VNUS closure. Int Angiol 21: , Fassiadis N, Kianifard B, Holdstock JM, et al: A novel approach to the treatment of recurrent varicose veins. Int Angiol 21: , Pichot O, Perrin M: Aspects echographiques de la junction sapheno-femorale apres obliteration de la grande veine saphene par radiofrequence (Closure). Phlebologie 55: , Pichot O, Kabnick LS, Creton D, et al: Duplex ultrasound scan findings 2 years after great saphenous vein radiofrequency endovenous obliteration. J Vase Surg 39: , Rajasinghe H, Salles-Cunha SX, Dosick SM, et al: Patency and reflux findings after greater saphenous vein junction ligation and radio frequency ablation: A duplex ultrasound analysis. Final Program, AVF 15th Annual Meeting, Cancun, Mexico, February 2-23, 23, p Wakefield TW, Stricter RM, Schaub R, et al: Venous thrombosis prophylaxis by inflammatory inhibition without anticoagulation therapy. J Vase Surg 31:39-324, Wakefield TW, Linn MJ, Henke PK, et al: Neovascularization during venous thrombosis organization: A preliminary study. J Vase Surg 3: , Maeso J, Juan J, Escribano J, et al: Comparison of clinical outcome of stripping and CHIVA for treatment of varicose veins in the lower extremities. Ann Vase Surg 15: , 21.