Efficacy and Long-Term Safety of StarClose‚Ñ¢ for Hemostasis of Arterial Puncture Sites Distal to Common Femoral Artery Bifurcation After Percutaneous Coronary Interventions

Background. Currently approved vascular closure devices (VCDs) are not recommended for use in arterial puncture sites distal to the common femoral artery (CFA) bifurcation. The StarClose^™ vascular system (SC) is a unique VCD that does not contain intravascular components, a feature that may allow safe use in smaller vessels. Objective. We sought to determine the efficacy and long-term safety of the SC for hemostasis of arterial punctures distal to the CFA bifurcation. Methods. Consecutive patients with arterial puncture sites located distal to the CFA bifurcation received SC after percutaneous coronary intervention (PCI). Patients were ambulated 4–6 hours later, and the presence of vascular complications was determined clinically before hospital discharge. Clinical and Doppler ultrasound examinations were performed at 8–9 months to assess long-term safety.ABSTRACT: Background. Currently approved vascular closure devices (VCDs) are not recommended for use in arterial puncture sites distal to the common femoral artery (CFA) bifurcation. The StarClose^™ vascular system (SC) is a unique VCD that does not contain intravascular components, a feature that may allow safe use in smaller vessels. Objective. We sought to determine the efficacy and long-term safety of the SC for hemostasis of arterial punctures distal to the CFA bifurcation. Methods. Consecutive patients with arterial puncture sites located distal to the CFA bifurcation received SC after percutaneous coronary intervention (PCI). Patients were ambulated 4–6 hours later, and the presence of vascular complications was determined clinically before hospital discharge. Clinical and Doppler ultrasound examinations were performed at 8–9 months to assess long-term safety. Results. A total of 106 patients undergoing PCI were included in the study. Mean age was 66 ± 12 years and 63% were male. The arterial puncture site was located in the superficial femoral artery (SFA) in 76 (72%), the profunda femoris artery (PFA) in 22 (21%) and undetermined in 8 (7%) patients. The mean diameter of the CFA was significantly greater than the SFA or the PFA branch with the SC (6.2 ± 1.5 vs. 4.5 ± 1.0 mm for the CFA and branch with SC, respectively; p Conclusion. The SC can be used for hemostasis after PCI in select cases where the arterial puncture site is located distal to the CFA bifurcation without adverse clinical outcomes. J INVASIVE CARDIOL 2010;22:505–510 Key words: arterial closure, hemostasis, percutaneous coronary intervention ———————————————————— Vascular closure devices (VCDs) are commonly used after interventional procedures to achieve hemostasis and facilitate early patient ambulation.¹ Several VCDs have been approved for clinical use since early 1990s, but only a few have received wider acceptance by endovascular and interventional operators.^1,2 At present, the most commonly used VCDs include AngioSeal^™ (St. Jude Medical, Minnetonka, Minnesota), Perclose^® (Abbott Vascular, Abbott Park, Illinois), StarClose^™ (Abbott Vascular) and Mynx^™ (Access Closure, Inc., Mountain View, California). Currently available devices are indicated for arteriotomy closure after angiographic confirmation of the puncture location in the common femoral artery (CFA) with a diameter ≥ 4 mm.^3,4 However, an aberrant puncture of the superficial femoral artery (SFA) or profunda femoris artery (PFA) distal to the CFA bifurcation is not uncommon in patients undergoing catheterization^5,6 and presents difficulty in management. In this study, we investigated immediate efficacy and long-term safety of the StarClose (SC), a unique VCD that utilizes an extraluminal nitinol clip for hemostasis of arterial puncture sites distal to the CFA bifurcation, which is otherwise not indicated for VCDs.

Methods

Study population. All patients undergoing percutaneous coronary intervention (PCI) with a planned VCD for access-site hemostasis underwent selective femoral angiography. Consecutive patients with an arterial puncture distal to the CFA bifurcation were treated with a SC device for hemostasis. No patients with an arteriotomy location distal to the CFA bifurcation were excluded from SC placement during the study period except for patients with symptomatic peripheral arterial disease and > 6 Fr sheath placement to avoid selection bias. All patients were enrolled in a registry and clinical outcomes were prospectively collected. Patients were ambulated 4–6 hours post procedure after successful groin hemostasis had been achieved. Adequacy of groin hemostasis and quantitative assessment of hematoma size, if present, were determined every 6 hours by trained nurses using a wound measuring tool (Briggs^® MediRule II). Bleeding was assessed by comparison of hemoglobin values prior to and 24 hours following SC placement. All patients were examined by a physician for the presence of vascular complications at 24 hours after SC placement or before hospital discharge. Quantitative angiographic analysis of the CFA and its branches was performed by physicians blinded to the procedure details or study endpoints. All patients underwent clinical follow up, focused examination and Doppler ultrasound of the access site 8–9 months after SC placement for assessment of arterial insufficiency and vascular complication. StarClose vascular system (SC) and deployment technique. The SC is designed to close 5 Fr and 6 Fr arterial punctures following percutaneous invasive procedures and delivers a 4-mm diameter, 0.008-inch thick nitinol clip on the extravascular surface of the arteriotomy site. The clip holds the perivascular tissue in a circumferential manner and maintains secure apposition of the arteriotomy edges without leftover intravascular components. To facilitate SC deployment post procedure, the cutaneous entry site and subcutaneous track in the groin area were infiltrated with local anesthetic and dilated along the sheath with a hemostat. Following exchange of the procedural sheath for a SC exchange sheath, the clip applier on the SC was advanced through the sheath and locked in the alignment notch. The vessel locator button on the SC was pushed to advance the vessel locator in the CFA. The clip applier was pulled back until the vessel locator wings met resistance, indicating apposition to the anterior vessel wall. Close attention was paid during SC retraction to prevent catching of the vessel locator wings at the CFA bifurcation and a gentle wiggle motion was used, if necessary, to facilitate SC movement until the vessel locator wings met the anterior vessel wall. The thumb advancer on the clip applier was moved forward to split the exchange sheath and advance the clip delivery tube for positioning of the nitinol clip at the arteriotomy site. The clip applier was moved perpendicularly to the long axis of the femoral artery. The nitinol clip was deployed by pressing the trigger button with slight downward pressure on the clip applier to assist capture of the vascular adventitia by the nitinol clip. The SC tissue tract and subcutaneous tissue were infiltrated with 10–20 ml of premixed Xylocaine^® (1% lidocaine hydrochloride and 1:100,000 epinephrine, Astra Zeneca Canada, Inc., Mississauga, Ontario) and manual compression of ≤ 5 minutes was applied, if needed, to assist access-site hemostasis after SC placement. All SC device placements were performed by operators proficient in SC use. Definitions. Device success was defined as adequate hemostasis achieved in the catheterization laboratory without major vascular complications as reported previously.⁷Access-site vascular bleeding was defined according to the ACUITY criteria.⁸Procedural success was defined as residual stenosis of Major adverse vascular events (MAVE) were defined as the presence of one or more events including a hemoglobin drop ≥ 3 g/dl or bleeding requiring blood transfusion; groin hematoma ≥ 5 cm; clinical evidence of pseudoaneurysm; arteriovenous fistula; local infection requiring oral or intravenous antibiotics; symptomatic nerve damage; symptomatic lower extremity ischemia; and need for arterial repair during the first 24 hours after SC placement. Long-term adverse vascular events were defined as symptoms of arterial insufficiency in the SC-treated lower extremity or presence of a pseudoaneurysm, arteriovenous fistula and asymptomatic arterial stenosis ≥ 50% in the CFA branch with SC on Doppler ultrasound follow up. Quantitative angiography. Angiographic images of the CFA were acquired by contrast injection through the side arm of the arterial sheath in a 40° right or left anterior oblique projection with centering of the arterial puncture site. Additional angiographic images were obtained for delineation of the arterial puncture at the discretion of the operating physician. All femoral angiograms were analyzed for quantitative analysis using automatic edge-detection software (Medis Medical Imaging Systems, Leiden, Netherlands) by physicians blinded to the study endpoints. Measurements were calculated for the diameter of the CFA, SFA and PFA. The degree of calcification in the CFA, SFA, and PFA was determined in a semiquantitative manner on cine images of contrast-free arterial lumens by offline analysis. The calcification assessment was performed in the area of interest that included 6 cm above and 12 cm below the center of the femoral head. The degree of calcification was classified as none if no plaques were seen, mild if sporadic plaques were seen in any wall, moderate if dense continuous plaque was present in at least one wall and severe if dense plaques were present in both walls of either the CFA, SFA or PFA, identifying the location of the artery without contrast for any arterial segment at the specified location. Doppler ultrasound examination. Doppler ultrasound of the CFA, SFA and PFA was performed by an experienced technologist at a dedicated vascular laboratory with a L9-3, a 9-3 MHz linear probe on a Philips iU22 ultrasound machine (Philips Medical, Andover, Massachusetts) 8–9 months after SC placement. The scanned area included 6 cm superior and 12 cm inferior to the inguinal ligament and included 2-dimensional grayscale, color-enhanced and spectral Doppler flow measurements according to a previously published protocol.⁹ Briefly, qualitative assessment was performed to determine the presence of a pseudoaneurysm, arteriovenous fistula, arterial or venous thrombosis and arterial stenosis. Pulsed Doppler evaluation was performed using a small sample volume placed in the center stream and Doppler signals collected in the mid and distal CFA, SFA and PFA. Abnormally elevated peak systolic flow velocity suggesting > 50% arterial stenosis in an arterial segment was defined as a ≥ 100% increase in peak systolic flow velocity compared to the proximal normal segment. All studies were analyzed by observers blinded to procedure details, presence or location of the SC device and immediate or long-term clinical events. Statistical analysis. Descriptive statistics (means, standard deviations, medians, ranges, proportions) and graphs (histograms, bar charts) were used for initial analysis. The student’s t-test for paired samples was used to compare the diameter of the CFA and its branch with SC. All analyses were performed using SPSS software (SPSS, Inc., Chicago, Illinois). A p-value ≤ 0.05 was considered statistically significant.

Results

A total of 106 patients were included in the study over a 26-month period (November 2006 to January 2009) and represented 12% of all patients undergoing coronary intervention by the study operators (Figure 1). Baseline clinical and procedural characteristics are summarized in Table 1. Mean age was 66 ± 12 years and 67 (63%) patients were male. Coronary stenting was performed in 103 (97%), and 93 (88%) received adjunctive glycoprotein IIb/IIIa platelet receptor antagonist or bivalirudin therapy. The angiographic results are outlined in Table 2. The arterial puncture was located in the SFA in 76 (72%), PFA in 22 (21%) and undetermined in 8 (7%) patients due to angiographic limitations or close proximity of the arterial puncture to the CFA bifurcation. The mean diameter of the CFA was significantly greater than its distal branch with SC placement (6.2 ± 1.5 vs. 4.5 ± 1.0 mm for the CFA and SC branch, respectively; p In-hospital outcomes. Procedural success was achieved in 104 (98%) patients. The device success was seen in 100 (94%) patients. Among 6 patients with device failure, no hemostasis occurred in 2 patients, and incomplete immediate hemostasis was present in 4 patients. These patients were managed by application of the FemoStop device (RADI Medical Systems, Uppsala, Sweden) or prolonged manual compression. Heparin reversal with protamine administration was used in 4 patients. Periprocedural myocardial infarction occurred in 11 (10%) patients. At 24 hours, a hematoma ≥ 5 cm was reported in 13 (12%) patients. No other MAVE including access-site bleeding, clinical evidence of a pseudoaneurysm, arteriovenous fistula, local infection and neurological or vascular injury were observed. Long-term follow up. At a mean follow up of 9 ± 2.5 months, 100 (94%) patients were seen in the outpatient clinic, 3 patients were interviewed on the phone and 3 patients had died. One patient presented with definite stent thrombosis 6 days after stenting and underwent primary angioplasty with repeat arterial puncture at the previous SC site. He was mechanically ventilated and supported with an intra-aortic balloon pump in the intensive care unit post procedure. He developed infection of the SC groin puncture site 3 days after his second interventional procedure (9 days after SC placement) followed by staphylococcal septicemia with septic emboli requiring intravenous antibiotics, surgical debridement and removal of the infected SC device. He recovered after a prolonged stay in the intensive care unit, but experienced sudden cardiac death 2 months later in a convalescent setting. One patient died 5 months later after being hospitalized for recurrent myocardial infarction and cardiogenic shock. One death was non-cardiac-related in a patient with end-stage renal disease. All patients seen in the clinic had remained asymptomatic with normal femoral, dorsalis pedis and posterior tibial pulses in the lower extremity with SC placement. Doppler ultrasound of the SC site on follow up was completed in 100 (94%) patients (Figures 2 and 3) and results are shown in Table 3. Three patients had died and another 3 patients refused ultrasound follow up. All patients with Doppler ultrasound demonstrated patency of the CFA, SFA and PFA, with no instance of arterial or venous thrombosis or stenosis. Soft-tissue reaction to the SC evidenced by periarterial inflammation was not observed on any examination. The SC nitinol clip, seen as a bright echogenic image superficial to the arterial lumen, could be identified in 30 (28%) patients. There was no evidence of pseudoaneurysm, arteriovenous fistula or abnormal blood flow in the CFA, SFA or PFA in any patient.

Discussion

The main finding of the present study is that SC can be successfully used for arterial puncture sites located distal to the CFA bifurcation and results in adequate hemostasis without long-term adverse effects on arterial morphology and function. To our knowledge, this is the first study to report on immediate efficacy and long-term safety of any VCD for arterial punctures distal to the CFA bifurcation. Arterial puncture of the CFA compared to the SFA or PFA is associated with a reduced risk of vascular complications after coronary invasive procedures.^10–12 Furthermore, access of the arterial segment between the CFA bifurcation and the origin of the inferior epigastric artery is best suited for VCD placement.^1,13 However, inadvertent arterial puncture of the SFA and PFA is not uncommon due to a low femoral artery puncture¹⁴ (Figure 2), or a high anatomic CFA bifurcation (Figure 3). The management of an arterial puncture distal to the CFA bifurcation in patients undergoing coronary intervention is challenging due to periprocedural anticoagulation and lack of evidence for VCD use in this setting. Among the currently approved VCDs, AngioSeal has an intravascular anchor that can pose a risk for lumen compromise in small vessels.^15,16 The potential mechanisms of this lumen compromise may include mechanical obstruction by the anchor, intraluminal tissue growth at the deployment site, distal migration of the anchor or thrombosis from intra-arterial placement of the collagen plug. Similarly, Perclose uses intravascular sutures to tie a knot for arteriotomy closure and also carries the potential for compromising the arterial lumen in small vessels.¹⁷ In view of these concerns, both AngioSeal and Perclose are not routinely used for arterial puncture of CFAs with a diameter ≤ 4 mm and no reports have been described regarding the successful use of VCDs for an arterial puncture site below the CFA bifurcation. SC is a novel VCD that uses an extravascular clip without intravascular components. Use of SC for closure of femoral artery punctures after catheterization procedures has shown to be effective and safe compared to manual compression and other arterial closure methods.^7,18,19 Although initial studies of SC excluded patients with arterial puncture of the CFA measuring ≤ 5 mm or distal to the CFA bifurcation,⁷ these unique features may allow its safe use in small-caliber vessels. In addition, SC may be associated with less injury and inflammation of the vessel wall compared to other VCDs.²⁰ Gray et al²¹ recently reported the successful use of SC in atherosclerotic CFAs in patients undergoing percutaneous intervention for peripheral arterial disease. However, increased peak systolic flow velocity in the CFA suggestive of restenosis or progression of atherosclerosis was reported in 4.2% of patients during follow up, all except one of whom were asymptomatic.²¹ Similarly, Noory et al²² successfully used the SC device to close popliteal artery punctures in 28 patients undergoing retrograde recanalization of the SFA. One patient experienced popliteal artery occlusion requiring urgent intervention and 11% of patients developed small hematomas. No long-term follow up was reported for these patients. In comparison, no restenosis of the CFA or its major branches was observed in the present study, a finding likely related to the absence of clinical and angiographic evidence of femoral artery atherosclerosis in study subjects. Puggioni et al²³ also reported the successful use of the SC device for arteriotomy closure of the brachial artery without long-term adverse outcomes in a small number of patients, findings consistent with the present study. The device success rate in the present study was 94%, which is similar to SC use in the CFA as reported by Iman et al¹⁸ (96%) and in the CLIP study⁷ (87%). A hematoma > 5 cm was seen in 12% of patients in this study, which is higher than the 4.3% rate reported previously for the CLIP study,⁷ but is comparable to hematoma rates of SC placement reported in the popliteal²² (11%), the brachial²³ (7%) and the CFA^18,24,25 (8–14%). With the exception of the CLIP study, other studies were performed in patients undergoing diagnostic coronary angiography^21,24 or peripheral intervention^18,22,25 in a patient population not at significant risk for bleeding. In contrast, patients in this study were at high risk of bleeding complications due to the presence of acute coronary syndrome in 44% and administration of glycoprotein IIb/IIIa platelet receptor or direct thrombin inhibitors in 88% of patients, which was much higher than the 30% rate in the CLIP study.⁷ On the contrary, limiting sheath size to 6 Fr, use of premixed lidocaine after SC placement and mandatory bedrest of 4–6 hours post PCI may have reduced the hematoma rates in the present study. There was one major complication in a patient who developed an infection of the arteriotomy site that was complicated by sepsis and required surgical debridement and removal of the SC device. However, this complication was seen 9 days after SC placement and was likely related to tissue tract contamination during repeat arterial access in the ipsilateral groin for emergent coronary intervention and prolonged intensive care unit stay in a patient with several comorbidities. Although use of ultrasound has been suggested to guide SC placement and reduce the risk of vascular complications,²⁶ we were able to successfully deploy the SC device by tactile feedback in all patients. The present study demonstrated no adverse effect on arterial morphology and function on long-term clinical and ultrasound follow up, extending the observations of Jaff et al⁹ who previously reported the absence of vascular complications 30 days post SC deployment by Doppler ultrasound. In addition to the three VCDs discussed earlier, Mynx is another recently approved VCD that uses an extra-arterial vascular closure technology.²⁷ Mynx uses a water-soluble polyethylene glycol matrix that seals the arteriotomy by absorbing subcutaneous fluids and expanding in the tissue tract to achieve hemostasis in the extravascular space. It uses an inflatable balloon to locate the anterior vessel wall and polyethylene glycol sealant is released above the puncture site in the tissue tract. The balloon is deflated and removed without leaving any intraluminal components. Because safety and efficacy of Mynx were demonstrated for hemostasis of CFA puncture sites after percutaneous coronary diagnostic and interventional procedures in a randomized study,²⁷ it may be applicable for hemostasis of small-caliber vessels such as the SFA. However, a recent study suggests that Mynx might be associated with high rates of device failure compared to other VCDs,²⁸ and no data are available regarding its application for arterial puncture sites distal to the CFA bifurcation. Study limitations. The major limitation of the present study is the lack of randomized design and relatively small number of study patients. However, the main objective of this study was to investigate the safety and efficacy of the SC device for arteriotomy closure when other VCDs could not be used and assessment of the long-term effects of SC in small-caliber vessels. A large randomized study is needed to confirm the present findings and compare SC use distal to the CFA bifurcation with other approaches of arterial access-site hemostasis.

Conclusion

The present study suggests that the StarClose Vascular System can be used for hemostasis after PCI in select cases when the arterial puncture site is located distal to the CFA bifurcation without adverse clinical outcomes.

References

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———————————————————— From the ^*Terrence Donnelly Heart Center, the ^§Department of Radiology, and ^£Li Ka Shing Knowledge Institute, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada. The authors report no conflicts of interest regarding the content herein. Manuscript submitted June 8, 2010, provisional acceptance given June 29, 2010, final version accepted August 9, 2010. Address for correspondence: Asim N. Cheema, MD, PhD, Division of Cardiology, St. Michael’s Hospital, 30 Bond Street, Toronto, Ontario, Canada M5B 1W8. E-mail: cheemaa@smh.toronto.on.ca