Vascular Complications after Percutaneous Coronary Intervention Following Hemostasis (see full title below)

Vascular Complications after Percutaneous Coronary Intervention Following Hemostasis with the Mynx Vascular Closure Device Versus the AngioSeal Vascular Closure Device

ABSTRACT: We investigated the prevalence of vascular complications after PCI following hemostasis in 190 patients (67% men and 33% women, mean age 64 years) treated with the AngioSeal vascular closure device (St. Jude Medical, Austin, Texas) versus 238 patients (67% men and 33% women, mean age 64 years) treated with the Mynx vascular closure device (AccessClosure, Mountain View, California). Results. Death, myocardial infarction or stroke occurred in none of the 190 patients (0%) treated with the AngioSeal versus none of 238 patients (0%) treated with the Mynx. Major vascular complications occurred in 4 of 190 patients (2.1%) treated with the AngioSeal versus 5 of 238 patients (2.1%) treated with the Mynx (p not significant). Major vascular complications in patients treated with the AngioSeal included removal of a malfunctioning device (1.1%), hemorrhage requiring intervention (0.5%) and hemorrhage with a loss of > 3g Hgb (0.5%). The major vascular complications in patients treated with the Mynx included retroperitoneal bleeding requiring surgical intervention (0.8%), pseudoaneurysm with surgical repair (0.8%) and hemorrhage with a loss of > 3g Hgb (0.4%). These complications were not significantly different between the two vascular closure devices (p = 0.77). Minor complications included hematoma > 5 cm (0.5%, n = 1) within the AngioSeal group, as well as procedure failure requiring > 30 minutes of manual compression after device deployment, which occurred in 7 out of 190 patients (3.7%) treated with the AngioSeal versus 22 of 238 patients with the Mynx (9.2%) (p = 0.033). Conclusions. Major vascular complications after PCI following hemostasis with vascular closure devices occurred in 2.1% of 190 patients treated with the AngioSeal vascular closure device versus 2.1% of 238 patients treated with the Mynx vascular closure device (p not significant). The Mynx vascular closure device appears to have a higher rate of device failure. J INVASIVE CARDIOL 2010;22:175–178 Key words: vascular closure device, Mynx, AngioSeal, hemorrhage, percutaneous coronary intervention, pseudoaneurysm
Vascular closure devices (VCDs) are commonly used in patients undergoing percutaneous coronary intervention (PCI). In most instances, success rates for femoral access hemostasis exceed 90%.^1–3 They have been indicated as a safe alternative to manual compression with a procedure-related mortality of 4 VCDs have been shown to carry significant advantages over the current gold standard of manual compression for achieving homeostasis following percutaneous vascular procedures. In multiple studies, VCDs have been shown to decrease the time to ambulation as well as hospital discharge with improved post-procedure patient comfort when compared to manual compression.^1–3 However, the use of VCDs is not without risks. Complications of VCDs can include minor bleeding with hematoma formation as well as major bleeding such as retroperitoneal hemorrhage, pseudoaneurysm formation, arteriovenous fistulas, thromboembolic events or device malfunction requiring surgical intervention.⁵ With increased use of antithrombin and dual antiplatelet regimens in recent years, the most common complications of bleeding have been noted to be as high as 9% post PCI.^3,5,8 Moreover, the risk of complications can also be dependent on the severity of an individual patient’s procedural risks such as obesity, high arteriotomy site, procedure duration, and bleeding diathesis as well as the different closure mechanisms which are inherent to each type of VCD.^5,8,9 Development of VCDs began in the mid-1990s and the AngioSeal VCD (AngioSeal, St. Jude Medical, St. Paul, Minnesota) was one of the forerunner VCDs for percutaneous arteriotomy closure. Despite numerous upgrades, the AngioSeal VCD has continued to be one of the most widely used VCDs using an anchor-arteriotomy-collagen sandwich to achieve femoral access hemostasis supplemented by the coagulation-inducing properties of its collagen sponge.^6,7 More recently, a new VCD (Mynx, AccessClosure, Mountain View, California) has been developed which uses an extravascular polyethylene glycol sealant that expands several times its original size upon contact with blood and subcutaneous fluids to seal the arteriotomy, and is eventually hydrolyzed. Limited data exist on the safety and efficacy of the Mynx VCD in comparison to more commonly used VCDs. We sought to evaluate vascular complications after PCI with the Mynx VCD versus one of the more common VCDs used at our institution, the AngioSeal VCD.

Methods

From January, 2008 to September, 2008, patients who presented to our institution for diagnostic left-heart catheterization (LHC) and underwent subsequent immediate PCI (including patients with acute coronary syndromes as well as those undergoing elective PCI) were consecutively evaluated in a retrospective manner for concomitant immediate post-PCI use of the Mynx VCD or AngioSeal VCD. Two hundred and thirty-eight patients in the Mynx group and 190 patients in the AngioSeal group met our inclusion and exclusion criteria within these 9 months and were included in this study. All patients underwent LHC and PCI within the same time period via the same operator using standard techniques and using a 6 French (Fr) arterial sheath size. Anticoagulation after sheath insertion was accomplished using intravenous unfractionated heparin to achieve a target activated clotting time (ACT) of 200–300 seconds. All patients were pretreated with 325 mg of aspirin daily and loaded with 600 mg of clopidogrel (300 mg if previously on a daily 75 mg dose of clopidogrel for > 7 days). In patients in whom arterial closure was contemplated, a femoral arteriogram was performed prior to VCD insertion, and placement of either closure device was performed according to standard techniques. Femoral angiographic characteristics of VCD exclusion for all study patients included: 1) arteriotomy site above the inferior epigastric artery, 2) arteriotomy at or below the common femoral bifurcation, 3) common femoral artery of 5 cm, pseudoaneurysms treated with thrombin injection or additional compression and AV fistula not requiring surgical treatment. Device failure was defined as failure to deploy a sealant/collagen plug with conversion to manual compression or a C-clamp, and procedure failure was defined as successful deployment of the sealant/collagen plug with > 30 minutes of manual compression to obtain hemostasis. Descriptive statistics (means and SD of continuous factors, frequency counts and relative frequencies of categorical factors) were computed by closure type (manual, Mynx or AngioSeal) and overall. For comparisons between the Mynx and AngioSeal groups and other categorical or limited ordinal groups, the Fisher’s exact test, as well as the Pearson’s chi-square test, with and without Yates corrections, were evaluated (corrected for continuity in 2 x 2 tables). Analyses of the relationships between the Mynx and AngioSeal characteristics by various groups were performed using multilevel cross-tabulation tables to achieve chi-square values. For all analyses, the criterion for statistical significance was set at p ≤ 0.05, two-tailed.

Results

We investigated the prevalence of vascular complications after PCI following hemostasis in 190 patients (67% men and 33% women, mean age 64 years ± 11 years) treated with the AngioSeal VCD versus 238 patients (67% men and 33% women, mean age 64 years ± 11 years) treated with the Mynx VCD. Review of the baseline characteristics revealed no significant differences between the two groups (Table 1). Death, myocardial infarction or stroke occurred in none of the 190 patients (0%) treated with the AngioSeal VCD versus none of the 238 patients (0%) treated with the Mynx VCD (p not significant). Major vascular complications occurred in 4 of 190 patients (2.1%) treated with the AngioSeal VCD versus 5 of 238 patients (2.1%) treated with the Mynx VCD (p not significant). Major vascular complications in patients treated with the AngioSeal VCD included mechanical device failure requiring surgical removal of the malfunctioning device (1.1%, n = 2), hemorrhage requiring surgical intervention (0.5%, n = 1) and hemorrhage with loss of > 3 g of hemoglobin requiring blood transfusion (0.5%, n = 1). Major vascular complications in patients treated with the Mynx VCD included retroperitoneal bleeding requiring surgical intervention (0.8%, n = 2), pseudoaneurysm requiring surgical repair (0.8%, n = 2) and hemorrhage with loss of > 3 g of hemoglobin requiring blood transfusion (0.4%, n = 1). These complications were not significantly different between the two vascular closure devices (p = 0.77). Minor vascular complications included hematoma > 5 cm (0.5%, n = 1 vs. 0% n = 0; p = NS) within the AngioSeal and Mynx cohorts, respectively. Procedure failure, defined as successful deployment of the sealant/collagen plug with more than 30 minutes of manual compression to obtain hemostasis occurred in 7 out of 190 patients (3.7%) treated with the AngioSeal VCD (average intra-operative heparin dose 3,833 units) versus 22 of 238 patients (9.2%) treated with the Mynx VCD (average intra-operative heparin dose 6,531 units); p = 0.033 (Table 2).

Discussion

VCDs introduce a novel means for improving patient comfort and accelerating ambulation after invasive cardiovascular procedures performed via femoral arterial access. The Mynx VCD is noted to decrease time to hemostasis and ambulation in comparison to manual compression and no use of a VCD. In our study, major vascular complications after PCI following hemostasis with a VCD occurred in 2.1% of 190 patients treated with the AngioSeal VCD versus 2.1% of 238 patients treated with the Mynx VCD (p not significant). The Mynx VCD did have higher rates of procedural failure in maintaining hemostasis. However, it was noted that the Mynx cohort also carried higher risks for bleeding. In a subanalysis of procedural failure patients, the Mynx patients had a higher body mass index (BMI 30 kg/m² for the Mynx VCD vs. a BMI of 24 kg/m² for the AngioSeal VCD; p = 0.11), as well as use of higher doses of intravenous heparin (average heparin dose in the Mynx group 6,500 USP units vs. 3,833 USP units in the AngioSeal group; p = 0.21). Furthermore, our center was an early adopter of the Mynx VCD, and our data includes⁷ the learning curve of initial use of the VCD. Since their inception in the 1990s, there have been several VCDs used at our institution by our interventional cardiologist and fellows including the Perclose VCD (Abbott Vascular, Redwood City, California), the Starclose VCD (Abbott Vascular), the AngioSeal VCD, and more recently, the Mynx VCD. The AngioSeal VCD has been considered to be one of the easier VCDs to master at our institution, with a fairly long track record. Its disadvantage, like other VCDs, is that its use is limited to access sites of 8 Fr or smaller. The collagen anchor of the AngioSeal has been labeled as nonthrombogenic; however, it has been reported to be a nidus for thrombus formation. Furthermore, the interior anchor also limits its utilization in the presence of severe peripheral vascular disease or when the arteriotomy incision is at or below the common femoral artery bifurcation. The Perclose VCD uses an automated suture system for complete tissue apposition and has the potential advantages of leaving only a small amount of stitch within the vessel. Repeat access can be immediate, and it is the only VCD that can accommodate closure of arteriotomy incisions greater than an 8 Fr size sheath. However, with device malfunction, it can result in the need for surgical intervention. The Starclose VCD uses a nitinol clip and has the advantage of being extravascular. The Starclose VCD also has the disadvantage of its use being limited to the use of 8 Fr sheaths or smaller. Other devices have been developed that have their own inherent limitations. However, unlike the more commonly used AngioSeal VCD at our institution, the Mynx sealant is unique in that its polyethylene glycol polymer is delivered to the extravascular surface and is said to be bio-inert and to reabsorb within Study limitations. This study was a retrospective evaluation of patients undergoing two the use of different types of VCDs. Patients needing acute coronary intervention as well as elective PCI were enrolled together. However, the milieu of acute coronary syndromes may present different rates of VCD complications when compared to elective PCI. Our institution generally favors a heparin-based protocol (versus glycoprotein IIb/IIIa inhibitor or bivalirudin use), and VCD complications may differ with such protocols. The AngioSeal VCD has also been a traditionally favored VCD at our institution. That said, our operators generally feel that the Mynx VCD is less discomforting to patients, and when patients raised any concerns about discomfort, the Mynx device was generally used over the AngioSeal VCD, as well as when patients were likely to need reintervention (percutaneous or surgical) within 1 month of original VCD placement.

Conclusion

In conclusion, this single-center study has demonstrated that while procedure failure may be higher with the Mynx VCD, major vascular complications are not significantly higher than the more routinely used AngioSeal VCD. Larger randomized trials allowing broader physician experience with the Mynx are needed to further define the limitations of the Mynx VCD.

References

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2. Baim DS, Knopf WD, Hinohara T, et al. Suture-mediated closure of the femoral access site after cardiac catheterization: Results of the Suture To Ambulate aNd Discharge (STAND I and STAND II) trials. Am J Cardiol 2000;85:864–869.

3. Fram DB, Giri S, Jamil G, et al. Suture closure of the femoral arteriotomy following invasive cardiac procedures: A detailed analysis of efficacy, complications, and the impact of early ambulation in 1,200 consecutive, unselected cases. Catheter Cardiovasc Interv 2001;53:163–173.

4. Duffin DC, Muhlestein JB, Allisson SB, et al. Femoral arterial puncture management after percutaneous coronary procedures: A comparison of clinical outcomes and patient satisfaction between manual compression and two different vascular closure devices. J Invasive Cardiol 2001;13:354–362.

5. Tavris DR, Gallauresi BA, Lin B, et al. Risk of local adverse events following cardiac catheterization by hemostasis device use and gender. J Invasive Cardiol 2004;16:459–464.

6. Behan MW, Large JK, Patel NR, et al. A randomised controlled trial comparing the routine use of an Angio-Seal STS device strategy with conventional femoral haemostasis methods in a district general hospital. Int J Clin Pract 2007;61:367–372.

7. Park Y, Roh HG, Choo SW, et al. Prospective comparison of collagen plug (Angio-Seal) and suture-mediated (the Closer S) closure devices at femoral access sites. Korean J Radiol 2005;6:248–255. 8. Koreny M, Riedmuller E, Nikfardjam M, et al. Arterial puncture closing devices compared with standard manual compression after cardiac catheterization: Systematic review and meta-analysis. JAMA 2004;291:350–357.

9. Dauerman HL, Applegate RJ, Cohen D. Vascular closure devices, The second decade. J Am Coll Cardiol, 2007;50:1617–1626.

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From New York Medical College, Department of Cardiology, Macy Pavilion, Valhalla, New York and UCLA, Department of Cardiology, Los Angeles, California. The authors report no conflicts of interest regarding the content herein. This study was funded internally by NYMC without any outside grant, contracts, or financial support. A scientific session travel stipend for abstract presentation was provided by AccessClosure, Inc. Manuscript submitted November 20, 2009, provisional acceptance given December 2, 2009, final version accepted January 18, 2010. Address for correspondence: Shah Azmoon, MD, New York Medical College, Department Cardiology, Macy Pavilion, 95 Grasslands Road, Valhalla,