Prospective randomized trial of ACUSEAL (Gore-Tex) versus Hemashield-Finesse patching during carotid endarterectomy: Early results

Patient population and methods 

Between August, 2003 and October, 2005, 200 carotid endarterectomies (200 patients) were randomized into two groups using either the ACUSEAL polytetrafluoroethylene (PTFE) patching (W. L. Gore & Associates, Flagstaff, Ariz) or the Finesse collagen-impregnated Dacron patching (Boston Scientific Corp, Natick, Mass). Using sealed opaque envelopes, each containing a slip of paper with the patch assignment, patients were randomized in a 1:1 ratio. The randomization envelopes were generated in blocks of 10 and placed in closed containers. After induction of anesthesia, but prior to skin incision, an envelope was pulled from the container by the study controller and opened, and the surgeon was notified of the patch selection. This study was approved by the Institutional Review Board of Charleston Area Medical Center, Robert C. Byrd Health Sciences Center of West Virginia University. Patients excluded from this study included those undergoing CEA with concomitant coronary artery bypass grafting (three patients), and redo CEA (two patients).

Prior to CEA, all patients underwent carotid color duplex ultrasound imaging and/or magnetic resonance angiography as a means of determining preoperative stenosis levels. Baseline blood cholesterol and triglyceride levels were also tested. Preoperative risk factors including hypertension, tobacco use status, diabetes mellitus, coronary artery disease, and any preoperative use of antiplatelet therapy were recorded. Indications for surgery were categorized into hemispheric transient ischemic attacks (TIA), amaurosis fugax, hemispheric strokes, nonhemispheric TIAs, and asymptomatic carotid stenoses of ≥70%.

Results 

Indications for surgery, demographic, and clinical characteristics were comparable between the patch groups (Table I). Table II summarizes the perioperative data for both patches. As shown, the mean internal carotid artery diameter and the length of arteriotomy were comparable for both groups. The hemostasis time was significantly longer for the ACUSEAL patch (5.17 vs 3.73 minutes, P = .01), however, the operative time from skin to skin was comparable for the two patches (97 vs 96 minutes, P = .61). No patients in either group suffered postoperative hematoma requiring exploration.

Table I. Demographic and preoperative data by patch

		ACCUSEAL	Finesse	P-Value
	Number of CEA (N)	100	100
	Female	53	48
	Male	47	52	0.48
	Age (years)	67.7±11.1	68.1±10.1	0.80
	Hypertension	91	86	0.27
	Coronary artery disease	46	43	0.67
	Diabetes mellitus	31	26	0.43
	Peripheral vascular disease	12	14	0.67
	Hyperlipidemia	68	61	0.30
	Current tobacco use	30	35	0.45
	Past tobacco use	40	35	0.47
	Any preop antiplatelet Rx	80	79	0.86
	Preoperative aspirin	66	72	0.36
	Preoperative clopidogrel	37	35	0.77
	Preoperative total cholesterol	179.9±40.5	187.8±37.7	0.15
	Preoperative triglycerides	223.2±153.8	223.0±169.7	0.99
	Indications for CEA			0.78
	Asymptomatic	45(45.0)	45(45.0)	1.0
	Amaurosis fugax and/or hemispheric TIA	41(41.0)	36(36.0)	0.56
	Stroke	8(8.0)	11(11.0)	0.63
	Nonhemispheric TIA	6(6.0)	8(8.0)	0.78

Significance testing by either χ2, Fisher exact, or two-tailed t-tests (with F-tests for variance).

Table II. Perioperative data by patch

		ACCUSEAL	Finesse	P-Value
	Number of CEA (N)	100	100
	Left side CEA	54	53
	Right side CEA	46	47	0.89
	Stenosis of operated vessel			0.30
	50%-59%	6	3	0.50
	60%-69%	16	24	0.22
	70%-99%	78	73	0.51
	ICA diameter (mm)	5.3±0.8	5.5±1.0	0.35
	Arteriotomy length (cm)	4.4±0.8	4.5±0.8	0.35
	Skin to skin operative time (mins)	97.4±23.7	95.9±18.7	0.61
	Hemostasis time (mins)	5.17±5.2	3.73±2.7	0.01

Significance testing by either χ2, Fisher exact, or two-tailed t-tests (with F-tests for variance).

Table III summarizes perioperative morbidity and mortality for both patches. As noted, the perioperative ipsilateral stroke rate was 2% in both patches. The overall perioperative neurologic event (TIA/stroke) rate was 2% for the ACUSEAL patches vs 4% for Finesse patches, however, this difference was not significant (P =.68). There was one perioperative death in the ACUSEAL patch group, which was the same patient who suffered a stroke, whereas the Finesse patch had 0% perioperative mortality. In the two patients with ACUSEAL patching who suffered perioperative strokes, one was discovered in the operating room, and the other occurred on postoperative day three. The patient who had a neurologic deficit in the operating room underwent immediate intraoperative angiogram, followed by exploration with thrombectomy to remove what was felt to be white clots and was repatched. The patient recovered from her stroke in less than 1 week and had a normal duplex exam at 30 days. The other patient had a normal postoperative duplex ultrasound exam without residual stenosis, but suffered an embolic stroke that was treated with heparin therapy, which led to a cerebral hemorrhage and death, 3 days postoperatively.

Table III. Morbidity and mortality data by patch

		ACCUSEAL	Finesse	P-Value
	Number of CEA (N)	100	100
	Any perioperative neurological event	2	4	0.68
	Stroke (ipsilateral)	2	2	1.0
	TIA (ipsilateral)	0	2	0.5
	Perioperative mortality	1⁎	0	1.00
	Restenosis (≥50%) at 30-day U/S	0	4	0.12
	50%-59%	0	1	1.0
	60%-69%	0	0	1.0
	70%-99%	0	1	1.0
	Thrombosis	0	2	0.5
	Combined perioperative neurological events (TIA/stroke, ≥50% restenosis, or carotid thrombosis)†	2	8	0.1

⁎ Patient is 1 of 2 with perioperative stroke. Significance testing by either χ2, Fisher exact or two-tailed t-tests (with F-tests for variance). † Number of patients.

Two patients with Finesse patching had perioperative minor strokes, one was noted in the recovery room and one in the operating room. Both patients had normal postoperative carotid duplex ultrasounds and were treated with antiplatelet therapy. Two other patients with Finesse patching had perioperative TIAs, one was noted in the recovery room and had a normal carotid duplex ultrasound and was treated with antiplatelet therapy; the other patient had a TIA 2 weeks postoperatively with a normal carotid duplex ultrasound and was also treated with antiplatelet therapy.

There were two patients in each group (n = 4 total) with residual stenosis of <50%, all of whom were asymptomatic. The incidence of ≥50% restenosis at 30 days was 0% for the ACUSEAL patch vs 4% for the Finesse patch (this included one patient with asymptomatic 50% to less than 60% stenosis, one patient with asymptomatic 70% to less than 99% stenosis, and two with asymptomatic perioperative carotid thrombosis, P = .5, and both were noted at 30 days postoperatively).

The combined incidence of perioperative neurological events (TIA/stroke) and ≥50% restenosis or carotid thrombosis was 2% for the ACUSEAL patch vs 8% for the Finesse patch (P = .10).

Discussion 

Recently, a systematic review of randomized controlled trials comparing primary closure vs patching,6 concluded that patch angioplasty decreases the risk of perioperative death or stroke as well as long-term risk of ipsilateral ischemic events. Despite this conclusion that routine patching should be recommended based on literature support, the use of autologous vs prosthetic patching was unsettled. Autologous tissue either by jugular vein or saphenous vein, has shown good results.1, 7 However, most institutions use a synthetic patch for multiple reasons such as: eliminating wound-related complications secondary to autologous vein harvesting, leaving vein conduits intact and readily available for potential future coronary or peripheral revascularizations, and reduced incidence of patch rupture and aneurysmal changes.8, 9 Although infection of a carotid patch is a feared complication, we did not see any patch infections in this series.

Bleeding has been the Achilles heel of the PTFE patch. In our previous comparison of conventional PTFE with Hemashield, bleeding was significantly longer with a mean hemostasis time of 14 minutes for PTFE compared with 3 minutes with the Hemashield patch.2 Hemostasis time in the current series with the improved PTFE ACUSEAL patch was 5 minutes, which was similar to the 3 minute time reported in our recent report with this patch.4 Despite this improved hemostasis time compared with the traditional PTFE patch, the Finesse patch had a shorter hemostasis time with a mean of three minutes, although most would consider such a time difference clinically insignificant.

A criticism of our previous randomized study comparing the conventional PTFE to the Hemashield was that we used a PTFE suture (TT-9 needle, CV-6 suture) in the PTFE group only.2 Hence, in the current series we used 6-0 Prolene sutures in both groups. The use of the PTFE suture has been shown to reduce needle hole bleeding in modified PTFE patch with a design of needle/suture diameter ratio of 1:1.10, 11

Overall comparison of perioperative neurological events between the two patches did not demonstrate any statistically significant differences. The overall neurological event rate of the new modified PTFE patch was similar to that found with conventional PTFE reported in our previous randomized trial. (2% vs 3%, respectively). However, the Finesse patch produced better results than those previously achieved with the conventional Hemashield patch (4% vs 12% respectively). Additionally, the number of patients with >50% stenosis at 30-day duplex exam was reduced from 12% in the previous series to 4% using the Finesse patch. The ACUSEAL PTFE patch was comparable to the conventional PTFE for restenosis, with no patients with duplex findings of >50% stenosis at 30 days in the current series compared with our previous report of 2%.12

One concern with the use of the conventional Dacron-Hemashield patches was the thrombogenic nature of this patch, as five perioperative carotid thromboses occurred in our previous experience. The Finesse patch was associated with two perioperative carotid thromboses, compared with none in the ACUSEAL patch group. However, this difference was not statistically significant. Long-term follow-up will be needed to evaluate any potential differences in the rate of late restenosis and thrombosis between the two patches.

Overall, the results of this study show equally good outcomes from both patches. There was no statistically significant difference in deaths, stroke rates, TIA rates, or in early restenosis. Although a significant difference did appear in the hemostatic time, it is probably a finding of limited clinical significance.

Author contributions