***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: PURPOSE This study examines the long-term results of a r and omized prospect i ve study comparing primary versus saphenous vein patch ( VP ) closure after  carotid endarterectomy ( CEA ) .  METHODS One-hundred thirty-six patients undergoing 163 CEAs over a 46-month period were prospect ively r and omized to VP , or primary closure .  Patients with internal carotid artery diameters less than 5 mm and those requiring complex CEAs underwent obligatory vein patch ( OVP ) . Patients were monitored with duplex scanning every 3 months for 1 year and every 6 months thereafter . All patients received aspirin . RESULTS There were three perioperative strokes ( one in the primary group , two in the OVP group ) and no perioperative deaths . Two perioperative revisions were performed within 30 days of the original CEA for residual disease . During a mean follow-up of 59 + /- 4 months , nine ipsilateral neurologic events have occurred , including two strokes and seven transient ischemic attacks . Sixteen patients had duplex evidence of recurrent stenosis , and one was associated with a stroke 36 months after CEA . Recurrence rates were similar in all groups ( cumulative recurrence at 5 years : primary 7.8 % , VP 14.3 % , OVP 5.3 % ) . Of the 136 patients ( 163 procedures ) , 72 ( 53 % ) ( 88 procedures ) are alive and well , 16 ( 11.7 % ) ( 19 procedures ) have been lost to follow-up , and 48 patients ( 35.3 % ) ( 56 procedures ) have died . The cumulative stroke-free survival rate at 84 months was 71 % for VP , 74 % for OVP , and 60 % for the primary group . CONCLUSIONS These results demonstrate that CEA is a durable procedure . The use of VP closure did not produce superior long-term results compared with the use of primary closure in this select group of patients PURPOSE This study examines the long-term clinical outcome and the incidence of recurrent stenosis ( > or = 50 % ) after carotid endarterectomy ( CEA ) with primary closure ( PC ) versus vein patch closure ( VPC ) , saphenous ( SVP ) , and jugular vein ( JVP ) and polytetrafluoroethylene patch closure ( PTFE-P ) . METHODS A total of 399 CEAs were r and omized into the following groups : 135 PC , 134 PTFE-P , and 130 VPC ( SVP alternating with JVP ) .  Postoperative duplex ultrasound scans were performed at 1 , 6 , and 12 months and every year thereafter . The mean follow-up was 30 months with a range of 1 to 62 months , and demographic characteristics were similar in all groups . Kaplan-Meier analysis was used to estimate the risk of restenosis and the stroke-free survival . RESULTS The incidence of ipsilateral stroke was 5 % ( seven of 135 ) for PC , 1 % ( one of 134 ) for PTFE-P , and 0 % for VPC ( PC vs VPC , p = 0.008 ; PC vs PTFE-P , p = 0.034 ) . Seven strokes occurred in the perioperative period . All three groups had similar mortality rates . The cumulative stroke-free survival rate at 48 months was 82 % for PC , 84 % for PTFE-P , and 88 % for VPC ( p < 0.01 for PC vs PTFE-P or VPC ) . PC had a higher incidence of recurrent stenosis and occlusion ( 34 % ) than PTFE-P ( 2 % ) and VPC ( 9 % ) ( SVP 9 % , JVP 8 % ) ( p < 0.001 ) . PTFE-P had a lower recurrent stenosis rate than VPC ( p < 0.045 ) . Restenoses necessitating a redo CEA were also higher for PC ( 11 % ) than for PTFE-P ( 1 % ) and VPC ( 2 % ) ( p < 0.001 ) . Women with PC  had a higher recurrent stenosis rate than men ( 46 % vs 23 % , p = 0.008 ) . Kaplan-Meier analysis showed that freedom from recurrent stenosis at 48 months was 47 % for PC , 84 % for VPC , and 96 % for PTFE-P ( p < 0.001 ) . The SVP and JVP results were comparable . The mean operative diameter of the internal carotid artery was similar in patients with or without restenosis . Significantly more late internal carotid artery dilatations occurred in the VPC group compared with the PC group . CONCLUSIONS Patch closure ( VPC or PTFE-P ) is less likely than PC to cause perioperative stroke . Patching was also superior in lowering the incidence of late recurrent stenoses , especially in women OBJECTIVES Routine patch angioplasty has been advocated following carotid endarterectomy but patching can be associated with complications . This study assesses the effect of a selective patching policy based on distal internal carotid diameter on the rate of restenosis and outcome following carotid endarterectomy . DESIGN , MATERIAL AND METHODS A consecutive series of 213 patients underwent carotid endarterectomy performed by one surgeon . Preoperative carotid dimensions were measured intraoperatively using calipers . Following endarterectomy a 5 mm Dacron patch was selectively employed if the distal internal carotid was 5 mm or less ( group 1 , 95 patients ) or 6 mm or less ( group 2 , 118 patients ) . Patients underwent colour-coded Duplex scanning at 24 h , 1 week , 3 , 6 , 9 , and 12 months , and yearly following this . RESULTS Overall 27 restenoses ( 5 residual ) of 50 % or greater and two occlusions developed .  Patching was performed in 47 % of group 1 and 61 % of group 2 arteries . In group 1 14 % of patched compared with 24 % of non-patched arteries developed restenosis at 24 months ( p=0.4 ) . In group 2 13 % of patched compared to 11 % of non-patched arteries developed restenosis at 12 months ( p>0.5 ) . Stroke rate at 24 months were similar for patched and non-patched patients in groups 1 ( p>0.5 ) and 2 ( p=0.4 ) . CONCLUSIONS This study suggests that patch angioplasty of larger carotid arteries may be unnecessary . R and omisation of larger arteries between patch and primary closure would be required to confirm this A prospect i ve study with r and om selection between primary closure and saphenous vein patching  after carotid endarterectomy was conducted . Patients were evaluated with intravenous digital subtraction angiography during the initial postoperative period , followed by duplex scanning at 3 and 6 months , and then yearly examinations . The series consisted of 129 carotid endarterectomies , of which 62 were primary closures and 67 were patch procedures .  Both groups were identical with regard to risk factors , symptoms , and postoperative control digital subtraction angiography . Restenosis was defined as a stenosis with ≥50 % diameter reduction , as assessed by duplex scanning . Of special interest was the development of restenosis along with the occurrence of cerebrovascular symptoms at long-term follow-up . The follow-up data from the 129 carotid endarterectomies are presented in a life-table analysis . The mean length of follow-up was 5 years ( range 1 to 96 months ) . During the follow-up period 38 patients who had undergone 39 operations died  ( mortality rate 30 % ) ; three deaths were attributed to cerebral causes ( two in-hospital deaths due to intracerebral hemorrhage and one cerebral hemorrhage after 6 months ) . Restenosis occurred in 25 cases ( 19 % ) . This restenosis was detected in 5 of 45 men with primary closure ( 11 % ) , 12 of 17 women with primary closure ( 70 % ) , 7 of 49 men with patch closure ( 14 % ) , and 1 of 18 women with patch closure ( 5.5 % ) . The difference between patch and primary closures was found to be statistically significant ( hazard ratio 0.39 ; 95 % confidence interval 0.17 to 0.91;p=0.03 ) . There was no statistical difference in men who had patch and primary closures ( hazard ratio 1.23 ; 95 % confidence interval 0.39 to 3.87;p=0.73 ) , but there was a statistically significant difference in women who had patch and primary closures ( hazard ratio 0.059 ; 95 % confidence interval 0.0076 to 0.45;p=0.007 ) . The hazard ratios in men and women differed significantly ( p=0.014 ) . Late restenoses were seen in all patient groups , patched and nonpatched . Only one patient with an occlusion had cerebrovascular symptoms . In this study recurrence of symptoms within 5 years of follow-up was independent of patching , yet patch closure reduced the risk of recurrent carotid stenosis in women but not in men OBJECTIVE : To define whether or not direct microscopic closure with or without the use of a vascular patch is advantageous in terms of clinical outcome and late vessel occlusion rates after microsurgical carotid endarterectomy . METHODS : Three hundred thirty-eight elective carotid endarterectomies in 315 patients were r and omized to direct arteriotomy or closure with a polyester collagen-coated vascular patch . Ten procedures did not follow the r and omization process because of technical difficulties and were excluded . Vessel patency ( duplex ultrasound ) and outcome were assessed during and immediately after surgery and at 4 and 12 months after surgery . RESULTS : Four-month ultrasound assessment ( n = 321 ) identified five occluded vessels : two in the patch group ( n = 149 ) and three in the direct closure group ( n = 172 ) . Six patients in the patch group had died or were significantly disabled at 4 months , compared with five in the direct closure group . At the 12-month assessment ( n = 313 ) , eight vessels had occluded : five from the patched group ( n = 146 ) and three from the direct closure group ( n = 167 ) . Eight patients in the patch group had died or were significantly disabled , compared with four in the direct closure group . No statistically significant difference between the two groups in terms of vessel occlusion , morbidity , or mortality was seen ( P > 0.1 ) . CONCLUSION : No difference in vessel patency and clinical outcome has been identified after microscopic patch angioplasty and direct arteriotomy repair . The authors conclude that there is no benefit from the routine use of patch angioplasty in microscopic carotid endarterectomy There is much controversy in the literature regarding the precise role of patch angioplasty in carotid endarterectomy . Our report summarizes the theoretical and experimental considerations , including the hemodynamic effects and biologic behavior of the graft , associated with this technique . We present a detailed review of the literature regarding the clinical efficacy of patch angioplasty in carotid endarterectomy , including the early results , the late results , and the incidence and nature of carotid restenosis  . We address concerns about the use of patch angioplasty , including the duration of cross-clamping , potential problems with the graft and suture-line disruption , and graft atherogenesis . We conclude that most recent literature indicates that patch angioplasty decreases acute complications ( notably carotid occlusion ) after carotid endarterectomy and prevents or delays carotid restenosis . As pressure increases to achieve a minimal rate of perioperative morbidity , many surgeons are expected to adopt patch angioplasty in more of their cases . However , in the absence of conclusive results from a prospect i ve r and omized study , opinion will continue to be divided regarding the routine versus the selective use of patch grafting in carotid endarterectomy . We present criteria for r and omized trials of this technique INTRODUCTION The use of synthetic patch angioplasty during carotid endarterectomy ( CEA ) has been advocated to reduce restenosis , stroke , and death , but the type of material used is still being debated . This study compared rate of restenosis , neurologic events , and perioperative death in patients undergoing CEA with primary closure versus polyester urethane patch closure .  PATIENTS AND METHODS In a prospect i ve r and omized study , we compared patch angioplasty with polyester urethane ( Vascular-patch , B. Braun Medical AG , Tuttlingen , Germany ) to primary closure between February 1999 and March 2002 in 404 operations . Early ( 30-day ) stroke and mortality rate , long-term restenosis , and neurologic events were compared in the two groups during 2.5 to 5 years of follow-up ( median follow-up , 2 years ) . RESULTS  Primary closure  was used in 216 operations , and patch angioplasty was used in 206 . Clamping time was significantly shorter in the primary closure group ( P < .001 ) . Perioperative mortality and neurologic events were similar in both groups ( 1.9 % vs 3.9 % , P = .21 , odds ratio [ OR ] , 2.1 ; 95 % confidence interval [ CI ] , 0.56 to 9.85 ) . The rate of residual stenosis ( > or = 5 
    Output:
    
No significant correlation was found between use of patch angioplasty and the risk of either perioperative or long-term all-cause death rates .
AUTHORS ' CONCLUSIONS Limited evidence suggests that carotid patch angioplasty may reduce the risk of perioperative arterial occlusion and restenosis .
It would appear to reduce the risk of ipsilateral stroke and there is a non significant trend towards a reduction in perioperative any stroke rate and all-cause case fatality