Primary versus patch closure after carotid endarterectomy: A retrospective study

ABSTRACT


INTRODUCTION
Carotid artery disease (CAD) has been suggested as a cause of ischemic stroke in 15.0-20.0% of cases.Globally, CAD is associated with significant morbidity and mortality burden.Available management options entail medical, surgical, and endovascular strategies [1].Despite the significant progress achieved in management of CAD patients, multiple uncertainties do still exist particularly appropriate selection of surgical intervention in asymptomatic cases [2].
For almost 70 years, carotid endarterectomy (CEA) has been considered for management of CAD.Surgical techniques have evolved over the years and currently, there are many variations among surgical practices worldwide.After CEA, the commonly used vascular closure procedures include patch closure (PAC) and primary closure (PRC) [3].
However, choice of the optimal closure technique remains debatable with inconsistent conclusions derived from systematic reviews and meta-analyses [4].In one work, based on moderate-quality evidence, it was suggested that PAC was associated with lower perioperative stroke and restenosis [5].In another review, it was supported PAC as a superior technique to PRC with level I evidence [6].In contrast, it was argued that there is no conclusive evidence indicative of a difference between PAC and PRC regarding 30-day stroke, mortality, or other serious adverse events [7].While the recent meta-analysis in [8] concluded that PAC may be associated with lower short and long-term risk of stroke and restenosis, they noted that evidence lacks certainty due to the imperfect quality of most included studies.
The present study aimed to contribute to this debate by providing our experience with PAC and PRC after CEA.

MATERIALS & METHODS
The present retrospective comparative study protocol was approved by the ethical committee.The study included 106 patients who submitted to elective CEA between June 2018 and June 2020.They comprised 50 patients in PRC group and 56 patients in PAC group at Al-Azhar University Hospitals.
Preoperatively, all patients were evaluated with duplex ultrasound.Internal carotid artery (ICA)/common carotid artery peak systolic velocity ratios were employed to measure the degree of carotid stenosis.Carotid artery stenosis was classified as mild if the ratio was between 0.1 and 1.9, moderate if the ratio was between 2.0 and 4.0, and severe if the ratio was greater than four (Figure 1).
A computed tomography angiogram or magnetic resonance angiogram were scheduled when the carotid artery stenosis reached 70.0% in asymptomatic cases and 50.0% in symptomatic patients, and eventually, CEA was conducted after gaining consent from the patients or their families.
CEA was conducted under general anesthesia utilizing conventional surgical techniques and recommendations.Preoperative findings like the clinical history, backpressure readings, and intraoperative electroencephalogram data guided the decision to do carotid shunting.Small ICA diameter (five mm), lengthy arteriotomy (extending more than three cm beyond ICA's origin), and kinked or looped ICA requiring resection were all criteria for obligatory PAC.Vein patches (saphenous or neck veins) and synthetic patches (dacron or polytetrafluoroethylene) were utilized as patch materials.After the procedure, cases were moved to the recovery unit for monitoring after surgery, with a maximum systolic blood pressure threshold of 150 to 160 mmHg.Patients were then monitored for 24 hours in the intensive care unit and transferred to the ward after systolic blood pressure remained less than the threshold for at least four hours.All patients were advised to be mobilized early on the first postoperative day.
The findings of doppler ultrasound scans for restenosis and complication assessment were compared to preoperative stenotic values at the following intervals: immediate (within seven days of CEA), three months, and one year.The operating team had consulted a stroke neurologist for additional evaluation of the patient if neurological issues were suspected.From the first day postoperative until discharge from hospital, all patients were given low molecular weight heparin on their body weight.After being discharged from hospital, all patients continued to take 75 mg clopidogrel, 100 mg acetylsalicylic acid, and 20 mg atorvastatin for at least six months.
The statistical program for social sciences, version 23.0, was utilized for data analysis.When comparing two means, the independent-samples t-test of significance was utilized.To compare proportions among qualitative factors, a Chi-square test of significance was performed.p-value less than 0.050 was considered statistically significant.
At three months, three patients in PRC group and four in PAC group were lost to follow up.No significant differences were found between the studied groups regarding rate of restenosis at three months (2.1% versus 0.0%, p=0.960).At one year, patients in PRC group experienced significantly higher rate of restenosis (14.9% versus 1.9%, p=0.046).None of the studied patients died (Table 3).

DISCUSSION & CONCLUSIONS
The present study sought to retrospectively compare the perioperative and 1-year outcome of patients submitted to PRC or PAC closure after CEA.Both techniques were comparable regarding perioperative complications and three months restenosis rate.But, at one year follow up, patients in PRC group experienced significantly higher rate of restenosis.Our findings are in line with the conclusions in [9] randomized study who reported that at two years of follow up, PAC was associated with significantly lower restenosis rate without affecting other clinical outcomes including periprocedural stroke and death, immediate reoperation, and risk of ipsilateral stroke.Similar findings were documented by the retrospective study in [10] on 110 and 103 patients submitted to PRC and PAC, respectively.Likewise, the study of in [11] on CEA patients submitted to PRC (n=232) or PAC (n=511) found that PRC had significantly higher restenosis rate at one year.Using bovine PAC was also associated with lower restenosis rate at a mean follow duration of 26.1±19.3months, as shown in [12].Of note, the recent Swedish registry-based study in [13] concluded that PRC is associated with higher risk of ipsilateral stroke <30 days with no difference between groups after the perioperative phase.
In contrast, one large study of 1,737 CEA patients, half of them had PAC and others had PRC and eversion closure found no significant differences between the studied groups regarding postoperative complications or stroke, mortality, or restenosis rates [14].Again, the retrospective study in [15] identified no differences between PRC and PAC in respect to stroke, mortality, restenosis, and other complications at one year.Other more recent studies reported concordant results including the retrospective studies in [16][17][18][19][20][21].
The contradictory conclusions of different studies are probably attributed to the different selection criteria of included patients, technical specifications, and different study designs.A multinational randomized study with unified technique and selection criteria is strongly advocated to resolve this issue.
Conclusively, the present study suggests that CEA combined with patch angioplasty may be associated with lower restenosis rate.It is a straightforward surgical procedure with short operative times and hospital stays.

Figure 1 .
Figure 1.Doppler ultrasound examination: (a) B-mode Doppler ultrasound examination revealed moderate stenosis of right internal carotid artery by an atheromatous plaque; (b) color Doppler ultrasound examination of right internal carotid artery after endarterectomy showing color flow with average PSV & EDV (reprinted with permission of the patient)

Table 1 .
Baseline characteristics in studied groups

Table 2 .
Postoperative complications in studied groups

Table 3 .
Restenosis rate in studied groups