Shadi Abu-Halimah

Optimal carotid duplex velocity criteria for defining the severity of carotid in-stent restenosis

BACKGROUND The optimal duplex ultrasound (DUS) velocity criteria to determine in-stent carotid restenosis are controversial. We previously reported the optimal DUS velocities for >or=30% in-stent restenosis. This prospective study will further define the optimal velocities in detecting various severities of in-stent restenosis: >or=30%, >or=50%, and 80% to 99%. METHODS The analysis included 144 patients who underwent carotid artery stenting as a part of clinical trials. All patients had completion arteriograms and underwent postoperative carotid DUS imaging, which was repeated at 1 month and every 6 months thereafter. Patients with peak systolic velocities (PSVs) of the internal carotid artery (ICA) of >or=130 cm/s underwent carotid computed tomography (CT)/angiogram. The PSVs and end-diastolic velocities of the ICA and common carotid artery (CCA) and the PSV of the ICA/CCA ratios were recorded. Receiver operating characteristic curve (ROC) analysis was used to determine the optimal velocity criteria for the diagnosis of >or=30, >or=50, and >or=80% restenosis. RESULTS The mean follow-up was 20 months (range, 1-78 months). Available for analysis were 215 pairs of imaging (DUS vs CTA/angiography) studies. The accuracy of CTA vs carotid arteriogram was confirmed in a subset of 22 patients (kappa = 0.81). The ROC analysis demonstrated that an ICA PSV of >or=154 cm/s was optimal for >or=30% stenosis with a sensitivity of 99%, specificity of 89%, positive-predictive value (PPV) of 96%, negative-predictive value (NPV) of 97%, and overall accuracy (OA) of 96%. An ICA EDV of 42 cm/s had sensitivity, specificity, PPV, NPV, and OA in detecting >or=30% stenosis of 86%, 62%, 87%, 60%, and 80%, respectively. An ICA PSV of >or=224 cm/s was optimal for >50% stenosis with a sensitivity of 99%, specificity of 90%, PPV of 99%, NPV of 90%, and OA of 98%. An ICA EDV of 88 cm/s had sensitivity, specificity, PPV, NPV, and OA in detecting >or=50% stenosis of 96%, 100%, 100%, 100%, 53%, and 96%. An ICA/CCA ratio of 3.439 had sensitivity, specificity, PPV, NPV, and OA in detecting >or=50% stenosis of 96%, 100%, 100%, 100%, 58%, and 96%, respectively. An ICA PSV of >or=325 cm/s was optimal for >80% stenosis with a sensitivity of 100%, specificity of 99%, PPV of 100%, NPV of 88%, and OA of 99%. An ICA EDV of 119 cm/sec had sensitivity, specificity, PPV, NPV, and OA in detecting >or=80% stenosis of 99%, 100%, 100%, 100%, 75%, and 99%, respectively. The PSV of the stented artery was a better predictor for in-stent restenosis than the end-diastolic velocity or ICA/CCA ratio. CONCLUSION The optimal DUS velocity criteria for in-stent restenosis of >or=30%, >or=50%, and >or=80% were the PSVs of 154, 224, and 325 cm/s, respectively.

Carotid artery stenting outcomes are equivalent to carotid endarterectomy outcomes for patients with post-carotid endarterectomy stenosis

BACKGROUND Carotid artery stenting (CAS) has been advocated as an alternative to redo surgery for patients with post-carotid endarterectomy (CEA) stenosis. This study compares early and late clinical outcomes for both groups. METHODS This study analyzes 192 patients: 72 had reoperation (Group A) and 120 had CAS for post-CEA stenosis (Group B). Patients were followed prospectively and had duplex ultrasounds at 1 month, and every 6 to 12 months thereafter. The perioperative complications (perioperative stroke, myocardial infarction/death, cranial nerve injury) and 4-year end points were analyzed. A Kaplan-Meier lifetable analysis was used to estimate rates of freedom from stroke, stroke-free survival, ≥50% restenosis, and ≥80% restenosis. RESULTS Demographic/clinical characteristics were comparable for both groups, except for diabetes mellitus and coronary artery disease, which were significantly higher in Group B. The indications for reoperations were transient ischemic attacks/stroke in 72% for Group A versus 57% for Group B (P=.0328). The mean follow-up was 33 months (range, 1-86 months) for Group A and 24 months (range, 1-78 months) for Group B (P=.0026). The proportion of early (<24 months) carotid restenosis prior to intervention was 51% in Group A versus 27% in Group B (P=.0013). The perioperative stroke rates were 3% and 1%, respectively (P=.5573). There were no myocardial infarctions or deaths in either group. The overall incidence of cranial nerve injury was 14% for Group A versus 0% for Group B (P<.0001). However, there was no statistical difference between the groups relating to permanent cranial nerve injury (1% versus 0%). The combined early and late stroke rates for Groups A and B were 3% and 2%, respectively (P=.6347). The stroke-free rates at 1, 2, 3, and 4 years for Groups A and B were 97%, 97%, 97%, and 97% and 98%, 98%, 98%, and 98%, respectively (P=.6490). The stroke-free survival rates were not significantly different. The rates of freedom from ≥50% restenosis at 1, 2, 3, and 4 years were 98%, 95%, 95%, and 95% for Group A versus 95%, 89%, 80%, and 72% for Group B (P=.0175). The freedom from ≥80% restenosis at 1, 2, 3, and 4 years for Groups A and B were 98%, 97%, 97%, and 97% versus 99%, 96%, 92%, and 87%, respectively (P=.2281). Four patients (one symptomatic) in Group B had reintervention for ≥80% restenosis. The rate of freedom from reintervention for Groups A and B were 100%, 100%, 100%, and 100% versus 94%, 89%, 83%, and 79%, respectively (P=.0634). CONCLUSIONS CAS is as safe as redo CEA. Redo CEA has a higher incidence of transient cranial nerve injury; however, CAS has a higher incidence of ≥50% in-stent restenosis.

Predictors of percutaneous access failure requiring open femoral surgical conversion during endovascular aortic aneurysm repair

OBJECTIVE To determine predictors of percutaneous (PEVAR) access failure requiring conversion to an open approach (OEVAR) during endovascular aortic aneurysm repair (EVAR). METHODS A single-center retrospective review of all EVAR patients from January 2009 through June 2011 with multivariate analysis of clinical and anatomic variables that could impact access outcome was conducted. Target vessel calcification was categorized as mild, moderate, or severe based on circumferential calcium arc (<⅓, ⅓ to ½, and >½ respectively), dyslipidemia (defined as low-density lipoprotein >130 mg/dL or receiving lipid lowering medication), and obesity (defined as body mass index [BMI] >30). RESULTS We investigated 400 access sites for 200 patients who underwent EVAR. The study cohorts characteristics included an average age of 72.8 ± 9.0 years, vessel size of 9.6 ± 1.8 mm, sheath size of 17.1 ± 3.0 Fr, BMI of 27.6 ± 5.3, and estimated glomular filtration rate of 68.5 ± 24.2 mL/min. Comorbidities included dyslipidemia in 129 patients (64.5%) and diabetes in 54 patients (27%). There were 132 OEVAR (66 patients), two mixed OEVAR with contralateral PEVAR (one patient), and 266 (133 patients) PEVAR approaches. Use of PEVAR increased over time (45.5% [2009], 77.8% [2010], and up to 88.5% [2011]; P = .001) while conversions decreased (24.3% [2009], 8.7% [2010], and 4.3% [2011]; P = .001]. More OEVAR patients (35.8%) stayed longer than 3 days compared with 21.1% for PEVAR (P = .028). For the 266 PEVAR approaches, 32 access sites (12.0%) had to be converted. Severely calcified arteries were most predictive of conversion (odds ratio [OR], 36.4; P < .001). Year of procedure (2010; OR, 0.17; P = .001; 2011, OR, 0.20; P = .049), female gender (OR, 3.1; P = .017), moderately calcified arteries (OR, 2.5; P = .085), and age (OR, 2.3 [per decade]; P = .002) were all also significant. Vessel size, sheath size, and BMI were found to be nonsignificant predictors of conversion. CONCLUSIONS PEVAR was found to be safe, reliable, and feasible. Several factors, including learning curve, vessel calcification, age, and female gender predicted conversion of PEVAR to OEVAR.

Primary carotid artery stenting versus carotid artery stenting for postcarotid endarterectomy stenosis

BACKGROUND Carotid artery stenting (CAS) has been advocated as an alternative to carotid endarterectomy (CEA) in high-risk surgical patients, including stenosis after CEA. This study compared early and midterm clinical outcomes for primary CAS vs CAS for post-CEA stenosis. METHODS This study analyzed 180 high-risk surgical patients: 68 had primary CAS (group A), and 112 had CAS for post-CEA stenosis (group B). Patients were followed-up prospectively and had duplex ultrasound imaging at 1 month and every 6 months thereafter. All patients had cerebral protection devices. Kaplan-Meier life-table analysis was used to estimate rates of freedom from stroke, stroke-free survival, > or =50% in-stent stenosis, > or =80% in-stent stenosis, and target vessel reintervention (TVR). RESULTS Patients had comparable demographic and clinical characteristics. Carotid stent locations were similar. Indications for CAS were transient ischemic attacks (TIA) or stroke in 50% for group A and 45% for group B. The mean follow-up was comparable, at 21 (range, 1-73) vs 25 (range, 1-78) months, respectively. The technical success rate was 100%. The perioperative stroke rates and combined stroke/death/myocardial infarction (MI) rates were 7.4% for group A vs 0.9% for group B (P = .0294). No perioperative MIs occurred in either group. One death was secondary to stroke. The combined early and late stroke rates were 10.8% for group A and 1.8% for group B (P = .0275). The stroke-free rates at 1, 2, 3, and 4 years for groups A and B were 89%, 89%, 89%, and 89%; and 98%, 98%, 98%, and 98%, respectively (P = .0105). The rates of freedom from > or =50% carotid in-stent stenosis were 94%, 83%, 83%, and 66% for group A vs 96%, 91%, 83%, and 72% for group B (P = .4705). Two patients (3%) in group A and seven patients (6.3%) in group B had > or =80% in-stent stenosis (all were asymptomatic except one). The freedom from > or =80% in-stent stenosis at 1, 2, 3, and 4 years for groups A and B were 100%, 98%, 98%, and 78% vs 99%, 96%, 92%, and 87%, respectively (P = .7005). Freedom from TVR rates at 1, 2, 3, and 4 years for groups A and B were 100%, 100%, 100%, and 100% vs 99%, 97%, 97%, and 92%, respectively (P = .261). CONCLUSIONS CAS for post-CEA stenosis carried a lower risk of early postprocedural neurologic events than primary CAS, with a trend toward a higher restenosis rate during follow-up.

Complications of diagnostic carotid/cerebral arteriography when performed by a vascular surgeon

Carotid stenting has recently been considered as an alternative treatment to carotid endarterectomy for certain patients with carotid stenosis. Hence, performing carotid arteriography with minimal morbidity and mortality is essential. The purpose of this study was to audit complications of diagnostic carotid/cerebral arteriography performed by a vascular surgeon with experience in endovascular interventions. One hundred one consecutive patients underwent 4-vessel arch aortography with selective carotid, subclavian, and/or vertebral arteriography with use of the Seldinger technique. Demographic data, indications, procedure approach (transfemoral, brachial), number of arteries punctured, type of selective injection, contrast volume, and procedure time were analyzed. Minor complications were those that do not significantly alter the health or activity of the patient or require extra hospitalization or treatment. Other complications were defined as major complications. The technical success rate was 99% (100/101 patients). These included the following: 82 patients with right carotid artery, 82 with left carotid artery, 15 with right subclavian artery, 21 with left subclavian artery, 11 with right vertebral artery, and 17 with left vertebral artery (a total of 228 selective injections). Indications for procedures included the following: transient ischemic attack (TIA)/stroke symptoms in 66%, asymptomatic carotid stenosis in 22%, upper limb claudication in 4%, and vertebrobasilar insufficiency in 4%. Right femoral puncture was used in 79%, left femoral in 12%, and left brachial in 9%. The mean amount of contrast used was 101 cc (45-250 cc) and the mean procedure time was 46 minutes (22-132 minutes). There were 5 complications in the whole series: 3 major complications (3%), including 1 minor stroke (1%) with carotid injection, 1 TIA, and 1 major retroperitoneal bleeding; and 2 (2%) minor complications. The major complication rate in this series compares favorably to published rates of 5.7% to 9.1%. There was no association between complications and specific risk factors except for a longer catheterization time (66 minutes versus 45 minutes, p= 0.011). Carotid/cerebral arteriography can be done safely by experienced vascular surgeons with minimal perioperative complications that compare favorably with what has been reported in the radiology literature.

Patency in Arteriovenous Grafts in Hemodialysis Patients

Objective: It is difficult to maintain a working access for patients on hemodialysis. Despite current Dialysis Outcome Quality Initiatives recommendations of “Fistula First,” not everyone qualifies for a fistula, and those patients undergoing the alternative treatment, a graft, can experience graft failure. This study examines factors associated with arteriovenous graft (AVG) patency. Methods: A retrospective analysis was completed for all the patients who had an AVG during 2005 to 2010. Data were collected from electronic medical records, including date of first and subsequent interventions, salvage technique (surgical vs percutaneous), medical comorbidities, and use of antiplatelet medications (aspirin and clopidogrel). Continuous variables were compared with 2 sample t tests, and categorical variables with chi-square/Fisher exact test. Logistic regression was used to determine the odds ratio for risk factors associated with patency. A P value of <.05 was considered significant. All analyses were done using SAS 9.2 (SAS Institute Inc, Cary, North Carolina). Results: A total of 193 unique patients had an AVG. Of the 193 patients, 64% were female, 83% were hypertensive, and 64% were diabetic. The locations of the grafts were 80% arm, 15% forearm, and 5% thigh. Configurations, including loop and straight, were 34% and 63%, respectively. Comorbidities were not associated with patency. Primary patency was not found to be different with respect to location and configuration of graft and type of intervention. Primary patency for patients taking only aspirin (n = 43) and only clopidogrel (n = 17) were significantly different from patients on a combination of aspirin and clopidogrel (n = 7), with a P = .0051 and P = .0447, respectively. Conclusion: Neither location nor configuration affects the primary patency of AVGs. Aspirin alone is not inferior to aspirin and clopidogrel. Further prospective studies may be warranted to establish a consensus regarding medications and patency with AVGs.

Impact of chronic renal insufficiency on the early and late clinical outcomes of carotid artery stenting using serum creatinine vs glomerular filtration rate.

BACKGROUND This study analyzed the impact of chronic renal insufficiency (CRI) on early and late clinical outcomes of carotid artery stenting (CAS) using serum creatinine and glomerular filtration rate (GFR). STUDY DESIGN There were 313 CAS patients classified into 3 groups: normal (serum creatinine <1.5 mg/dL or GFR ≥ 60 mL/min/1.73 m(2)); moderate CRI, and severe CRI (serum creatinine ≥ 3 or GFR < 30 mL/min/1.73 m(2)). Major adverse events ([MAE] stroke, death, and myocardial infarction) were compared for all groups. RESULTS Using serum creatinine, perioperative stroke rates for normal, moderate, and severe CRI were: 5%, 0%, and 25%, respectively, (p = 0.05) vs 4.6%, 3.7%, and 11.1%, respectively, (p = 0.44) using GFR. The perioperative MAE rates for symptomatic patients were 9.3% and 0% (p = 0.355) and 2% and 5.9% (p = 0.223) for asymptomatic patients for normal and moderate/severe CRI, respectively, using serum creatinine vs 8.1% and 7.8%, respectively, for symptomatic patients and 2.5% and 3%, respectively, for asymptomatic patients using GFR. At a mean follow-up of 21 months, late MAE rates in normal vs moderate/severe CRI patients were 8.2% and 14%, respectively, (p = 0.247) using serum creatinine vs 6.6% and 13.3%, respectively, (p = 0.05) using GFR. Late MAE rates for symptomatic patients in normal vs moderate/severe CRI were: 8.7% vs 27%, respectively, (p = 0.061) using serum creatinine and 5.7% vs 18.8%, respectively, (p = 0.026) using GFR. Late death rate was 0.55% in normal vs 7.6% (p = 0.002) for moderate/severe CRI. Freedom from MAE at 3 years in symptomatic patients was 81% in normal and 46% in moderate/severe CRI (p = 0.0198). A multivariate Cox regression analysis showed that a GFR of < 60 mL/min/1.73 m(2) had an odds ratio of 1.6 (p = 0.222) of having a MAE after CAS. CONCLUSIONS The GFR was more sensitive in detecting late MAE after CAS. Carotid artery stenting in moderate CRI patients can be done with a satisfactory perioperative outcome; however, late death was significant.

Cystic Adventitial Disease of the Common Femoral Vein A Case Report and Review of the Literature

We report on a 52-year-old female patient who presented with a 6-month history of right lower extremity swelling and tenderness. The patient was treated as an outpatient with full anticoagulation, without any improvement. Her medical history was significant for hypertension and high cholesterol, and she had a full coagulopathy profile that was negative for any hypercoagulable syndrome. On examination, the patient was moderately obese, with significant tenderness over the medial aspect of the right groin. A venous duplex examination revealed hypoechoic structure ± acute deep vein thrombosis of right common femoral vein (CFV). A computed tomography of the venous phase revealed an eccentric compression over the medial wall of the right CFV. During surgical exploration, adventitial cystic mucinous disease was enucleated from the medial wall of the right CFV, and the pathological examination confirmed the diagnosis. The postoperative course was uneventful, and all swelling and tenderness were completely resolved. The patient continued to do well, and she had an unremarkable venous duplex evaluation at her 6-month follow-up.

Current Update on the Status of Totally Percutaneous Aneurysm Repair

The evolution of minimally invasive procedures to treat aortic aneurysms has expanded to include access interventions as well. Traditionally, groin exposures have been the standard approach for common femoral artery exposure with open cutdown; however, inherent and related complications to that approach have paved the road to the percutaneous approach. Current available evidence from the literature supports the feasibility and the safety of percutaneous endovascular aneurysm repair (PEVAR); however, predictors of success are not well defined. We should examine all available studies (both prospective and retrospective) in order to draw a conclusion and evidence-based outcome for selecting patients who would benefit the most from PEVAR.

Clopidogrel use before renal artery angioplasty with/without stent placement resulted in tertiary procedure risk reduction

OBJECTIVE Contrary to coronary artery literature, the effect of preprocedural clopidogrel on renal artery restenosis (RAR) has not been characterized. This study was designed to evaluate the effect of preprocedural clopidogrel on target vessel revascularization (TVR), reintervention, and restenosis for patients who underwent recurrent renal artery angioplasty. METHODS A retrospective analysis of patients treated for RAR in a single tertiary center from January 1999 to December 2009 was conducted. Patients were divided into preadmission use of (1) clopidogrel or (2) aspirin only (acetylsalicylic acid [ASA]) for the initial procedure. TVR was defined as occurrence of a tertiary procedure for symptomatic RAR. Rate of freedom from event (ie, tertiary restenosis and TVR) was analyzed using Kaplan-Meier method. RESULTS Eighty-eight interventions were performed on 77 patients with RAR; 66% were females with average (mean ± SEM) age and body mass index of 68.8 ± 1.1 and 28.6 ± 0.8, respectively. Comorbidities included 96% chronic hypertension, 33% diabetes, 76% hyperlipidemia, 20% renal insufficiency, 39% tobacco use, 58% coronary artery disease, and 51% peripheral vascular disease. Clopidogrel use increased significantly during the index procedure from admission 35.2% to discharge 97.7% (P < .001, McNemar test). There was a trend toward risk reduction of a tertiary intervention (23%) for patients admitted on clopidogrel compared with ASA (P = .052). Likewise, there was a trend (P = .051) toward increased freedom from a tertiary intervention, with cumulative freedom at 8 years 93.5% for clopidogrel vs 61% for ASA. No differences were found for restenosis. CONCLUSIONS The use of preprocedural clopidogrel was associated with a possible risk reduction of TVR reintervention, but this finding needs to be validated in randomized clinical trial.