Bilateral Endograft Limb Occlusion after Endovascular Aortic Repair: Predictive Factors of Occurrence.

BACKGROUND: Bilateral limb occlusion after endovascular aortic repair (EVAR) is relatively uncommon. The aim of this study was to investigate the incidence of bilateral endograft limb occlusion after EVAR and identify potential anatomical predictive factors of occurrence. METHODS: A total of 579 patients underwent elective EVAR for abdominal aortic aneurysm between January 2010 and December 2015. All patients presenting with unilateral and bilateral occlusions were prospectively analyzed. A group of patients who underwent EVAR but did not present with endograft limb occlusion were matched for sex, age, and commercial type of endograft and were used as controls. RESULTS: Overall, 21 (3.6%) patients were complicated with unilateral endograft limb occlusion, whereas 8 (1.4%) of them presented with sequential (in different time) bilateral limb occlusion. We found that iliac artery angulation ≥60°, iliac perimeter calcification ≥50%, and endograft oversizing in the common iliac artery of more than 15% had the same impact and could equally result in limb occlusion. We coded the variables angle, calcification, and endograft limb oversizing of the common iliac artery with a score from 0 to 2 as follows: (1) 0: angle <60° in both limbs, 1: angle ≥60° in one limb, 2: angle ≥60° in both limbs; (2) 0: calcification <50%: in both limbs, 1: calcification ≥ 50%: in one limb, 2: calcification ≥ 50%: in both limbs; and (3) 0: endograft limb oversizing <15%, 1: endograft limb oversizing ≥15% in one limb, 2: endograft limb oversizing ≥15% in both limbs. A composite variable, consisting of the sum of scoring in variables was analyzed, with a score from 0 to 6. Our study showed that it was the most probable to be in the control group when score in the composite variable was 0-3, it was the most probable to have unilateral limb occlusion when score was 4-5, and finally, it was the most probable to have bilateral limb occlusion when score in the composite variable was equal to 6. CONCLUSIONS: Our study evidenced that the highest probability for bilateral limb occlusion occurred when implantation of a more than 15% oversized endograft in iliac arteries with iliac artery angulation ≥60° and iliac perimeter calcification ≥50% was present in both iliac arteries. It is therefore clear that limb occlusion requires the synergistic effect and interaction of bilateral multiple thrombogenic components in the iliac artery before it is manifested.

Acute Early Carotid Stent Thrombosis: A Case Series.

BACKGROUND: Acute early carotid stent thrombosis (AcuteCST) is a rare complication after carotid artery stenting (CAS). The purpose of this retrospective study was to investigate the incidence, causes, and optimal management of AcuteCST. METHODS: Medical records of all patients undergoing CAS between 2008 and 2016 were retrospectively reviewed. The time of thrombosis, grade of stenosis, lesion side, preprocedural and postprocedural anticoagulants, causes, symptoms, treatment, recanalization, and outcome were reviewed. RESULTS: Overall, 674 patients were treated with CAS. Four cases of AcuteCST were identified (0.59%). In the first patient, the stent thrombosis was attributed to dissection caused by filter deployment within a distal internal carotid artery with 360° coiling. Notably, in 3 of the 4 cases of thrombosis a second overlapping stent had been deployed. In total, 41 patients of the cohort under investigation underwent overlapping stent deployment. The use of a second overlapping stent as a bail-out procedure due to dissection or malposition or due to long lesions was correlated with increased rate of thrombosis (3/41 [7.3%] vs. 1/633 [0.002%]). In 2 patients, carotid stents were thrombosed within 2 hr of the procedure. Endovascular thrombus aspiration and subsequent eversion carotid endarterectomy with stent explantation in the first patient and intrathrombus urokinase administration with thromboaspiration and additional stent placement in the second patient were followed. In the other 2 patients having their carotid stents thrombosed 3 and 4 days after the procedure, treatment with low weight molecular heparin and antiplatelet regimens was followed. CONCLUSIONS: The use of overlapping stents in the carotid artery is a predisposing factor for AcuteCST. Prognostic factors of this potentially devastating complication are the initial clinical presentation expressing the grade of ischemic brain damage, the accurate and timely recognition of the thrombosis, and the prompt restoration of oxygenated blood flow into the viable tissue at risk of infarction.

Acute Carotid Stent Thrombosis: A Comprehensive Review.

Acute carotid stent thrombosis (ACST) is a rare complication that can lead to dramatic and catastrophic consequences. A rapid diagnosis and prompt recanalization of the internal carotid artery are needed to minimize the ischemic insult and the reperfusion injury. We reviewed the current literature on this devastating complication of CAS with the intention of investigating the potential causative factors and to define the appropriate management. According to our study discontinuation of antiplatelet therapy, resistance to antiplatelet agents and inherent or acquired thrombotic disorders are the main causes of thrombosis. Technical intraprocedural parameters such as dissection, atheroma prolapse, kinking of the distal part of internal carotid artery and embolic protection device occlusion can also result in early carotid stent thrombosis. Rapid reperfusion ensures an improved neurological outcome and a better prognosis in the short and long term. Thrombolysis, mechanical thrombectomy or thromboaspiration in combination with drug or thrombolytic therapy, surgical therapy and re-angioplasty are treatment options that have been used with encouraging results. In conclusion, optimal perioperative antiplatelet treatment as well as technical considerations regarding the carotid artery stenting plays a determinant role.

A meta-analysis of combined endarterectomy and proximal balloon angioplasty for tandem disease of the arch vessels and carotid bifurcation.

OBJECTIVE: High grade stenoses of both the innominate (IA) or common carotid artery (CCA) and the carotid bifurcation are rare and represent a therapeutic dilemma for the treating physician. A hybrid procedure with concomitant carotid endarterectomy (CEA) and retrograde angioplasty has been proposed as a less invasive treatment option. The aim of this study is to review the existing literature on such hybrid procedures. METHODS: An electronic search of the pertinent English literature was undertaken. A meta-analysis of all studies reporting on simultaneous carotid endarterectomy and retrograde angioplasty for the treatment of tandem internal carotid and proximal common carotid or innominate artery lesions was performed. RESULTS: Thirteen studies, including 133 patients were identified. Sixty-eight percent of the patients were male, 83% symptomatic. Proximal lesions were located in ipsilateral CCA in 85 cases and in IA in 48 cases. Reported technical success of the procedure was 97%. In 79 of the 129 successful operations, a stent was implanted, while the remaining 50 patients underwent simple balloon angioplasty. Thirty-day mortality and stroke rate were 0.7% and 1.5%, respectively. Combined 30-day mortality and stroke rate was 1.5%. During a mean follow-up of 12 to 36 months, five patients presented symptoms of cerebral ischemia and 17 died. Ten patients developed restenosis of the proximal lesion, (4 symptomatic, 7 in cases without stent) and 2 restenoses of the endarterectomy (all asymptomatic). Restenosis was treated in 7 cases (4 repeat angioplasty, 3 bypass grafts). CONCLUSIONS: This meta-analysis reports the largest collection of patients having undergone hybrid treatment of tandem disease of the arch vessels and carotid bifurcation. Results from this study show that the combined stroke and death rate with this approach is equal to or better than that for isolated endarterectomy. When possible, balloon angioplasty with stenting of the proximal component of this disease should be pursued to avoid restenosis.

Endovascular management of malperfusion in acute type B aortic dissections.

PURPOSE: To examine the feasibility, efficacy, and midterm results of endovascular stent-graft management of acute type B aortic dissection complicated by renal, visceral, or lower limb malperfusion. METHODS: A retrospective review was conducted to identify all patients with acute type B dissection treated endovascularly at a single center between 1998 and 2009. Of the 85 patients identified, 23 (27%) consecutive patients (20 men; mean age 60.9 ± 11.6 years) presented with clinical and imaging evidence of end-organ malperfusion: 7 (30%) renal, 6 (26%) lower limb, 4 (17%) renal and lower limb, 3 (13%) visceral, and single cases of renal/visceral, renal/lower limb/spinal cord, and renal/visceral/spinal cord/lower limb. RESULTS: All patients had stent-graft coverage of the proximal entry tear; 5 (22%) patients required additional branch vessel stenting, and 2 (9%) had femorofemoral bypass graft. Successful correction of malperfusion was achieved in 21 (91%) patients. In 1 patient, ischemia in the lower limb was resolved but not in the left kidney; the other patient had an ischemic but viable lower limb and did not require any additional intervention. Thirty-day mortality was 9% (2/23 patients). The incidences of postoperative stroke and paraplegia were 17% (4/23) and 9% (2/23), respectively. The 21 survivors were followed for 17.2 ± 15 months; during this period, 1 patient died, 1 was lost to follow-up, and 5 patients underwent additional open or endovascular procedures. CONCLUSION: Endovascular coverage of the proximal entry tear in acute type B dissections complicated by end-organ malperfusion resulted in correction of malperfusion in the majority of patients. It is a reasonable first line of treatment, but its superiority must be assessed in comparison with other techniques, such as fenestration.

Colonic ischemia after endovascular exclusion of an aortoiliac aneurysm using an iliac branch device.

PURPOSE: To present the first case of colonic ischemia (CI) after endovascular exclusion of an aortoiliac aneurysm using an iliac branch device (IBD). CASE REPORT: A 69-year-old male patient with an abdominal aortic and right common iliac artery aneurysm underwent endovascular repair with an IBD. Completion angiography demonstrated good patency in 2 of the 3 main branches of the right internal iliac artery (IIA) whereas the left IIA patency was preserved. Preoperatively, the inferior mesenteric artery (IMA) was patent. Postoperatively, the patient presented moderate CI. He was treated conservatively and discharged 15 days later with recession of the symptoms. CONCLUSION: Although preservation of bilateral iliac artery patency is considered to diminish the incidence of pelvic ischemia, in case of an exclusion of a patent IMA, collaterals may not be adequate to ensure blood supply to the left colon.

Clinical relevance and treatment of carotid stent fractures.

OBJECTIVE: To review all published reports and investigate the clinical relevance and need for treatment of carotid stent fractures. METHODS: Electronic and hand-searching of the published literature and the Manufacturer and User Facility Device Experience (MAUDE) database. RESULTS: Thirteen articles were published. There are 10 case reports and 3 clinical studies. There are 26 reports of fractured stents in the MAUDE database. Fifty-five cases of carotid stent fractures are reported in total. A total of 201 carotid stents were examined in the 3 studies, and the incidence of fractures was 8.9% (18/201). Fractured stents were 22 Xact, 20 Acculink, 6 Precise, 2 Exponent, 1 Nexstent, 1 Genesis, 1 Symbiot, and 2 nonspecified nitinol self-expandable stents. Twenty-seven of the treated carotid lesions were atherosclerotic, 3 restenoses after carotid endarterectomy, 2 postradiational, 1 pseudoaneurysm, and 22 lesions of unknown pathology. Calcification was reported in 15 of the 27 atherosclerotic lesions (55.5%). Time from implantation to fracture ranged from 0 days (fracture during implantation) to 37 months. In 55% of the cases, stent fracture was associated with restenosis. Six patients presented with symptoms. Treatment was reported for 32 patients: 14 patients underwent de novo stent placement, 2 balloon angioplasty, 2 carotid endarterectomy, 2 bypass graft (1 vein, 1 polytetrafluoroethylene), 1 anticoagulation, and 11 patients were followed up. CONCLUSION: Carotid stent fractures are mainly reported in self-expandable nitinol stents. Plaque calcification may be a risk factor for stent fractures. No difference was observed between open and closed-cell design. Stent fractures were often associated with restenosis and usually were asymptomatic. The actual incidence, clinical relevance, and optimal treatment remain to be clarified from larger prospective studies designed to investigate the issue.

Endovascular stent-graft repair of major abdominal arteriovenous fistula: a systematic review.

PURPOSE: To evaluate the outcomes of endovascular stent-graft repair of major abdominal arteriovenous fistulas. METHODS: The English literature was systematically searched using the MEDLINE electronic database up to January 2009. All reports on endovascular stent-graft repair of major abdominal arteriovenous fistula were considered. Our experience of abdominal arteriovenous fistula was involved in the data analysis. The primary outcome measures were technical success and perioperative, 30-day, and overall mortality. RESULTS: Data for the final analysis were extracted from 21 papers reporting on 22 patients and from the medical records of a patient treated at our institution. The most common causal associations of these fistulae were the presence of an aortoiliac aneurysm and previous endovascular aneurysm repair, accounting for 56% and 13% of all associations, respectively. The technical success rate was 96% (22/23). No perioperative or 30-day mortality was noticed during a mean follow-up of 9 months. The most common procedure-related complication was type II endoleak, which was found in 22% (5/23) of the patients. This event was either self limiting or required minimal percutaneous intervention. CONCLUSION: Endovascular stent-graft repair of major abdominal arteriovenous fistula is a safe and effective treatment option, with good short- and midterm results. However, no long-term data exist, and larger series are required to draw solid conclusions regarding the outcomes of this method.

Hyperperfusion syndrome after carotid revascularization.

Cerebral hyperperfusion syndrome is a rare, serious complication of carotid revascularization either after carotid endarterectomy or carotid stent placement. Impaired cerebral autoregulation and post-revascularization changes in cerebral hemodynamics are the main mechanisms involved in the development of the syndrome. Hyperperfusion syndrome may be fatal once an intracranial hemorrhage occurs. This article reviews the literature, intending to make a synthesis of all new data concerning the clinical manifestations of hyperperfusion syndrome, the pathophysiologic pathways involved in its development, the prediction, and the appropriate management. Also, a review of the most recent series of hyperperfusion syndrome following carotid revascularization, both with classic open endarterectomy and carotid artery stenting has been performed.

Cerebral hyperperfusion after carotid stenting: a transcranial doppler and SPECT study.

AIM: To document the incidence of symptomatic cerebral hyperperfusion after carotid stenting and to determine possible predisposing factors. METHODS: A prospective study of 29 consecutive patients undergoing carotid stenting. All patients underwent 1) brain computed tomography scan and magnetic resonance imaging, 2) transcranial Doppler including assessment of cerebrovascular reactivity of the ipsilateral middle cerebral artery and 3) 99m hexamethyl-propyleneamine oxime brain single photon emission computed tomography, before and after the procedure. RESULTS: A total of 5 patients developed adverse neurological events, 4 of them transient. Cerebral hyperperfusion was documented in two of these (6.9%). Both had exhausted cerebrovascular reactivity in the preoperative transcranial Doppler examination. No consistent pattern of interhemispheric asymmetry in brain perfusion was found in these patients. CONCLUSIONS: Symptomatic cerebral hyperperfusion is not uncommon after carotid stenting. There seems to be a link between exhausted cerebrovascular reactivity of the ipsilateral middle cerebral artery and increased risk of cerebral hyperperfusion.

Endovascular treatment of a ruptured para-anastomotic aneurysm of the abdominal aorta.

We report a case of a ruptured para-anastomotic aortic aneurysm treated with implantation of a bifurcated stent-graft. A 72-year-old patient, who had undergone aortobifemoral bypass for aortoiliac occlusive disease 16 years ago, presented with a ruptured para-anastomotic aortic aneurysm. A bifurcated stent-graft was successfully deployed into the old bifurcated graft. This is the first report of a bifurcated stent-graft being placed through an "end-to-side" anastomosed old aortobifemoral graft. Endovascular treatment of ruptured para-anastomotic aortic aneurysms can be accomplished successfully, avoiding open surgery which is associated with increased mortality and morbidity.

Interhemispheric asymmetry in brain perfusion before and after carotid stenting: a 99mTc-HMPAO SPECT study.

PURPOSE: To assess the effect of unilateral carotid angioplasty and stenting (CAS) on cerebral perfusion asymmetry in patients with severe extracranial carotid stenosis by means of technetium Tc 99m hexamethyl-propyleneamine oxime brain single photon emission computed tomography ((99m)Tc-HMPAO SPECT). METHODS: Twenty-nine consecutive patients (22 men; median age 68 years, range 58-80; 13 symptomatic) undergoing unilateral CAS were included in the study. Brain perfusion was assessed by (99m)Tc-HMPAO brain SPECT prior to the procedure and postoperatively at 8 hours and at 2 to 4 months. The asymmetry index (AI), a measure of the interhemispheric asymmetry in perfusion, was calculated as [(counts in "healthy" hemisphere-counts in hemisphere with carotid stenosis)/counts in "healthy" hemisphere]x100. RESULTS: The preoperative AI demonstrated a wide variation (mean -0.5%+/-8.4%, range -19.5% to 14.1%). There was no significant correlation between the degree of carotid stenosis and preoperative AI. The mean preoperative AI in the asymptomatic patients was lower than in the symptomatic group [-4.0%+/-8.5% (range -19.5% to 8.2%) versus 3.8%+/-6.4% (range -5.2% to 14.1%), p=0.01], suggesting reduced perfusion of the ipsilateral cerebral hemisphere compared to the contralateral side in symptomatic patients. AI variation did not improve after CAS; there was no difference in AI among the 3 SPECT studies (p=0.75). Preoperative AI correlated significantly with late AI (r=0.74, p<0.0001); however, there was no statistically significant correlation between immediate postoperative AI and either preoperative (r=0.24, p=0.217) or late (r=0.24, p=0.249) AI. CONCLUSION: Asymmetry in cerebral perfusion in patients with severe extracranial carotid atherosclerosis does not correlate with the degree of carotid stenosis. Symptomatic patients demonstrate compromised perfusion of the ipsilateral hemisphere compared to asymptomatic patients. As judged by (99m)Tc-HMPAO SPECT scanning, cerebral perfusion patterns do not significantly change after CAS.