Woo-Sung Yun

Carotid artery revascularization in patients with concomitant carotid artery stenosis and asymptomatic unruptured intracranial artery aneurysm.

BACKGROUND The incidence of concomitant carotid artery stenosis and unruptured intracranial aneurysm (UIA) has been reported to be between 3% and 5%. The rupture risk of UIA measuring <7 mm is very low according to International Study of Unruptured Intracranial Aneurysm data. However, there may be a potential risk of aneurysm rupture after carotid artery revascularization because of increased cerebral blood flow. The aims of this study were to investigate the incidence of concomitant UIA in patients who needed carotid artery intervention and to survey the incidence of aneurysm rupture after treatment. METHODS Between October 2004 and December 2009, 114 patients with severe carotid artery stenosis were treated in our hospital (69 carotid endarterectomies and 45 carotid artery stentings). Cerebral angiography and medical records were reviewed retrospectively. RESULTS Cerebral angiography revealed seven asymptomatic UIAs in six patients (5%, 6/114). Of them, four patients underwent carotid endarterectomy and two underwent carotid artery stenting. All patients were male, and the mean age of the patients was 72 years (range, 67-79 years). Aneurysm size ranged between 2.3 and 4.0 mm. Two patients had UIAs on the same side of the treated carotid artery, whereas others developed UIAs on the contralateral side. There was no periprocedural aneurysm rupture. During follow-up (mean: 18 months, 5-31 months), two patients died from other causes, and no rupture of aneurysm occurred in any of the patients. CONCLUSION In our series, the carotid artery revascularization did not have an effect on the natural course of small-sized asymptomatic UIA.

Iliac anatomy and the incidence of adjunctive maneuvers during endovascular abdominal aortic aneurysm repair

Purpose Challenging iliac anatomy remains an important issue during endovascular aneurysm repair (EVAR), and it is known that the length of the common iliac artery (CIA) is shorter in Asians than in Western groups. We analyzed both the iliac anatomy and the incidence of adjunctive maneuvers to overcome iliac artery-related difficulties during EVAR. Methods Seventy-four EVARs were performed for abdominal aortic aneurysm between January 2010 and March 2013. Patient demographic data, iliac anatomical characteristics (presence of iliac artery aneurysm, iliac artery diameter and length, and iliac tortuosity), and adjunctive iliac artery maneuvers were reviewed retrospectively. Results Mean CIA length was 52.8 mm (range, 6.6-98.0 mm) on the right and 56.3 mm (range, 0-94.8 mm) on the left. CIA length was ≥20 mm, except in one patient with bilateral short CIAs. Forty patients (54%) had a CIA aneurysm, and 18 had aneurysms on both sides. Iliac adjunctive procedures were performed in 38 patients (51%) as follows: 23 internal iliac artery (IIA) embolizations or ligations, seven IIA revascularizations, 16 external iliac artery (EIA) balloon angioplasties or stenting, one EIA patch angioplasty, one EIA interposition, two femoral endarterectomies with patch angioplasty, and nine femoro-femoral bypasses after EVAR with an aorto-uni-iliac device. Technical success for the adjunctive iliac procedures was achieved in all patients. Conclusion Short CIA length was uncommon. Although many patients had access-related difficulties, most were overcome by an endovascular or hybrid technique. Liberal use of iliac adjunctive procedures can facilitate EVAR.

Endovascular aortic aneurysm repair using a bifurcated stent graft in a patient with femoro-femoral bypass.

A challenging iliac anatomy remains a major obstacle to successful endovascular aortic aneurysm repair. The authors experienced an abdominal aortic aneurysm with bilateral common iliac artery aneurysms in a patient that had undergone femoro-femoral bypass due to left external iliac artery (EIA) occlusion. To treat this patient in a totally endovascular manner, a bifurcated stent graft was used. One iliac limb was deployed in the right internal iliac artery (IIA) and the other in the right EIA; the left IIA was embolized with coils. Here, the authors describe the procedure used and provide technical tips.

Long-Term Follow-Up Results of Acute Renal Embolism after Anticoagulation Therapy

BACKGROUND Acute renal embolism (ARE) is a rare cause of acute abdominal pain. However, there are only a few studies on the clinical course of ARE. We attempted to investigate the clinical manifestations and long-term follow-up results of ARE. METHODS From September 2006 to August 2012, 47 patients, who were diagnosed with ARE by computed tomography (CT), were enrolled. Patient demographic and clinical data were retrospectively reviewed. For the long-term outcomes, change in the serum creatinine (s-Cr) level, change in renal infarction on follow-up CT, recurrent embolism, and dialysis-free survival were investigated. RESULTS The mean age of patients was 61 years (range, 29-89 years), and 51% of the patients were men. All the patients presented with abdominal or flank pain. The sites of ARE were the right kidney in 57% of the patients, the left kidney in 36% of the patients, and both the kidneys in 6% of the patients. The infarction volume was less than 50% of renal volume in 54% of infarcted kidneys. Six patients had a concurrent infarction in other organs (3 cases of splenic infarction and 3 cases of cerebral infarction). Etiology of embolism was cardiogenic in 55% and idiopathic in 45%. Mean s-Cr level was 1.2 mg/dL (range, 0.6-3.7 mg/dL). s-Cr elevation >0.5 mg/dL was detected in 19% of patients during the follow-up (6 of 31 patients; mean duration, 31 months). Follow-up CT was performed in 23 patients (mean duration, 29 months). The infarcted lesions showed atrophic changes in all the cases except for 1 case. During the mean follow-up period of 41 months (1-118 months), recurrent embolism developed in 8 patients (6 cases of cerebral artery embolism, 1 case of superior mesenteric artery embolism, and 1 case of renal artery embolism). Dialysis was necessary in 1 patient, and dialysis-free survival rates were 91%, 82%, and 64% at 1 year, 3 years, and 5 years, respectively. CONCLUSIONS Although ARE causes irreversible loss of renal mass, it rarely leads to end-stage renal disease or long-term mortality. Therefore, the treatment should focus on the prevention of subsequent embolism to other vital organs.

The early and mid-term results of carotid artery stenting in high-risk patients

Purpose This study aimed to investigate early and mid-term outcomes of carotid artery stenting (CAS). Methods We retrospectively reviewed 111 patients who were treated for carotid stenosis between October 2004 and December 2009 (42 CASs and 69 carotid endarterectomies [CEAs]). Results CAS group was older than CEA group (70 years vs. 67 years, P = 0.001). Coronary artery disease and high lesion above the 2nd cervical vertebral body were more common in CAS group (29% vs. 13%, P = 0.002; 4% vs. 24%, P = 0.004). The 30-days stroke rate was higher in CAS group (10% vs. 1% in CEA group, P = 0.067, Fishers exact test). New brain lesions on diffusion-weighted magnetic resonance imaging were more common in CAS group (48% vs. 20% in CEA group, P = 0.002, chi-square test). The 1-, 3-year freedom from stroke were 91%, 84% in CAS group and 99%, 99% in CEA group (P = 0.007, log-rank test). Univariate analysis showed that female gender and age > 70 years were related with postprocedural neurological complications (P = 0.046 and P = 0.007, log-rank test). However, none were independent risk factors on multivariate analysis. Conclusion In our series, the rates of peri-procedural neurological complications in CAS group were significantly high. These results suggest that more experience and restricted patient selection will be needed for CAS.

Cerebral monitoring during carotid endarterectomy by transcranial Doppler ultrasonography

Purpose To evaluate the efficacy and safety of cerebral monitoring by transcranial Doppler ultrasonography (TCD) for the detection of cerebral ischemia during carotid endarterectomy (CEA). Methods From August 2004 to December 2013, 159 CEAs were performed in a tertiary hospital. All procedures were performed under general anesthesia. Intraoperative TCD was routinely used to detect cerebral ischemia. Of the 159 patients, 102 patients were included in this study, excluding 27 patients who had a poor transtemporal isonation window and 30 patients who used additional cerebral monitoring systems such as electroencephalography or somatosensory evoked potentials. When mean flow velocity in the ipsilateral middle cerebral artery decreased by >50% versus baseline during carotid clamping carotid shunting was selectively performed. The carotid shunt rate and incidence of perioperative (<30 days) stroke or death were investigated by reviewing medical records. Results Carotid shunting was performed in 31 of the 102 patients (30%). Perioperative stroke occurred in 2 patients (2%); a minor ischemic stroke caused by embolism in one and an intracerebral hemorrhage in the other. Perioperative death developed in the latter patient. Conclusion TCD is a safe cerebral monitoring tool to detect cerebral ischemia during CEA. It can reduce use of carotid shunt.