Jiang Xiong

Endovascular Chimney Technique of Aortic Arch Pathologies: A Systematic Review

BACKGROUND The aim of this review was to determine the safety and efficacy of endovascular chimney technique for aortic arch pathologies by performing a systematic and pooled analysis of the relevant literature. METHODS Electronic searches were performed in database Medline between 1994 and 2011 to identify studies on endovascular chimney technique for aortic arch pathology. The extracted variables and outcomes were synthesized through pooled analyses. RESULTS Eight articles with 51 patients who underwent endovascular chimney technique for aortic arch pathologies met the inclusion criteria. Chimney grafts were deployed in innominate (n = 11), left common carotid (n = 32), and left subclavian (n = 12) arteries. Single-stent chimney in the deployed artery was used in 37 patients, whereas double-stent chimney was utilized in 14 patients. The overall technical success rate was 90.2%. The overall perioperative mortality and morbidity were 5.9% and 13.7%, respectively. The stroke rate was 7.8%, and the fatal stroke rate accounted for 50%. The rates of primary early endoleaks and type-Ia endoleaks were 21.6% and 11.8%, respectively. The overall late mortality and morbidity were 4.4% and 15.5%, respectively. Of 5 late endoleaks, no secondary type-Ia endoleak occurred. No studies had adequate follow-up to reliably evaluate the long-time durability. CONCLUSIONS Endovascular chimney technique is technically feasible with the high initial technical success rate and relatively favorable rates of perioperative outcomes for aortic arch pathologies. However, further establishment of the role of endovascular chimney necessitates the accumulation of more cases and comparative study with other management as well as prolonged follow-up.

The single-centre experience of the supra-arch chimney technique in endovascular repair of type B aortic dissections.

OBJECTIVES We summarised the data performed at our centre to evaluate the feasibility of the chimney technique in type B aortic dissections (ADs) with supra-aortic vessel involvement. METHODS From September 2006 to December 2011, 34 thoracic endovascular aortic repairs (TEVARs) for ADs were performed combined with reconstruction of the arch branches with chimney stents (innominate artery, IA, n = 3; left common carotid artery, LCCA, n = 8; left subclavian artery, LSA, n = 23). Indications for these chimney stents included an inadequate proximal landing zone (<1.5 cm); high surgical-risk patients who are not suitable for open repair or hybrid procedures; and emergent endovascular repair of ADs. The series consisted of 13 acute, 12 sub-acute and 9 chronic cases. The right common carotid-left common carotid-left subclavian artery bypasses were performed in the IA chimney cases to reserve an adequate cerebral perfusion from the LCCA and left vertebral artery, while the left common carotid-left subclavian artery bypasses were performed in the cases having dominant left vertebral arteries. All the TEVARs, chimney stents and bypasses were performed as a single stage. Follow-ups were performed at 3, 6 and 12 months, and yearly thereafter. RESULTS Endografts were deployed in Zone 0 (n = 3, 9%), Zone 1 (n = 8, 24%) and Zone 2 (n = 23, 67%). Twenty-five (74%) balloon-expandable and 9 (26%) self-expanding stents were used, of which seven (21%) were covered and 27 (79%) were bare stents. The technical success rate was 82% (28/34). Immediate type I endoleaks were observed in five patients (5/34, 15%), all of which underwent bare chimney-stent repairs. Three self-expanding chimney stents were compressed by endografts and another balloon expandable stent was deployed inside the first one. Five patients underwent surgical bypasses (RCCA-LCCA-LSA, n = 3; LCCA-LSA, n = 2). Perioperative morbidity included one ST-elevation myocardial infarction. No perioperative death or stroke was observed. The mean follow-up was 16.3 months (range, 3-60 months). Primary patency was maintained in all the chimney stents as well as the surgical bypasses. No stent fracture or recurrent chimney-related endoleak was observed during the follow-up period. CONCLUSIONS In repairs for type B ADs, the chimney technique provides a minimally invasive way of preserving flow to the arch branches combined with a favourable mid-term outcome. The bare stents seemed to be related to a higher probability of the immediate type I endoleaks. A balloon-expandable stent should be regarded as the first choice due to its greater radial strength.

Hyperhomocysteinaemia is an independent risk factor of abdominal aortic aneurysm in a Chinese Han population

The associations between hyperhomocysteinaemia (HHcy), methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, and abdominal aortic aneurysm (AAA) remain controversial, with only few studies focused on these associations within the Chinese population. We performed subgroup and interaction analyses in a Chinese Han population to investigate these associations. In all, 155 AAA patients and 310 control subjects were evaluated for serum total homocysteine levels and MTHFR C677T polymorphisms. Multiple logistic regression models were used to evaluate the aforementioned associations. Interaction and stratified analyses were conducted according to age, sex, smoking status, drinking status, and chronic disease histories. The multiple logistic analyses showed a significant association between HHcy and AAA but no significant association between MTHFR C677T polymorphism and AAA. The interaction analysis showed that age and peripheral arterial disease played an interactive role in the association between HHcy and AAA, while drinking status played an interactive role in the association between MTHFR C677T polymorphism and AAA. In conclusion, HHcy is an independent risk factor of AAA in a Chinese Han population, especially in the elderly and peripheral arterial disease subgroups. Longitudinal studies and clinical trials aimed to reduce homocysteine levels are warranted to assess the causal nature of these relationships

Multibranched Stent-Grafts for the Treatment of Thoracoabdominal Aortic Aneurysms A Systematic Review and Meta-analysis

Purpose: To evaluate the available literature on endovascular repair of thoracoabdominal (TAAA) and pararenal aortic aneurysms (PRAA) using multibranched stent-grafts. Methods: MEDLINE, EMBASE, and Cochrane databases were searched between January 2001 and June 2015 to identify articles related to the use of multibranched stent-grafts for the treatment of TAAA and PRAA. Articles with <4 cases and those on juxtarenal aortic aneurysms were excluded. Meta-analyses were conducted to evaluate 30-day mortality, all-cause mortality, spinal cord ischemia, renal insufficiency, endoleak, target vessel patency, and reintervention. Of 370 articles screened, only 4 articles encompassing 185 patients (mean age 71.1 years; 137 men) were aligned with the inclusion criteria. There were 23 PRAAs; the mean aneurysm diameter was 64.5 mm. The Crawford TAAA classification was 10 type I, 47 type II, 37 type III, 58 type IV, and 9 type V; there was 1 Stanford type B dissection in association with a large TAAA. Results of the meta-analyses are reported as proportions and 95% confidence interval (CI). Results: Pooled analysis indicated a technical success rate of 98.9%. As study heterogeneity was significant, random effects models were used for meta-analysis. The rate for 30-day mortality was 9% (95% CI 3% to 19%), for all-cause mortality 27% (95% CI 17% to 38%), endoleaks 10% (95% CI 1% to 25%), target vessel patency 98% (95% CI 95% to 99%), SCI 17% (95% CI 1% to 26%), irreversible SCI 6% (95% CI 3% to 10%), renal insufficiency 15% (95% CI 0.8% to 41%), and reinterventions 21% (95% CI 4% to 47%). Conclusion: Use of multibranched stent-grafts in the treatment of TAAAs and PRAAs appears to be feasible and safe based on satisfactory early outcomes in the limited literature available to date. Long-term surveillance and further studies are essential to determine the durability of this technique.

Association between diabetes and prevalence and growth rate of abdominal aortic aneurysms: A meta-analysis☆

BACKGROUND Although the prevalence of abdominal aortic aneurysm (AAA) was lower in diabetes, the relationship between diabetes and AAA prevalence remains unclear. In this meta-analysis, we sought to clarify the effect of diabetes on prevalence and growth rate (GR) of AAA. METHODS We searched PubMed, Web of Science, Scopus and Cochrane databases. Articles reporting the AAA prevalence in diabetic patients and diabetic effects in GR of AAA were included. RESULTS Forty-nine studies on AAA prevalence in diabetics and thirteen studies on effect of diabetes in GR of AAA were included for meta-analysis. A strongly negative association was found between diabetes and AAA prevalence in population based screening (odds ratio [OR]adjusted: 0.66; 95% confidence interval [CI]: 0.58-0.75) and prospective studies (ORadjusted: 0.52; 95% CI: 0.43-0.63), but not in case-control studies (ORadjusted: 0.48; 95% CI: 0.20-1.15). Similar association was found in North American (ORadjusted: 0.62; 95% CI 0.54-0.71) and European (ORadjusted: 0.45; 95% CI 0.33-0.62) studies. The strongly negative association remained consistent after stratification by time of data collection (up to -1995 [ORadjusted: 0.65; 95% CI: 0.53-0.80], 1996-2005 [ORadjusted: 0.61; 95% CI: 0.47-0.78], 2006 and beyond- [ORadjusted: 0.67; 95% CI: 0.53-0.85], and data collection time >10years [ORadjusted: OR: 0.44; 95% CI 0.34-0.58]). The annual mean diabetic effect on AAA GR was -0.60mm/y (95% CI: -0.76 - -0.43). CONCLUSION Diabetes was strongly and negatively associated with AAA prevalence regardless of study type, geography and time of data collection, as well as negative impact of diabetes on GR of AAA.

Association of polymorphisms on chromosome 9p21.3 region with increased susceptibility of abdominal aortic aneurysm in a Chinese Han population

OBJECTIVE Several studies have reported that polymorphisms on chromosome 9p21.3, near the CDKN2A/2B gene, are strongly associated with increased susceptibility to abdominal aortic aneurysm (AAA). However, no convincing data has been reported on a relationship between AAA and these variants in the Chinese Han population. The aim of this study was to evaluate the role of rs10757278 and rs1333049 in determining genetic susceptibility to AAA. METHODS A total of 155 AAA patients and 310 controls, comparable in age and gender, were enrolled in this study. DNA samples were genotyped for rs10757278 and rs1333049 using the MassArray system. The association between these two single nucleotide polymorphisms and AAAs was tested using multivariate logistic regression. Stratified analysis was also performed by clinical and laboratory features. RESULTS Single nucleotide polymorphisms rs10757278 and rs1333049 were significantly associated with increased risk of AAA. The frequencies of rs10757278-G and rs1333049-C in AAA patients were significantly higher than in control subjects (odds ratio [OR], 1.53; 95% confidence interval [CI], 1.11-2.11; P = .01, and OR, 1.48; 95% CI, 1.07-2.05; P = .02). Multiple logistic regression analysis indicated that, after adjusting for smoking habits, drinking habits, and histories of other chronic diseases, homozygosity of the risk allele for rs10758278-G and rs1333049-C also increased the likelihood of AAA (OR, 2.31; 95% CI, 1.22-4.36, and OR, 2.14; 95% CI, 1.13-4.05). The frequency of the GC haplotype was significantly higher in AAA patients than in control subjects (OR, 1.44; P = .038). Stratification analysis of clinical and laboratory features revealed no association between polymorphisms and aortic diameters in AAA patients. There was a significantly high frequency of the rs10757278 GG genotype in AAA patients with high serum total homocysteine compared with those control subjects with high serum total homocysteine (OR, 2.71; 95% CI, 1.12-6.58; P = .03) indicating that the genotype GG of rs10757278 might interact with the homocysteine biological pathway to stimulate the presence of AAA. CONCLUSIONS Present data demonstrate that rs10757278 and rs1333049 on chromosome 9p21.3 are significantly associated with increased risk of AAA in the Chinese population and emphasize the need to further study the role of these markers in AAA.

Open and Endovascular Repair of Primary Mycotic Aortic Aneurysms: A 10-Year Single-Center Experience

Purpose To report early and midterm outcomes after open or endovascular repair of primary mycotic aortic aneurysms treated over a 10-year period in a single center. Methods The records of all 12 patients (10 men; 72.9 years, range 59–83) treated for primary mycotic aortic aneurysms from September 2001 to December 2010 were retrospectively reviewed. The aneurysms were located in the abdominal aorta in 10 cases and in the thoracic aorta in 2. Preoperative signs of infection, such as leukocytosis or elevated C-reactive protein, were found in all patients, and fever was apparent in 7. Three patients had primary open surgery with extensive debridement and extra-anatomical bypass, while 9 patients underwent endovascular aneurysm repair. At the time of operation, 10 mycotic aneurysms were already ruptured. All patients were prescribed lifelong antibiotics after discharge. Results Positive microbial cultures were found in 8 patients, including Salmonella species in 2, S. aureus in 3, E. coli in 1, and Streptococcus in 1. Mean follow-up was 29.9 months (range 1–98). Five patients took lifelong oral antibiotics after discharge with a mean medication duration of 17 months (range 1–65). Two of the 3 open surgery patients died (1 early). In the 9 endovascular repair patients, there was no early mortality, but 1 patient died at 6 months of an unknown cause. Additionally, 6 patients had a late relapse and underwent either secondary open surgical debridement (n=2) or computed tomography–guided drainage and antibiotic flush; 3 of the 6 died. Conclusion Endovascular aneurysm repair is a reasonable short-term management for patients with hemodynamic instability or high surgical risk. However, the late relapse rate after endovascular repair was very high in this series, despite adjunctive drainage and aggressive antibiotic treatment.

The value of a new image classification system for planning treatment and prognosis of spontaneous isolated superior mesenteric artery dissection

Objective To aid diagnosis of spontaneous isolated superior mesenteric artery dissection and planning management, we investigated the role of classification of features as observed on computed tomography angiography images. Methods A retrospective study was conducted, comprising computed tomography angiography images and clinical data of 28 consecutive patients with spontaneous isolated superior mesenteric artery dissection. Based on the computed tomography angiography images, a new classification for spontaneous isolated superior mesenteric artery dissection was proposed. Patients with intestinal ischemia not relieved or worsened after 10 days of conservative treatment underwent surgery or stenting. All patients were followed up with computed tomography angiography. Results Spontaneous isolated superior mesenteric artery dissection was categorized into five types (I–V). Type III was further divided into subtypes IIIa–IIIc. Spontaneous isolated superior mesenteric artery dissection IIIa and IV typified nine (32.1%) and seven (25%) patients, respectively. Six (21.4%) patients had aortic or branch artery abnormalities and 21 (78%) showed prior intestinal ischemia. Four (14.3%) patients had intestinal ischemia and underwent surgery or stenting. Conclusions Spontaneous isolated superior mesenteric artery dissection type IIIa is more likely to occur than other types. Long-term computed tomography angiography follow-up is valuable for determining treatment strategy for spontaneous isolated superior mesenteric artery dissection. Conservative therapy with anticoagulants is recommended for five days, and surgery or stenting should be considered if symptoms of intestinal ischemia are not relieved. Stent implantation provides relatively satisfactory mid-term outcome for true lumen construction of the superior mesenteric artery.

Renal Artery Aneurysm Treatment With Stent Plus Coil Embolization

Renal artery aneurysm (RAA) is a rare event that may cause life-threatening rupture or renal function-threatening embolization. We report here a case of eccentric RAA involving the left upper pole renal artery and its three bifurcations, which was treated by stent plus coil embolization; the patient exhibited no renal insufficiency at 1-year follow-up. This endovascular strategy, therefore, may be applicable to this anatomical variant RAA.

Novel-Designed Iliac Branch Stent Graft for Internal Iliac Artery Reconstruction during Aneurysm Repair

BACKGROUND Iliac branch stent grafts (IBSGs) have been used for internal iliac artery preservation during aneurysm repair. However, current available branch iliac stent grafts used in Western countries are not suitable for many patients in Asia because of shorter common iliac arteries (CIA). The aim of this study was to evaluate the efficacy of a novel-designed IBSG in preservation of internal iliac artery during endovascular aneurysm repair in Chinese. METHODS Eleven male patients (range, aged 65-80 years) underwent endovascular repair with 15 IBSGs, including 4 bilateral repairs between January 2011 and December 2012. The median abdominal aortic aneurysm diameter was 50 mm and the common iliac diameter was 38 mm. All patients received computed tomography angiography (CTA) before discharge and every 3 months afterward. RESULTS The stent-graft deployment was technically successful in all cases. Seven of the 11 patients had uneventful procedures and the rest 4 complicated with fever, renal insufficiency, and groin hematoma. The median length of hospitalization was 7 days. Perioperative mortality was zero. Follow-up documented that 1 patient died at 14 months after surgery because of an unrelated cause. Two patients were found to have a type I and III endoleak, respectively, then successful treatments with internal iliac artery extension stent grafts were applied at 6 months. The overall primary patency was 86.7%. Follow-up CTA showed aneurysm shrinkage in all patients. CONCLUSIONS These novel-designed IBSGs are safe and effective in preservation of internal iliac artery. It provides an alternative option for endovascular repair of the iliac aneurysms with short CIA, which is more common in Asian population.