Circulating Interleukin-6 and CD16 positive monocytes increase following angioplasty of an arteriovenous fistula.

Arteriovenous fistulas are the ideal form of vascular access that allows provision of haemodialysis. Stenotic lesions caused by neointimal hyperplasia commonly occur resulting in patients requiring a fistuloplasty. This is effective but there is a high recurrence rate. We sought to investigate the effects of a fistuloplasty on monocyte populations. Blood samples were taken from patients before and after their fistuloplasty procedure. Samples were analysed using flow cytometry, ELISA and Luminex assays. Univariate cox regression was carried out to investigate associations with post fistuloplasty patency. At 1-2 days post fistuloplasty, the proportion of classical (CD14++CD16-) monocytes decreased (p < 0.001), whilst intermediate (CD14++CD16+) and non-classical (CD14+CD16+) monocytes increased (both p < 0.01) in a cohort of 20 patients. A time course study carried out in 5 patients showed that this was due to an increase in absolute numbers of non-classical and intermediate monocytes. Higher levels of non-classical monocytes pre-fistuloplasty were associated with an increased risk for patency loss (p < 0.05). We measured 41 soluble factors in plasma samples taken before a fistuloplasty in 54 patients, with paired post-fistuloplasty samples (1-2 days) available in 30 patients. After correcting for false discovery, the only factor with a significant change in level was IL-6 (P = 0.0003, q = 0.0124). In a further time-course study in 6 patients, peak level of IL-6 occurred 2-3 h post fistuloplasty. This study demonstrates that there is a systemic inflammatory response to the fistuloplasty procedure and that monocyte subsets and IL-6 may be important in the pathophysiology of restenosis.

Association of early failure of arteriovenous fistula with mortality in hemodialysis patients.

Arteriovenous fistula (AVF) is prone to early dysfunction and relates to poor outcome. However, little is known about the role of early AVF dysfunction as an independent risk factor for death in hemodialysis patients. A retrospective cohort study was performed using data of patients who underwent initial AVF surgery at a single institution. Demographic, clinical, biochemistry and AVF parameters were extracted from the electronic records, and the association between these variables and mortality was analyzed by Cox proportional hazards model. A total of 501 patients on hemodialysis (63.4 ± 12.7 years, 57.3% male) were included, and the median observation period was 3.66 years. In multivariate analysis, early failure of AVF (hazard ratio (95% confidence interval): 1.54 (1.06-2.24); p = 0.023) was associated with overall mortality but not cardiovascular mortality. Other identified predictors of overall mortality included older age, peripheral artery disease (PAD), cardiomegaly, higher white blood cell (WBC) count and corrected calcium level, and lower total cholesterol level, while predictors of cardiovascular mortality included older age, coronary artery disease (CAD), PAD and lower hemoglobin level. In conclusion, patients with early AVF failure were associated with increased risk of overall mortality.

Morbidity and mortality associated with sequential flow reduction embolization technique of cerebral arteriovenous malformations using n-butyl cyanoacrylate.

BACKGROUND: Endovascular embolization of cerebral arteriovenous malformations (AVM) with liquid n-butyl cyanoacrylate (n-BCA) serves multiple purposes including AVM occlusion and flow reduction in preparation for other treatment modalities. The objective was to study the clinical, structural, and angiographic factors affecting complications associated with AVM treatment by sequential n-BCA embolizations for nidal occlusion versus quantitative flow reduction in preparation for surgical resection or radiosurgery. METHODS: We performed a retrospective review of all patients who underwent endovascular embolization of cerebral AVM at our institution between 1998 and 2019, during which time the technique of traditional embolization evolved to a strategy of targeted sequential flow reduction guided by serial flow imaging based on quantitative magnetic resonance angiography, in conjunction with a shift away from nidal penetration. RESULTS: Among 251 patients, 47.8% of patients presented with ruptured AVM. On average, each patient underwent 2.4 embolizations, for a total of 613 sessions. Major morbidity related to embolization occurred in 18 (7.2%) patients, but this occurred disproportionately in the traditional embolization strategy (n=16, 8%) in contrast with the flow-targeting strategy (n=2, 3.8%). Four patients (1.6%) died in the overall group, and these all occurred with the traditional embolization strategy (2% of 199 patients); no deaths occurred in the flow-targeting strategy (n=52). CONCLUSION: Embolization with n-BCA targeted to sequential flow reduction and feeder occlusion with limited nidal penetration prior to definitive surgical or radiosurgical treatment can be safely performed with low overall morbidity and mortality.

Outcomes of Surgical and Endovascular Treatment for Arterial Lesions in Intravenous Drug Abusers.

BACKGROUND: The objective of this study is to report an 18-year single-center experience in the surgical and endovascular treatment of arterial complications due to self-injection in drug abuser patients. METHODS: This retrospective single-center study was conducted analyzing a prospectively collected database including all endovascular or surgical procedures performed from January 2007 to December 2019 for any arterial complication due to self-injection in drug abuser patient. Collected data were patient demographic and comorbidity, site and type of arterial lesion (pseudoaneurysm [PA], arteriovenous fistula [AVF]), signs of systemic or local infection, and procedural data (endovascular/surgical treatment). End points were rate of postoperative complications, reintervention rate, limb salvage, and patients' early and long-term survival. RESULTS: In 11 patients (median age 36 years, range 27-47; male 73%), 13 arterial lesions were treated: 10 (77%) PA, 2 (15%) PA associated with AVF, and 1 (8%) isolated AVF. Arterial lesion involved common femoral artery in 5 (38%), superficial femoral artery in 4 (31%), profunda femoral artery in 1 (8%), brachial artery in 2 (15%), and subclavian artery in 1 (8%). Signs of infections were present in 9 of the 13 cases (69%). The treatment was surgical in 11 (85%) cases: 7 interposition graft (6 great saphenous vein, 1 arterial cryopreserved homograft), 2 direct reconstruction, 1 patch plasty with pericardium bovine patch, and 1 arterial ligation. Endovascular treatment was performed in 2 cases: 1 noninfected PA of the superficial femoral artery, and 1 55-mm PA of the postvertebral segment of the right subclavian artery with clinical sign of hemodynamic instability. At 1 month, postoperative complication rate was 8% (one lower limb claudication after superficial femoral artery ligation). Reintervention rate was 8% (interposition graft rupture for repeated self-injections). Limb salvage and patient survival were both 100%. Median follow-up was 5 years (range 1 month to 11.3 years); surgical group: median 8.2 years (range 2 months to 11.3 years); endovascular group: median 3.5 months (range 1-6). During follow-up, neither complications nor reinterventions occurred, and limb salvage was 100% for both groups. At 2, 4, and 6 years, overall estimated patient survival was 91%, 81%, and 81%, respectively, with no procedure-related death. CONCLUSIONS: After surgical or endovascular management of arterial lesions due to self-injection in drug abuser patients, complications occur mainly in the postoperative period. During follow-up, the surgical procedures have low rate of complications, reinterventions, and procedure-related mortality, whereas for the endovascular treatment the mid-term outcomes remain unknown.

Medical management with interventional therapy versus medical management alone for unruptured brain arteriovenous malformations (ARUBA): final follow-up of a multicentre, non-blinded, randomised controlled trial.

BACKGROUND: In A Randomized trial of Unruptured Brain Arteriovenous malformations (ARUBA), randomisation was halted at a mean follow-up of 33·3 months after a prespecified interim analysis showed that medical management alone was superior to the combination of medical management and interventional therapy in preventing symptomatic stroke or death. We aimed to study whether these differences persisted through 5-years' follow-up. METHODS: ARUBA was a non-blinded, randomised trial done at 39 clinical centres in nine countries. Adults (age ≥18 years) diagnosed with an unruptured brain arteriovenous malformation, who had never undergone interventional therapy, and were considered by participating clinical centres to be suitable for intervention to eradicate the lesion, were eligible for inclusion. Patients were randomly assigned (1:1) by a web-based data collection system, stratified by clinical centre in a random permuted block design with block sizes of two, four, and six, to medical management alone or with interventional therapy (neurosurgery, embolisation, or stereotactic radiotherapy, alone or in any combination, sequence, or number). Although patients and investigators at a given centre were not masked to treatment assignment, investigators at other centres and those in the clinical coordinating centre were not informed of assignment or outcomes at any of the centres. The primary outcome was time to death or symptomatic stroke confirmed by imaging, assessed by a neurologist at each centre not involved in the management of participants' care, and monitored by an independent committee using an adaptive approach with interim analyses. Enrolment began on April 4, 2007, and was halted on April 15, 2013, after which follow-up continued until July 15, 2015. All analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, NCT00389181. FINDINGS: Of 1740 patients screened, 226 were randomly assigned to medical management alone (n=110) or medical management plus interventional therapy (n=116). During a mean follow-up of 50·4 months (SD 22·9), the incidence of death or symptomatic stroke was lower with medical management alone (15 of 110, 3·39 per 100 patient-years) than with medical management with interventional therapy (41 of 116, 12·32 per 100 patient-years; hazard ratio 0·31, 95% CI 0·17 to 0·56). Two patients in the medical management group and four in the interventional therapy group (two attributed to intervention) died during follow-up. Adverse events were observed less often in patients allocated to medical management compared with interventional therapy (283 vs 369; 58·97 vs 78·73 per 100 patient-years; risk difference -19·76, 95% CI -30·33 to -9·19). INTERPRETATION: After extended follow-up, ARUBA showed that medical management alone remained superior to interventional therapy for the prevention of death or symptomatic stroke in patients with an unruptured brain arteriovenous malformation. The data concerning the disparity in outcomes should affect standard specialist practice and the information presented to patients. The even longer-term risks and differences between the two therapeutic approaches remains uncertain. FUNDING: National Institute of Neurological Disorders and Stroke for the randomisation phase and Vital Projects Fund for the follow-up phase.

Risk of Complications and Survival of Patients Dialyzed with Permanent Catheters.

Background and Objectives: An increase in the incidence of end-stage renal disease (ESRD) is associated with the need for a wider use of vascular access. Although arteriovenous (A-V) fistula is a preferred form of vascular access, for various reasons, permanent catheters are implanted in many patients. Materials and Methods: A retrospective analysis of clinical data was carried out in 398 patients (204 women) who in 2010-2016 were subjected to permanent dialysis catheters implantation as first vascular access or following A-V fistula dysfunction. The factors influencing the risk of complications related to vascular access and mortality were evaluated and the comparison of the group of patients with permanent catheter implantation after A-V fistula dysfunction with patients with first-time catheter implantation was carried out. Results: The population of 398 people with ESRD with mean age of 68.73 ± 13.26 years had a total of 495 permanent catheters implanted. In 129 (32.6%) patients, catheters were implanted after dysfunction of a previously formed dialysis fistula. An upward trend was recorded in the number of permanent catheters implanted in relation to A-V fistulas. Ninety-two infectious complications (23.1%) occurred in the study population in 65 patients (16.3%). Multivariate analysis showed that permanent catheters were more often used as the first vascular access option in elderly patients and cancer patients. Mortality in the mean 1.38 ± 1.17 years (min 0.0, max 6.70 years) follow-up period amounted to 50%. Older age and atherosclerosis were the main risk factors for mortality. Patients with dialysis fistula formed before the catheter implantation had a longer lifetime compared to the group in which the catheter was the first access. Conclusion: The use of permanent catheters for dialysis therapy is associated with a relatively high incidence of complications and low long-term survival. The main factors determining long-term survival were age and atherosclerosis. Better prognosis was demonstrated in patients after the use of A-V fistula as the first vascular access option.

The Unique Features and Outcomes of Microsurgically Resected Cerebellar Arteriovenous Malformations.

BACKGROUND: Cerebellar arteriovenous malformations (CAVMs) are challenging to treat given their close proximity to the brain stem, greater propensity for rupture, and greater rates of morbidity and mortality than other brain arteriovenous malformations. The present investigation sought to describe and characterize the features of these rare and unique lesions. METHODS: A retrospective review of CAVM cases treated at 2 tertiary medical centers was performed. Patients surgically treated at institution 1 from September 1999 to February 2013 and institution 2 from October 2008 to October 2015 were included. RESULTS: A total of 120 patients had been treated. Of the 120 patients, 85 (70.8%) had initially presented with hemorrhage, 45 (37.5%) of whom experienced hemorrhage requiring emergent surgery. A favorable neurological outcome was observed in 76 patients (63.3%; modified Rankin Scale score <3). The perioperative mortality was 2.5% (n = 3). The long-term mortality rate was 7.5% (n = 9). The mean follow-up time was 1.82 years. On average, the patients with large CAVMs (≥3 cm; P ≤ 0.001), who had received embolization before surgery (P = 0.04), did not have an associated aneurysm (P ≤ 0.001), or had a residual CAVM after surgery (P = 0.008) were significantly younger. Female patients had fewer CAVMs with deep venous drainage (54.3% vs. 72.3%; P = 0.049), experienced decreased mortality (1.4% vs. 16.7%; P = 0.003), and were less likely to have worse neurological status after treatment (P = 0.003). CONCLUSIONS: CAVMs are rare lesions that exhibit unique disease characteristics. Although most patients will experience a favorable outcome, CAVMs frequently present with hemorrhage, result in high rates of morbidity and mortality, and characteristically differ depending on patient age and gender.

Stereotactic Radiosurgery for Pediatric Versus Adult Brain Arteriovenous Malformations.

Background and Purpose- The aim of this international, multicenter, retrospective matched cohort study is to directly compare the outcomes after stereotactic radiosurgery (SRS) for brain arteriovenous malformations (AVM) in pediatric versus adult patients. Methods- We performed a retrospective review of patients with AVM who underwent SRS at 8 institutions participating in the International Gamma Knife Research Foundation from 1987 to 2014. Patients were categorized into pediatric (<18 years of age) and adult (≥18 years of age) cohorts and matched in a 1:1 ratio using propensity scores. Favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes. Results- From a total of 2191 patients who were eligible for inclusion in the overall study cohort, 315 were selected for each of the matched cohorts. There were no significant differences between matched pediatric versus adult cohorts with respect to the rates of favorable outcome (59% versus 58%; P=0.936), AVM obliteration (62% versus 63%; P=0.934), post-SRS hemorrhage (9% versus 7%; P=0.298), radiological radiation-induced changes (26% versus 26%; P=0.837), symptomatic radiation-induced changes (7% versus 9%; P=0.383), or permanent radiation-induced changes (2% versus 3%; P=0.589). The all-cause mortality rate was significantly lower in the matched pediatric cohort (3% versus 10%; P=0.003). Conclusions- The outcomes after SRS for comparable AVMs in pediatric versus adult patients were not found to be appreciably different. SRS remains a reasonable treatment option for appropriately selected pediatric patients with AVM, who harbor a high cumulative lifetime hemorrhage risk. Age seems to be a poor predictor of AVM outcomes after SRS.

Primary and secondary arterial fistulas during chronic Q fever.

OBJECTIVE: After primary infection with Coxiella burnetii, patients may develop acute Q fever, which is a relatively mild disease. A small proportion of patients (1%-5%) develop chronic Q fever, which is accompanied by high mortality and can be manifested as infected arterial or aortic aneurysms or infected vascular prostheses. The disease can be complicated by arterial fistulas, which are often fatal if they are left untreated. We aimed to assess the cumulative incidence of arterial fistulas and mortality in patients with proven chronic Q fever. METHODS: In a retrospective, observational study, the cumulative incidence of arterial fistulas (aortoenteric, aortobronchial, aortovenous, or arteriocutaneous) in patients with proven chronic Q fever (according to the Dutch Chronic Q Fever Consensus Group criteria) was assessed. Proven chronic Q fever with a vascular focus of infection was defined as a confirmed mycotic aneurysm or infected prosthesis on imaging studies or positive result of serum polymerase chain reaction for C. burnetii in the presence of an arterial aneurysm or vascular prosthesis. RESULTS: Of 253 patients with proven chronic Q fever, 169 patients (67%) were diagnosed with a vascular focus of infection (42 of whom had a combined vascular focus and endocarditis). In total, 26 arterial fistulas were diagnosed in 25 patients (15% of patients with a vascular focus): aortoenteric (15), aortobronchial (2), aortocaval (4), and arteriocutaneous (5) fistulas (1 patient presented with both an aortocaval and an arteriocutaneous fistula). Chronic Q fever-related mortality was 60% for patients with and 21% for patients without arterial fistula (P < .0001). Primary fistulas accounted for 42% and secondary fistulas for 58%. Of patients who underwent surgical intervention for chronic Q fever-related fistula (n = 17), nine died of chronic Q fever-related causes (53%). Of patients who did not undergo any surgical intervention (n = 8), six died of chronic Q fever-related causes (75%). CONCLUSIONS: The proportion of patients with proven chronic Q fever developing primary or secondary arterial fistulas is high; 15% of patients with a vascular focus of infection develop an arterial fistula. This observation suggests that C. burnetii, the causative agent of Q fever, plays a role in the development of fistulas in these patients. Chronic Q fever-related mortality in patients with arterial fistula is very high, in both patients who undergo surgical intervention and patients who do not.

Does Advanced Age Affect the Outcomes of Stereotactic Radiosurgery for Cerebral Arteriovenous Malformation?

BACKGROUND: Stereotactic radiosurgery (SRS) is generally considered a minimally invasive treatment modality. However, definitive evidence of the efficacy of SRS in the elderly population is still not available. METHODS: The outcomes of 561 elderly and nonelderly patients who underwent SRS for AVM at our institution between 1990 and 2013 were reviewed, analyzed, and compared. Elderly patients were defined as those age ≥60 years at the time of SRS. RESULTS: The elderly cohort comprised 55 patients; the nonelderly cohort, 506. In the elderly cohort, the median age was 65 years, and the duration of follow-up was 91 months. The actuarial obliteration rates were 47% at 3 years, 70% at 4 years, and 76% at 5 years in the elderly cohort, and 57% at 3 years, 76% at 4 years, and 83% at 5 years in the nonelderly cohort. In the elderly cohort, the hemorrhage rates during the post-SRS latent phase were 5.2%/year in patients with hemorrhagic onset and 0%/year in those with nonhemorrhagic onset, and event-free survival (EFS) was 93% at 6 years and 89% at 12 years. The obliteration rate, mortality, and EFS rate were not significantly different between the 2 cohorts, whereas the rate of perifocal edema was significantly lower (P = 0.021) in the elderly cohort. The pre-SRS and post-SRS hemorrhage rates were slightly higher in the elderly cohort, albeit without statistical significance. CONCLUSIONS: Therapeutic effects and outcomes of SRS are similar in elderly and nonelderly patients. Treatment-related neurologic deficits are rare, and longer EFS can be expected.

Association between arteriovenous fistulae and hematomas in a dialysis center in the state of Rio Grande do Sul, Southern Brazil

Introduction: Chronic kidney disease (CKD) is characterized by slow, progressive, and irreversible loss of kidney function. CKD has become a serious public health issue because of its increasing morbidity and mortality rates. The present study aimed to investigate factors associated with hematomas caused by arteriovenous fistula (AVF) at a Renal Replacement Therapy Unit in the state of Rio Grande do Sul, southern Brazil. Methods: In this cross-sectional study, 72 patients with CKD aged 18 years or over, presenting with AVF, and undergoing three hemodialysis sessions per week were evaluated from June 2014 to March 2015. Prevalence ratios (PRs) with 95% confidence intervals (95% CIs) were estimated for identification of risk factors associated with AVF. P-values < 0.05 were considered significant. Results: Sex, age, self-reported skin color, educational level, hypertension, diabetes, nephrotic syndrome, congestive heart failure, and hepatitis C were not associated with hematoma formation (i.e., all estimated PRs had p-values > 0.05). The single factor associated with hematomas was AVF time shorter than 60 days (PR = 2.04; 95% CI: 1.28-3.27; p < 0.01). Conclusion: AVF maturation time was associated with higher prevalence of hematomas at the cannulation site. Therefore, AVF time should be given special attention in patients undergoing renal therapy at dialysis centers. (AU)

Clinical outcomes of early scheduled Fontan completion following Kawashima operation.

OBJECTIVES: This study reviewed late clinical features after Kawashima operation to confirm the impact of scheduled subsequent early Fontan completion. METHODS: Of the 17 consecutive patients who underwent the Kawashima operation between 1987 and 2010, 11 underwent the procedure as inter-stage palliation (scheduled Fontan group). Ten of these patients underwent subsequent early Fontan completion after a median interval of 0.6 years. The remaining 6 patients underwent the Kawashima operation initially as definitive surgery (non-scheduled group). Late Fontan completion was performed in 4 of these patients as salvage surgery to prevent progression of hypoxia after a median interval of 6.6 years. RESULTS: All patients completed follow-up; the mean follow-up period was 12 ± 7 years (range 0.6-28.2). Cumulative survival at 10 years was 66% in the non-scheduled group and 79% in the scheduled group (p = 0.66). Pulmonary arteriovenous malformations developed after Kawashima operation in all 4 patients without antegrade pulmonary blood flow in the non-scheduled group but in only 2 of 11 patients in the scheduled group, both of which completely resolved after Fontan completion. In the scheduled Fontan group, 3 patients developed venovenous malformations between the Fontan pathway and the pulmonary veins or atrium after Fontan completion. CONCLUSIONS: Issues related to pulmonary arteriovenous malformations after Kawashima operation resolved with early scheduled Fontan completion. However, data on long-term outcomes are limited and the risk of death continues throughout early life. For unsuitable Fontan candidates, the Kawashima operation with antegrade pulmonary blood flow may provide definitive palliation.

Serum sclerostin levels, arteriovenous fistula calcification and 2-years all-cause mortality in prevalent hemodialysis patients.

BACKGROUND: Bone and mineral abnormalities, and cardiovascular calcification are associated with increased cardiovascular mortality in patients with chronic kidney disease (CKD). Recent studies have implicated Wnt signaling pathway in the pathogenesis of bone metabolism and vascular calcification. Sclerostin is a soluble inhibitor of Wnt signaling pathway and has been shown to be associated with decreased bone turnover and vascular calcification in CKD patients. OBJECTIVES: The aim was to investigate whether the circulating levels of sclerostin are associated with all-cause mortality in prevalent hemodialysis patients. METHODS: Data are prospectively collected for 24 months for survival analysis in 350 prevalent hemodialysis patients. At baseline, serum sclerostin levels were measured and arteriovenous fistula calcification was detected by using a 64-detector computerized tomographic scanner. RESULTS: During the follow-up, 84 (24%) patients died. Patients who died had higher serum sclerostin levels. Kaplan-Meier curve revealed that patients with increasing tertiles of serum sclerostin levels at baseline, had a worse survival. In the multivariate Cox regression analysis age, albumin, and presence of arteriovenous fistula calcification, but not sclerostin levels, were found to be independent predictors of survival in maintenance hemodialysis patients. CONCLUSION: Further clinical studies with longer follow-up are needed to clarify the impact of serum sclerostin levels on morbidity and mortality of maintenance hemodialysis patients. CLINICAL TRIAL REGISTRATION NUMBER: The study was performed as a post hoc survival analysis of the patients involved in a single-center prospective trial investigating the association between serum sclerostin levels and arteriovenous fistula calcification and patency [Balci M, et al. Herz 2015;40:289-97] with a Clinicaltrials.gov number: NCT01382966.

Endovascular treatment of major abdominal arteriovenous fistulas: a systematic review.

PURPOSE: To review the different outcomes of the endovascular repair of major abdominal arteriovenous fistulas (AVFs). METHODS: An online systematic review of the literature was undertaken to identify all reported cases of endovascular repair of major AVFs, covering 9 major databases as well as relevant journals up to September 2013. Our own case was included. The primary outcome was technical success and mortality, the secondary outcome was the rate of complications and the operators' recommendations. RESULTS: Forty-eight articles were reviewed totaling a number of 54 patients including our own. The most common fistula site was the aortocaval segment. Aortic stent grafts were used in 78% of patients. Technical success was 94%. Intraoperative mortality was 0% with a 90-day mortality of 10%, half of which were not related to the primary pathology. Of the successful procedures, 12% of patients had major complications. One died before reintervention. All others had uneventful recoveries; 21% had minor complications treated conservatively. The majority of authors were in favor of this treatment modality.

Transarterial treatment of congenital renal arteriovenous fistulas.

OBJECTIVE: Congenital renal arteriovenous fistulas (CRAVF) represent a distinct clinical entity with characteristic hemodynamic and angiographic features. Treatment is warranted given potential for growth with renal and hemodynamic compromise. We report our experience in a rare series of treated symptomatic CRAVFs. METHODS: Over a 10-year period, patients treated for symptomatic CRAVFs (no history of predisposing renal pathology, instrumentation, neoplasm, or trauma) were retrospectively investigated for clinical presentation, imaging features, treatment outcomes, and complications. Technical success included delivery of embolic agent with complete obliteration of fistula. Clinical success included resolution of symptoms and freedom from recurrence and/or reintervention. Renal parenchymal loss was estimated by postembolization angiography and categorized as 0%, <25%, 25%-50%, or >50%. RESULTS: Twenty-five patients were referred with a presumptive diagnosis of intraparenchymal renal artery aneurysms. Of these, 10 had true intrarenal aneurysms, three had angiomyolipomas, and 12 had CRAVFs (mean age, 54; range, 29-71 years; eight women). Presenting symptoms included hematuria (eight gross, eight microscopic), refractory hypertension (diastolic blood pressure ≥ 90 mm Hg despite three or more medications; n = 6), flank pain (n = 8), high-output state (HOS; featuring tachycardia and jugular venous distention; n = 3), and flank bruit (n = 1). Defining angiographic features included a high-flow AVF fed by a single, enlarged intrarenal branch shunting into an aneurismal draining vein, occasionally featuring a calcified rim (four patients). All patients underwent transarterial embolization with coils (n = 5), coils and n-butylcyanoacrylate (n = 3), detachable balloons (n = 2), or Amplatzer plugs (n = 2). Technical success was 100%. Hematuria, tachycardia, jugular venous distension, pain, and bruit resolved in all. Hypertension improved in four of six patients (required less than three medications postembolization). Complications included postembolization syndrome in nine patients. Parenchymal loss was limited to <25% and observed in five patients without development of acute kidney injury or worsening hypertension. There were no recurrences or reinterventions at a mean follow-up of 55 months (range, 5-96 months). There was one death at 8 years follow-up from intercurrent coronary disease in a patient without high-output state. CONCLUSIONS: With greater awareness and accurate diagnosis, effective and durable transarterial treatment of CRAVFs can be safely performed.

Systematic review and meta-analysis of open surgical and endovascular management of thoracic outlet vascular injuries.

BACKGROUND: Junctional vascular trauma such as that at the thoracic outlet poses particular challenges in surgical management. The use of endovascular techniques for such injuries is attractive as repair may be facilitated without the need for thoracotomy; however, the utility of such techniques is currently based on opinion, small retrospective series, and literature reviews of narrative and not systematic quality. The objective of this study is to provide a complete and systematic analysis of the literature pertaining to open surgery (OS) and endovascular management (EM) of thoracic outlet vascular injuries. METHODS: An electronic search using the MEDLINE, Embase, Cochrane Library, Science Citation Index, and LILACS databases was performed for articles published from 1947 to November 2011. The review conformed to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement standards. Prospective studies and retrospective cohorts of more than 10 patients were included. The primary outcome was all-cause mortality. RESULTS: One prospective noncomparative study and 73 retrospective series met the inclusion criteria. There were no randomized studies. All studies were at high risk of bias. Fifteen studies described outcomes for both OS and EM (549 patients). The majority of these studies described EM for traumatic arteriovenous fistulas or false aneurysms in stable patients. Direct comparison between OS and EM was possible in only three studies (comprising 23 OS and 25 EM patients), which showed no difference in all-cause mortality (odds ratio, 0.67; 95% confidence interval [CI], 0.11-4.05), but a shorter operating time with EM (mean difference = 58.34 minutes; 95% CI, 17.82-98.85). These three series included successful EM of unstable patients and those with vessel transection. There were 55 studies describing only OS (2057 patients) with a pooled mortality rate of 12.4% (95% CI, 9.9%-15.2%). Four studies described only EM (101 patients) with a pooled mortality rate of 26% (95% CI, 8%-51%), but these represented a distinct subgroup of cases (mainly iatrogenic injuries in older patients). CONCLUSIONS: The current evidence is weak and fails to show superiority of one modality over the other. EM is currently used primarily in highly selected cases, but there are reports of a broader applicability in trauma. High-quality randomized studies or large-scale registry data are needed to further comment on the relative merits or disadvantages of EM in comparison to OS.

Late outcome of repair of congenital coronary artery fistulas--a word of caution.

OBJECTIVES: We reviewed our experience with repair of congenital coronary artery fistulas. METHODS: From June 1983 to December 2009, 46 patients (median age, 59 years; range, 1-84 years) underwent surgical repair. The presenting symptoms included angina in 16 patients (35%), congestive heart failure in 11 (24%), and bacterial endocarditis in 5 (11%). Preoperatively, 9 patients (20%) had at least moderate tricuspid regurgitation. Coronary artery dominance was right in 38 patients (83%). Coronary artery aneurysms were found in 8 patients (17%). The most common pattern was right coronary artery-to-coronary sinus fistula (18 patients, 39%); 11 patients had (23%) more than 1 fistula. One patient had undergone previous coil embolization. RESULTS: Cardiopulmonary bypass was used in 39 patients (85%), with extracardiac and intracardiac repair performed in 30 (65%) and 16 (35%), respectively. The most common associated procedures were coronary artery bypass in 13 patients (28%). Early mortality occurred in 1 patient (2%). Postoperative myocardial infarction occurred in 5 patients (11%); 4 of these patients underwent simple ligation or division of their fistulas. The mean follow-up was 6 ± 5.8 years (maximum, 22 years). Late mortality occurred in 11 patients (24%). Two patients underwent reoperation for severe tricuspid regurgitation. Survival was significantly reduced compared with the age- and gender-matched population (P = .03). Residual fistulas were detected in 3 patients (6%), with no reintervention needed. CONCLUSIONS: Perioperative myocardial infarction is an important complication of ligation of coronary artery fistulas and can contribute to reduced late survival. The tricuspid valve should be evaluated carefully at repair because of the relatively high rate of residual regurgitation in survivors.

Aortocaval fistula formation due to ruptured abdominal aortic aneurysms: a 12-year series.

This study reports on the frequency and management of aortocaval fistulas (ACFs) in our department between 1998 and 2009. Overall frequency of ACFs among ruptured abdominal aortic aneurysms was 5.5%. Patients presented with low back pain (92.8%), abdominal tenderness (78.6%), hemorrhagic shock (28.6%), congestive heart failure (21.4%), dyspnea (42.8%), and palpitations (57.1%). The most reliable clinical sign was the presence of palpable pulsating abdominal mass (92.8%). Other clinical findings included increased central venous pressure (21.4%), lower extremity edema (71.4%), hematuria (21.4%), and scrotal edema (14.3%). Diagnosis was established preoperatively in 85.7% and intraoperatively in 14.3% of cases. Surgery was successful in promptly improving clinical signs and symptoms. Mortality rate was 7.1%. After a mean follow-up of 18.5 months, all surviving patients remained free from complications. In conclusion, ACFs represent a life-threatening emergency for vascular surgeons but can be successfully managed.

Paradoxical pulmonary embolism with spontaneous aortocaval fistula.

BACKGROUND: Paradoxical pulmonary embolisms are uncommon emergencies and can occur as a consequence of an aortocaval fistula due to unrecognized dislodgement of thrombus from aortic sac into pulmonary circulation. This study reviewed current literature and therapeutic options in this emergency condition requiring prompt management and repair. METHODS: Literature was systematically searched for paradoxical pulmonary embolism associated with aortocaval rupture. RESULTS: Eight published cases were identified. However, many other paradoxical pulmonary emboli could have remained undiagnosed due to challenging clinical presentation. Symptoms of high-output cardiac failure and respiratory distress in the presence of large aortoiliac aneurysm and venous hypertension are findings of a possible major abdominal arteriovenous fistula with paradoxical pulmonary embolism. Successful treatment depends on prevention of new embolism and proper management of perioperative hemodynamics and massive bleeding during fistula repair. Endovascular procedures have been recently used as useful tools in this field. Cava filter placement may be a first step to prevent further thrombus dislodgements during aortocaval repair. Immediate subsequent aortic stent-grafting can allow repair of aortocaval communication and exclusion of the abdominal aortic aneurysm from circulation with successful reversal of altered hemodynamic features. However, experience (especially in the long-term) is limited. CONCLUSIONS: Paradoxical pulmonary embolism from aortocaval fistula represents an extremely rare but true clinical emergency with high fatality rate. Recent advances in diagnostic technology and endovascular techniques can substantially improve outcomes of the disease. Clinical competence in early detection and diagnosis is essential for appropriate emergent management.

Twenty years of experience in the treatment of spontaneous aorto-venous fistulas in a developing country.

BACKGROUND: One of the rare forms of abdominal aortic aneurysm (AAA) rupture is the rupture into great abdominal veins such as the inferior vein cava (IVC), the iliac veins, or the left renal vein, with the formation of direct or indirect aorto-caval fistula (ACF). The purpose of the present study was to summarize 20 years of experience at a single referral center for vascular surgery in a developing country, and to discuss the clinical presentation, diagnosis, treatment options, and outcome of patients with spontaneous aorto-venous fistulas (AVF) caused by ruptured aortic aneurysms. MATERIALS AND METHODS: Retrospective database review identified 50 patients treated in our institution for aorto-venous fistulas (AVF) caused by spontaneous AAA rupture in the 20 years 1991-2010. Pulsating abdominal mass and low back pain were the leading symptoms on admission in our patients. Signs of shock, congestive heart failure, or pelvic and lower extremity venous hypertension were present in 48%, 26%, and 75% of the patients, respectively. Diagnosis of AVF was based on physical examination, duplex ultrasonography, conventional angiography, or multislice computed tomography (MSCT). In 40% of the patients the presence of AVF has not been recognized before surgery. All patients were treated with open surgery. RESULTS: After proximal and distal bleeding control the fistula was closed with direct suture (92%) or patch angioplasty (8%). Aortic reconstruction followed with tubular (22%) or bifurcated (78%) synthetic graft. Six (12%) patients died. The causes of death were excessive intraoperative blood loss, myocardial infarction, left colon gangrene and multiple organ failure. CONCLUSIONS: Spontaneous AVFs caused by aneurysmal rupture are not uncommon, and they require prompt surgical or endovascular treatment. Routine use of multislice CT in patients with acute aortic syndrome is probably the best way to the correct diagnosis of aorto-venous fistulas and planning of the optimal treatment.