Stavros A. Antoniou

A meta-analysis of outcomes of endovascular abdominal aortic aneurysm repair in patients with hostile and friendly neck anatomy

BACKGROUND An increasing number of abdominal aortic aneurysms with unfavorable proximal neck anatomy are treated with standard endograft devices. Skepticism exists with regard to the safety and efficacy of this practice. METHODS A systematic review of the literature was undertaken to identify all studies comparing the outcomes of endovascular aneurysm repair (EVAR) in patients with hostile and friendly infrarenal neck anatomy. Hostile neck conditions were defined as conditions that were not consistent with the instructions for use of the endograft devices employed in the selected studies. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models. RESULTS Seven observational studies reporting on 1559 patients (hostile anatomy group, 714 patients; friendly anatomy group, 845 patients) were included. Patients with hostile anatomy required an increased number of adjunctive procedures to achieve proximal seal compared with patients with friendly anatomy (odds ratio [OR], 3.050; 95% confidence interval [CI], 1.884-4.938). Although patients with unfavorable neck anatomy had an increased risk of developing 30-day morbidity (OR, 2.278; 95% CI, 1.025-5.063), no significant differences in the incidence of type I endoleak and reintervention rates within 30 days of treatment between the two groups were identified (OR, 2.467 and 1.082; 95% CI, 0.562-10.823 and 0.096-12.186). Patients with hostile anatomy had a fourfold increased risk of developing type I endoleak (OR, 4.563; 95% CI, 1.430-14.558) and a ninefold increased risk of aneurysm-related mortality within 1 year of treatment (OR, 9.378; 95% CI, 1.595-55.137). CONCLUSIONS Insufficient high-level evidence for or against performing standard EVAR in patients with hostile neck anatomy exists. Our analysis suggests EVAR should be cautiously used in patients with anatomic neck constraints.

Robot-assisted laparoscopic surgery of the colon and rectum

IntroductionLaparoscopic techniques have induced a tremendous revolution in the field of general surgery. Recent multicenter trials have demonstrated similar patient-oriented and oncologic outcomes for laparoscopic colon and rectal resections compared with their open counterparts. Meanwhile, robotic technology has gradually entered the field of general surgery, allowing increased dexterity, improved operative view, and optimal ergonomics. The objective of this study was to review the current status of clinical robotic applications in colorectal surgery.MethodsA systematic review of the literature using the PubMed search engine was undertaken to identify relevant articles. The keywords used in all possible combinations were: surgical robotics, robotic surgery, computer-assisted surgery, colectomy, sigmoid resection, sigmoidectomy, and rectal resection.ResultsThirty-nine case series or comparative nonrandomized studies were identified. A specific interest for robot-assisted rectal surgery during the past few years was recorded in the literature. The retrieved articles included 13 ileocecal resections, 220 right colectomies, 190 left colectomies/sigmoid resections, 440 anterior resections, 149 abdominoperineal/intersphincteric resections, and 11 total/subtotal colectomies. The clinical application of the da Vinci robotic system in right and left/sigmoid colectomies yielded satisfactory results in terms of open conversion (1.1 and 3.8%, respectively) and operative morbidity (13.4 and 15.1%, respectively). Robot-assisted anterior resection was accompanied by a considerably low conversion rate (0.4%), morbidity (9.7%), and adequate number of harvested lymph nodes (14.3, mean).ConclusionsRobotic applications in colorectal surgery are feasible with low conversion rates and favorable morbidity. Further studies are required to evaluate its oncologic and patient-oriented outcomes.

Endovascular repair for ruptured abdominal aortic aneurysm confers an early survival benefit over open repair

BACKGROUND Despite the intuitive advantages of endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (AAAs), uncertainty remains about the optimal management in the absence of convincing high-quality evidence. Our objective was to undertake a comprehensive literature review and perform a meta-analysis of outcome data of treatment modalities for ruptured AAAs. METHODS Systematic searches were conducted of electronic information sources to identify studies comparing perioperative outcomes of EVAR and open repair for AAA rupture. Summary estimates of odds ratios (ORs) or standardized mean difference and 95% confidence intervals (CIs) were obtained with a random-effects model. Meta-regression models were formed to explore potential heterogeneity as a result of changes in practice over time. RESULTS We selected 41 studies for analysis. The entire meta-analysis population comprised 59,941 patients (8201 EVAR patients and 51,740 open repair patients). EVAR was associated with a significantly lower incidence of in-hospital mortality (OR, 0.56; 95% CI, 0.50-0.64; P < .01; meta-analysis of risk-adjusted observational studies and randomized controlled trials: OR, 0.58; 95% CI, 0.46-0.73; P < .01). EVAR patients had a significantly decreased risk of developing respiratory complications (OR, 0.59; 95% CI, 0.49-0.69; P < .01) and acute renal failure (OR, 0.65; 95% CI, 0.55-0.78; P < .01) and a trend toward a reduced incidence of cardiac complications (OR, -0.02; 95% CI, -0.03 to 0.00; P = .05) and mesenteric ischemia (OR, 0.66; 95% CI, 0.44-1.00; P = .05). Patients treated with EVAR had significantly less requirements of intraoperative blood transfusion (standardized mean difference, -0.88; 95% CI, -1.06 to -0.70; P < .01). Random-effects meta-regression revealed no statistical evidence for an association between death and year of publication (P = .19). CONCLUSIONS Our analysis provides evidence to motivate the adoption of an EVAR-first policy in a nonelective setting and the establishment of standardized protocols for the management ruptured AAAs.

A meta-analysis of endovascular versus surgical reconstruction of femoropopliteal arterial disease.

BACKGROUND Controversy exists as to the relative merits of surgical and endovascular treatment of femoropoliteal arterial disease. METHODS A systematic review of the literature was undertaken to identify studies comparing open surgical and percutaneous transluminal methods for the treatment of femoropopliteal arterial disease. Outcome data were pooled and combined overall effect sizes were calculated using fixed or random effects models. RESULTS Four randomized controlled trials and six observational studies reporting on a total of 2817 patients (1387 open, 1430 endovascular) were included. Endovascular treatment was accompanied by lower 30-day morbidity (odds ratio [OR], 2.93; 95% confidence interval [CI], 1.34-6.41) and higher technical failure (OR, 0.10; 95% CI, 0.05-0.22) than bypass surgery, whereas no differences in 30-day mortality between the two groups were identified (OR, 0.92; 95% CI, 0.55-1.51). Higher primary patency in the surgical treatment arm was found at 1 (OR, 2.42; 95% CI, 1.37-4.28), 2 (OR, 2.03; 95% CI, 1.20-3.45), and 3 (OR, 1.48; 95% CI, 1.12-1.97) years of intervention. Progression to amputation was found to occur more commonly in the endovascular group at the end of the second (OR, 0.60; 95% CI, 0.42-0.86) and third (OR, 0.55; 95% CI, 0.39-0.77) year of intervention. Higher amputation-free and overall survival rates were found in the bypass group at 4 years (OR, 1.31; 95% CI, 1.07-1.61 and OR, 1.29; 95% CI, 1.04-1.61, respectively). CONCLUSIONS High-level evidence demonstrating the superiority of one method over the other is lacking. An endovascular-first approach may be advisable in patients with significant comorbidity, whereas for fit patients with a longer-term perspective a bypass procedure may be offered as a first-line interventional treatment.

Late Rupture of Abdominal Aortic Aneurysm After Previous Endovascular Repair: A Systematic Review and Meta-analysis.

Purpose: To report a systematic literature review of late rupture of abdominal aortic aneurysm (AAA) after endovascular aneurysm repair (EVAR) and the results of a pooled analysis of causes, treatment, and outcomes. Methods: Electronic information sources and bibliographic reference lists were interrogated using a combination of free text and controlled vocabulary searches; 11 articles were ultimately identified that fulfilled the inclusion criteria. The articles reported a total of 190 patients who were included in the qualitative and quantitative synthesis. Mortality within 30 days or during the admission with aneurysm rupture was a primary endpoint; major perioperative morbidity was a secondary endpoint. A meta-analysis was performed for 30-day/in-hospital mortality using the random effects model. Results: A total of 152 ruptures occurred after 16,974 EVAR procedures reported by 8 of the case series, giving an incidence of 0.9% [95% confidence interval (CI) 0.77 to 1.05]. The mean time to rupture was 37 months. Twenty-nine percent (95% CI 20 to 39) of the patients had at least one previous secondary endovascular intervention following the initial EVAR, and 37% (95% CI 30 to 45) were not compliant with surveillance. Type I and III endoleaks were the predominant causes of rupture. Open surgical treatment was undertaken in 61% (95% CI 53 to 68) of the patients who underwent treatment. The pooled estimate for perioperative mortality was 32% (95% CI 24 to 41). A significantly lower mortality was found with endovascular treatment than open surgical management (p=0.027). Conclusion: Graft-related endoleaks appear to be the predominant causes of late aneurysm rupture. Quality of and compliance with post-EVAR surveillance are important factors in late rupture; a large proportion of late ruptures are amenable to endovascular treatment.

Lower recurrence rates after mesh-reinforced versus simple hiatal hernia repair: a meta-analysis of randomized trials.

Mesh hiatoplasty has been postulated to reduce recurrence rates, it is however prone to esophageal stricture, and early-term and mid-term dysphagia. The present meta-analysis was designed to compare the outcome between mesh-reinforced and primary hiatal hernia repair. The databases of Medline, EMBASE, and the Cochrane Library were searched; only randomized controlled trials entered the meta-analytical model. Anatomic recurrence documented by barium oesophagography was defined as the primary outcome endpoint. Three randomized controlled trials reporting the outcomes of 267 patients were identified. The follow-up period ranged between 6 and 12 months. The weighted mean recurrence rates after primary and mesh-reinforced hiatoplasty were 24.3% and 5.8%, respectively. Pooled analysis demonstrated increased risk of recurrence in primary hiatal closure (odds ratio, 4.2; 95% confidence interval, 1.8-9.5; P=0.001). Mesh-reinforced hiatal hernia repair is associated with an approximately 4-fold decreased risk of recurrence in comparison with simple repair. The long-term results of mesh-augmented hiatal closure remain to be investigated.

Meta-analysis of randomized trials on single-incision laparoscopic versus conventional laparoscopic appendectomy

BACKGROUND Single-incision laparoscopic appendectomy has emerged as a less invasive alternative to conventional laparoscopic surgery. High-quality relevant evidence is limited. METHODS A systematic review of electronic information sources was undertaken, with the objective of identifying randomized trials that compared single-incision with conventional laparoscopic appendectomy. Outcome measures included 30-day morbidity, abdominal abscess, wound infection, open conversion, reoperation, operative time, length of hospital stay, and postoperative pain. Fixed-effects and random-effects models were used to calculate combined overall effect sizes of pooled data. Data are presented as odds ratios or weighted mean differences with 95% confidence intervals (CIs). RESULTS Five randomized trials were identified, with a total of 746 patients. Thirty-day morbidity (9.6% vs 8.6%; odds ratio, 1.14; 95% CI, .69 to 1.89) and wound infection rates were similar between single-incision and conventional laparoscopy (4.0% vs 4.8%; odds ratio, .83; 95% CI, .41 to 1.68), whereas the duration of surgery was longer in the single-incision group (46.3 vs 40.7 minutes; weighted mean difference, 6.01; 95% CI, 2.26 to 9.76). Available data were not adequately robust to reach conclusions regarding the remaining outcome measures. CONCLUSIONS Similar postoperative morbidity and wound infection rates for single-incision and conventional laparoscopic appendectomy are supported by the current literature, but single-incision surgery requires longer operative time.

Meta-Analysis of Outcomes of Endovascular Treatment of Infrapopliteal Occlusive Disease With Drug-Eluting Stents

Purpose To review emerging evidence regarding the use of bare metal (BMS) vs. drug-eluting stents (DES) in the treatment of infrapopliteal occlusive disease. Methods A systematic review of the literature was undertaken to identify all studies comparing stent treatments of infragenicular vessels in patients with chronic lower limb ischemia. Validated methods to assess the methodological quality of the included studies were applied. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models. The search identified 4 randomized clinical trials and 2 observational studies reporting on 544 patients (287 treated with DES and 257 treated with BMS). Data are presented as the odds ratio (OR) with 95% confidence interval (CI) and the number-needed-to-treat (NNT). Results Primary patency, freedom from target lesion revascularization, and clinical improvement at 1 year were significantly higher in the DES recipients compared to patients treated with BMS (OR 4.511, 95% CI 2.897 to 7.024, p<0.001, NNT 3.5; OR 3.238, 95% CI 2.019 to 5.192, p<0.001, NNT 6.0; and OR 1.792, 95% CI 1.039 to 3.090, p=0.036, NNT 7.3, respectively). No significant differences in limb salvage and overall survival at 1 year were identified between the groups (OR 2.008, 95% CI 0.722 to 5.585, p=0.181; OR 1.262, 95% CI 0.605 to 2.634, p=0.535, respectively). Sensitivity analyses investigating the potential effects of study design and type of DES on the combined outcome estimates validated the results. Conclusion Our analysis has demonstrated superior short-term results with DES compared with BMS, expressed by increased patency and freedom from target lesion revascularization. The influence of this finding on clinical surrogate endpoints, such as limb salvage, remains unknown.

Meta-analysis and Meta-Regression Analysis of Outcomes of Carotid Endarterectomy and Stenting in the Elderly

IMPORTANCE Uncertainty exists about the influence of advanced age on the outcomes of carotid revascularization. OBJECTIVE To undertake a comprehensive review of the literature and conduct an analysis of the outcomes of carotid interventions in the elderly. DESIGN AND SETTING A systematic literature review was conducted to identify articles comparing early outcomes of carotid endarterectomy (CEA) or carotid stenting (CAS) in elderly and young patients. MAIN OUTCOMES AND MEASURES Combined overall effect sizes were calculated using fixed or random effects models. Meta-regression models were formed to explore potential heterogeneity as a result of changes in practice over time. RESULTS Our analysis comprised 44 studies reporting data on 512,685 CEA and 75,201 CAS procedures. Carotid stenting was associated with increased incidence of stroke in elderly patients compared with their young counterparts (odds ratio [OR], 1.56; 95% CI, 1.40-1.75), whereas CEA had equivalent cerebrovascular outcomes in old and young age groups (OR, 0.94; 95% CI, 0.88-0.99). Carotid stenting had similar peri-interventional mortality risks in old and young patients (OR, 0.86; 95% CI, 0.72-1.03), whereas CEA was associated with heightened mortality in elderly patients (OR, 1.62; 95% CI, 1.47-1.77). The incidence of myocardial infarction was increased in patients of advanced age in both CEA and CAS (OR, 1.64; 95% CI, 1.57-1.72 and OR, 1.30; 95% CI, 1.16-1.45, respectively). Meta-regression analyses revealed a significant effect of publication date on peri-interventional stroke (P = .003) and mortality (P < .001) in CAS. CONCLUSIONS AND RELEVANCE Age should be considered when planning a carotid intervention. Carotid stenting has an increased risk of adverse cerebrovascular events in elderly patients but mortality equivalent to younger patients. Carotid endarterectomy is associated with similar neurologic outcomes in elderly and young patients, at the expense of increased mortality.

The role of matrix metalloproteinases in the pathogenesis of abdominal wall hernias.

Surgical treatment of abdominal wall hernia has been based for many decades on observational evidence, as the disease physiopathology was ambiguous. The long‐standing hypothesis of abnormal collagen metabolism as a causative factor of hernia disease seems to become substantiated by modern investigations, demonstrating a link between abnormal matrix metalloproteinase (MMP) expression and abdominal wall hernia. Current evidence suggests a strong correlation between MMP‐2 and direct inguinal hernia, while the role of this MMP in indirect, incisional and recurrent hernias has not been completely elucidated yet. Furthermore, MMP‐1 and MMP‐13 seem to be implicated in the physiopathology of recurrent hernia, while limited data link MMP‐1 also with incisional hernia formation. Despite the importance of MMP‐9 in wound healing mechanisms, its role in hernia pathogenesis has not been adequately investigated. Future research is expected to decipher the complex physiopathological mechanisms of hernia development and provide a basis for potential therapeutic applications.