Georgios A. Pitoulias

Use of Abdominal Chimney Grafts is Feasible and Safe: Short-term Results

Purpose: To present our initial experience with the use of chimney grafts in endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) with challenging anatomy. Methods: Among 390 EVAR cases performed at our institution between November 2008 and February 2010, 15 patients (all men; mean age 81.8 years) underwent EVAR with synchronous placement of chimney grafts. The chimney technique involved placing covered stents parallel to the main aortic stent-graft to preserve or rescue flow to aortic branch vessels while extending the proximal fixation zone. All patients presented with pararenal aortic aneurysms with short necks (between 0 and 10 mm long) that required either suprarenal clamping to tailor a proximal anastomosis in open repair or suprarenal fixation to anchor an endoprosthesis. Chimney grafts were implanted into 10 left renal and 5 right renal arteries. Results: The immediate technical success was 100%. One early type II endoleak due to retrograde flow from the inferior mesenteric artery was detected and is under surveillance. Mean follow-up was 6.8 months (range 1–13). One chimney graft occluded 45 days postoperatively; the patient underwent open thrombectomy of the left renal artery and iliorenal bypass. The creatinine value at discharge was 1.6 mg/dL, and resting renal scintigraphy showed 36% perfusion for the left kidney and 64% for the right kidney. During follow-up, no patient required hemodialysis; no aneurysm-related deaths were noted. Conclusion: This limited experience demonstrates that the use of abdominal chimney grafts is feasible and safe. Long-term results in larger patient cohorts are needed evaluate the utility of this alternative endovascular technique.

Early Outcomes for Fenestrated and Chimney Endografts in the Treatment of Pararenal Aortic Pathologies Are Not Significantly Different: A Systematic Review With Pooled Data Analysis

Purpose To compare short-term outcomes between fenestrated and chimney endografts for pararenal aortic pathologies. Methods An English-language literature search up to January 2012 found 129 articles evaluating the immediate outcomes of endovascular repair of degenerative juxta-/suprarenal aortic aneurysms, type I endoleaks, and para-anastomotic aneurysms using the chimney technique or fenestrated endografts. Data concerning thoracoabdominal aortic aneurysms, ruptured aneurysms, and reports with <5 cases were excluded (n=84). An additional 28 articles were excluded for insufficient data, leaving 17 articles for review: 5 dealing with chimney grafts in 123 patients with pararenal aortic pathologies and 12 presenting data on 631 patients undergoing fenestrated stent-grafting. The composite endpoints were 30-day mortality, deterioration of renal function, new postoperative dialysis dependence, and endoleak rate. Results Cumulative 30-day procedure-related mortality was 0.58% (95% CI 0.0% to 2.93%) for the chimney group (n=3) and 1.17% (95% CI 0.26% to 2.09%, p=0.645) for the f-EVAR group (n=9). In the f-EVAR group, 86 (9.67%;95% CI 4.77% to 14.57%) patients suffered from postoperative renal impairment vs. 16 (12.43%) patients in the chimney group (95% CI 2.39% to 22.48%, p=0.628). In the chimney group, 4 (0.57%;95% CI 0.0% to 2.94%) patients required persistent postoperative dialysis in contrast to the 1.33% (95% CI 0.29% to 2.37%, p=0.567) rate (n=9) in patients undergoing f-EVAR. There were also no significant differences recorded in the endoleak rate: 1.93% (95% CI 0.0% to 4.82%) of the chimney patients had a persistent type Ia endoleak vs. 2.06% (95% CI 0.69% to 3.43%) for the f-EVAR group (p=0.939). For type II endoleaks, the rates were 2.16% (95% CI 0.0% to 10.77%) for the chimney group vs. 6.88% (95% CI 1.92% to 11.83%) for the f-EVAR group (p=0.352). No patient in the chimney group had a type III endoleak, and the rate was low in the f-EVAR group (0.32%,95% CI 0.0% to 0.91%, p=0.079). Conclusion No statistically significant differences were found between the two endovascular approaches for pararenal aortic pathologies in terms of 30-day mortality, renal impairment, or endoleak. These findings support the assumption that chimney grafts may be a reliable alternative in the treatment of pararenal aortic pathologies.

Use of chimney grafts in aortic arch pathologies involving the supra-aortic branches.

Purpose To present a clinical experience with the use of chimney grafts in the endovascular repair of aortic arch pathologies involving the supra-aortic branches. Methods The chimney technique consists of endovascular stent or stent-graft placement parallel to the main aortic stent-graft in order to preserve or rescue flow to aortic branch vessels and to allow proximal extension of endograft fixation zones. Between April 2009 and January 2011, 9 patients (7 men; mean age 58 years, range 39–76) had chimney grafts installed to the left subclavian artery (LSA) or left common carotid artery (LCCA) during urgent thoracic endovascular aortic repair (TEVAR) of 5 aortic arch aneurysms, a mobile aortic thrombus with peripheral embolism, symptomatic type B dissection, penetrating aortic ulcer, and persistent type I endoleak after TEVAR. Eight chimney grafts were implanted into the LSA in 6 patients and 5 into the LCCA in the other 3 patients. Results The immediate technical success was 88.9%. The post-TEVAR type I endoleak persisted despite the chimney graft; the patient underwent surgical arch replacement. One patient died within 30 days due to cardiac insufficiency. There were 2 access site complications requiring surgery (brachial artery pseudoaneurysm and heavily calcified femoral artery puncture site). Over a median follow-up of 15 months (range 4–22), all chimney grafts remained patent in the 7 surviving and successfully treated patients. Conclusion The use of chimney grafts in selected aortic arch pathologies with involvement of supra-aortic branches is safe and feasible. Long-term results and large series are needed in order to draw robust conclusions regarding this promising alternative endovascular technique.

The PROTAGORAS study to evaluate the performance of the Endurant stent graft for patients with pararenal pathologic processes treated by the chimney/snorkel endovascular technique

OBJECTIVE The chimney/snorkel endovascular aortic repair (ch-EVAR) is gaining ever-greater acceptance in the treatment of pararenal pathologic processes. However, the published experience includes mainly short-term clinical results with combinations of several abdominal devices and types of chimney grafts. The aim of this study was the midterm evaluation of the Endurant stent graft (Medtronic, Santa Rosa, Calif) as a standard abdominal device for ch-EVAR. METHODS Between January 2009 and January 2013, prospectively collected data of high-risk patients with pararenal pathologic processes who underwent ch-EVAR with placement of the Endurant abdominal device were analyzed. The chimney graft intended for use was a balloon-expandable covered stent. Main outcome measures were aneurysm sac regression and chimney graft patency. RESULTS A total of 187 snorkel/chimney grafts were successfully placed in 128 patients (mean age, 76.6 years). The technical success was 100%. The mean preoperative proximal neck length and aneurysm size were 4.7 mm and 64.8 mm (range, 48-135 mm), respectively. The postoperative new neck length after use of chimney grafts was 18.7 ± 6.3 mm. The mean aneurysm sac decreased significantly (60.8 mm; 95% confidence interval, 2.036-7.084; P = .001) after a mean radiologic follow up of 24.6 ± 17.4 months. Thirty-day mortality and midterm mortality were 0.8% and 17.2%, respectively. Two patients (1.6%) with single chimneys presented with late new onset of type Ia endoleak and underwent additional tube and multiple chimney placement. Primary chimney graft patency was 95.7%. Freedom from chimney graft-related reinterventions was 93.1%. CONCLUSIONS Standard use of the Endurant abdominal device for ch-EVAR in >120 patients is associated with high technical success, significant aneurysm sac regression, and low incidence of secondary procedures after 2-year radiologic follow-up. These results will give significant impetus to device selection, facilitating the standardization of technique.

Surgical versus endovascular repair by iliac branch device of aneurysms involving the iliac bifurcation

OBJECTIVE To evaluate early and late results of open (OR) and endovascular aneurysm repair by iliac side branch device (EVRISB) for aneurysms involving the iliac bifurcation (AIB). METHODS Between January 2004 and March 2010, 118 patients were diagnosed with AIBs and underwent OR or EVRISB at two European vascular centers. Particularly, 64 (54.2%) patients were treated by EVRISB and 54 (45.8%) by OR. In one center, 24 consecutive patients were treated by surgery because this was the standard therapeutic approach until January 2005. For the rest of the study period until March 2010, 64 consecutive patients with AIB suitable for EVRISB underwent placement of branched devices. In the other center, 30 consecutive patients with AIBs were treated by OR because advanced endovascular imaging was not available during the study period. RESULTS No significant differences in demographics, anatomical characteristics, or comorbidities of the patients were recorded between the two groups. Early (30-day) mortality was 0% for EVRISB versus 5.5% for the OR group (P < .001). Major morbidity occurred in 4.6% versus 9.3% of the patient subgroups, respectively (P < .001). Buttock claudication and colonic ischemia were recorded in 5.9% and 2% of OR patients compared with 3.1% and 0% of EVRISB cases (P > .05). Primary patency rates were 98.4% for EVRISB and 100% for OR patients. Primary and secondary endoleak rates of the EVRISB group were 12.5% and 6.3%, respectively. CONCLUSIONS Endovascular repair by iliac branch device of aneurysms involving the iliac bifurcation can be accomplished with very low morbidity and mortality rates. Especially for young active patients or in cases of contralateral occlusion, the preservation of hypogastric artery seems to be a strong argument for use of EVRISB as a preferable therapy option.

Below knee bare nitinol stent placement in high-risk patients with critical limb ischemia is still durable after 24 months of follow-up

BACKGROUND This study evaluated the durability of nitinol stent placement in high-risk patients with chronic critical limb ischemia (CLI) and infrapopliteal lesions after suboptimal balloon angioplasty. METHODS Between January 2006 and January 2009, 53 high-risk patients (24 women; mean age, 71.8 +/- 5.1 years) with CLI underwent infragenicular stent placement with a 4F sheath-compatible self-expanding nitinol stent. Patients had three or more serious cardiopulmonary comorbidities, including chronic obstructive pulmonary disease, congestive heart failure, coronary artery occlusive disease, American Society of Anesthesiologists score >/=3, previous myocardial infarction, coronary stent or bypass, or infection after peripheral revascularization. Endovascular therapy was performed in 30 stenoses and 23 occlusions in 53 patients. The mean stenosis length was 5.5 +/- 1.9 cm. The mean occlusion length was 6.5 +/- 2.9 cm. The mean follow-up was 24.1 +/- 7.3 months and consisted of clinical examination, ankle-brachial index (ABI) measurements, and duplex ultrasound imaging. Digital subtraction angiography was performed if restenosis or reocclusion was suspected. RESULTS The technical success rate was 98.1%. The 24-month cumulative primary patency rate was 75.5%. During the follow-up, two patients underwent successful repeat angioplasty, and four patients required crural bypass. The 24-month secondary patency and freedom from amputation rates were 88.7% and 88.7%, respectively. The mean ABI increased significantly at 12 and 24 months (P < .001). Risk stratification to detect predictors that influenced the patency rate showed that proximal lesions had significant better patency than distal crural lesions (83.3% vs 65.2%, P = .04). The morphology of the lesions (stenoses vs occlusions, P = .88) did not seem to influence primary patency. Four patients died from nonprocedure-related causes during the follow-up, including lung cancer, myocardial infarction, and glioblastoma multiforme. No procedure-related deaths were recorded. CONCLUSIONS The 2-year outcome of our series underscores the value of infrapopliteal nitinol stent placement as a durable bailout treatment option in high-risk CLI patients with suboptimal angioplasty.

Incidence of abdominal wall hernias in patients undergoing aortic surgery for aneurysm or occlusive disease.

Background: The aim of this study was to compare the incidence of abdominal and incisional hernias in patients with abdominal aortic aneurysm (AAA) versus patients with aortoiliac occlusive disease (AOD). Patients and methods: The study included retrospectively 121 patients, who underwent elective aortic surgery due to AAA (n = 63) or AOD (n = 58) in the period between January 1998 and January 2000. The patients were examined for the presence of abdominal hernias upon admission, as well as for the development of incisional hernias on follow-up. Results: The incidence of inguinal hernias was significantly higher in the group AAA (21/6–33.3%) compared to the group with AOD (6/58–10,3%) (p < 0.01). The incidence of other abdominal wall hernias (umbilical, epigastric or miscellaneous hernias) was also significant higher in AAA group. Furthermore, the incidence of inguinal hernias was significantly higher in the subgroup of patients with an aneurysm diameter more than 6 cm (41.5% vs 18.2%, p < 0.05). The mean ...BACKGROUND The aim of this study was to compare the incidence of abdominal and incisional hernias in patients with abdominal aortic aneurysm (AAA) versus patients with aortoiliac occlusive disease (AOD). PATIENTS AND METHODS The study included retrospectively 121 patients, who underwent elective aortic surgery due to AAA (n = 63) or AOD (n = 58) in the period between January 1998 and January 2000. The patients were examined for the presence of abdominal hernias upon admission, as well as for the development of incisional hernias on follow-up. RESULTS The incidence of inguinal hernias was significantly higher in the group AAA (21/6-33.3%) compared to the group with AOD (6/58-10.3%) (p < 0.01). The incidence of other abdominal wall hernias (umbilical, epigastric or miscellaneous hernias) was also significant higher in AAA group. Furthermore, the incidence of inguinal hernias was significantly higher in the subgroup of patients with an aneurysm diameter more than 6 cm (41.5% vs 18.2%, p < 0.05). The mean follow-up of the patients was 1.7 +/- 0.3 years. 7 cases of incisional hernia were noted in the AAA group (11.1%) and only 2 cases in the AOD group (3.4%) (p < 0.05). The size of the aneurysm had no influence on the incidence of incisional hernias in the AAA group. CONCLUSION We conclude that there seems to be an increased incidence of abdominal wall hernias as well as postoperative incisional hernias in patients undergoing aortic surgery for aneurysm disease compared with aortoiliac occlusive disease.

Endovascular Treatment of Iatrogenic and Traumatic Carotid Artery Dissection

This paper reports on the early and midterm results of endovascular treatment of acute carotid artery dissections, its specific problems, and its limitations. We encountered seven patients with symptomatic extracranial carotid artery dissection, three cases of which occurred after carotid endarterectomy, two after carotid angioplasty and stenting, and two after trauma. Balloon-expandable and self-expanding stents were placed using a transfemoral approach. Success in restoring the carotid lumen was achieved in all patients. No procedure-related complications occurred. All patients experienced significant clinical improvement while in the hospital and achieved complete long-term recovery. At follow-up (mean, 22.4 months), good luminal patency of the stented segments was observed. In conclusion, in this small series, primary stent-supported angioplasty seems to be a safe and effective strategy in the treatment of selected patients having acute traumatic extracranial carotid artery dissection, with excellent early and midterm results. Larger series and longer-term follow-up are required before definitive recommendations can be made.

Two-dimensional versus three-dimensional CT angiography in analysis of anatomical suitability for stentgraft repair of abdominal aortic aneurysms:

Background The morphological analysis prior to endovascular abdominal aneurysm repair (EVAR) plays an important role in long-term outcomes. Post-imaging analysis of computed tomographic angiography (CTA) by three-dimensional reconstruction with central lumen line detection (CLL 3D-CTA) enables measurements to be made in orthogonal slices. This might be more precise than equal post-imaging analysis in axial slices by two-dimensional computed tomographic angiography (2D-CTA). Purpose To evaluate the intra- and interobserver variability of CLL 3D-CTA and 2D-CTA post-imaging analysis methods and the agreement between them in pre-EVAR suitability analysis of patients with abdominal aortic aneurysm (AAA). Material and Methods Anonymized CTA data-sets from 70 patients with AAA were analyzed retrospectively. Length measurements included proximal and distal aortic neck lengths and total distance from the lower renal artery to the higher iliac bifurcation. Width measurements included proximal and distal neck diameters, maximum AAA diameter and common iliac diameters just above the iliac bifurcations. The measurements were performed in random order by two vascular surgeons, twice per method with 1-month interval between readings. In the CLL 3D-CTA method we used semi-automated CLL detection by software and manual measurements on CTA slices perpendicular to CLL. The equal measurements in 2D-CTA were performed manually on axial CTA slices using a DICOM viewer workstation. The intra- and interobserver variability, as well as the agreement between the two methods were assessed by Bland-Altman test and bivariate correlation analysis. Results The intraobserver variability was significantly higher in 2D-CTA measurements for both readers. The interobserver variability was significant in 2D-CTA measurements of proximal neck dimensions while the agreement in CLL 3D-CTA analysis between the two readers was excellent in all studied parameters. The agreement between the two suitability analysis techniques was poor for both readers, especially in measurements of proximal necks dimensions and in total aortoiliac length (p = 0.001). Conclusion In pre-EVAR morphological evaluation of AAAs the CLL-3D CTA post-imaging analysis has better intra- and interobserver correlation than 2D-CTA and might represent a useful tool for the proper selection of endografts type and size.

Endovascular Treatment of Profunda Femoris Artery Obstructive Disease: Nonsense or Useful Tool in Selected Cases?

BACKGROUND To evaluate the therapeutic value of endovascular techniques for the treatment of profunda femoris artery obstructive disease (PFAOD) in critical limb ischaemia (CLI) patients, with technically demanding open profunda repair. DESIGN Retrospective study of prospectively collected data of 15 consecutive CLI patients with technically demanding surgical treatment of PFAOD, that were treated by endovascular means in two European Centers of Vascular Surgery. MATERIALS All patients had critical limb ischaemia with a history of at least two previous vascular reconstructions in the ipsilateral groin and severe co-morbid conditions. All patients had good common femoral artery flow, long occlusion of the superficial femoral and popliteal arteries and impairment of crural arteries. METHODS Twelve patients underwent balloon angioplasty alone and, in the other three cases, an additional stent placement was necessary, due to flow-limiting dissection. The follow-up (mean 29.2+/-10 months) included a surveillance protocol with the best medical treatment and duplex scanning at 1, 3, 6, 12 months and yearly thereafter. RESULTS The endovascular approach was technically successful in all cases and the procedure-related morbidity and mortality rates were 0% for the entire follow-up period. The 3-year primary and secondary patency rates of the treated segment were 80% and 86.7%, respectively. The limb salvage rate was 93.3%. CONCLUSIONS The outcome of our series underscores the therapeutic value of balloon angioplasty in cases of severe PFAOD, as bailout treatment in critical limb ischaemia patients with technically demanding open profunda repair. This procedure can be repeated easily if significant restenosis occurs and provides a useful tool in selected cases.