Paolo Frigatti

Outcomes of endovascular aneurysm repair on renal function compared with open repair

OBJECTIVE Recent studies have shown that progressive renal dysfunction may develop in patients after endovascular aneurysm repair (EVAR). Data are conflicting about the effect of EVAR on renal function compared with open repair (OR). The purpose of this study was to compare the effects of EVAR, both with transrenal fixation (TRF) and infrarenal fixation (IRF), vs OR on renal function detected with renal perfusion scintigraphy (RPS). METHODS A prospective study was carried out from January 2003 to December 2007. Exclusion criteria included factors that could influence post-procedural renal function as: preoperative creatinine clearance level <65 mL/min for men and 60 mL/min for women, renal artery stenosis >60%, renal accessory artery planned to be covered by the endograft, single functioning kidney, hemodialysis, and kidney transplant. To evaluate renal function, an RPS was performed preoperatively, at 30 days, at 6 and 12 months, and then yearly. The glomerular filtration rate (GFR) was estimated with the Gates method. RESULTS During the study period, 403 patients were enrolled; 243 (60%) had OR and 160 (40%) EVAR; among these, 83 (51%) had a TRF and 77 (48%) an IRF; 55 patients were excluded from the study. No statistical differences were observed between groups for demographics and risk factors. Statistically significant differences emerged between OR and EVAR for early postoperative death (4% vs 0%; P = .01). Follow-up ranged from 54 to 126 months (mean, 76 months) for OR and from 54 to 124 months (mean, 74 months) for EVAR (P = NS). Kaplan-Meier analysis survival rate at 9 years was 70% for OR and 58% for EVAR with a risk of secondary procedure of 9% and 34%, respectively (P < .0001). A deterioration of the GFR was observed during the follow-up in both groups with a decrease after 9 years of 11% in the EVAR group and 3% in the OR group respective to baseline (P < .001). A remarkable difference emerged on renal function between EVAR patients who required a secondary procedure compared with the other EVAR patients (P < .005). No significant differences emerged between TFR and IRF for GFR decline during the follow-up period. CONCLUSIONS After EVAR, there is a continuous decline in renal function with respect to OR, regardless of fixation level and independently of pre-existing renal insufficiency. The risk of GFR impairment after EVAR should be taken into consideration in selecting patients with preoperative renal insufficiency.

Suprarenal Fixation of Endograft in Abdominal Aortic Aneurysm Treatment: Focus on Renal Function

Objective:The objective of this work was to evaluate any variation of renal function detected by renal scintigraphy after the suprarenal fixation of endografts for abdominal aortic aneurysm (AAA) repair. Summary Background Data:In the few articles that have considered this problem, renal function was evaluated only by biochemical tests, which are inadequate in demonstrating small changes in renal function and in appreciating the worsening of a single kidneys function. Methods:Between April 1999 and May 2002, 47 patients with an inappropriate infrarenal proximal neck had a suprarenal fixation for AAA. To assess renal function, a technetium-99m diethylene triamine penta-acetic acid (99mTC-DTPA) perfusion scintigraphy was performed preoperatively on the third postoperative day and at 6, 12 months, and then yearly thereafter. Worsening of renal function was defined as a decrease of glomerular filtration rate (GFR) ≥20% (detected with Gates method). Serum creatinine level was tested preoperatively and at the first and third postoperative day. Results:Endograft deployment was technically successful in 44 patients (93.6%); clinical perioperative success was obtained in 46 patients (97.8%). In 12 patients (25.5%), a permanent reduction of the GFR was observed using postoperative 99mTC-DTPA perfusion scintigraphy. By 99m TC-DTPA perfusion scintigraphy, a permanent reduction of GFR was observed postoperatively in 12 patients. A slight GFR reduction (<20%) was present in 7 (14.9%) patients, due to the planned occlusion of accessory renal arteries. A more significant GFR reduction (>20%) was present unexpectedly in 5 (10.6%) patients, in 3 of these a single kidney was involved, in 5 both with an increase of the serum creatinine level >20%. Conclusions:Suprarenal fixation of endografts in AAA treatment is a safe procedure with good early and midterm procedural results and a risk of GFR impairment (>20%) of 10.6%.

Role of aneurysm sac embolization during endovascular aneurysm repair in the prevention of type II endoleak-related complications

OBJECTIVE The goal of this study was to evaluate the role of intraoperative aneurysm sac embolization during endovascular aneurysm repair (EVAR) using a standard dose of coils and fibrin glue in the prevention of type II endoleak (EII). METHODS Two groups were compared: 83 patients underwent standard EVAR during the period 2008-2009 (group A) and 79 patients underwent EVAR during the period 2010-2011 (group B). Computed tomography scans were evaluated with Osirix Pro 4.0 software to obtain aneurysm sac volume. EII rates at the first computed tomography scan follow-up, as well as midterm freedom from EII and freedom from related reintervention, were compared. Preoperative number of patent aortic side branches (inferior mesenteric artery, lumbar arteries, accessory renal arteries), sac thrombus, and sac volume were evaluated for their association with EII in the two groups using multiple logistic regressions. RESULTS Patient characteristics, Society for Vascular Surgery comorbidity scores (0.85 ± 0.44 vs 0.82 ± 0.46; P = .96), and operative time (185 ± 52 vs 179 ± 49; P = .92) were similar for groups A and B. The first computed tomography scan (≤3 months) revealed a significantly larger number of EIIs in group A than in group B (23% vs 10%; P = .02). Spontaneous EII resolution occurred in 65% of patients in group A and in 79% in group B (P = 1.0), whereas sac volume increased in 25% and 10% (P = .63) of cases, respectively. At 18 months (range, 6 months to 4.4 years), overall mean differences in sac volume shrinkage (27 ± 12 cm(3) vs 25 ± 12 cm(3); P = .19) and freedom from EII (92% vs 96%; P = .33) were similar, whereas freedom from reintervention was significantly lower in group A (93% vs 99%; P = .03) than in group B. Multivariate analysis showed preoperative aneurysm sac volume >125 cm(3) to be the only independent significant predictor of EII (odds ratio, 4.0; 95% confidence interval, 1.5-10.5; P = .005). CONCLUSIONS Although further confirmatory studies are needed, sac embolization during EVAR may be a valid approach to preventing EII and its complications during short- and midterm follow-up. More aggressive intraoperative embolization should be considered for patients with a preoperative aneurysm sac volume >125 cm(3).

Drug-coated balloon dilation before carotid artery stenting of post-carotid endarterectomy restenosis

Purpose: To investigate if drug-coated balloon (DCB) predilation may improve the efficacy of carotid artery stenting (CAS) for restenosis after carotid endarterectomy (CEA). Methods: Eighteen consecutive patients (11 men; median age 75 years) with significant restenosis within 24 months of CEA were treated with a paclitaxel-coated DCB prior to CAS. Clinical outcomes and stent patency were systematically appraised. Results: All patients were successfully treated according to this clinical protocol. The only complication occurred in a patient who had a transient ischemic attack during prolonged DCB inflation. At a median follow-up of 18 months, no >50% restenosis was observed on duplex ultrasound scans; however, moderate hyperplasia at the proximal stent edge was found in 4 patients. One patient died at 9 months from a myocardial infarction. Conclusion: Despite the small sample size and in keeping with the historically high risk of recurrent restenosis after CAS for CEA restenosis, this case series suggests that DCB dilation followed by CAS for postsurgical restenosis is feasible, safe, and may be associated with favorable clinical outcomes at midterm follow-up.

Preliminary results of endovascular aneurysm sealing from the multicenter Italian Research on Nellix Endoprosthesis (IRENE) study

Objective: Because of advances in technology and experience of the operator, endovascular aneurysm repair (EVAR) has supplanted open repair to treat abdominal aortic aneurysm (AAA). The low 30‐day mortality and morbidity of EVAR make the endovascular approach particularly suitable for patients at high surgical risk. However, endoleak or endograft migration requiring secondary intervention or open surgical conversion is a limitation of EVAR. The Nellix system (Endologix, Inc, Irvine, Calif) has been designed to seal the entire AAA to overcome these limitations with EVAR. We report the results of a retrospective, multicenter study with endovascular aneurysm sealing (EVAS) aimed to assess technical success, procedure‐related mortality, complications, and reinterventions. Methods: This study included patients selected for elective treatment with the Nellix device per the endovascular repair protocol at 16 Italian vascular centers. All patients were enrolled in a postoperative surveillance imaging program including duplex ultrasound investigations, computed tomography, and magnetic resonance controls following local standards of care. Results: From 2013 to 2015, there were 335 patients (age, 75.5 ± 7.4 years; 316 men) who underwent elective EVAS. In 295 cases (88.0%), EVAS was performed under standard instructions for use of the Nellix system. Preoperative aneurysm diameter was 55.5 ± 9.4 mm (range, 46‐65 mm). The inferior mesenteric artery and lumbar arteries emerging from the AAA were patent in 61.8% and 81.3% of cases, respectively. Chimney grafts were electively carried out in eight cases (2.4%). One (0.3%) intraprocedural type IB endoleak was observed and promptly corrected. Device deployment was successful in all patients, with no perioperative mortality. Early (≤30 days) complications included 1 (0.3%) type IA endoleak, 2 (0.6%) type II endoleaks (0.6%), 2 (0.6%) stent occlusions (0.6%), 3 (0.9%) distal embolizations, and 2 (0.2%) femoral artery dissections. Six (2.9%) patients underwent reinterventions. At 1‐year follow‐up, complications included 3 (1.1%) type II endoleaks, 4 (1.4%) type IA endoleaks, 1 (0.3%) type IB endoleak, 2 (0.7%) distal stent migrations, 5 (1.8%) distal embolizations, and 1 (0.3%) stent occlusion. Twelve patients (3.7%) underwent reinterventions, including four (1.4%) surgical conversions due to aortoduodenal fistula (1), endograft infection (1), and type IA endoleak that was unsuccessfully treated percutaneously (2). Two AAA‐related deaths occurred. Freedom from aneurysm‐related reintervention was 98.3% at 1‐month and 94.7% at 12‐month follow‐up. Conclusions: The preliminary results of this real‐world multicenter study showed that EVAS with Nellix for the management of AAAs appears feasible. This device platform is associated with acceptable procedure‐related mortality and low overall complication and reintervention rates. Definitive conclusions on the value of this novel device await long‐term follow‐up data.

Stent graft exclusion of a renal artery aneurysm at hilum in a case with complex anatomy.

A left renal artery aneurysm (RAA) was incidentally discovered in a 50-year-old hypertensive woman at renal artery duplex scan. The computed tomography angiography scan confirmed an eccentric, 2-cm large aneurysm localized on a prehilar branch with a very twisted and coiled main renal artery. The selective digital subtraction angiography allowed a better understanding of the local complex anatomy; a covered stent was placed with the complete exclusion of the aneurysm. Even if open surgery still represents the treatment of choice, endoluminal approach has been reported as an effective procedure especially in consideration of its low invasiveness. The exclusion by covered stent can be a safe alternative to coil embolization in case of distal RAAs as well.

Identification of optimal device combinations for the chimney endovascular aneurysm repair technique within the PERICLES registry

Objective: The ideal stent combination for chimney endovascular aneurysm repair remains undetermined. Therefore, we sought to identify optimal aortic and chimney stent combinations that are associated with the best outcomes by analyzing the worldwide collected experience in the PERformance of chImney technique for the treatment of Complex aortic pathoLogiES (PERICLES) registry. Methods: The PERICLES registry was reviewed for patients with pararenal aortic disease electively treated from 2008 to 2014. Eleven different aortic devices were identified with three distinct subgroups: group A (n = 224), nitinol/polyester; group B (n = 105), stainless steel/polyester; and group C (n = 69), nitinol/expanded polytetrafluoroethylene. The various chimney stent subtypes included the balloon‐expandable covered stent (BECS), self‐expanding covered stent, and bare‐metal stent. Deidentified aortic and chimney device combinations were compared for risk of chimney occlusion, type IA endoleak, and survival. Effects of high‐volume centers (>100 cases), use of an internal lining chimney stent, number of chimney stents, and number of chimney stent subtypes deployed were also considered. We considered demographics, comorbidities, and aortic anatomic features as potential confounders in all models. Results: The 1‐ and 3‐year freedom from BECS chimney occlusion was not different between groups (group A, 96% ± 2% and 87% ± 5%; groups B and C, 93% ± 3% and 76% ± 10%; Cox model, P = .33). Similarly, when non‐BECS chimney stents were used, no difference in occlusion risk was noted for the three aortic device groupings; however, group C patients receiving BECS did have a trend toward higher occlusion risk relative to group C patients not receiving a BECS chimney stent (hazard ratio [HR], 4.0; 95% confidence interval [CI], 0.85‐18.84; P = .08). Patients receiving multiple chimney stents, irrespective of stent subtype, had a 1.8‐fold increased risk of occlusion for each additional stent (HR, 1.8; 95% CI, 1.2‐2.9; P = .01). Use of a bare‐metal endolining stent doubled the occlusion hazard (HR, 2.1; 95% CI, 1.0‐4.5; P = .05). Risk of type IA endoleak (intraoperatively and postoperatively) did not significantly differ for the aortic devices with BECS use; however, group C patients had higher risk relative to groups A/B without BECS (C vs B: odds ratio [OR], 3.2 [95% CI, 1‐11; P = .05]; C vs A/B: OR, 2.4 [95% CI, 0.9‐6.4; P = .08]). Patients treated at high‐volume centers had significantly lower odds for development of type IA endoleak (OR, 0.2; 95% CI, 0.1‐0.7; P = .01) irrespective of aortic or chimney device combination. Mortality risk was significantly higher in group C + BECS vs group A + BECS (HR, 5.3; 95% CI, 1.6‐17.5; P = .006). The 1‐ and 3‐year survival for groups A, B, and C (+BECS) was as follows: group A, 97% ± 1% and 92% ± 3%; group B, 93% ± 3% and 83% ± 7%; and group C, 84% ± 7% and 63% ± 14%. Use of more than one chimney subtype was associated with increased mortality (HR, 3.2; 95% CI, 1.4‐7.5; P = .006). Conclusions: Within the PERICLES registry, use of nitinol/polyester stent graft devices with BECS during chimney endovascular aneurysm repair is associated with improved survival compared with other aortic endografts. However, this advantage was not observed for non‐BECS repairs. Repairs incorporating multiple chimney subtypes were also associated with increased mortality risk. Importantly, increasing chimney stent number and bare‐metal endolining stents increase chimney occlusion risk, whereas patients treated at low‐volume centers have higher risk of type IA endoleak.

Incidence and prognostic factors related to major adverse cerebrovascular events in patients with complex aortic diseases treated by the chimney technique

Objective: Endovascular aneurysm repair (EVAR) with the chimney technique (ch‐EVAR) has been used for the treatment of aortic aneurysms as an alternative approach to fenestrated endografting or open repair. Nonetheless, the need for an upper extremity arterial access may contribute to a higher risk for periprocedural cerebrovascular events. This study reports on the perioperative cerebral and major adverse cardiac and cerebrovascular events (MACCE) after ch‐EVAR. Methods: The PERICLES registry (PERformance of the chImney technique for the treatment of Complex aortic pathoLogiES) is an international, retrospective multicenter study evaluating the performance of ch‐EVAR for the treatment of complex aortic pathologies. For the purpose of the current analysis, 425 patients treated by ch‐EVAR between 2008 and 2014 were included. The primary outcome of this analysis was the incidence of procedure related cerebrovascular events defined as transient ischemic attack or stroke. The secondary end point was in‐hospital MACCE, including acute coronary syndrome, stroke, and death of any cause. Results: The incidence of clinical relevant cerebrovascular events was 1.9% (8/425). A postoperative transient ischemic attack was observed in four patients (0.95%) and a stroke in additional four (0.95%). Three patients died during the hospital stay secondary to sequelae from postoperative stroke. A prior history of stroke/transient ischemic attack, atrial fibrillation, previous carotid revascularization, or known carotid artery disease did not significantly increase the risk for adverse neurologic events. The overall MACCE rate amounted to 8.5% (36/425). Logistic regression analysis revealed that the use of bilateral upper extremity access (odds ratio [OR], 2.79; 95% confidence interval [CI], 1.04‐7.45]), aneurysm rupture (OR, 5.33; 95% CI, 1.74‐16.33), and a prolonged operation time (>290 minutes; OR, 1.005; 95% CI, 1.001‐1.008) were associated with a significantly increased risk for MACCE. Conclusions: This analysis demonstrates that ch‐EVAR is associated with a relatively low rate of cerebrovascular events. However, a postoperative stroke is associated with increased mortality. Ruptured aneurysms, bilateral upper extremity access as in case of multiple chimney graft placement, and longer operative times were identified as independent risk factors for MACCE.

Modification of the Viabahn Padova Sutureless Technique for Challenging Anastomosis Between a Prosthetic Graft and a Circumferentially Calcified Target Artery

Purpose To describe modification of the Viabahn Padova Sutureless (ViPS) technique for challenging anastomosis between a prosthetic graft and a circumferentially calcified target artery. Technique The technique is demonstrated in a 75-year-old man with complete superficial femoral artery (SFA) occlusion and reconstitution of a circumferentially calcified above-knee popliteal artery. A 7-mm Viabahn endoprosthesis with its constraining string was withdrawn from its delivery system; the string at the proximal edge of the stent was gently cut with a scalpel, causing the proximal part of the stent to deploy, while the undeployed distal tip with its smooth profile retained its commercial orientation. The proximal end was subsequently sutured to a 7-mm polytetrafluoroethylene (PTFE) graft. After surgical exposure, the popliteal artery was transected, and the undeployed distal portion of the Viabahn was inserted into the distal segment, supported by a stiff guidewire. By pulling the constraining string, the stent was deployed in a “non-reversed” fashion and subsequently dilated to achieve optimal apposition. Finally, the proximal end of the PTFE graft was tunneled under the sartorius muscle and sutured to the common femoral artery. Conclusion This modification to the ViPS technique using a “non-reversed” method of Viabahn stent preparation allows a safer and more accurate deployment of the endoprosthesis in the calcified target artery.