Large, single-center databases and the evolution of endovascular therapy for complex aortic aneurysms

Early experience with patient-specific unibody bifurcated fenestrated-branched devices for complex endovascular aortic aneurysm repair

OBJECTIVE

Short distances between the lowest visceral/renal artery and the aortic bifurcation are technically challenging during complex endovascular aortic aneurysm repair (EVAR), particularly after previous infrarenal repair. Traditionally, inverted limb bifurcated devices have been used in addition to fenestrated-branched (FB) endografts, but short overlap, difficult cannulation, and potential crushing of bridging stents are limitations for their use. This study reviews the early experience of patient-specific company manufactured devices (PS-CMDs) with a unibody bifurcated FB design for complex EVAR.

METHODS

Consecutive complex EVAR procedures over a 34-month period with unibody bifurcated FB-devices as part of physician-sponsored investigational device exemption studies at two institutions were reviewed. Unibody bifurcated FB designs included FB bifurcated or fenestrated inverted limb devices. End points included technical success, survival, frequency of type I or III endoleaks, limb occlusion, and secondary interventions.

RESULTS

Among 168 patients undergoing complex EVAR, 33 patients (19.6%; 78.7% male; mean age, 77 years) received unibody bifurcated FB PS-CMDs. FB bifurcated and fenestrated inverted limb devices were used in 31 (93.9%) and 2 (6.06%) patients, respectively. The median maximum aneurysm diameter was 61 mm (interquartile range [IQR], 55-69 mm). Prior EVAR was reported by 29 patients (87.9%), of whom 2 (6.06%) had suprarenal stents. A short distance between the lowest renal artery and aortic bifurcation was demonstrated in 30 patients (90.9%), with median distance of 47 mm (IQR, 38-54 mm). Preloaded devices were used in 23 patients (69.7%). A total of 128 fenestrations were planned; 22 (17.2%) were preloaded with guidewires and 5 (3.9%) with catheters. The median operative time was 238 minutes (226-300 minutes), with a median fluoroscopy time of 65.5 minutes (IQR, 56.0-77.7 minutes) and a median dose area product of 147 mGy∗cm2 (IQR, 105-194 mGy∗cm2). Exclusive femoral access was used in 14 procedures (42.4%). Technical success was 100%. Target vessel primary patency was 100% at a median follow-up time of 11.7 months (IQR, 3.5-18.6 months). Two patients (6.06%) required reintervention for iliac occlusion; one patient required stenting and the other a femoral-femoral bypass. No aortic-related deaths occurred after the procedure. During follow-up, 11 type II endoleaks (33.3%) and 1 type Ib endoleak (3.03%) were detected; the latter was treated with leg extension. No type Ia or III endoleaks occurred.

CONCLUSIONS

Complex EVAR using unibody bifurcated FB-PS-CMDs is a simple, safe, and cost-effective alternative for the treatment of patients with short distances between the renal arteries and the aortic bifurcation. Further studies are required to assess benefits and durability of unibody bifurcated FB devices.

One-hundred Consecutive Physician-Modified Fenestrated Endovascular Aneurysm Repair of Pararenal and Thoracoabdominal Aortic Aneurysms Using the Terumo TREO Stent Graft

BACKGROUND

Fenestrated endovascular aortic aneurysm repair (FEVAR) has been widely applied for the treatment of pararenal (PAA) and thoracoabdominal aortic aneurysms (TAAA). If custom-made devices or off-the-shelf devices are not available, physician-modified endografts (PMEGs) are an alternative device option. Several different endograft platforms have been used for PMEG; however, minimal data exists on utilizing the Terumo TREO abdominal stent graft system in this setting. The purpose of this study was to evaluate our single-center experience treating PAA and TAAA, with a physician-modified FEVAR, using the Terumo TREO platform.

METHODS

A prospective database of consecutive patients with PAA and TAAA treated at a single center, with a FEVAR, utilizing a PMEG device between March 2021 and September 2023 was queried for those having a Terumo TREO device implanted. The demographics, operative details, and postoperative complications were analyzed. The rates of technical success, type I or III endoleak, branch vessel status, reintervention, and 2-year survival were also assessed.

RESULTS

Of the 153 patients who underwent FEVAR with a PMEG device during the study period, 100 had repair using a Terumo TREO stent graft. The mean age of the cohort was 73.7 ± 7.0 years with the majority suffering from hypertension (n = 94, 94%), coronary artery disease (n = 51, 51%), and chronic obstructive pulmonary disease (n = 40, 40%). Thirty-four patients (34%) had a prior failed EVAR device in place. The mean aneurysm size was 66.0 ± 13.7 mm, with 58 (50%) patients classified as PAA and 30 (30%) patients as an extent IV TAAA. Six (6%) patients presented with symptomatic/ruptured aneurysms. The average number of target arteries incorporated per patient was 3.8 ± 0.6. The overall technical success was 99%, procedure time was 218 ± 116 min, contrast volume was 82 ± 21 mL, and cumulative air kerma was 3,054 ± 1,560 mGy. Postoperative complications were present in 20 patients (20%), and 2 patients (2%) died within 30 days. Rates of type I or III endoleak, branch vessel stenosis or occlusion, and reintervention were 2%, 1%, and 7%, respectively. The two-year overall survival was 87%.

CONCLUSIONS

Treatment of PAA and the extent IV TAAA using a physician-modified fenestrated Terumo TREO endograft is safe and effective. This large, early experience using the Terumo TREO platform supports preferential use of this device in this setting due to the device design and low likelihood of type I or III endoleak.

Mid-term Outcomes of Physician-Modified Fenestrated or Branched Endovascular Repair for Post-dissection Thoracoabdominal Aortic Aneurysms

PURPOSE

To report the early experience and mid-term outcomes of physician-modified fenestrated or branched endovascular repair (PM-F/BEVAR) for patients with post-dissection thoracoabdominal aortic aneurysm (PD-TAAA).

METHODS

PD-TAAA patients treated with PM-F/BEVAR between December 2014 and September 2020 in our institution were retrospectively analyzed.

RESULTS

Out of the 39 patients, technical success defined as successful deployment of all stent grafts with patent target vessels (TVs) and exclusion of the lesion without type I or III endoleak was achieved in 35 patients (89.7%). A total of 126 TVs were successfully reconstructed. Thirty-day mortality was 0%. Seven major adverse events occurred including one acute kidney injury, four renal infarctions, one retroperitoneal hematoma and one left renal artery occlusion. Seven type II endoleak and three type III endoleak were detected. During a mean 29.4 ± 15.5 months follow-up period, the mortality was zero. Three renal arteries and one external iliac artery occluded in four patients. No other new onset major adverse event occurred. No patient required reintervention. One type II endoleak spontaneously resolved, while the remaining six remained stable. One early type III endoleak diminished, and one new type III endoleak occurred at 2 months. The primary patency of TV was 96.8% (120/124). Shrinkage or stability of aneurysm diameter can be observed in 38 patients (97.4%). The false lumen thrombosis rate was 89.7% (35/39).

CONCLUSIONS

The present study showed encouraging results of PM-F/BEVAR for treatment of PD-TAAAs.

LEVEL OF EVIDENCE

Level 4, Case Series.

Female Sex Portends Worse Long-Term Survival after Open Type I-III Thoracoabdominal Aneurysm Repair

BACKGROUND

Although outcomes after infrarenal abdominal aortic aneurysm surgery are worse in females, sex-specific differences in outcomes after open thoracoabdominal aortic aneurysm (TAAA) repair are less clear. The goal of this study was to identify sex-based disparities in short- and long-term outcomes after open type I-III TAAA surgery.

METHODS

All open type I-III TAAA repairs performed from 1987 to 2015 were evaluated using an institutional database. Charts were retrospectively evaluated for perioperative outcomes: major adverse events (MAEs), in-hospital death, and long-term survival. Univariate analysis was performed using the Fisher's exact test for categorical variables and the Wilcoxon rank-sum test for continuous variables. Logistic regression was used for in-hospital end points; survival analyses were performed with Cox proportional hazards modeling and Kaplan-Meier techniques. Sensitivity analyses were performed for relevant multivariable models, one with ruptures removed and another evaluating only repairs performed before 2006 to account for any selection bias due to wider use of complex endovascular technology.

RESULTS

Five-hundred sixteen patients underwent open type I-III TAAA repair during the study period. Females accounted for 54.3% (n = 280) of the cohort. Women were older, less likely to have a chronic dissection etiology, more likely to present with a symptomatic/ruptured lesion, and had a lower admission creatinine than men. Perioperative death occurred in 23 men (9.8%) and 19 women (6.8%) (P = 0.26); 133 women (47.3%) and 116 men (49.2%) suffered an MAE (P = 0.72). Multivariable analyses revealed no sex-based difference in perioperative death (Female sex adjusted odds ratio (AOR): 0.72, 95% confidence interval (CI): 0.4-1.4, P = 0.34) or MAE (AOR: 1.0 CI: 0.7-1.5, P = 0.82). Unadjusted survival at five years was 50% for women and 67% for men (log-rank P < 0.001). Female sex was an independent predictor of decreased survival (hazard ratio (HR): 1.5 95% CI: 1.2-1.9, P = 0.001) when adjusted for age, aneurysm extent, creatinine, chronic obstructive pulmonary disease, and ruptures. After removing all ruptures, female sex remained nonpredictive of perioperative death (AOR: 1.1, 95% CI 0.5-2.5, P = 0.75) or MAE (AOR: 1.2, CI: 0.8-1.9, P = 0.31) and predictive of decreased long-term survival (HR: 1.5, 95% CI: 1.2-2.0, P = 0.001).

CONCLUSIONS

Those undergoing open type I-III TAAA repair have similar rates of perioperative mortality and MAEs, regardless of sex. However, female sex is an independent risk factor for decreased long-term survival.

Outcomes and complications after fenestrated-branched endovascular aortic repair

OBJECTIVE

To report the outcomes of patients enrolled in a physician-sponsored investigational device exemption trial for endovascular treatment of complex thoracoabdominal aortic aneurysms with fenestrated and/or branched devices.

METHODS

This study represents a retrospective analysis of a prospectively maintained database of patients enrolled in a physician-sponsored investigational device exemption trial for endovascular treatment of complex thoracoabdominal aneurysms between July 2012 and July 2017. Subjects included high-risk patients for open repair and patients with unsuitable anatomy for either standard endovascular aneurysm repair or Zenith (Cook Medical, Bloomington, Ind) fenestrated device. Aneurysm classification was based upon Crawford classification. We included the pararenal and paravisceral aneurysms in the type IV aneurysm group, because the repair of these aneurysms usually involved treatment of all four visceral branches. The endografts implanted were custom manufactured devices or off-the-shelf devices based on the Cook Zenith platform. Variables analyzed included preoperative demographics and comorbidities, anatomic aneurysmal characteristics, procedural details, and perioperative complications.

RESULTS

One -hundred fifty patients with a mean age of 71 ± 7.9 years were treated; 69% were male. Tobacco use (93%) and hypertension (91%) were the most common risk factors. Fifty-seven patients (38%) had a history of previous aortic repair. The mean aneurysm diameter was 62 ± 12 mm and 14 (9%) aneurysms were associated with chronic dissection. A total of 573 visceral vessels were incorporated (celiac artery/superior mesenteric artery [287 vessels], renal arteries [275 vessels], and 11 additional vessels) and 539 were stented. The celiac artery/superior mesenteric artery received a fenestrated design in 76.1% of cases. Branch designs were used in the renal artery in 13.2%, with the remainder treated with fenestrations. Spinal cord drainage was used in 51% of patients (76/150). The mean operative time, fluoroscopy time, and estimated blood loss were 283 ± 89 minutes, 83 ± 38 minutes, and 417 ± 404 mL, respectively. There were five patients (3.3%) with intraoperative complications, resulting in one intraoperative death. The early mortality was 2.7% (4/150). Major complications included respiratory failure in 7% (10/150), stroke and myocardial infarction in 0.7% each (1/150), and paraplegia in 2.7% (4/150). Acute kidney injury occurred in 4.7% of patients (7/150), two of whom required temporary dialysis. Thirty-nine percent of patients experienced at least one complication. Early branch vessel patency was 99.8% (525/526). Survival, primary, and primary-assisted branch patency at 2 years of follow-up were 79%, 97%, and 99%, respectively.

CONCLUSIONS

Endovascular repair of complex aneurysms is safe and effective when performed in a high-volume center experienced in aortic disease management. Branch vessels patency and the low incidence of paraplegia and mortality support expanded use to treat most complex thoracoabdominal aortic aneurysms.

Evolution from physician-modified to company-manufactured fenestrated-branched endografts to treat pararenal and thoracoabdominal aortic aneurysms

OBJECTIVE

The purpose of this study was to review treatment trends and outcomes of patients who underwent fenestrated-branched endovascular aneurysm repair (F-BEVAR) of pararenal aneurysms (PRAs) or thoracoabdominal aortic aneurysms (TAAAs) using physician-modified endografts (PMEGs) or company-manufactured devices (CMDs).

METHODS

We reviewed the clinical data of 316 consecutive patients (242 male patients; mean age, 75 ± 8 years) who underwent F-BEVAR between 2007 and 2016. F-BEVAR was performed under two prospective investigational device exemption protocols since 2013. End points were mortality, major adverse events (MAEs), patient survival, reintervention, branch instability, aneurysm-related mortality, renal function deterioration, and target vessel patency.

RESULTS

There were 145 patients (46%) treated by PMEGs (84 PRAs, 26 extent IV and 35 extent I-III TAAAs) and 171 patients (54%) who had CMDs (88 PRAs, 42 extent IV and 41 extent I-III TAAAs). Choice of endograft evolved from PMEGs in 131 patients (83%) treated in the first half of experience to CMDs in 144 patients (91%) treated in the second half of experience (P < .001). Patients treated by PMEGs had significantly (P < .05) larger aneurysms, more chronic pulmonary and kidney disease, and higher comorbidity severity scores. A total of 1081 renal-mesenteric arteries were targeted in both groups. Technical success was lower for PMEGs (98% vs 99.5%; P = .02). Thirty-day mortality was 5.5% for PMEGs (PRAs, 1.2%; extent IV 3.8% and extent I-III, 17.1%) and 0% for CMDs (P = .0018). Patients treated by PMEGs had significantly more (P < .001) MAEs (48% vs 23%) and longer hospital stay (9 ± 10 days vs 6 ± 6 days; P = .001). Mean follow-up was significantly longer for patients treated by PMEGs (38 ± 26 months vs 14 ± 12 months; P < .001). At 3 years, patient survival (68% ± 4% vs 67% ± 8%; P = .11), freedom from reintervention (68% ± 4% vs 68% ± 8%; P = .17), primary (94% ± 2% vs 92% ± 2%; P = .64) and secondary target vessel patency (98% ± 1% vs 98% ± 1%; P = .89), and freedom from renal function deterioration (75% ± 4% vs 65% ± 6%; P = .24) were similar for patients treated by PMEGs or CMDs, respectively.

CONCLUSIONS

Choice of F-BEVAR evolved from PMEGs to almost exclusively CMDs under physician-sponsored investigational device exemption protocols. PMEG patients had more comorbidities and larger aneurysms. CMDs were performed with higher technical success, no mortality, and fewer MAEs.

Hybrid thoracoabdominal aortic aneurysm repair: is the future here?

Open surgical repair has been the gold standard for thoracoabdominal aortic aneurysm (TAAA) repair for more than 6 decades, but 2 additional options have emerged: total endovascular TAAA repair and a hybrid approach that combines open and endovascular repair. Despite the optimism for an endovascular approach, long-term results for these repairs are still lacking. Some of the issues with this emerging technology include the risk of paraplegia after extensive endovascular repair, the need for multiple reinterventions, continuous stent-graft surveillance, endograft branch stenosis, as well as the significant learning curve. Interest in a hybrid approach has resurged despite the non-superior results compared to open TAAA. Commonly, the focus of the hybrid approach is now on performing a less extensive open TAAA repair, which is then extended with a stent-graft or vice versa. Moreover, this approach is now often performed in two stages in an effort to decrease the associated spinal cord ischemia. Open surgical repair after endovascular aortic repair is increasingly being performed to address serious complications, such as infection or fistula, that cannot be repaired by further endovascular intervention. As with any new technology, there will be an increase in the number of procedure-related complications and a decrease in the number of surgeons who can perform the traditional open operation with good results.