The state of complex endovascular abdominal aortic aneurysm repairs in the Vascular Quality Initiative

BACKGROUND

Endovascular repair of complex abdominal aortic aneurysms has become increasingly common, but reports have mostly been limited to single centers and single devices.

METHODS

We studied all endovascular repairs of complex abdominal aortic aneurysms (zone 6 or caudal) from 2014 to 2018 in the Vascular Quality Initiative. This included all commercially available fenestrated endovascular aneurysm repair (FEVAR), chimney/snorkel repairs, and physician-modified endografts (PMEGs), exclusive of investigational device exemptions and clinical trial devices. We used inverse probability-weighted multilevel logistic regression to compare rates of perioperative outcomes including death, acute kidney injury (AKI), and major adverse cardiac events (MACEs; the composite of death/stroke/myocardial infarction) and Cox regression for long-term mortality.

RESULTS

During the study period, surgeons performed 1396 complex endovascular repairs: 1308 (94%) elective, 63 (4.5%) for symptomatic aneurysms, and 25 (1.8%) for rupture. The number of centers performing complex endovascular repairs expanded steadily from 39 in 2014 to 81 in 2017. There were 880 FEVAR (63%), 256 PMEG (18%), and 260 chimney/snorkel repairs (19%). In elective cases, 3214 visceral vessels were incorporated and revascularized; 120 repairs (9%) involved one vessel, 481 (38%) repairs involved two vessels, 560 (44%) involved three vessels, and 113 (9%) involved four vessels. The mean number of arteries incorporated was 2.5 ± 0.8, with PMEGs involving the most arteries (3.3 ± 0.8 for PMEG vs 2.5 ± 0.6 for FEVAR and 1.9 ± 0.9 for chimney/snorkel; P < .001). PMEGs were used to treat more extensive aneurysms, and more incorporated the celiac and superior mesenteric arteries. There was no change in aneurysm extent, but the length of proximal seal extended over time. Chimney/snorkel cases employed more arm or neck access, had longer procedure times, and used more contrast material. Rates of perioperative death (3.4% for FEVAR vs 2.7% for PMEG vs 6.1% for chimney/snorkel; P = .13) and AKI (17% vs 18% vs 19%; P = .42) were similar, but chimney/snorkel was associated with higher rates of stroke (0.8% vs 0.9% vs 3.3%; P = .03) and MACEs (6.1% vs 5.4% vs 11.7%; P = .02). After adjustment, rates of perioperative death, AKI, and overall complications remained similar, but chimney/snorkel was associated with significantly higher odds of stroke (odds ratio [OR], 7.3 [1.5-36.4]; P = .015), myocardial infarction (OR, 18.7 [2.6-136.8]; P = .004), and MACEs (OR, 11.1 [2.1-58.9]; P = .005). Overall survival after elective repair was 91% at 1 year and 88% at 3 years, with no difference between repair types in crude or adjusted analysis.

CONCLUSIONS

The Vascular Quality Initiative provides a unique opportunity to study the real-world application and outcomes of complex endovascular aneurysm repair. Perioperative morbidity appears to be higher after chimney/snorkel repair, but further study is needed to confirm these findings and to establish the durability of these novel technologies.

Select type I and type III endoleaks at the completion of fenestrated endovascular aneurysm repair resolve spontaneously

OBJECTIVE

The Society for Vascular Surgery reporting standards for endovascular aneurysm repair (EVAR) consider the presence of a type I or type III endoleak a technical failure. However, the nature and implications of these endoleaks in fenestrated EVAR (FEVAR) are not well understood.

METHODS

We performed a single-center retrospective review of 53 patients who underwent FEVAR with the Zenith Fenestrated AAA Endovascular Graft (Cook Medical, Bloomington, Ind) from 2013 to 2018. We excluded one patient without contrast-enhanced postoperative imaging who was lost to follow-up after discharge. Small, slow, type I and type III endoleaks on completion angiography were routinely observed. We identified patients with completion type I or type III endoleaks by angiography review and characterized endoleak type, location, and rate of resolution on initial postoperative imaging.

RESULTS

Fifty-two patients were included; mean age was 75 ± 8 years, 75% were male, and 91% were white. Of 146 visceral vessels (100 renal arteries and 46 superior mesenteric arteries), 145 (99%) were preserved with 103 fenestrations and 43 scallops; 102 (70%) target vessels were stented. After implantation of all device components, 31 patients (60%) had evidence of type I or type III endoleak. Twelve patients (39%) underwent further intervention at the index procedure, and three endoleaks resolved completely. Twenty-eight patients (54%) had a type I or type III endoleak on completion angiography. There were no differences between patients with and without completion endoleaks in baseline demographics, graft design, neck anatomy, or proportion of cases performed within the instructions for use of the device. Perioperative mortality was 1.9%. On initial postoperative imaging, 27 of 28 (96%) endoleaks resolved spontaneously. One small, persistent type IA or type III endoleak was identified on postoperative day 27 and was observed. This endoleak had resolved completely on computed tomography angiography 6 months postoperatively. In patients without a completion endoleak, one type IA endoleak secondary to graft infolding was discovered on postoperative imaging and was successfully treated with placement of endoanchors and Palmaz stent. Median follow-up was 269 days. No additional type I or type III endoleaks were identified in any patient for the duration of follow-up.

CONCLUSIONS

Whereas completion type I and type III endoleaks are common after FEVAR with the ZFEN device, nearly all of these endoleaks resolve spontaneously by the initial postoperative imaging. These results suggest that select completion endoleaks after FEVAR with the ZFEN device do not require intervention at the index procedure.

In-hospital versus postdischarge major adverse events within 30 days following lower extremity revascularization

OBJECTIVE

Studies using hospital discharge data likely underestimate postoperative morbidity and mortality after lower extremity revascularization because they fail to capture postdischarge events. However, the degree of underestimation and the timing of postdischarge complications are not well-characterized.

METHODS

We used the American College of Surgeons National Surgical Quality Improvement Program procedure-targeted vascular databases from 2011 to 2015 to tabulate 30-day adverse events (in hospital and after discharge) for lower extremity bypass (LEB) and percutaneous vascular interventions (PVIs) performed for claudication and chronic limb-threatening ischemia (CLTI).

RESULTS

A total of 14,125 patients underwent lower extremity revascularization, 8909 patients (63%) with LEB and 5216 (37%) with PVI. For CLTI, total 30-day mortality was similar between PVI and LEB (2.3% vs 2.1%; P = .61), but in-hospital deaths only accounted for 43% of PVI mortality and only 65% of LEB mortality (P ≤ .001). Major adverse cardiac events occurred in 2.9% of PVI patients and 4.6% of LEB patients (P < .001), with postdischarge events accounting for 37% of PVI events and 18% of LEB (P ≤ .001). Although the 30-day reoperation rates were 14% for PVI and 18% for LEB (P < .001), almost one-half occurred after discharge (PVI 46% vs LEB 44%; P = .55). Any postoperative major adverse events (MAEs) occurred in 22% of patients after PVI and 31% after LEB, with more than one-half occurring after discharge (PVI 56% vs LEB 53%; P = .17). For claudicants, total 30-day mortality was 0.4% for PVI and 0.7% for LEB (P = .32), with the vast majority of events occurring after discharge (PVI 90% vs LEB 50%; P = .049). The 30-day reoperation rates were 5.2% for PVI and 8.0% for LEB (P < .001), with more than one-half occurring after discharge (PVI 63% vs LEB 53%; P = .09). Any MAEs occurred in 7.0% of patients after PVI and 17% after bypass, with the majority occurring after discharge (PVI 65% vs LEB 63%; P = .66).

CONCLUSIONS

Most MAEs occur less frequently after PVI than LEB. However, a significant number of major of adverse events after lower extremity revascularization occur after leaving the hospital, especially after PVI, which may overestimate its benefits compared with LEB if only in-hospital data are evaluated. These data demonstrate the importance of reporting 30-day rather than in-hospital outcomes when evaluating postoperative adverse events.

Gastric bypass surgery, but not caloric restriction, decreases dipeptidyl peptidase-4 activity in obese patients with type 2 diabetes

The mechanism by which incretins and their effect on insulin secretion increase markedly following gastric bypass (GBP) surgery is not fully elucidated. We hypothesized that a decrease in the activity of dipeptidyl peptidase-4 (DPP-4), the enzyme which inactivates incretins, may explain the rise in incretin levels post-GBP. Fasting plasma DPP-4 activity was measured after 10-kg equivalent weight loss by GBP (n = 16) or by caloric restriction (CR,n = 14) in obese patients with type 2 diabetes. DPP-4 activity decreased after GBP by 11.6% (p = 0.01), but not after CR. The increased peak glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) response to oral glucose after GBP did not correlate with DPP-4 activity. The decrease in fasting plasma DPP-4 activity after GBP occurred by a mechanism independent of weight loss and did not relate to change in incretin concentrations. Whether the change in DPP-4 activity contributes to improved diabetes control after GBP remains therefore to be determined.