Proximal Instructions for Use Violations in Elective Endovascular Aneurysm Repair in the Vascular Quality Initiative: Retrospective Analysis.

BACKGROUND: Endovascular aneurysm repair (EVAR) is often attempted in patients with marginal anatomy. These patients' midterm outcomes are available in the Vascular Quality Initiative for analysis. STUDY DESIGN: Retrospective analysis of prospectively collected data in the Vascular Quality Initiative from patients who underwent elective infrarenal EVAR between 2011 and 2018. Each EVAR was identified as either on- or off-instructions for use (IFU) based on aortic neck criteria. Multivariable logistic regression models were used to assess associations between aneurysm sac enlargement, reintervention, and type Ia endoleak with IFU status. Kaplan-Meier time-to-event models estimated reintervention, aneurysm sac enlargement, and overall survival. RESULTS: We identified 5,488 patients with at least 1 follow-up recorded. Those treated off-IFU included 1,236 patients ([23%] mean follow-up 401 days) compared with 4,252 (77%) treated on-IFU (mean follow-up 406 days). There was no evidence of significant differences in crude 30-day survival (96% vs 97%; p = 0.28) or estimated 2-year survival (97% vs 97%; log-rank p = 0.28). Crude type Ia endoleak frequency was greater in patients treated off IFU (2% vs 1%; p = 0.03). Off-IFU EVAR was associated with type Ia endoleak on multivariable regression model (odds ratio 1.84 [95% CI 1.23 to 2.76]; p = 0.003). Patients treated off IFU vs on IFU experienced had increased risk of reintervention within 2 years (7% vs 5%; log-rank p = 0.02), a finding consistent with results from the Cox modeling (hazard ratio 1.38 [95% CI 1.06 to 1.81]; p = 0.02). CONCLUSIONS: Patients treated off IFU were at greater risk for type Ia endoleak and reintervention, although they had similar 2-year survival compared with those treated on IFU. Patients with anatomy outside IFU should be considered for open surgery or complex endovascular repair to reduce the probability for revision.

A Novel Quality of Life Instrument for Patients with an Abdominal Aortic Aneurysm.

OBJECTIVE: The surveillance and treatment of abdominal aortic aneurysms (AAAs) may impact patient quality of life (QOL). A novel AAA specific QOL instrument was developed and validated to quantify the impact of AAA surveillance on QOL. METHODS: The study was performed in two phases: development (2011-2013) and validation (2013-2014) of a survey instrument. Content was informed by focus groups at three centres (22 patients) and two multidisciplinary physician focus groups (6 vascular surgeons, 7 primary care providers). Cognitive interviews (17 patients) ensured questions were understood as intended. The final survey was mailed to AAA patients at six US institutions. Patients were scored on two AAA specific domains of QOL: emotional impact (EIS) and behavioural change (BCS), range 0-100 with higher scores indicating worse quality of life. Test retest reliability and internal consistency were assessed. Discriminant validity was determined by comparing scores between patients under surveillance vs. those who had undergone AAA repair. Scores were externally validated by correlation with the Short Form (SF)-12. RESULTS: A total of 1,008 (73%) of 1,373 patients returned surveys: 351 (35%) were under surveillance, 657 (65%) had undergone repair (endovascular, 414; open, 179; unsure, 64). Median EIS was 11 (range 0-95; IQR 7-26). Median BCS was 13 (range 0-100; IQR 9-47). To test reliability, 337 patients repeated the survey after four weeks with no significant differences between scores over time. EIS and BCS demonstrated good internal consistency (Cronbach's Alpha 0.85 and 0.75 respectively). There was strong correlation between scores (r = 0.53) and both related moderately to SF-12 scores (r = 0.45 and r = 0.39, respectively). Patients under AAA surveillance had worse EIS than repair patients (22 vs. 13; p < .001). Patients with a higher perceived rupture risk had a worse EIS (45 vs. 12; p < .001) and BCS (30 vs. 13; p < .001). CONCLUSIONS: An AAA specific QOL instrument was successfully created and validated. The range of impact on QOL by AAA surveillance is broad. For most patients the impact is minimal, but for some, especially those with a greater perceived rupture risk, it is severe.

Arteriovenous fistula patency in the 3 years following vonapanitase and placebo treatment.

OBJECTIVE: This study explored the long-term outcomes of arteriovenous fistulas treated with vonapanitase (recombinant human elastase) at the time of surgical creation. METHODS: This was a randomized, double-blind, placebo-controlled trial of 151 patients undergoing radiocephalic or brachiocephalic arteriovenous fistula creation who were randomized equally to placebo, vonapanitase 10 µg, or vonapanitase 30 µg. The results after 1 year of follow-up were previously reported. The current analysis occurred when the last patient treated was observed for 3 years. For the current analysis, the primary end point was primary patency; the secondary end points included secondary patency, use of the fistula for hemodialysis, and rate of procedures to restore or to maintain patency. RESULTS: There was no significant difference in the risk of primary patency loss with vonapanitase 10 µg or 30 µg vs placebo. When seven initial patency loss events related to cephalic arch and central vein balloon angioplasty were excluded, the risk of patency loss was reduced with vonapanitase overall (hazard ratio [HR], 0.63; P = .049) and 30 µg (HR, 0.51; P = .03). In patients with radiocephalic fistulas (n = 67), the risks of primary and secondary patency loss were reduced with 30 µg (HR, 0.37 [P = .02] and 0.24 [P = .046], respectively). The rate of procedures to restore or to maintain fistula patency was reduced with 30 µg vs placebo (0.23 vs 0.72 procedure days/patient/year; P = .03) and also reduced in patients with radiocephalic fistulas with 30 µg vs placebo (0.17 vs 0.85 procedure days/patient/year; P = .048). CONCLUSIONS: In this study, vonapanitase did not significantly improve primary patency in the primary analysis but did significantly improve primary patency in an analysis that excluded patency loss due to cephalic arch and central vein balloon angioplasty. In patients with radiocephalic fistulas, 30 µg significantly improved primary and secondary patency. Vonapanitase 30 µg decreased the rate of procedures to restore or to maintain patency in the analysis that included all patients and in the subset with radiocephalic fistulas.

A national survey of disease-specific knowledge in patients with an abdominal aortic aneurysm.

OBJECTIVE: Patient education is a fundamental responsibility of medical providers caring for patients with abdominal aortic aneurysms (AAA). We sought to evaluate and quantify AAA-specific knowledge in patients under AAA surveillance and in patients who have undergone AAA repair. METHODS: In 2013, 1373 patients from 6 U.S. institutions were mailed an AAA-specific quality of life and knowledge survey. Of these patients, 1008 (73%) returned completed surveys for analysis. The knowledge domain of the survey consisted of nine questions. An AAA knowledge score was calculated for each patient based on the proportion of questions answered correctly. The score was then compared according to sex, race, and education level. Surveillance and repaired patients were also compared. RESULTS: Among 1008 survey respondents, 351 were under AAA surveillance and 657 had AAA repair (endovascular repair, 414; open, 179; unknown, 64). The majority of patients (85%) reported that their "doctor's office" was their most important source of AAA information. The "Internet" and "other written materials" were each reported as the most important source of information 5% of the time with "other patients" reported 2% of the time. The mean AAA knowledge score was 47% (range 0%-100%; standard deviation, 23%) with a broad variation in percentage correct between questions. Thirty-two percent of respondents did not know that larger AAA size increases rupture risk, and 64% did not know that AAA runs in families. Only 15% of patients answered six or more of the nine questions correctly, and 23% of patients answered two or fewer questions correctly. AAA knowledge was significantly greater in men compared with women, whites compared with nonwhites, high school graduates compared with nongraduates, and surveillance compared with repaired patients. CONCLUSIONS: In a national survey of AAA-specific knowledge, patients demonstrated poor understanding of their condition. This may contribute to anxiety and uninformed decision making. The need for increased focus on education by vascular providers is a substantial unmet need.

Human type I pancreatic elastase treatment of arteriovenous fistulas in patients with chronic kidney disease.

OBJECTIVE: This study explored the safety and efficacy of recombinant type I pancreatic elastase (PRT-201) topically applied once to the external surface of an arteriovenous fistula. METHODS: This was a randomized, double-blind, placebo-controlled trial. Adults with kidney disease undergoing creation of a radiocephalic fistula (RCF) or brachiocephalic fistula were randomized to treatment with placebo (n = 51), PRT-201 at 10 µg (n = 51), or PRT-201 at 30 µg (n = 49). The primary efficacy measure was unassisted primary patency (PP) over 1 year. Secondary efficacy measures were secondary patency (SP), unassisted maturation by ultrasound interrogation, use for hemodialysis, and hemodynamically significant lumen stenosis. RESULTS: Median PP was 224 days for placebo and >365 days for the PRT-201 groups. At 1 year, 45%, 54%, and 53% of placebo, 10-µg, and 30-µg patients retained PP. The risk of PP loss was nonsignificantly reduced for 10 µg (hazard ratio [HR], 0.69; P = .19) and 30 µg (HR, 0.67; P = .17) vs placebo. In the subset (44% of patients) with a RCF, the median PP was 125 days for placebo and >365 days for the PRT-201 groups. At 1 year, 31%, 50%, and 63% of placebo, 10-µg, and 30-µg RCFs retained PP. The risk of RCF PP loss was nonsignificantly reduced by 10 µg (HR, 0.59; P = .18) and significantly reduced by 30 µg (HR, 0.37; P = .02) vs placebo. At 1 year, 77%, 81%, and 83% of placebo, 10-µg, and 30-µg patients retained SP. The risk of SP loss was nonsignificantly reduced for 10 µg (HR, 0.79; P = .61) and 30 µg (HR, 0.76; P = .55) vs placebo. In the subset with RCFs, 65%, 82%, and 90% of placebo, 10-µg, and 30-µg patients retained SP at 1 year. The risk of RCF SP loss was nonsignificantly reduced for 10 µg (HR, 0.45; P = .19) and 30 µg (HR, 0.27; P = .08) vs placebo. At month 3, 67%, 87% (P = .03), and 92% (P < .01) of the placebo, 10-µg, and 30-µg group fistulas had unassisted maturation by ultrasound interrogation. At month 3 in the subset with an RCF, 47%, 74% (P = .17), and 93% (P < .01) of placebo, 10-µg, and 30-µg group fistulas had unassisted maturation by ultrasound interrogation. Adverse event reports were not meaningfully different between groups. CONCLUSIONS: PRT-201 appeared safe. The primary efficacy end point was not met. However, both PRT-201 doses were associated with improved unassisted maturation. The 30-µg dose was associated with increased PP in the subset with RCF.