RESUMO
OBJECTIVES: The aim of this study was to assess whether the ratio of the mean infrarenal neck diameter to the suprarenal aortic diameter is a predictor for a durable proximal seal after endovascular aneurysm repair (EVAR). METHODS: A total of 439 patients who underwent elective EVAR between 2004 and 2018 in a single vascular referral center met our inclusion criteria. Ratios were calculated by dividing the mean infrarenal neck diameter by 4 different suprarenal aortic diameters. Patients who developed a late type 1A endoleak (n=20) or proximal neck dilatation mandating revision (n=8) were compared with the 411 patients without long-term proximal seal complications. RESULTS: Patients who developed a late type 1A endoleak had more frequently hypertension, a shorter infrarenal neck length, and a larger mean infrarenal neck diameter. The ratio of the mean infrarenal neck diameter to all 4 suprarenal aortic diameters was higher in the late type 1A endoleak group compared with the group without a late type 1A endoleak. Least absolute shrinkage and selection operator (LASSO) logistic regression identified a combination of 6 variables as the best combination to predict a late type 1A endoleak: presence of hypertension, increased mean infrarenal neck diameter, decreased aneurysm neck length, larger ratio of the mean infrarenal neck diameter to the aortic diameter proximal to the superior mesenteric artery (SMA), larger ratio of the mean infrarenal neck diameter to the aortic diameter proximal to the upper renal artery, and increased ß-angle. Of these, based on both the univariate area under the curve (AUC) and optimal LASSO model restricted to a single predictor, the ratio of the mean infrarenal neck diameter to the aortic diameter proximal to the SMA (AUC, 0.770; cutoff value, 0.997) was considered the best prognostic variable. CONCLUSION: The ratio of the mean infrarenal neck diameter to the aortic diameter proximal to the SMA is a good predictor for a late type 1A endoleak. Patients with mean infrarenal neck diameter larger than the diameter proximal to the SMA (ratio >1) are at risk for a late type 1A endoleak. CLINICAL IMPACT: In this single-center, retrospective cohort study, we found that the ratio of the mean infrarenal neck diameter to the aortic diameter proximal to the SMA is a good predictor for a late type 1A endoleak. We conclude that the suprarenal diameter must be taken into account before assessing endovascular aortic aneurysm repair eligibility. Patients with a ratio >1 may not be the best candidates for a durable result after EVAR and may be better off with fenestrated EVAR or open repair.
RESUMO
PURPOSE: The purpose of the study is to ascertain endovascular aneurysm repair (EVAR) suitability in relation to stent-graft-specific instructions for use (IFU) in patients with a ruptured abdominal aortic aneurysm (RAAA). MATERIALS AND METHODS: Using the preoperative computed tomography angiography (CTA), the aortic morphology of patients undergoing surgical repair of a RAAA in 2 Dutch hospitals between January 2014 and December 2019 was retrospectively assessed. Three-dimensional and central luminal line reconstructions were used. Anatomical suitability was defined according to the IFU of the stent graft system used. RESULTS: Of 128 included patients, 112 (88%) were men and the mean age was 74.1 (SD=7.6) years. Anatomy within IFU for EVAR was present in 31 patients (24%). Overall, 94 patients (73%) were treated with open surgical repair (OSR) and 34 patients (27%) were treated with EVAR. Anatomy within IFU was present in 15 OSR patients (16%) and 16 EVAR patients (47%). In patients with anatomy outside of IFU, 90% (87/97) had unsuitable neck anatomy and 64% (62/97) had insufficient neck length. An unsuitable distal iliac landing zone was observed in 35 patients. Perioperative mortality was 27% (34/128), with no difference between OSR and EVAR (25/94 vs 9/34; p=0.989). CONCLUSION: Most RAAA patients in this series did not have aortic anatomy within IFU for EVAR, mainly due to insufficient neck length. However, whether anatomy outside of IFU equates to unsuitability for EVAR in an emergency setting remains a matter of debate and warrants further research. CLINICAL IMPACT: The treatment of a ruptured abdominal aortic aneurysm can consist of endovascular repair or open repair. Retrospective anatomical assessment shows that most patients do not have anatomy inside the instructions for use for endovascular aneurysm repair, mainly due to insufficient neck length. Whether anatomy outside the instructions for use equates unsuitability for endovascular aneurysm repair remains a matter of debate.