A Novel Iliac Morphology Score Predicts Procedural Mortality and Major Vascular Complication in Transfemoral Aortic Valve Replacement

Abstract

Vascular complications remain a challenge for the transfemoral approach to transcatheter aortic valve replacement (TAVR). The objective of this study was to develop a preoperative tool for prediction of major vascular complications of TAVR. A retrospective review was performed of patients who underwent transfemoral TAVR from 2011 to 2015 (N = 280). Iliofemoral arterial measurements were obtained with computed tomography angiography three-dimensional reconstructions, and the iliac morphology score (IMS) was created from these measurements. Vascular complications were defined by Valve Academic Research Consortium-2 criteria. Vascular complications were seen in 42 patients (15%). Major and minor vascular complication rates were 3.6% (n = 10) and 11.4% (n = 32), respectively. Fifty-three patients (19%) required vascular surgery consultation, with 31 (11%) requiring vascular interventions. IMS was calculated by computed tomography angiography analysis of iliac segments in 198 patients. Gender, iliac diameter and calcification, and access type were identified as predictors of major complications. IMS was composed of ipsilateral minimum iliac diameter and iliac calcifications based on area under the receiver operating characteristic curve analysis (P < .05; area under the curve = 0.82). Arterial size and calcification were classified from 0 to 3 on the basis of severity. Multivariate analysis identified gender and IMS as independent predictors of major complications. High-risk (IMS ≥5; n = 55) and low-risk (IMS <5; n = 139) groups were based on inflection point for specificity (73%) and sensitivity (83%). The high-risk group had smaller iliac diameters, areas, and luminal volumes and a higher rate of major vascular complications. Mortality rate was 10% in the high-score group and 1.4% in the low-score group. A patient risk score (PRS) was created to evaluate morphologic and patient factors that predict major complications. The PRS identified 59 patients as high risk (PRS ≥7). IMS of ipsilateral minimum iliac diameter plus iliac calcification is a predictor of major vascular complications and mortality. Alternative access in patients with high IMS may reduce major vascular complications and procedural mortality.