Age Factors Aged Aged, 80 and over Aortic Aneurysm, Abdominal--diagnostic imaging Blood Vessel Prosthesis Implantation--adverse effects Body Mass Index Chi-Square Distribution Conversion to Open Surgery--adverse effects Databases, Factual Endovascular Procedures--adverse effects Female Humans Logistic Models Male Middle Aged Multivariate Analysis Obesity--diagnosis Odds Ratio Postoperative Complications--etiology Protective Factors Racial Groups Retreatment Risk Factors Sex Factors Time Factors Treatment Outcome United States--epidemiology