Review Question - QID 215016

A 67-year-old man presents to clinic for a routine annual physical exam. He has no acute concerns he wishes to discuss this visit. His past medical history includes hypertension, hyperlipidemia, and type 2 diabetes mellitus. His medications include lisinopril, atorvastatin, and metformin. He does not drink alcohol but has smoked half a pack of cigarettes per day for the past 20 years. His temperature is 37.2°C (98.9°F), blood pressure is 137/92 mmHg, pulse is 89/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical examination reveals a pulsatile abdominal mass. Subsequently, an abdominal ultrasound and a computed tomography (CT) scan of the abdomen and pelvis are performed (Figure A). Which of the following characteristics of the abdominal aortic aneurysm (AAA) would prompt close monitoring with serial ultrasounds rather than surgical intervention?