Bladder Wall Thickness - Ultrasound Measurement

A 68-year-old man with a 2-year history of progressive lower urinary tract symptoms (urinary frequency, nocturia, weak stream, and incomplete emptying) undergoes transabdominal ultrasound. His post-void residual is 180 mL and prostate volume is 75 cc. Bladder ultrasound in a well-distended state (350 mL) shows the structure marked **A** measuring 8.2 mm with diffuse uniform thickening and prominent muscular trabeculations creating a "Christmas tree" appearance. Which of the following is the most likely pathophysiological consequence of the thickening seen at **A**?