Effect of extracorporeal shock wave lithotripsy and ursodeoxycholic acid on gallbladder motility

Extracorporeal shock wave lithotripsy and dissolution agents are useful nonsurgical therapies for gallstones. Their effect on gallbladder emptying is unclear. We evaluated emptying by ultrasonography before and after lithotripsy in 50 patients on ursodeoxycholic acid or placebo and in nine controls. At baseline, patients had normal (68.8 +/- 3.2%) or delayed emptying (14.5 +/- 3.3%). In a subset of 24 patients, lithotripsy increased fasting volume (26.6 +/- 3.0 to 43.8 +/- 5.0 ml, P < 0.005), postprandial volume (11.3 +/- 3.1 ml to 22.9 +/- 3.0 ml, P < 0.05), and decreased ejection fraction (70.0 +/- 4.1% to 42.7 +/- 6.0%, P < 0.0005). There was an inverse linear correlation between power and ejection fraction, r = -0.43, P < 0.005. Ursodeoxycholic acid increased fasting (23.3 +/- 2.2 ml to 36.7 +/- 4.6 ml, P < 0.005) and postprandial volume (11.1 +/- 1.8 to 17.6 +/- 2.5, P < 0.005). Treatment with ursodeoxycholic acid resulted in a greater decrease in fragment size compared to placebo after lithotripsy in patients with fragment size greater than 6 mm. In conclusion, both lithotripsy and ursodeoxycholic acid have an effect on gallbladder emptying.