Prospective study of the long-term effects of shock wave lithotripsy on renal function and blood pressure.

Purpose: We clarified the long-term effects of extracorporeal shock wave lithotripsy on renal function and blood pressure, and its relation to body mass index and type of lithotriptor.

Materials And Methods: A total of 100 patients with a single radiopaque renal stone 2 cm or less in length were followed for 18 to 57 months (mean 43.6 +/- 13.8) after being stone-free by extracorporeal shock wave lithotripsy monotherapy using 2 lithotriptors. Mean patient age was 47.9 +/- 9.1 years (range 23 to 66). Nuclear scintigraphy using (99m)technetium-mercaptoacetyltriglycine was done for all patients before extracorporeal shock wave lithotripsy, as well as at the last followup visit to estimate glomerular filtration rate, clearance and split renal function. Blood pressure measurements were recorded at admission and at each followup visit.

Results: Before extracorporeal shock wave lithotripsy treated side mean (99m)technetium-mercaptoacetyltriglycine clearance, glomerular filtration rate and split function were 146.22 +/- 59.48, 52.66 +/- 13.69 and 49.7 +/- 7.31, respectively. At the last followup visit they were 145.1 +/- 58.82 (p = 0.842), 54.85 +/- 15.75 (p = 0.114) and 49.96 +/- 8.68 (p = 0.577), respectively. Of 100 patients 18 were hypertensive before extracorporeal shock wave lithotripsy and 21 were hypertensive at the last followup visit. Mean diastolic blood pressure before extracorporeal shock wave lithotripsy was 80.2 +/- 6.2 vs 80.6 +/- 7.8 mm Hg (p = 0.674) at the end of followup. Mean systolic blood pressure before extracorporeal shock wave lithotripsy was 121.2 +/- 9 vs 121.55 +/- 10.2 mm Hg by the end of the study (p = 0.748). There were no statistically significant differences among body mass index groups or lithotriptor groups.

Conclusions: Extracorporeal shock wave lithotripsy is a safe procedure and has no significant long-term effects on renal function or blood pressure regardless of the type of machine used or body mass index.