Purpose: To report a prospective study evaluating the long-term impact of stent-supported angioplasty on renal function and blood pressure control.
Methods: In a 6-year period, 456 hemodynamically significant de novo renal artery stenoses > or =70% were treated in 340 consecutive hypertensive patients (223 men; mean age 66+/-10 years, range 44-84) with or without impaired renal function. Baseline data on serum creatinine (sCr), intrarenal resistance index, ambulatory 24-hour blood pressure monitoring, and documentation of the number and dose of antihypertensive drugs were compared to values obtained during follow-up. The primary endpoint was a 10% decrease in sCr; the glomerular filtration rate and changes in blood pressure control were additional outcome measures.
Results: During a mean follow-up of 34+/-20 months, sCr decreased significantly from 1.45+/-0.87 to 1.39+/-0.73 mg/dL (p=0.048). In 34% of the patients, sCr decreased >10%, 39% were unchanged, and 27% had an increase >10%. Glomerular filtration rate increased from 59+/-26 to 62+/-26 mL/min/1.73 m(2) (p=0.6). Systolic, diastolic, and mean blood pressure measurements significantly improved immediately after the intervention (132/72/93 versus 144/79/102 mmHg at baseline, p<0.0001) and remained improved during follow-up (p<0.0001). Blood pressure control was improved in 46%, unchanged in 43%, and deteriorated in 11%. Baseline sCr, bilateral intervention, percent diameter stenosis, and 3-vessel coronary disease were independent predictors of improved renal function during follow-up; the number of antihypertensive drugs taken before the intervention predicted improved blood pressure control.
Conclusions: Stent-supported angioplasty of renal artery stenoses preserves renal function and improves blood pressure control in a broader spectrum of patients than previously thought.