Percutaneous Management of Atherosclerotic Renovascular Disease

Background: The value of percutaneous renal artery intervention for patients with atherosclerotic renovascular disease (RVD) is uncertain. This retrospective review examines the early clinical response to percutaneous renal artery angioplasty with primary stenting (RA-PTAS) with and without distal embolic protection for patients with atherosclerotic RVD.
Methods: From October 2003 to June 2007, 105 patients (126 procedures) underwent RA-PTAS at our center. A subgroup of 86 consecutive patients (93 procedures; 44 women; mean age: 69±10 years) with hypertension and atherosclerotic RVD form the basis of this review. Hypertension response was judged from pre- and postoperative blood pressure measurements and medication requirements. Estimated glomerular filtration rate (EGFR) was calculated from serum creatinine and a >20% change in EGFR was considered significant. Both hypertension and renal function response were assessed at least 3 weeks after RA-PTAS (mean follow-up: 15 weeks). Multivariable regression analysis was used to examine associations between blood pressure and renal function responses to RA-PTAS and select clinical variables.
Results: 79 patients underwent unilateral and 7 patients underwent staged bilateral RA-PTAS. All patients had hypertension (mean BP: 161/79 mmHg; mean number antihypertensive agents: 3.3). Cardiac disease (63%), renal insufficiency (74%; defined as EGFR<60ml/min/m²and diabetes mellitus (28%) were prevalent. A mean RA diameter-reducing stenosis of 79% was treated with angioplasty and primary endoluminal stenting (mean stent diameter: 5.5mm; mean stent length: 16mm). In 85 procedures (91%) distal RA embolic protection was attempted with a commercially available balloon-tip wire resulting in complete embolic protection in 63 cases (74%). Embolic protection resulted in a mean warm renal ischemia time of 16+6 minutes. Assessed at least three weeks after surgery, intervention appeared to have a beneficial effect on hypertension (mean preoperative BP 161/79 versus postoperative 150/73 mmHG; P<0.01) and renal function (mean preoperative EGFR: 48±22 versus postoperative 51±22 ml/min/m²; P=0.06). Hypertension was considered cured or improved in 16% and unchanged in 84%. Twenty patients (28%) had improved renal function, 45 (63%) patients were unchanged, and 7 (10%) patients were worsened. At 12 months, hemodynamic recurrence by renal duplex sonography (RA peak systolic velocity >1.8m/s) was observed in 22 of 45 (49%) RA-PTAS procedures. Seven patients required repeat intervention for recurrence during follow-up. Multivariable analysis identified no independent parameters associated with hypertension response. However, preoperative EGFR and incomplete renal artery revascularization were independently associated with a lower postoperative EGFR during early follow-up.
Conclusions: Percutaneous RA-PTAS of atherosclerotic RVD provided modest blood pressure and renal function benefit in select patients. The rate of disease recurrence by renal duplex was high, though few patients had repeat intervention. Further prospective study of RA-PTAS is required to improve patient selection and clinical outcomes.