Abstract 6188: Wide Pulse Pressure as a Predictor of Poor Outcome after Renal Angioplasty and Stenting
Background Renal artery stenosis is a common cause of secondary hypertension and ischemic renovascular disease. In a subgroup of patients, percutaneous angioplasty and stent placement has enabled patients to utilize less anti-hypertensive medications. Moreover, in selected patients with chronic kidney disease, revascularization has led to improved renal function. However, the specific patient population whom would most benefit from intervention is still under investigation.
Methods The association of baseline systolic, diastolic, and pulse pressures with outcomes of blood pressure and renal function was examined in 243 patients who underwent renal angioplasty and stent placement. Worsening renal function was defined as an increase in creatinine (Cr) of >25% or absolute >0.5mg/dl during 6 month follow-up as compared to baseline. Improvement in blood pressure was defined as change in systolic blood pressure (sbp) 20mmHg or dbp >10mmHg.
Results 170 patients (70%) had improvement or stabilization of their renal function compared to 73 patients (30%) whom developed worsening renal function during the follow-up period. The average pulse pressure prior to the procedure in patients with improvement or stabilization in renal function was 53.2 mmHg versus 107.4 mmHg (p<0.05) for those with poorer outcomes. Higher pulse pressures correlated with worsening renal function, (p value <0.001). Higher systolic (p value<0.05) and higher diastolic (p value<0.001) pressures also correlated with poorer outcome. Blood pressure improved in 150 (62%) patients, stabilized in 24 (10%) patients, and worsened in 69 (28%) patients during the follow-up period. The average pulse pressure prior to procedure was 47mmHg for those with improvement of blood pressure, 82 mmHg for those with stabilization of blood pressure, and 111mmHg for those with worsening blood pressure. The differences in pulse pressures were statistically significant with p value < 0.01 and ETA correlation of 0.93.
Conclusions Wider pulse pressure may reflect more advanced renal disease and distinguish patients less likely to benefit from revascularization.