BNP Level Prior to Renal Artery Stenting Does Not Predict BP Outcomes
Brain natriuretic peptide (BNP), a substance secreted by the heart that is associated with congestive heart failure and renal failure, does not predict reduction in systolic blood pressure (BP) in patients treated with renal artery stenting, according to results from the HERCULES trial.
The trial is a prospective, multicenter study of renal stenting in patients who have blockages in their renal arteries. The study reviewed outcomes for 202 patients (241 lesions) with uncontrolled hypertension who were treated with a renal artery stent between August 2007 and October 2009.
The nine-month restenosis rate, which was the study's primary endpoint, was 10.5%. With respect to secondary endpoints, systolic BP decreased significantly after stenting, with no change in medication requirements. Mean BNP levels remained elevated after one month. The researchers found no evidence of a correlation between elevated pre-treatment BNP levels and SBP reductions at follow-up. They measured BNP prior to treatment, at 24 hours post-treatment and then again 30 days later.
“The clinical results are promising, as we found very low restenosis rates and a significant drop in blood pressure following renal artery stenting,” said Michael R. Jaff, DO, Medical Director of the Vascular Center at Massachusetts General Hospital in Boston. “One goal of the study was to identify a means to predict which patients will have the best outcome after renal artery stenting. No correlation was found between pre-treatment BNP levels and SBP response, and patients with the best results did not have a significant reduction in BNP levels. So, our results show the search must continue for the best means to predict how patient will fare after renal artery stenting.”
Dr. Jaff presented these latest findings from the HERCULES Trial on May 5 at the Society for Cardiovascular Angiography and Interventions 2011 Scientific Sessions in Baltimore.