Blood pressure changes after catheter-based renal denervation are related to reductions in total peripheral resistance.

ABSTRACT

BACKGROUND: Renal denervation (RDN) can reduce sympathetic activity and blood pressure (BP) in patients with uncontrolled hypertension. The exact mechanisms by which RDN results in BP reductions are yet not fully established. METHODS AND RESULTS: This study investigated the effects of RDN on office BP, 24-h ambulatory BP, noninvasive 10-min beat-to-beat digital pulse wave analysis, total peripheral resistance (TPR), cardiac output, and plasma renin and aldosterone serum concentrations in 30 patients with resistant hypertension. Adherence to antihypertensive drugs was assessed by liquid chromatography high-resolution tandem mass spectrometry analysis in plasma and urine at baseline and at 6 month. RDN significantly reduced office BP, beat-to-beat BP, and 24-h ambulatory BP by 19/6 (P = 0.021/P = 0.012), 12/7 (P = 0.005/P = 0.005), and 10/5  mmHg (P = 0.001/P = 0.049) at 6 months, respectively. TPR decreased from 1696 to 1377  dyn × s/cm (-19%; P = 0.027). This reduction was not associated with significant changes in cardiac output. The changes in office, ambulatory, and beat-to-beat BP correlated with the reductions of TPR. Adherence to antihypertensive treatment remained unchanged during the study period (84.7% at baseline, 83.6% at 6 months, P = 0.782). CONCLUSION: RDN reduced office BP, beat-to-beat BP, and 24-h ambulatory BP in patients with resistant hypertension after 6 months. The BP changes were associated with reductions in peripheral resistance, whereas cardiac output, plasma renin, and aldosterone levels remained unchanged. The observed effects were not explained by an increased intake of antihypertensive medications.