Renal denervation (RDN) provides a significant reduction in blood pressure in patients with uncontrolled hypertension despite lifestyle changes and drug treatment. Renal denervation decreases blood pressure by affecting the sympathetic system. Alcohol-mediated RND is a new neural ablation method performed by applying dehydrated alcohol to the perivascular area with a catheter.

The aim of the Target BP I study was to examine the efficacy and safety of alcohol-mediated RND treatment in the presence of antihypertensive medication.

It is a prospective, international, sham-controlled (only diagnostic renal angiography group), randomised, double-blind study. Patients with office systolic blood pressure (SBP) ?150 and ?180 mmHg, office diastolic blood pressure (DBP) ?90 mmHg and mean 24-hour ambulatory SBP ?135 and ?170 mmHg despite using 2-5 antihypertensive drugs were included in the study. Patients with secondary hypertension, type 1 DM and uncontrolled type 2 DM, GF<45ml/min, history of myocardial infarction, unstable angina, history of stroke and transient ischaemic attack within 6 months, NYHA 3-4 or EF<30 heart failure and persistent AF were excluded. The primary endpoint of the study was defined as the change in mean 24-hour ambulatory SBP from baseline to 3 months after the procedure. The secondary efficacy endpoint was defined as the change in mean office SBP from baseline to 3 months after the procedure. The safety endpoint was defined as the occurrence of major adverse events 30 days post-procedure and renal artery patency at 6 months.

Total of 301 patients were randomised 1:1 to alcohol-mediated RND (n=148) and sham control (n=153) procedures. The mean follow-up period was 6 months. Most patients were male (RDN 113 [76.4%] and sham control groups 111 [72.5%]), and the mean age for the entire study population was 57 years. There was no significant difference between baseline 24-hour ambulatory SBP-DBP and office SBP-DBP between the two groups. The primary efficacy endpoint, 24-hour ambulatory SBP reduction from baseline to 3 months, was more pronounced in the RND group (-10.0 ± 14.2 versus -6.8 ± 12.1 mmHg), with a statistically significant difference (-3.2 mmHg, 95% CI -6.3, 0.0; P=0.0487). There was no significant difference in 24-hour ambulatory DBP and office SBP change between the two groups. There was 1 (0.7%) hypertensive crisis in the RDN group, while most adverse events were related to hypotension requiring intervention or medication change (6 patients, 4.0%). At day 30, the rate of major adverse events was 4.7% in the RDN group. None occurred in the sham control group (P=0.007). At 6 months, the sum of major adverse events was similar in the two groups (5.3% RDN vs. 4.0% sham control, P=0.224).

Alcohol-mediated RDN produced a modest but significant reduction in 24-hour ambulatory SBP at 3-month follow-up. Results were consistent across both day/night ABPM and prespecified subgroups. No significant difference in office blood pressure was observed between groups.

The results of the Target BP I study showed that among patients with resistant hypertension, renal denervation was associated with a modest improvement in blood pressure control. Long-term follow-up results of the study will be useful in evaluating the efficacy of alcohol-mediated RND in the treatment of resistant hypertension.