Motivation: Yes, the blog is not dead. It has been moribund for a while under pressure from residency. Apologies.
A previous blog post here on July 2012 had considered kidney denervation for treatment of hypertension. Recently, there was a larger trial of this technique (SYMPLICITY HTN-3) was reported. So, should be all be considering this treatment for refractory hypertension?
Paper: Bhatt, D.L., Kandzari, D.E., O'Neill, W.W. et. al. "A Controlled Trial of Renal Denervation for Resistant Hypertension." NEJM (2014); 370: 1393-401
Method: Prospective blinded randomized sham-controlled trial in adult patients with severe resistant hypertension. Subjects were randomized in 2:1 ratio to undergo renal denervation or a sham procedure. Severe resistant hypertension was defined as three drugs at maximum doses. Primary endpoint was change in systolic blood pressure at six months.Of note, patients with renal artery stenosis were excluded.
Results:
Cohort: Total of 535 patients were randomized in this trial (364 to renal denervation group and 171 to sham procedure). The average age was about 57 years with roughly 60% of male patients. Baseline characteristics including body mass index, race, kidney disease, cardiovascular disease, and rate of smoking were not different between the two groups. On average, subjects took five antihypertensive medications.
Primary outcome: At six months, the intervention group had 14.13 mmHg decrease in SBP compared to 11.74 mmHg decrease in the sham group. This difference was not statistically significant.
Safety: There were five adverse effects in the intervention group compared to one in the sham group. There was no difference kidney function in the intervention group.
Discussion: This trial shows that renal denervation is not worth pursuing in the severely refractory hypertensive group of patients. The question remains why the therapy appeared so promising in the smaller trial but failed now. One possible reason is that in the smaller previous trial, the placebo and the intervention groups were not well matched while the two groups are well matched in this trial. While this trial did not have promising results, one wonders whether this same procedure might benefit patients with early hypertension who may still respond to renal denervation. However, for now, I would not recommend this therapy.
A previous blog post here on July 2012 had considered kidney denervation for treatment of hypertension. Recently, there was a larger trial of this technique (SYMPLICITY HTN-3) was reported. So, should be all be considering this treatment for refractory hypertension?
Paper: Bhatt, D.L., Kandzari, D.E., O'Neill, W.W. et. al. "A Controlled Trial of Renal Denervation for Resistant Hypertension." NEJM (2014); 370: 1393-401
Method: Prospective blinded randomized sham-controlled trial in adult patients with severe resistant hypertension. Subjects were randomized in 2:1 ratio to undergo renal denervation or a sham procedure. Severe resistant hypertension was defined as three drugs at maximum doses. Primary endpoint was change in systolic blood pressure at six months.Of note, patients with renal artery stenosis were excluded.
Results:
Cohort: Total of 535 patients were randomized in this trial (364 to renal denervation group and 171 to sham procedure). The average age was about 57 years with roughly 60% of male patients. Baseline characteristics including body mass index, race, kidney disease, cardiovascular disease, and rate of smoking were not different between the two groups. On average, subjects took five antihypertensive medications.
Primary outcome: At six months, the intervention group had 14.13 mmHg decrease in SBP compared to 11.74 mmHg decrease in the sham group. This difference was not statistically significant.
Safety: There were five adverse effects in the intervention group compared to one in the sham group. There was no difference kidney function in the intervention group.
Discussion: This trial shows that renal denervation is not worth pursuing in the severely refractory hypertensive group of patients. The question remains why the therapy appeared so promising in the smaller trial but failed now. One possible reason is that in the smaller previous trial, the placebo and the intervention groups were not well matched while the two groups are well matched in this trial. While this trial did not have promising results, one wonders whether this same procedure might benefit patients with early hypertension who may still respond to renal denervation. However, for now, I would not recommend this therapy.
