Significant nighttime blood pressure reductions after radiofrequency renal denervation in patients with uncontrolled hypertension: pooled analysis of the spyral htn trials

Objective: Elevated nighttime systolic blood pressure (SBP) is more strongly associated with risk for cardiovascular events than daytime or office SBP. We assessed whether radiofrequency renal denervation (RF RDN) reduces nighttime SBP, in addition to other times of the day. Design and method: We pooled data from patients with uncontrolled hypertension undergoing RF RDN using the latest-generation Spyral multi-electrode catheter, from the published, SPYRAL HTN-OFF and -ON MED clinical trials. Office and 24-ambulatory SBP were evaluated at baseline and at 12 months. Different time ranges were evaluated including nighttime (1am-6am), morning (7am-9am), and daytime (9am-9pm). The number of antihypertensive drugs and drug burden (determined by number of classes and prescribed dosage) from urinary drug testing, where available, was assessed at baseline and at 12 months. Results: Data from 388 patients undergoing RDN were pooled. Patients were 54±10yrs old, 26.8% female, BMI 31.3±6.0, 45.1% with >10yrs diagnosis of hypertension, 7.7% type 2 diabetes, 9.8% obstructive sleep apnea, 16.2% current smoker. The baseline nighttime SBP was 139±11mmHg, and 92.5% had nocturnal hypertension (BP greater than or equal to 120/70 mmHg). Patients took 1.0±1.2 antihypertensive drugs with drug burden of 1.6±3.1 at baseline. 12 months after RDN, 30.6% of patients no longer had nocturnal hypertension (p<0.0001). The overall 24-h ambulatory SBP reduced by -11.9±12.4mmHg, nighttime -10.8±15.4mmHg, morning -12.8±20.4mmHg, daytime -12.2±13.6mmHg, and office -17.7±15.4mmHg (Figure). Patients took 1.8±1.1 antihypertensive drugs with drug burden of 2.9±3.0 at 12 months. Conclusions: In this pooled cohort of RDN patients with uncontrolled hypertension, nocturnal hypertension was highly prevalent. RF RDN achieved clinically meaningful reductions throughout the 24-hr circadian cycle including the nighttime SBP, when CV risk is highest. RF RDN, in addition to pharmacotherapy, may help to reduce this risk.