Evaluation of Renal Denervation by 24-Hour Ambulatory Blood Pressure and Quantified Antihypertensive Medication

Background: Previous studies of renal denervation (RDN) have mainly focused on the effect on office blood pressure (BP) and number of antihypertensive drugs although these are known as sub-optimal endpoints. Aim: The aim of this study was to evaluate the effect of RDN by combining 24-hour ambulatory blood pressure (ABP) measurements and quantified antihypertensive medication at 12 months after RDN. Methods: Fifty-one patients (71% men, mean age 56 years) with resistant hypertension were treated with RDN. Office BP and ABP were measured at baseline and 6 and 12 months after RDN. Concomitantly the administration of antihypertensive drugs was assessed by their total defined daily dose (DDD). Results are presented as mean values ( ± SD)). Results: The change in daytime systolic ABP at 6 and 12 months was -8.6 (22.5) (P=0.01) and -4.2 (22.3) mmHg (P=NS). Quantified antihypertensive medication was assessed, and at 12 months after RDN there was no change in antihypertensive medication in 33% of patients using the DDD method versus 53% of patients using counts of number of antihypertensive drugs (NS). At 12 months after RDN a ≥5 mmHg reduction in MAP (24-hour ABP) was found in 36% of the patients in addition to an unchanged or reduced DDD, whereas this was seen in 42% of patients when number of antihypertensive drugs were used (NS). Conclusions: There was no effect of RDN on ABP after 12 months. We have presented a method that embraces both ABP and quantitative assessment of antihypertensive medication to evaluate RDN by combined ΔDDD/24-hour ΔMAP.