What are the ideal metrics for assessing the quality of long-term stabilized “perfect” 24-h BP control after renal denervation?

A significant number of individuals being treated for hypertension still have uncontrolled blood pressure (BP). In Japan, renal denervation (RDN) is being introduced into clinical practice as an adjunctive treatment for hypertension that is uncontrolled despite adequate lifestyle changes and maximal antihypertensive drug therapy. The pivotal SPYRAL ON-MED trial showed that there was a significant reduction in trough office and nighttime ambulatory BP values in the RDN group compared with sham control group, although 24-h and daytime BP values were not significantly different between the two groups. The trough office BP measurement (taken before morning antihypertensive dosing) is similar to guideline recommendations for taking morning home BP before taking the morning antihypertensive drug dose. Recent guidelines recommend the measurement of nighttime BP because nighttime BP is a stronger predictor of cardiovascular event risk than daytime BP. It is particularly important to assess nighttime BP in medicated individuals with hypertension because the up- or down-titration of antihypertensive drug dosing is primarily based on office and daytime BPs in clinical practice. This means that there may be significant risk relating to nocturnal hypertension during longer follow-up. Because RDN results in persistent, “always-on” 24-h BP-lowering effects, the best BP metrics to assess the potential benefit of RDN are nighttime BP (determined using home or ambulatory BP monitoring) and morning BP (determined using home BP monitoring or morning trough office BP measurement). The variability of office, home, and ambulatory BP values is another important metric to assess the quality of RDN-related BP lowering. (Figure presented.)