High incidence of secondary hypertension in patients referred for renal denervation – the Copenhagen experience

Abstract

Percutaneous renal denervation is a new treatment option for patients with resistant hypertension and little is known about the eligibility of patients referred. 100 consecutive patients were referred for renal denervation from March 2011 through September 2012. Clinical data were prospectively extracted from letters and documents from referring clinics and from our physical examination. Of the 100 patients included, 68 were men and the mean age was 60 (± 12) years. Office blood pressure was 176 (± 28)/99 (± 19) mmHg and 24-h ambulatory blood pressure 156 (± 20)/88 (± 13) mmHg. The mean number of antihypertensive agents was 4.0 (± 1.6). Nearly four-fifths (82%) of the patients were categorized as having resistant hypertension based on the criteria stated by The American Heart Association's stated criteria. Nine patients declined interest in renal denervation before completing the clinical workup program. Thus, 91 patients were screened, and of those 51 were found to be candidates for renal denervation. Forty patients were not candidates, of which secondary hypertension was the most common cause (n = 10). Only 51% of patients referred for renal denervation were eligible for treatment. The prevalence of secondary hypertension was 10% of the referred population. Secondary hypertension should therefore be considered in the evaluation of candidates for renal denervation.

Renal denervation

“…In a specialist tertiary referral clinic in France only 1.2% of 1209 patients referred to a oneday admission clinical work up for hypertension were suitable for RDN [44]. By contrast, a study of 11 expert centers participating in the European network coordinating research on renal denervation in treatment-resistant hypertension [45] found that 42.5% of patients were eligible for RDN, using the HTN-2 criteria, which is similar to our [46] and other findings [47].…”

“…The prevalence of secondary hypertension among patients with apparent resistant hypertension will vary depending on the clinical setting of referring clinics. RDN treatment of patients with secondary hypertension may indeed constitute a significant clinical problem since around 10% of patients specifically referred for RDN were diagnosed with secondary hypertension after a comprehensive diagnostic work up [46,47].…”

Screening for non-adherence to antihypertensive treatment as a part of the diagnostic pathway to renal denervation

“…Nearly all previous studies reported that a majority of patients assessed for suitability for renal denervation were non-eligible for this procedure. 13 , 14 , 15 , 16 , 26 However, screening for non-adherence to antihypertensive treatment was mentioned only in a minority of these studies. 13 , 26 One of the largest to date analysis conducted by Persu et al 13 attempted to exclude non-adherence to antihypertensive treatment in their multi-centre survey but only ≈50% of the participating sites included some form of testing for non-adherence to antihypertensive treatment and only 1 of 11 sites used an objective biochemical method of screening for presence of BP-lowering medications in body fluids.…”

“… 11 , 12 Many centres assessing patients for renal denervation developed their own eligibility criteria based on those published by European Society of Hypertension (ESH) and/or replicated the inclusion criteria for the Symplicity HTN-2 trial. 8 , 13 , 14 , 15 , 16 Based on those criteria only ≈10–50% of referred patients were eligible for renal denervation. 13 , 14 , 15 , 16 However, the reported rates may be a significant overestimation of the ultimate suitability for renal denervation, as systematic and objective screening for non-adherence to antihypertensive treatment (one of the most common form of pseudo-resistant hypertension) 17 , 18 , 19 was not a part of the evaluation process in a majority of the studies.…”

“… 8 , 13 , 14 , 15 , 16 Based on those criteria only ≈10–50% of referred patients were eligible for renal denervation. 13 , 14 , 15 , 16 However, the reported rates may be a significant overestimation of the ultimate suitability for renal denervation, as systematic and objective screening for non-adherence to antihypertensive treatment (one of the most common form of pseudo-resistant hypertension) 17 , 18 , 19 was not a part of the evaluation process in a majority of the studies. 13 , 14 , 15 , 16 …”