As of now, the modest overall benefits and high cost of RDN should be balanced with its potential risks. In particular, more than 20 cases of de novo renal artery stenosis have been reported after RDN,52 most of them after the announcement that Symplicity HTN-3 failed to meet its primary endpoint. RDN deserves further investigation but is not ready for clinical deployment and its use should be restricted to research protocols. Accordingly, in Germany, the insurances companies which were the first in Europe to reimburse the procedure have terminated their coverage, and even well-known proponents of the technique acknowledge that RDN “should be returned back to the academic arena”53 before further clinical deployment.
In a substantial proportion of patients, resistant hypertension may reflect resistance to taking medications rather than true treatment resistance.54 In this perspective, therapeutic drug monitoring may prove an effective strategy, not only for detecting poor drug adherence but also for improving blood pressure control. Indeed, when non-adherent patients are confronted with their low or undetectable drug levels and provided additional counselling to overcome barriers of adherence, blood pressure control improves considerably without intensification of therapy.55 Along the same lines, a recent analysis based on German data and life statistics showed that therapeutic drug monitoring is a cost-effective health care intervention in patients diagnosed with apparent drug-resistant hypertension, and this finding is valid for a wide range of patients, irrespective of age and sex.56 Even in truly resistant hypertensive patients with demonstrated drug adherence, blood pressure control may be achieved in a substantial proportion of patients by skilful drug treatment adjustment.33,38 While RDN deserves more in depth research, in the present state of knowledge, initiatives aiming at diagnosing and improving poor drug adherence56,57 and optimisation of drug treatment51 may prove much more cost-effective, both at the individual and public health level.