Actualization: Radiofrequency Sympathetic Denervation of the Renal Arteries for Refractory Arterial Hypertension

PICHON RIVIERE, A.; AUGUSTOVSKI, F.; GARCIA MARTI, S.; ALCARAZ, A.; GLUJOVSKY, D.; LOPEZ, A.; REY-ARES, L.; BARDACH, A.; CIAPPONI, A; DEHESE, J

Documento de Evaluación de tecnologías Sanitarias

IECS

Año: 2013 p. 1 - 30

1668-2793

Hypertension (AH) has a global estimated burden of a thousand million cases, resulting in 7.5 million deaths yearly (12.8% of total deaths). In Argentina, hypertension has a prevalence of 34.8% in in subjects over 18 years old. Refractory hypertension (RAH) is refers to the failure to control blood pressure values after administering at least three drugs of different mechanism of action, including a diuretic. It is estimated that it represents 10% of the hypertensive population. For this group of patients, it is stated that radiofrequency sympathetic denervation/ablation of the renal artery (RSDRA) may reduce the adrenergic hyperactivity and thus improve blood pressure control.TechnologySympathetic hyperactivity plays a major role in the onset, progression and persistence of AH. RSDRA is a minimally invasive intervention that consists in introducing an electrode through a percutaneous catheter into a vein to the renal arteries and subsequent use of high-frequency alternate current to obtain a coagulative necrosis of the neural tissue. Its implementation requires angiography, patient sedation, local anesthesia and a well-trained medical team.PurposeTo assess the available evidence on the efficacy, safety and coverage related aspect regarding RSDRA use for refractory arterial hypertension.MethodsA bibliographic search was carried out on the main databases: DARE, NHS EED, on Internet general search engines, in health technology evaluation agencies and health sponsors. Priority was given to the inclusion of systematic reviews; controlled, randomized clinical trials (RCTs); health technology and economic assessments (HTAs), clinical practice guidelines (CPGs) and coverage policies of other health systems.ResultsA systematic review (SR), an additional RCT, three observational studies, two CPGs, five HTAs and one coverage policy document were included.One SR published in 2013 included a total of 683 patients in two RCTs, two case-control studies and 13 case-series. Both RCTs included belong to the Symplicity-II study and reported a decrease in blood pressure (BP) in the RSDRA group when compared with the standard care group. One of the RCTs included 37 subjects and was designed to measure specifically the response in relation to exercise. The other one was conducted in 52 subjects with an analysis after 6 months. As regards BP control, the first one reported a decrease of 31/9 mmHg in systolic/diastolic BP after 3 months in the intervention arm; and the second -28.1/-9.7 mmHg after 12 months (p <0.001). No significant changes were reported in the glomerular filtration rate values or in the creatinine levels at the end of the follow up period.One multicenter RCT, published in 2010 randomized 106 patients with RAH to RSDRA or to continue with the regular care. At month six, a decrease of 33/11 mmHg in SBP and DBP respectively, was observed in the RSDRA group whereas no changes were observed in the control group (p<0.01). Also, a decrease in the number of antihypertensive drugs was observed before six months (p=0.04). No severe procedure-related complications were reported.A multicenter cohort study including 153 patients, published in 2011, reported positive results in antihypertensive control in all the measurements carried out after the procedure, being the SBP decreased of 32 mmHg and DBP, 14 mmHg at 24 months of follow up. Three percent of the patients presented complications such as pseudo-aneurysm or renal dissection. Two case series identified showed similar results.The GCPs issued in 2012 by a panel of experts from the French Hypertension, Cardiology and Radiology Societies and another one by the British Hypertension, Interventional Cardiology and Interventional Radiology Societies conclude that the patients with RAH who adhered to drug schemes and with no treatable secondary causes might benefit from RSDRA.The Health Technology assessment agencies: NICE, CADTH, Xunta de Galicia, Swedish Agency and Australian Agency concluded that RSDRA is a technique with a low incidence of complications and is efficacious at short and middle term. The US health system, Medicare, stated that long-term studies are required to assess the existing evidence in order to recommend this procedure.The cost of RSDRA is approximately AR$80,000 (Argentina pesos/March, 2013), approximately USD15,700 (US dollars/ March, 2013).CONCLUSIONSThe evidence found was of moderate methodological quality. The use of RSDRA associated to the underlying medical treatment proved to be useful in reducing BP in RAH patients at short and middle term (up to 24 months). The procedure could be taken into account only in those RAH patients under treatment at the maximum tolerated doses and adequate adherence, who have failed with all previous measures and if carried out by highly-qualified professionals. Potential subgroups that might benefit could be patients with RAH and kidney failure, due to increase in their sympathetic activity. Long-term studies are required to further assess its indications as well as its morbidity and mortality.