[Renal sympathetic denervation for treatment of resistant hypertension]. / Ablação da atividade simpática renal para tratamento da hipertensão arterial resistente.

Hypertension is an important cardiovascular risk factor and although there have been many improvements in pharmacological treatment, a significant percentage of patients are still considered resistant. The authors describe two cases of radiofrequency renal sympathetic denervation that illustrate the feasibility of this new technique for the treatment of resistant hypertension. The procedure consists of the application of radiofrequency energy inside the renal arteries to ablate afferent and efferent sympathetic renal activity, which has been implicated in the pathophysiology of hypertension.

Renal denervation in patients with resistant hypertension: six-month results.

INTRODUCTION: Increased activation of the sympathetic nervous system plays a central role in the pathophysiology of hypertension (HTN). Catheter-based renal denervation (RDN) was recently developed for the treatment of resistant HTN. AIM: To assess the safety and efficacy of RDN for blood pressure (BP) reduction at six months in patients with resistant HTN. METHODS: In this prospective registry of patients with essential resistant HTN who underwent RDN between July 2011 and May 2013, the efficacy of RDN was defined as ≥ 10 mm Hg reduction in office systolic blood pressure (SBP) six months after the intervention. RESULTS: In a resistant HTN outpatient clinic, 177 consecutive patients were evaluated, of whom 34 underwent RDN (age 62.7 ± 7.6 years; 50.0% male). There were no vascular complications, either at the access site or in the renal arteries. Of the 22 patients with complete six-month follow-up, the response rate was 81.8% (n=18). The mean office SBP reduction was 22 mm Hg (174 ± 23 vs. 152 ± 22 mm Hg; p<0.001) and 9 mm Hg in diastolic BP (89 ± 16 vs. 80 ± 11 mm Hg; p=0.006). The number of antihypertensive drugs (5.5 ± 1.0 vs. 4.6 ± 1.1; p=0.010) and pharmacological classes (5.4 ± 0.7 vs. 4.6 ± 1.1; p=0.009) also decreased significantly. Of the 24-hour ambulatory BP monitoring and echocardiographic parameters analyzed, there were significant reductions in diastolic load (45 ± 29 vs. 27 ± 26%; p=0.049) and in left ventricular mass index (174 ± 56 vs. 158 ± 60 g/m(2); p=0.014). CONCLUSION: In this cohort of patients with resistant HTN, RDN was safe and effective, with a significant BP reduction at six-month follow-up.