The aim of the study is to evaluate the novel use of adrenal radiofrequency ablation on a prospective cohort of patients with primary aldosteronism and unilateral adrenal adenoma concerning the efficacy on blood pressure control. The safety of the procedure is one of the secondary outcomes.

The prevalence of hypertension dramatically increased. Although most cases of hypertension are idiopathic, some cases have an identifiable cause. Primary Aldosteronism (PA) is the most common cause of secondary hypertension and can be cured by surgery if PA is due to unilateral unique adrenal adenoma. Then this cause is worth identifying it. The surgery despite its minimally invasive nature is limited by the need for general anesthesia, the risk of vascular or visceral injuries, hematomas and all the adrenal gland is mostly removed. Imaged-guided percutaneous adrenal radiofrequency ablation (ARF) offers a less invasive alternative therapeutic option. This local therapy is employed to treat solid neoplasms whereas its application on functional adrenal adenoma is less documented and only a few case series with limited sample size are published. The impact on blood pressure control is not clearly reported. ARF ablation works by delivering a high-frequency alternating current through a needle electrode. An ionic agitation occurs and generates frictional heat for cell destruction at a predictable temperature and volume. Patients with a conventional documented PA due to unilateral adrenal nod who consented to the study were hospitalized. Patients with PA due to an aldosterone-producing adenoma are included in the study.

Inclusion Criteria:

• hypertension confirmed with ambulatory blood pressure monitoring
• primary aldosteronism demonstrated by hormonal assays: active renin (pg/ml) or plasma renin activity (ng/ml/h) and plasma aldosterone measured twice at baseline after an overnight fast, in sitting or recumbent position
• selective adrenal venous sampling after 40 years of age
• unilateral adrenal nod on CT scan <4cm
• adrenal radiofrequency ablation procedure of judged technically possible by radiologists

Exclusion Criteria:

• bilateral adrenal nods
• primary aldosteronism due to bilateral adrenal hyperplasia or macronodular hyperplasia
• lack of documented primary aldosteronism
• maximum tumor diameter greater than 4 cm
• Cushing syndrome or Pheochromocytoma
• when adrenal venous sampling is refused by the patient
• coagulopathy
• pregnant women
• patient with potentially inaccessible nodule