From the SIR Residents and Fellows Section (RFS)

Teaching Topic: Clinical Outcomes following Percutaneous Radiofrequency Ablation of Unilateral Aldosterone-Producing Adenoma: Comparison with Adrenalectomy

Sarwar A, Brook OR, Vaidya A, Sacks AC, Sacks BA, Goldberg SN, Ahmed M, Faintuch S. Clinical outcomes following percutaneous radiofrequency ablation of unilateral aldosterone-producing adenoma: comparison with adrenalectomy. J Vasc Interv Radiol. 2016. 27: 961-7.

Click here for abstract

In this recent manuscript in JVIR, researchers at Beth Israel Deaconess Medical Center compared adrenal RFA with adrenalectomy in treating unilateral aldosterone-producing adenoma (APA). The study included 44 patients with confirmed unilateral APA. Twelve of 44 underwent RFA and 32/44 underwent adrenalectomy. Both RFA and adrenalectomy resulted in normokalemia and normotension in all patients. However, RFA patients had a shorter lenth of stay (0.6 +/- 0.8 d vs. 1.7 +/- 1.4 d) less intraoperative blood loss. In addition, the adrenalectomy patients had procedural complication in 5/32 (15%) versus 0/12 in the RFA group. The authors concluded that RFA has similar effectiveness to adrenalectomy in treating patients with APA with less complications and a shorter hospital stay.

Clinical Pearls

Primary Aldosteronism (PA) is the most common cause of secondary hypertension, with a reported prevalence of 4.3% in the general population with hypertension and >11% in patients referred to specialized centers. Clinical practice guidelines from the Endocrine Society recommend unilateral laparoscopic adrenalectomy for patients with documented unilateral PA.

What patient factors/characteristics have studies shown to be associated with surgical cure of hypertension secondary to PA?

Demographic factors show that a younger age population, females and those with a BMI < 25 kg/m2 have been associated with surgical cure of hypertensin secondary to PA. Other factors that studies have shown to be associated with surgical cure are fewer antihypertensive medications before the procedure and a higher preoperative blood pressure.

Morning Report Questions

What constitutes a cure of hypertension and what constitutes improvement in hypertension from adrenalectomy?

A cure of hypertension is defined as normotension without the use of antihypertensive medications. An improvement in hypertension is normotension on the same regimen of medications that the patient was on prior to the procedure or normotension on a reduced number of antihypertensive medications.

What does The Endocrine Society recommend as the gold standard for laterization of excess hormone production?

The Endocrine Society recommends adrenal venous sampling (AVS) as the gold standard for laterization of excess hormone production. Unilateral production of excess aldosterone is most commonly due to an aldosterone-producing adenoma (APA) or unilateral adrenal hyperplasia.

What were some of the key findings observed in adrenalectomy vs RF ablation of unilateral aldosterone-producing adenoma?

This study demonstrated that RF ablation can achieve clinical outcomes similar to adrenalectomy with lower procedural morbidity in treating patients with AVS-proven unilateral APA. It showed that the efficacy in treating APA was similar with both treatments reducing blood pressure, number of anti-hypertensive medications and both treatments also increasing the serum potassium levels without the need for potassium replacement.

Another important finding in this study was that patients undergoing RF ablation had a significantly higher incidence of intraprocedural hypertensive urgency compared with patients undergoing adrenalectomy. These episodes of hypertensive urgency in the RF group were short in duration (<15 minutes) and were easily reversed by intraprocedural medications without any reported clinical sequelae. This raises an important consideration for future RF ablation procedures such as possibly adding alpha-adrenergic antagonist before the procedure to minimize the catecholamine surges that may occur secondary to incidental ablation of normal adrenal medullary tissue.

Post Author:
Andrew Niekamp, MD
Diagnostic Radiology Resident, PGY-3
UT Houston