[11C]metomidate PET-CT versus adrenal vein sampling for diagnosing surgically curable primary aldosteronism: a prospective, within-patient trial

Abstract

Primary aldosteronism (PA) due to a unilateral aldosterone-producing adenoma is a common cause of hypertension. This can be cured, or greatly improved, by adrenal surgery. However, the invasive nature of the standard pre-surgical investigation contributes to fewer than 1% of patients with PA being offered the chance of a cure. The primary objective of our prospective study of 143 patients with PA (NCT02945904) was to compare the accuracy of a non-invasive test, [11C]metomidate positron emission tomography computed tomography (MTO) scanning, with adrenal vein sampling (AVS) in predicting the biochemical remission of PA and the resolution of hypertension after surgery. A total of 128 patients reached 6- to 9-month follow-up, with 78 (61%) treated surgically and 50 (39%) managed medically. Of the 78 patients receiving surgery, 77 achieved one or more PA surgical outcome criterion for success. The accuracies of MTO at predicting biochemical and clinical success following adrenalectomy were, respectively, 72.7 and 65.4%. For AVS, the accuracies were 63.6 and 61.5%. MTO was not significantly superior, but the differences of 9.1% (95% confidence interval = −6.5 to 24.1%) and 3.8% (95% confidence interval = −11.9 to 9.4) lay within the pre-specified −17% margin for non-inferiority (P = 0.00055 and P = 0.0077, respectively). Of 24 serious adverse events, none was considered related to either investigation and 22 were fully resolved. MTO enables non-invasive diagnosis of unilateral PA.

Primary Aldosteronism and Drug Resistant Hypertension: A “Chicken-Egg” Story

“…AVS is technically demanding, not feasible for all patients, and not available at all centers. For these reasons, attempts were made to overcome this procedure, such as using PET-CT [60][61][62][63][64][65][66][67][68][69] or only CT-based management. The Spartacus randomized clinical trial claimed equivalence of CT and AVS-based strategy [70].…”

Investigation and assessment of adrenal incidentalomas

“…C-metomidate PET/CT is used as an adjunct/substitute for lateralisation of primary aldosteronism, when adrenal venous sampling has not been performed, technically challenging or the results inconclusive. 4…”

Decoding Hypertension Through Primary Aldosteronism

“…13 Fortunately, the application of newer functional imaging modalities such as carbon-11 metomidate positron emission computed tomography and galium-68 PentixaFor positron emission tomography 14 to noninvasively lateralize APAs is under investigation. 15 Our hope is that, as these specialized imaging studies become more widely available, distinguishing APAs from idiopathic adrenal hyperplasia will be more feasible for the clinician. However, the larger public health challenge of ensuring that all medical providers treating the pandemic of hypertension maintain a high clinical suspicion for PA remains.…”