Primary aldosteronism (PA) is increasingly recognised as the most common endocrine cause of hypertension, with a 14% prevalence described in treatment-naïve hypertensive patients (Libianto 2022 MJA). PA is surgically curable if caused by the unilateral subtype. Accurate subtyping requires adrenal vein sampling (AVS), a technically challenging and time-consuming procedure. Anecdotal evidence suggests limited AVS availability around Australia with heterogenous test protocols and long waiting lists, during which time patients may accrue morbidity from aldosterone excess.
The objective of this study was to describe the current AVS landscape in Australia and identify existing gaps. Endocrine Unit Heads across Australia were invited to complete a survey exploring AVS access and methodology.
Of 46 unit heads contacted, 42 responded (91%) from all states. AVS was provided at 22/42 sites (52%), concentrated in Victoria, NSW and Queensland. One AVS centre was identified in Tasmania, WA and ACT, and none in the Northern Territory. Over half the centres performed ≤10 procedures/year from 2018-2021, and only 1 site consistently performed >50 procedures/year. The survey revealed significant variation in AVS methodology (including cannulation timing, ACTH stimulation and rapid cortisol assay use) and cut-offs for AVS interpretation (Table 1). Reported success of adrenal vein cannulation varied from 50-100% (mean 83%, median 90%), with greater success in centres with dedicated interventional radiologists and higher volume.
With hypertension affecting 34% of Australian adults (~6.8 million) and PA anticipated to affect 14% of hypertensive people, it is apparent that demand for AVS exceeds current availability. Variation in AVS protocols is likely to negatively impact efforts to address this gap. Protocol harmonisation may improve the consistency of success and allow standardized interpretation of results.
A survey of radiologists performing AVS is underway to complement existing data and enable formation of a working group to optimise AVS access and performance around Australia.