Dual Imaging Enables Accurate Diagnosis in Primary Aldosteronism

Dual-modality imaging with ⁶⁸Ga-Pentixafor positron emission tomography/magnetic resonance (PET/MR) and ⁶⁸Ga-FAPI-04 PET/cardiovascular magnetic resonance (CMR) can serve as a comprehensive imaging approach, allowing accurate diagnosis and subtype classification and assessment of cardiovascular complications and monitoring of therapeutic responses, in individuals with primary aldosteronism, according to research presented at the 2025 Society of Nuclear Medicine and Molecular Imaging (SNMMI) Annual Meeting.

Primary aldosteronism is characterized by hypertension, hypokalemia, and multi-system damage, including cardiovascular disease and serious cardiac events.

“Precise diagnosis and assessment of cardiac issues is critical for patients with primary aldosteronism,” said investigator Jie Ding, MD, of the Department of Nuclear Medicine, Shanghai East Hospital, Tongji University, Shanghai, China, as reported by the SNMMI. “Our study evaluated the effectiveness of this dual-modality approach integrating adrenal and cardiac imaging in disease management.”

The researchers conducted a prospective study using ⁶⁸Ga-Pentixafor PET/MR adrenal imaging for disease subtype differentiation and ⁶⁸Ga-FAPI-04 PET/CMR myocardial imaging to evaluate the distribution and extent of myocardial damage in patients with primary aldosteronism.

 The study included 30 patients with primary aldosteronism and 15 patients with primary hypertension as a control group. All participants underwent dual-modality imaging. The investigators quantified and compared standardized uptake values (SUVs) of the adrenal glands and myocardium between the groups. A subset of patients with aldosterone-producing adenoma underwent follow-up ⁶⁸Ga-FAPI-04 PET/CMR imaging after adrenalectomy.

 Among the patients with primary aldosteronism, dual-modality imaging was able to differentiate disease subtypes with 50% of patients having aldosterone-producing adenoma, and 50% of patients having idiopathic hyperaldosteronism.

Patients with aldosterone-producing adenoma had significantly higher adrenal ⁶⁸Ga-Pentixafor SUV compared with patients with idiopathic hyperaldosteronism (10.5 vs 3.6; P<.001). The investigators saw no increased uptake of ⁶⁸Ga-FAPI-04 in adrenal nodules.

The study also successfully quantified myocardial fibrosis burden. On ⁶⁸Ga-FAPI-04 PET/CMR, the investigators detected myocardial FAPI uptake in 56.7% patients with primary aldosteronism, predominantly in the interventricular septum and right ventricular insertion points (SUV_max of 1.3±0.3) and the average for myocardial segments affected (2±1).

A higher prevalence of myocardial FAPI uptake was observed among patients with aldosterone-producing adenoma (73.3%) compared with those with idiopathic hyperaldosteronism (40.0%) and primary hypertension (13.3%).

Among four patients with aldosterone-producing adenoma who had preoperative myocardial FAPI uptake, follow-up imaging at 5 months post-adrenalectomy demonstrated decreased SUV (preoperative vs postoperative: 1.40 vs 1.13), and investigators observed no significant changes in late gadolinium enhancement on CMR.

“This work revolutionizes the management of primary aldosteronism by enabling precise diagnosis and subtype classification, evaluating cardiovascular complications, and tracking treatment responses,” said Dr Ding. “Altogether, it offers essential insights for guiding personalized therapy.”