Management of Patients with Primary Hyperaldosteronism and Indeterminate Adrenal Vein Sampling: A 10 Year Experience of the Cleveland Clinic

In patients with Primary Hyperaldosteronism (PA) who undergo Adrenal Vein Sampling (AVS), an Aldosterone to Cortisol Lateralization (ACL) ratio of 3 to 4 has been defined as indeterminate and clinical judgement recommended in determining surgical referral. However, minimal guidance is present over what clinical characteristics should be used in making this determination. We present here the clinical outcomes in our institution for patients with ACL between 3-4 over the last 10 years.

Methods:

A retrospective analysis of an AVS registry from October 2010 to January 2021 at Cleveland Clinic. ACL ratio and Contralateral Suppression Index (CSI) for 367 AVS procedures was calculated. Adult patients with selective AVS (based on current standard of care) and an ACL ratio between 3 and 4 were included in the final analysis. Clinical data were collected for each of the patients from before AVS and up to 6 months after adrenal surgery and/or AVS. Descriptive and comparative analysis were subsequently performed.

Results:

A total of 18 patients with indeterminate ACL were identified (4.9% of all AVS performed), 10 of whom underwent adrenalectomy and 8 were managed medically. The mean age was 59.3 [SD 13.3] with a long duration hypertension (13.6 years [SD 10.9]) and a mean of 3 anti-hypertensives [SD 1.4]. Eleven patients (61.1%) were on potassium supplements. Twelve patients (66.7%) had a unilateral adrenal lesion on CT scan. The overall mean ACL ratio was 3.5 [SD 0.32] with a mean CSI of 0.9 [SD 0.85]. Patients who were managed surgically had a statistically significant lower CSI (M 0.6 [SD 0.4] vs 1.2 [SD 1.1], p-value 0.09), and were more likely to have a unilateral CT adrenal abnormality (90% vs 37.5%, P-value 0.01). Up to 6 months after surgery, patients who underwent adrenalectomy had a lower number of anti-hypertensives (2.8 vs 1.9, P-value 0.009), with a non-statistically significant lower systolic and diastolic blood pressures (M144.1/89.9 vs 129.1/84.2 mmHg, p-value 0.07 and 0.056, respectively). At 6 months, 2/10 patients in the surgical group were able to come off all anti-hypertensives (vs 0/8 in the medical group).

Discussion/Conclusion:

We present here the Cleveland Clinic experience with patients with ACL ratio between 3 and 4 on AVS. Those who underwent surgery had a lower CSI and typically a unilateral adrenal lesion. Outcomes revealed trends towards improvement in blood pressure and lower mean number of anti-hypertensives in the surgical group compared with the medical group, suggesting that there may be benefit with adrenalectomy in certain individuals with an indeterminate ACL ratio.