SPARTACUS: Subtyping Primary Aldosteronism: a Randomized Trial Comparing Adrenal Vein Sampling and Computed Tomography Scan.

Radboud University Medical Center

Status and phase: Completed; Phase 3

Conditions: Hyperaldosteronism

Treatments: Other: Ct-scan or adrenal vein sampling

Study type: Interventional

Funder types: Other

Identifiers

NCT01096654

avs-ct1

Details and patient eligibility

About

Rationale: Primary hyperaldosteronism (PA) is the most frequent form of secondary hypertension. In PA autonomous hypersecretion of aldosterone by one or both adrenal glands causes hypertension that is often refractory to treatment. PA is usually caused by either a unilateral aldosterone-producing (micro)adenoma (APA) or by bilateral adrenal hyperplasia (BAH). Distinction between APA and BAH is critical since the former is treated with the aim of cure by adrenalectomy, and the latter by mineralocorticoid receptor antagonists. This distinction can be made by adrenal vein sampling (AVS), as recommended by The Endocrine Society 2008 guideline or by CT-scanning, as is common practice in the Netherlands. AVS is invasive, demands great skill, and is expensive, while CT-scanning is non-invasive, easy and cheap, but might be less accurate. However, the advantage of AVS has never been demonstrated in prospective randomized studies. Here we propose to perform a prospective, randomized, multicenter study that compares effectiveness of AVS with effectiveness of CT-scanning for the diagnosis of PA subtype.

Objective: To assess the quantity of antihypertensive medication needed in order to normalize blood pressure in patients who have been managed for PA according to either AVS or CT-scan. Secondary objectives: to assess potassium, costs of management and quality of life.

Study design: Prospective, randomized trial in a multi-centre setting. Two hundred patients will be recruited within two years. Follow-up will be one year after (start of) treatment.

Study population: Adult patients with therapy-resistant hypertension, with or without hypokalemia, caused by PA.

Intervention: Patients will be randomized to undergo either adrenal CT-scanning or AVS (with pre-AVS adrenal CT-scanning for phlebography). The result of either of these tests will determine the course of action: adrenalectomy for adenoma or MRAs for bilateral hyperplasia.

Main study parameters/endpoints: The quantity of antihypertensive drugs patients are using to obtain target blood pressure, expressed in Daily Defined Dosages, is used as the main study parameter. There is no criterion standard for accuracy of the diagnosis of PA-subtype, but we assume that if treatment is based on a more accurate diagnosis, treatment is more effective. The most important secondary endpoints are the costs of the diagnostic course and long-term medical treatment and the quality of life as assessed by a validated questionnaire.

Enrollment: 200 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Legally capacitated;
• ≥ 18 years of age;
• Diagnosed with hypertension that is difficult to treat (blood pressure > 140/90 mmHg in spite of two antihypertensive drugs in adequate doses), or accompanied by hypokalemia, either spontaneous or induced by use of diuretics;
• patients must have a positive result on a sodium loading test (as recommended in the Endocrine Society Guideline), i.e. insufficient suppression of aldosterone.
• Cooperating patient who is willing to undergo adrenal surgery in case of an adenoma or lateralized aldosterone secretion, who is able to comply with the study protocol and who is willing to give written informed consent.

Exclusion criteria

• Unsuitability for or objection to undergo AVS, CT or adrenal surgery.(including pregnancy);
• Glucocorticoid remediable aldosteronism or adrenal carcinoma;
• Severe or terminal co-morbidity which seriously interferes with possible treatment or health related quality of life;
• Requirement of certain medication that interacts with the prescribed treatments in this protocol or that can cause hypertension as an important side-effect e.g. glucocorticoids. Patients will only be excluded as the medication cannot be stopped or altered.

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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200 participants in 2 patient groups

CT-scan

Active Comparator group

Description:

In this group treatment will be based on the outcome of the CT-scan only. Patients will be treated by adrenalectomy (Adx) if an unilateral lesion is visible on the CT-scan and the contralateral gland is normal. If bilateral lesions, bilateral enlargement or symmetric normal adrenal glands are present patients will be treated by the mineralocorticoid receptor antagonist (MRA)

Treatment:

Other: Ct-scan or adrenal vein sampling

Adrenal Vein Sampling

Active Comparator group

Description:

This group will be treated according to the results of the adrenal vein sampling only. Adrenal vein sampling will be performed under the continuous infusion of ACTH (adrenocorticotropic hormone). A cortisol ratio ≥ 3 between the adrenal vein and the inferior vena cava is set as the criterium for successful cannulation. The criterium for lateralization is a aldosterone/cortisol ratio ≥ 4 between the adrenal veins and a lower aldosterone/cortisol ratio in the contralateral adrenal vein than in the inferior vena cava. If AVS fails patients will be treated according to the CT-findings as described in the group with CT-scan only. Patients with a successful AVS will be treated by Adrenalectomy if unilateral production of aldosterone is shown. If no unilateral aldosterone production is present, i.e. the aldosterone/cortisol ratio is less than 4, patients will be treated by MRA.

Treatment:

Other: Ct-scan or adrenal vein sampling