Primary Hyperaldosteronism

Question 1

Primary Hyperaldosteronism:
Secondary hypertension causes to consider?

Answer 1

OSA - sleep study
Pheochromocytoma - 24hr metanephrines
Renal artery Stenosis - CTA/USS KUB
Hyperaldosteronism - Aldosterone Renin Ratio (ARR)

Question 2

Primary Hyperaldosteronism:
When specifically to consider hyperaldosteronism?

Answer 2

-BP regularly above 150/100
-BP >140/90 resistant to 3 drugs (including a diuretic),
-BP <140/90 on 4 or more antihypertensives
-HTN and spontaneous or diuretic-induced hypokalaemia
-HTN and adrenal incidentaloma
-HTN and sleep apnoea
-HTN and FHx of early-onset HTN or CVA <40 years
-HTN in first-degree relatives of a patient with primary aldosteronism

Question 3

Primary Hyperaldosteronism:
Optimal conditions to be set up for effective testing?

Answer 3

1) on no antihypertensives yet
OR
Remove and/or replace the following in order of preference
1. diuretics
2. ACEi, ARBs, dihydropyridine CCBs (eg amlodipine)
o not cease ACEi/ARB IF CCF with EF <50%
3. non selective BBs

2) normokalaemia with or without replacement

**Testing should not occur for at least 6 weeks of the above conditions being met.

**The ARR should be performed at least 2 hours after waking in the morning

Question 4

Primary Hyperaldosteronism:
Medication alternatives to allow for BP control prior to screening for hyperaldosteronism?

Answer 4

SR Verapamil 180 - 240mg daily
-be wary of bradycardia with higher doses

Moxonidine 200microgs - 400microgs, nocte - BD
-dry mouth, dizziness, lethargy possible
-contraindicated in CCF, bradycardia and AV blocks

Prazosin up to 5mg TDS
-avoid if pending cataract surgery (floppy iris syndrome)
-similar side effects to moxonidine can also cause urinary or faecal incontinence

Hydralazine up to 50mg TDS
-flushing, headache, dizziness, palpitations can occur