Evaluation and Management of Resistant Hypertension

Primary Aldosteronism Screening

The European Society of Cardiology recommends screening all patients with resistant hypertension for primary aldosteronism, as it occurs in 11-20% of cases 2, 3
Additional screening indications include spontaneous or diuretic-induced hypokalemia, incidentally discovered adrenal mass, family history of early-onset hypertension, or stroke before age 40 2, 3
The American Heart Association recommends ordering plasma aldosterone-to-renin ratio (ARR) as the screening test of choice 2, 3
The most commonly used cutoff is ARR >30 (when aldosterone in ng/dL and renin activity in ng/mL/h) 4
The European Society of Cardiology explicitly supports performing ARR testing without stopping current medications, with a preferred approach of testing without medication changes for efficiency, then interpreting results in context of current medications 1, 5
Medications such as beta-blockers, NSAIDs, alpha-2 agonists, and steroids can cause false-positive results, while ACE inhibitors, ARBs, and diuretics can cause false-negative results 1
Correcting hypokalemia before testing is crucial, as low potassium suppresses aldosterone production and causes false-negatives 6
The American Heart Association recommends referring patients with positive ARR results to a hypertension specialist or endocrinologist for confirmatory testing (saline suppression test or oral salt loading) 2, 3

The European Society of Cardiology recommends ordering renal Doppler ultrasound as first-line imaging for renal artery stenosis 1
If Doppler is inconclusive or there is high clinical suspicion, proceed to abdominal CT angiography or MRI 1
The American Heart Association recommends suspecting renal artery stenosis in patients with age <40 years (suggesting fibromuscular dysplasia) or age >60 years with acute change in blood pressure or flash pulmonary edema (suggesting atherosclerotic disease) 1
Medical therapy is the first-line treatment for atherosclerotic renal artery stenosis, with revascularization (angioplasty ± stenting) considered only if medical management fails or for fibromuscular dysplasia 2, 3

The European Society of Cardiology recommends ordering overnight polysomnography for all patients with resistant hypertension, as up to 60% have obstructive sleep apnea (OSA) 1
Clinical clues suggesting OSA include non-dipping or reverse-dipping pattern on 24-hour ambulatory blood pressure monitoring, obesity, and symptoms of snoring, witnessed apneas, excessive daytime sleepiness, and morning headaches 1
The American Academy of Sleep Medicine recommends using the apnea-hypopnea index (AHI) >5 to confirm the diagnosis of OSA, with severity classification as mild (AHI <15), moderate (AHI 15-30), and severe (AHI >30) 1

The European Society of Cardiology recommends excluding pseudo-resistance before declaring true resistant hypertension, by confirming poor adherence, ruling out white-coat hypertension, ensuring proper blood pressure measurement technique, and verifying adequate diuretic therapy 5
The American Heart Association recommends checking plasma creatinine, eGFR, and urinalysis for renal parenchymal disease, and considering 24-hour urinary or plasma metanephrines if paroxysmal symptoms suggest pheochromocytoma 1, 2, 3