Resistant Hypertension (RHTN) is defined as uncontrolled blood pressure despite the use of ≥3 antihypertensive agents of different classes, including a diuretic, usually thiazide-like, a long-acting calcium channel blocker, and a blocker of the renin-angiotensin system, either an ACE (angiotensin-converting enzyme) inhibitor or an ARB (angiotensin receptor blocker), at maximal or maximally tolerated doses.
Secondary causes of Resistant Hypertension include Obstructive Sleep Apnea, Renal Artery Stenosis, Renal Parenchymal Disease, and Primary Aldosteronism, along with some uncommon Resistant Hypertension causes such as Pheochromocytoma, Cushing's disease, thyroid, a...
