Submodule
Confirming True Resistant Hypertension
Resistance is a verified phenotype. Apparent resistance may still reflect inaccurate measurement, white-coat effect, incomplete exposure, inadequate doses, or a noncomplementary regimen.
- Apparent versus true resistance
- Controlled resistance
- Outside-office confirmation
- Optimized complementary regimen
Exclude technique and white-coat effect
Confirm complementary therapy and exposure
Find solvable causes before adding treatment
Use maximally tolerated complementary classes
Use the definition precisely
True resistant hypertension includes pressure above goal despite three complementary agents at maximum or maximally tolerated doses, commonly a long-acting dihydropyridine calcium-channel blocker, an ACE inhibitor or ARB, and a diuretic. Pressure controlled with at least four agents also represents a resistant phenotype.
Keep apparent resistance separate
When dose, adherence, or out-of-office pressure is missing, the correct term is apparent treatment-resistant hypertension. This distinction protects the patient from escalation before white-coat effect, nonuse, and inadequate treatment have been excluded.
Confirm usual pressure exposure
Use standardized office measurement plus validated home monitoring or ambulatory monitoring. Out-of-office data separate sustained uncontrolled pressure from a treated white-coat effect and can identify masked uncontrolled hypertension.
Verify the actual regimen
List each active ingredient, formulation, dose, schedule, duration, missed exposure, adverse effect, and refill barrier. Three medicines do not establish resistance when they duplicate a pathway, use inadequate doses, or lack an effective diuretic.
Quick check
Submodule
Contributors, Interference, and Pseudoresistance
A difficult pressure often reflects several interacting causes: sodium and volume, medicines that raise pressure, access, regimen burden, pain, sleep, alcohol, substances, or inconsistent exposure.
- Medication exposure
- Interfering medicines and substances
- Sodium and volume
- Access and regimen design
Verify long-acting CCB, RAAS blocker, and diuretic
Ask without blame
Include supplements, alcohol, and sodium
Simplify and support before intensifying
Assess exposure without blame
Use open questions, refill history, pill and bottle review, adverse-effect history, and selected biochemical testing when justified. A presence assay can show recent exposure but cannot prove regular therapeutic use over time.
Find medicines that oppose control
Review NSAIDs, decongestants, prescription stimulants, selected hormonal therapies, calcineurin inhibitors, erythropoiesis-stimulating agents, glucocorticoids, some oncology therapies, supplements, nicotine, alcohol, and other substances. The timing of exposure and pressure change matters.
Assess sodium and volume biology
Excess dietary sodium, kidney dysfunction, NSAID exposure, inadequate diuretic delivery, and aldosterone activity can expand volume and blunt other medicines. Use diet, weight, edema, orthostasis, kidney function, electrolytes, and diuretic response together.
Repair the treatment system
Simplify schedules, use appropriate single-pill combinations, synchronize refills, reduce cost, address language and literacy, and change intolerable therapy. Adding drugs to an inaccessible regimen usually adds harm rather than control.
Quick check
Submodule
Secondary Hypertension Screening Architecture
Secondary hypertension workup starts with the phenotype. Age of onset, tempo, potassium, kidney and urine data, sleep pattern, medicines, physical examination, and episodic symptoms determine the useful tests.
- Pretest probability
- Common causes
- Abrupt and severe phenotypes
- Actionable testing
Use renal, electrolyte, and renin-aldosterone data
Snoring, witnessed apnea, sleepiness, obesity
Abrupt change, flash edema, asymmetric disease
Test only when the phenotype supports it
Build the phenotype first
Record age at onset, abrupt worsening, family history, pressure pattern, potassium, kidney function, urinalysis, albuminuria, pulse, body habitus, sleep symptoms, medication exposures, endocrine features, vascular examination, and target-organ injury.
Prioritize common and treatable causes
Primary aldosteronism, kidney parenchymal disease, obstructive sleep apnea, renovascular disease, and drug or substance effects account for much of the actionable work. Less common endocrine and structural causes require stronger clues.
Match the test to the clue
An aldosterone-renin screen, sleep study, kidney evaluation, vascular imaging, thyroid testing, metanephrine testing, cortisol testing, or aortic imaging each has distinct preparation, false-positive risks, and downstream decisions.
Avoid indiscriminate panels
Low-pretest-probability testing produces incidental and borderline results that can lead to repeated imaging or procedures. A focused workup is broader when onset is young, pressure is abrupt or severe, or true resistance and organ damage are present.
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Submodule
Primary Aldosteronism
Primary aldosteronism is an underdiagnosed spectrum of autonomous aldosterone production with suppressed renin, sodium retention, cardiovascular risk, and sometimes hypokalemia.
- Aldosterone and renin screening
- Potassium and medication effects
- Subtype evaluation
- Surgery versus MRA therapy
Measure potassium for interpretation
Posture, time, sodium, and laboratory method matter
Use expert confirmation and subtype evaluation
Match therapy to subtype and candidacy
Screen with aldosterone and renin
The 2025 Endocrine Society guideline conditionally suggests screening all individuals with hypertension when resources and capacity support it. Screening measures aldosterone and renin and calculates their ratio. Potassium is measured to support interpretation, not as the screening test itself.
Prepare and interpret the sample
Low potassium can suppress aldosterone and should be corrected when possible. Sodium intake, posture, time, kidney function, assay method, and medicines that alter renin or aldosterone affect the result. Follow a local protocol rather than using an isolated ratio without context.
Confirm and determine subtype
The need for suppression testing depends on the screening pattern and clinical setting. Patients pursuing surgery generally need expert subtype evaluation. Cross-sectional imaging identifies anatomy, but adrenal venous sampling is often required because incidental nodules do not establish laterality.
Treat the aldosterone source
Unilateral disease may be treated with adrenalectomy in a suitable surgical candidate. Bilateral disease or nonsurgical care uses a mineralocorticoid receptor antagonist. Monitor pressure, potassium, kidney function, and product-specific adverse effects.
Quick check
Submodule
Renal, Sleep, Endocrine, and Structural Causes
Kidney disease, renovascular disease, sleep apnea, thyroid disease, cortisol excess, catecholamine-secreting tumors, and vascular anatomy produce different patterns and require different tests.
- Renal parenchymal and renovascular disease
- Obstructive sleep apnea
- Endocrine testing
- Coarctation and rare causes
Urine, kidney function, imaging when indicated
Sleep testing follows a compatible phenotype
Use syndrome-specific biochemical preparation
Examination and age of onset guide testing
Separate parenchymal from renovascular disease
Kidney function, urinalysis, albuminuria, structural history, and volume help define renal parenchymal disease. Abrupt worsening, flash pulmonary edema, asymmetric kidney findings, diffuse vascular disease, or a marked creatinine response to RAAS blockade can support renovascular imaging when the result would change care.
Recognize obstructive sleep apnea
Snoring, witnessed apnea, sleepiness, resistant pressure, obesity, and compatible anatomy support sleep evaluation. A screening score estimates probability but does not establish the diagnosis. Treatment addresses sleep, symptoms, safety, and cardiovascular risk alongside blood pressure therapy.
Prepare endocrine testing correctly
Thyroid testing follows thyroid clues. Metanephrine testing requires attention to posture, stress, medicines, and acute illness. Cortisol testing uses accepted circadian or suppression strategies rather than a random cortisol. Exogenous glucocorticoids must be identified before an endogenous workup.
Use examination to find structural disease
Young onset, upper-lower extremity pressure differences, delayed femoral pulses, or a murmur can suggest coarctation. Other rare causes follow their own phenotypes. The physical examination remains a high-value localization tool.
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Submodule
Stepwise Resistant Hypertension Treatment
Treatment begins by optimizing the complementary three-drug base, sodium and volume management, and exposure. Mineralocorticoid receptor blockade is a common fourth step, while additional drugs and devices require careful selection.
- Optimized three-drug base
- Mineralocorticoid receptor antagonist
- Later add-on therapy
- Specialist and renal denervation evaluation
Use maximally tolerated doses
Monitor potassium, kidney function, and pregnancy
Match heart rate, volume, kidney, and comorbidity
Renal denervation requires team evaluation and shared decisions
Optimize the foundation
Use maximally tolerated complementary therapy, commonly a long-acting dihydropyridine calcium-channel blocker, an ACE inhibitor or ARB, and an effective diuretic. Long-acting thiazide-like therapy may strengthen the base when kidney function and safety permit.
Target aldosterone biology
Spironolactone is a common fourth-line option when potassium, kidney function, pregnancy status, and interactions permit. Eplerenone may fit selected patients. Early and repeated potassium and kidney monitoring is part of the treatment, not an optional follow-up.
Individualize later therapy
Additional treatment may include agents selected by heart rate, sympathetic activity, volume, kidney function, heart failure, coronary disease, tolerability, and access. Aprocitentan provides a newer endothelin pathway but carries embryo-fetal toxicity and fluid-retention risks and does not replace standard optimization.
Use specialists and devices deliberately
Persistent uncontrolled pressure warrants hypertension-specialist evaluation. Renal denervation is an adjunctive option for selected patients after multidisciplinary confirmation, secondary-cause evaluation, anatomy review, and shared discussion of expected benefit, uncertainty, procedural risk, medicines, and continued follow-up.
Quick check
Module test
Check the connections.
Each attempt draws 10 questions from the complete 100 question bank.
Each attempt draws a fresh set and rearranges the answer choices.
References
Current clinical foundation.
Lecture material was synthesized with the following contemporary guidance. Verify local policy and current guidance before applying clinical information.