1. Definition, classification, and epidemiology
2. Pathophysiology and causes of secondary hypertension
3. Clinical assessment, BP measurement, and target-organ damage
4. Investigations and cardiovascular risk assessment
5. Non-pharmacological and drug treatment
6. Hypertensive urgency and emergency
7. Hypertension in pregnancy and special populations
8. Complications and follow-up

1. Definition, classification, and epidemiology
2. Pathophysiology and causes of secondary hypertension
3. Clinical assessment, BP measurement, and target-organ damage
4. Investigations and cardiovascular risk assessment
5. Non-pharmacological and drug treatment
6. Hypertensive urgency and emergency
7. Hypertension in pregnancy and special populations
8. Complications and follow-up

Hypertension Notes - Medicine 3rd Year

1. Definition

• Usually asymptomatic.
• Major modifiable risk factor for stroke, myocardial infarction, heart failure, chronic kidney disease, atrial fibrillation, peripheral arterial disease, and vascular dementia.
• Most cases are primary (essential) hypertension.
• A minority have an identifiable cause: secondary hypertension.

---

2. Classification of Blood Pressure

A. ACC/AHA classification

B. Traditional / ESC-ESH clinical classification

---

3. Types of Hypertension

A. Primary or essential hypertension

• About 90%-95% of cases.
• No single identifiable cause.
• Multifactorial: genetic predisposition plus environmental influences.

Important contributors

• Family history
• Aging
• Obesity and insulin resistance
• High salt intake
• Low dietary potassium
• Alcohol excess
• Physical inactivity
• Smoking
• Psychosocial stress
• Obstructive sleep apnea
• Chronic kidney disease

B. Secondary hypertension

• Around 5%-10% of patients.
• Has a specific, potentially treatable cause.
• Suspect when hypertension is abrupt, severe, early-onset, resistant, or associated with clues such as hypokalemia, proteinuria, or disproportionate target-organ damage.

---

4. Pathophysiology of Essential Hypertension

A. Increased sympathetic nervous system activity

• Raises heart rate, cardiac output, and peripheral vascular resistance.
• Prominent in stress, obesity, sleep apnea, and early hypertension.

B. Renin-angiotensin-aldosterone system activation

• Renin converts angiotensinogen to angiotensin I.
• ACE converts angiotensin I to angiotensin II.
• Angiotensin II causes vasoconstriction and stimulates aldosterone.
• Aldosterone increases sodium and water retention.

C. Renal sodium retention

• Impaired renal sodium excretion raises extracellular fluid volume.
• This elevates cardiac output initially, followed by increased peripheral resistance.

D. Endothelial dysfunction

• Reduced nitric oxide-mediated vasodilation.
• Increased endothelin and oxidative stress.
• Promotes vasoconstriction and vascular inflammation.

E. Vascular remodeling

• Persistent pressure causes medial hypertrophy and narrowing of arterioles.
• Increases systemic vascular resistance.
• Leads to a self-perpetuating cycle of hypertension.

F. Arterial stiffness

• Especially important in elderly individuals.
• Causes increased systolic BP and widened pulse pressure.
• Leads to isolated systolic hypertension.

---

5. Clinical Features

• Occipital headache, especially early morning
• Dizziness
• Palpitations
• Fatigue
• Blurring of vision
• Epistaxis

Symptoms suggesting target-organ damage

• Chest pain: acute coronary syndrome, aortic dissection
• Dyspnea: left ventricular failure or pulmonary edema
• Neurologic deficit: stroke
• Confusion, headache, seizures, visual disturbance: hypertensive encephalopathy
• Reduced urine output or hematuria: renal injury
• Sudden visual loss: severe hypertensive retinopathy

---

6. Correct Blood Pressure Measurement

Preparation

• No smoking, caffeine, or exercise for at least 30 minutes.
• Empty bladder.
• Quiet environment.
• Patient seated and resting for at least 5 minutes.
• Back supported, feet flat on floor, legs uncrossed.
• Arm supported at heart level.
• Use a validated, calibrated device.
• Correct cuff size:
  • Bladder length: about 75%-100% of arm circumference
  • Bladder width: about 37%-50% of arm circumference

Technique

1. Measure BP in both arms at the first visit.
2. Use the arm with the higher value for later measurements.
3. Take at least two readings, 1-2 minutes apart.
4. Average the readings.
5. Repeat on separate visits unless BP is severely elevated or there is acute target-organ damage.
6. Measure standing BP, especially in elderly people, diabetes, autonomic dysfunction, or symptoms of postural hypotension.

Korotkoff sounds

• Phase I: first tapping sound = systolic BP
• Phase V: disappearance of sounds = diastolic BP

White-coat hypertension

• High clinic BP but normal home/ambulatory BP.
• Increased future risk of sustained hypertension.
• Usually observe, assess cardiovascular risk, and emphasize lifestyle measures.

Masked hypertension

• Normal clinic BP but elevated out-of-office BP.
• Higher cardiovascular risk than normotension.
• Common in diabetes, chronic kidney disease, smokers, and patients with sleep apnea.

---

7. Evaluation of a Patient With Hypertension

A. Objectives

1. Confirm persistent hypertension.
2. Assess total cardiovascular risk.
3. Look for hypertension-mediated organ damage.
4. Identify secondary hypertension.
5. Identify contributing lifestyle factors and medicines.
6. Select appropriate treatment.

B. History

Risk factors

• Family history of hypertension, premature cardiovascular disease, or stroke
• Diabetes, dyslipidemia, chronic kidney disease
• Smoking
• Obesity
• High salt intake
• Alcohol
• Sedentary lifestyle
• Sleep apnea symptoms: snoring, witnessed apneas, daytime sleepiness

Symptoms of target-organ damage

• Angina, dyspnea, orthopnea, paroxysmal nocturnal dyspnea
• Palpitations
• Transient ischemic attack or stroke symptoms
• Headache, seizures, visual symptoms
• Claudication
• Nocturia, edema, reduced urine output

Drug history

• NSAIDs
• Oral contraceptive pills
• Corticosteroids
• Decongestants and sympathomimetics
• Cocaine, amphetamines
• Cyclosporine, tacrolimus
• Erythropoietin
• Herbal drugs, especially liquorice
• Alcohol

C. Examination

General

• BMI and waist circumference
• Pulse rate and rhythm
• Signs of Cushing syndrome or thyroid disease
• Features of acromegaly
• Neurocutaneous signs of neurofibromatosis

BP assessment

• Both arms
• Standing BP for postural drop
• Consider lower-limb BP if coarctation is suspected

Cardiovascular system

• Displaced apex beat, LV heave
• S4 gallop
• Murmurs
• Signs of heart failure
• Peripheral pulses and bruits

Abdomen

• Renal masses
• Abdominal bruit suggesting renal artery stenosis

Fundus examination

1. Arteriolar narrowing
2. Arteriovenous nicking
3. Hemorrhages, cotton-wool spots, hard exudates
4. Papilledema in malignant hypertension

---

8. Investigations

A. Routine investigations

B. Tests for secondary causes, when indicated

---

9. Hypertension-Mediated Organ Damage

Heart

• Left ventricular hypertrophy
• Ischemic heart disease
• Heart failure, initially HFpEF and later HFrEF
• Atrial fibrillation
• Sudden cardiac death

Brain

• TIA
• Ischemic stroke
• Intracerebral hemorrhage
• Vascular cognitive impairment/dementia
• Hypertensive encephalopathy

Kidneys

• Albuminuria/proteinuria
• Hypertensive nephrosclerosis
• Progressive CKD
• End-stage kidney disease

Eyes

• Hypertensive retinopathy
• Retinal hemorrhages/exudates
• Papilledema in malignant hypertension

Blood vessels

• Aortic aneurysm/dissection
• Peripheral arterial disease
• Carotid artery disease

---

10. Secondary Hypertension

When should you suspect it?

• Onset before age 30 years, especially if no family history or obesity
• Abrupt onset or sudden worsening
• Severe hypertension
• Resistant hypertension
• Recurrent hypertensive emergencies
• Unprovoked hypokalemia
• Proteinuria or renal dysfunction
• Abdominal bruit
• Episodic headache, sweating, and palpitations
• Clinical features of endocrine disease
• Disproportionate target-organ damage

Important causes

A. Renal causes

1. Renal parenchymal disease
   • CKD, chronic glomerulonephritis, polycystic kidney disease
   • Most common secondary cause overall
2. Renovascular hypertension
   • Atherosclerotic renal artery stenosis in older patients
   • Fibromuscular dysplasia in young women
   • Clues: abdominal bruit, recurrent flash pulmonary edema, abrupt rise in creatinine after ACE inhibitor/ARB

B. Endocrine causes

1. Primary aldosteronism
   • Resistant HTN, hypokalemia, metabolic alkalosis
   • High aldosterone-renin ratio
2. Pheochromocytoma
   • Episodic headache, sweating, palpitations
   • Paroxysmal or labile hypertension
   • Test metanephrines
3. Cushing syndrome
   • Central obesity, moon face, striae, diabetes, proximal myopathy
4. Thyroid disease
   • Hyperthyroidism: mainly systolic HTN
   • Hypothyroidism: mainly diastolic HTN
5. Acromegaly
   • Enlarged hands/feet, coarse face, glucose intolerance

C. Other causes

• Obstructive sleep apnea
• Coarctation of aorta
• Pregnancy-associated hypertension
• Drugs and substances

---

11. Management of Hypertension

Treatment goals

• <140/90 mmHg for most treated adults
• Often aim for <130/80 mmHg if tolerated in diabetes, CKD, established cardiovascular disease, or high cardiovascular risk
• Avoid excessive lowering in frail elderly patients or those with symptomatic postural hypotension.

---

A. Lifestyle modification

---

B. Drug therapy

First-line drug classes

1. Thiazide or thiazide-like diuretic
   • Chlorthalidone, indapamide, hydrochlorothiazide
   • Useful in elderly persons and salt-sensitive hypertension.
   • Adverse effects: hypokalemia, hyponatremia, hyperuricemia, gout, glucose intolerance.
2. ACE inhibitor
   • Enalapril, lisinopril, ramipril
   • Particularly useful in CKD with albuminuria, diabetes with albuminuria, heart failure, and post-MI LV dysfunction.
   • Adverse effects: dry cough, hyperkalemia, rise in creatinine, rare angioedema.
   • Avoid in pregnancy and bilateral renal artery stenosis.
3. Angiotensin receptor blocker (ARB)
   • Losartan, telmisartan, valsartan
   • Alternative if ACE inhibitor cough occurs.
   • Adverse effects: hyperkalemia and increased creatinine.
   • Avoid in pregnancy and bilateral renal artery stenosis.
4. Calcium-channel blocker
   • Dihydropyridines: amlodipine, nifedipine
   • Good for isolated systolic HTN and elderly patients.
   • Adverse effects: ankle edema, flushing, headache, gingival hyperplasia.

Important rule

---

C. Choosing initial treatment

Stage 1 / mild hypertension

• Lifestyle changes first in lower-risk patients.
• One drug may be suitable if BP is close to target.

Stage 2 hypertension or BP markedly above target

• Start two complementary drugs, preferably as a single-pill combination.

Preferred two-drug combinations

• ACE inhibitor or ARB + CCB
• ACE inhibitor or ARB + thiazide/thiazide-like diuretic

Triple therapy

• ACE inhibitor or ARB + CCB + thiazide-like diuretic

Resistant hypertension

• Three appropriate drugs at adequate doses, including a diuretic, or
• Controlled BP requiring four or more agents.

1. Confirm adherence.
2. Exclude white-coat effect using HBPM/ABPM.
3. Identify high salt intake, alcohol excess, and BP-raising drugs.
4. Check for secondary causes.
5. Add spironolactone if potassium and renal function permit.

---

12. Drug Choice in Common Comorbidities

---

13. Hypertensive Crisis

A. Hypertensive urgency

• Severe BP elevation, usually ≥180/120 mmHg
• No acute target-organ damage
• Often called severe asymptomatic hypertension.

Management

• Do not rapidly lower BP.
• Recheck BP after rest and correct measurement.
• Reinstate/intensify oral medication.
• Assess adherence and precipitating factors.
• Close follow-up within days.

B. Hypertensive emergency

Examples

• Hypertensive encephalopathy
• Intracerebral hemorrhage
• Acute ischemic stroke with special BP indications
• Acute pulmonary edema / acute LV failure
• Acute coronary syndrome
• Aortic dissection
• Acute kidney injury
• Eclampsia
• Malignant hypertension with papilledema

General BP-lowering principle

• Reduce mean arterial pressure by no more than 20%-25% in the first hour.
• Then reduce to approximately 160/100-110 mmHg over the next 2-6 hours.
• Gradually normalize over the next 24-48 hours.

Common IV drugs

---

14. Malignant Hypertension

• Markedly elevated BP
• Advanced bilateral hypertensive retinopathy
• Retinal hemorrhages, exudates, and papilledema
• Often acute renal impairment
• May cause encephalopathy, heart failure, or microangiopathic hemolytic anemia

---

15. Hypertension in Pregnancy

Classification

1. Chronic hypertension
   • Present before pregnancy or diagnosed before 20 weeks gestation.
   • Also includes hypertension that persists beyond 12 weeks postpartum.
2. Gestational hypertension
   • New hypertension after 20 weeks gestation.
   • No proteinuria or features of maternal organ dysfunction.
3. Preeclampsia
   • New hypertension after 20 weeks with proteinuria and/or maternal organ dysfunction.
4. Eclampsia
   • Preeclampsia with seizures.
5. Chronic hypertension with superimposed preeclampsia
   • Worsening hypertension with new proteinuria or maternal organ dysfunction.

Preeclampsia

Diagnosis

• BP ≥140/90 mmHg on two occasions

• Proteinuria, or
• Maternal organ dysfunction, such as thrombocytopenia, renal impairment, elevated liver enzymes, pulmonary edema, persistent neurologic symptoms, or visual disturbance.

Severe features

• BP ≥160/110 mmHg
• Severe headache, visual symptoms
• Epigastric/right upper quadrant pain
• Pulmonary edema
• Thrombocytopenia
• Elevated liver enzymes
• Renal impairment
• Fetal growth restriction

Drugs safe in pregnancy

• Labetalol
• Nifedipine
• Methyldopa
• Hydralazine, especially IV in severe hypertension

Contraindicated in pregnancy

• ACE inhibitors
• ARBs
• Direct renin inhibitors

Eclampsia treatment

• Stabilize airway, breathing, circulation.
• Magnesium sulfate for seizure prevention/treatment.
• Control severe BP.
• Definitive treatment is delivery after maternal stabilization, depending on gestation and maternal-fetal status.

---

16. Short Exam Answers

Define resistant hypertension.

What is white-coat hypertension?

What is masked hypertension?

What is isolated systolic hypertension?

What is hypertensive emergency?

What are the main first-line drugs?

• Thiazide/thiazide-like diuretic
• ACE inhibitor
• ARB
• Calcium-channel blocker

---

17. One-Minute Revision

• Confirm hypertension with repeated readings and preferably HBPM/ABPM.
• Essential HTN is the commonest type.
• Suspect secondary HTN in young onset, abrupt worsening, resistant HTN, hypokalemia, renal disease, or episodic symptoms.
• Assess heart, brain, kidneys, retina, and vessels for target-organ damage.
• Lifestyle therapy is for all patients.
• First-line drugs: thiazide-like diuretic, ACEi, ARB, CCB.
• Preferred combination: ACEi/ARB + CCB or thiazide-like diuretic.
• Do not combine ACEi + ARB.
• Hypertensive emergency means severe BP plus acute target-organ damage.
• In emergency, lower MAP by no more than 20%-25% in the first hour, except condition-specific situations such as aortic dissection.
• Pregnancy-safe drugs: labetalol, nifedipine, methyldopa. Avoid ACEi and ARBs.