Hypertension

Essential Hypertension:

Definitions:

• HTN: ≥ 140\90
• Isolated systolic HTN: SBP >140 and DBP <90
• Isolated diastolic HTN: SBP <140 and DBP > 90
• White coat HTN: office readings > 140\90 but out of office readings < 140\90
• Definition of HTN based on home\ambulatory reading:
  • 24 hr average: > 135\85
  • Day time average: > 140\90
  • Night time average: > 125\75

Classification:

» If systolic and diastolic are in different stages -> use the higher stage

• Normal: < 120\80
• Pre-hypertensive: 120-139 \ 80-89
• Stage 1 HTN: 140-159 \ 90-99
• Stage 2 HTN: ≥160\100

Pathophysiology:

• Genetic + environmental

Diagnosis:

• 2 or more readings on 2 separate clinic visits
• Lab investigations: Cr, GFR, Na, K, fasting glucose, hematocrit (polycythemia -> polycystic kidney ds), UA, lipids, ECG

 

When to start anti-hypertensive medication?

1. Younger than 60 yr: SBP > 140
2. Older than 60 yr: SBP > 150

• Initial monotherapy: thiazide, long acting Ca channel blocker, ACEI\ARBs
• If inadequate response -> increase dose OR add another
• 2 drugs -> stage 2 HTN

Indications:
CKD, DM	ACEI\ARBs
CHF	ACEI\ARBs, diuretics, aldosterone antagonist
MI	B-blockers, ACEI, aldosterone antagonist
BPH	a-adrenergic blockers
Angina, migraine, essential tremor	B-blockers

Contraindications:
Pregnancy	ACEI\ARBs
Asthma, COPD, PAD	B-blockers
Gout	Diuretics
Heart block	B-blockers, verapamil, diltiazem

 

Anti-hypertensive agents:

 

---

Secondary Hypertension:

Clues:

• Age of onset < 30 or > 50
• BP > 180\110 at dx
• Resistant HTN to 3 or more drugs including diuretics

Causes:

• Renal A stenosis: check table!
• Pheochromocytoma: check table!
• Hyperaldosteronism: check table!
• Hypercortisolism: check table!
• OSA
• Hypo\hyper thyroid, hypercalcemia
• Polycythemia
• Drugs: OCP, steroids, NSAIDs, EPO, cyclosporine, licorice
• Coarctation of aorta:
  • In children \ adulthood
  • HTN in upper extremities, no\delayed femoral pulses, low\no BP in lower extremities
  • Machinery murmur over post chest
  • CXR: rib notching + “3 sign”

 

 

---

Hypertensive Crisis:

Definitions:

• Hypertensive urgency: severe HTN w\out acute target organ damage
• Hypertensive emergency: severe HTN w\ acute end organ damage
• Malignant HTN: check table for clinical features!
• Accelerated HTN: same as malignant HTN but w\out papilledema

Treatment:

• HTN urgency -> ↓ BP w\ oral agents (no need for hospitalizations)
• HTN emergency -> hospitalize + ↓ BP w\ parenteral therapy (↓MAP by 25% in mins-2hrs)

 

---

Resistant Hypertension:  

• Uncontrolled BP despite: 3 or more including diuretics OR 4 or more meds
• Mainly due to secondary causes of HTN

Treatment:

• For persistent volume expansion -> chlorthalidone (preferred to hydrochlorothiazide)
• If GFR < 30 -> loop diuretics
• Aldosterone antagonists
• If still uncontrolled -> labetalol, clonidine, hydralazine, minoxidil

 

---

Hypertension in Pregnancy:

• Chronic HTN: HTN dx before pregnancy or before 20^th week
• Gestational HTN: HTN developing after 20^th week
• Preeclampsia: gestational HTN + proteinuria
• Eclampsia: preeclampsia + seizures

Treatment:

• When to start?
  • SBP > 150 in 2^nd trimester
  • DBP > 100 in 2^nd trimester
  • SBP > 160 in 3^rd trimester
• First line? Methyldopa
• For hypertensive crisis? Labetalol, IV hydralazine, oral nifedipine (avoid nitroprusside)
• For eclampsia \ preventing recurrent seizures? Magnesium sulfate
• What are the indications of delivery?
  • After 34^th week: preeclampsia
  • Before 34^th week: worsening maternal symptoms, end organ damage, deterioration of fetus

 

---

Random notes:

• MCC of death among HTN pt -> CAD
• HTN is the second MCC of ESRD (1^st is DM)

 

---

 Download the PDF version: here

---

References:

• The Johns Hopkins Internal Medicine Board Review
• Dr Alrasheed’s lecture