Hypertension

HTN
Primary
or Essenstial 
Idioppathic
Most common type accordung for 90-95% of the cause 
Secondary HTN
Due to Identifed Cause 
Eg: Primary  aldosreronisn chronic kidney disease renovascular disease oral contraceptive pills etc.

Definitions:
Hypertension is defined as sustained increase in resting systolic BP (≥ 140 mmHg), diastolic BP (≥90 mmHg), or both, when not on anti-hypertensive medications and not in acute illness.

 

Epidemiology:

  • Accounts for~75 million deaths annually (12.8% of all deaths) (WHO).

  • It is considered the leading risk factor for silent death in KSA.

  • Hypertension is present in more than 25% of general population. 60% of those with HTN are on treatment and only half are adequately controlled.

  • It is the most important modifiable risk factor for coronary heart disease and vascular diseases, stroke, and end stage renal disease.

Types:

Study guide:

Etiology:

  • Essential Hypertension (Multifactorial): 

    • Environmental factors: Stress, sodium intake, obesity, and smoking.

    • Genetics: 10 Genes, found mutated, were responsible for B.P regulation through Na/H2O reabsorption by the kidneys.

  • Secondary Hypertension:

    • Reno-Vascular Disease (most common cause).

    • Renal parenchymal disease.  

    • Hypercortisolism.

    • Pheochromocytoma.

    • Cortication of the aorta.

    • Hyperthyroidism.  

    • Medications: OCP, steroids, NSAIDS, EPO, cyclosporine, licorice.  

Risk factors:

Pathophysiology:

  • Physiology: BP = Cardiac output (CO) x Total peripheral resistance (TPR)

  • BP is product of cardiac out put (CO) and total peripheral vascular resistance (TPR), most of patient with long standing HTN have increase TPR with normal or diminish CO.

  • Hypertension is the end result of ↑ C.O, ↑TPR, or ↑in both of them.

    • Increase vascular stiffness contribute to systolic HTN in the elderly (thus isolated systolic hypertension is more common among elderlies).

 

Clinical presentation:

  • Usually Asymptomatic, until end organ damage develop (Silent Killer!).

  • White coat Hypertension: Patient has hypertensive BP when measured in the clinic, normal outside, usually attributed to anxiety.

  • Some times, initial presentation will be hypertensive crisis:

    • Hypertensive Emergency: Severe Hypertension (diastolic >120mmHg) in patients with acute ongoing end organ failure.

    • Hypertensive Urgency: Severe Hypertension (diastolic >120mmHg) in asymptomatic patients with no end organ failure.

  • Signs and symptoms (indicating complicated Hypertension):

    • Dizziness

    • Headache

    • Epistaxis

    • Flushed face

    • Fatigue

    • Nervousness

Diagnosis:

Table 1: Blood Pressure Classification adopted from JNC 7 Guideline & Step up to Medicine 3rd Edition, created by LtMed. 

  • Hypertension is diagnosed using a Sphygmomanometer.

  • History, physical Examination and other tests ordered are to check if any underlying etiology and/or any organ damage are present.

  • Methods of measuring B.P:

    1. Ambulatory blood pressure monitoring (ABPM):

      • Indications:

        • Suspected white coat HTN.

        • Suspected episodic HTN.

        • Resistant HTN (BP >140/90mmH Despite using 3 or more drug classes, one of which is Thiazide diuretic).

        • Hypotensive symptoms while taking anti hypertension medication.

    2. Home Blood Pressure monitoring: (3A4 measures a day).

    3. Office-Based Blood Pressure Measurements:  

      • Still the primary method for diagnosis and management of hypertension.

      • BP measured twice; patient seated and standing, separated by≥ 2min.

      • Measured on 3 separate visits, each separated by at least 1 week.

      • Preferably, measure both arms; ideally, the blood pressure difference should be no more than 15 mmHg.

      • "  If systolic and diastolic BP are in different stages the higher stage is used. 

Screening:

  • According to USPSTF, all adults should check their BP:

    • If normal BP → recheck every 2 years.

    • If preAHypertensive → recheck every year.   

Management:

  1. Non-Pharmacological Treatment (life style modifications, LSM):

    • ↓Weight to reach the normal BMI.

    • Follow DASH diet (high vegetables/fruits, low fat/ sweets and red meat).

    • Restrict Sodium intake (<2.4g/day).

    • Physical activity (Aerobic exercises for 30 min/day at least 4 days a week= 180min per week).

    • Limit alcohol consumption (two standard drinks for males and one for females).

    • Smoking cessation.   

  2. Pharmacological Treatment:

    • Should be initiated when blood pressure is 150/90 mm Hg or higher in adults 60 years and older, or 140/90 mm Hg or higher in adults younger than 60 years.

    • In patients with DM, it should be initiated when blood pressure is 140/90 mm Hg or higher, regardless of age.

    • If the target blood pressure is not reached within one month after initiating therapy -> increase the dose or add a second medication.

    • Drug Classes Used in treatment of Hypertension:

      • Thiazides

      • Ca+ Channel Blockers (along with thiazide, the best initial therapy for black patients).

      • Angiotensin converting enzyme inhibitors (ACEI) and angiotensin receptor blocker (ARB) -> best initial therapy for patients with DM or CKD.

      • Others: beta-blockers and aldosterone antagonists -> if other medications failed.

  3. Management of Hypertensive Crises:

    • Hypertensive urgency:

      • Oral hypertensive drugs (beta blockers, clonidine, ACEIs).

      • Lower the BP gradually over 24A48 hours.

    • Hypertensive emergency:

      • IV hypertensive drugs (labetalol, nitroprusside, nicardipine).

      • Lower the mean arterial pressure by 25% over the first 2 hours to prevent cerebral hypoperfusion or coronary insufficiency.

Blood pressure target: according to JNC8 recommendations:

  • All patients at any age with CKD, DM or both -> BP<140/90mmHg.

  • Patients < 60years of age with no CKD nor DM -> BP<140/90mmHg.

  • Patients > 60 years of age with CKD nor DM -> BP<150/90mmHg.  

Golden rules:

  • White and < 65 -> ACEI or ARB.

  • Black > 65 -> Ca channel blockers or thiazides, you can also add beta blockers if not contraindicated.

Complications:

  • Stroke (HTN is the most common risk factor for strokes)

  • Coronary artery Disease (Most common cause of death)

  • Left ventricular Hypertrophy 

  • Congestive Heart Failure

  • Peripheral Artery Disease

  • Retinopathy

  • Aortic Dissection

  • Renal failure

Follow up:

  • Assess adequacy of disease management.

  • Assess overall cardiovascular disease risk.

  • Assess the extent of endAorgan damage.

  • Cardiopulmonary exam.

  • Optic fundi.  

  • Abdominal exam (aneurysm, bruits, organomegaly).

  • Neurologic exam.

  • Rule out secondary causes of HTN.

  • Check K and creatinine twice a year.  

References:

First author:       Husam Tahan 


​Second author:  Lama Al Luhidan 

Reviewed by:     Roaa Amer 
                          Lujain AlKhalifa

Web Publisher:   Bayan Alzomaili

​Audio recording:


Read by: Assil Berkeit
 

Directed by: Jinan Ramzi AlRashoud
 

Audio production: Bayan Alzomaili

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