TREATMENT OF SYSTEMIC ARTERIAL HYPERTENSION

                              

TREATMENT OF SYSTEMIC ARTERIAL HYPERTENSION

.               TREATMENT OF SYSTEMIC ARTERIAL HYPERTENSION

Essential Assessments:

1. Establish the presence of hypertension

2. Assess the severity and prognosis to select proper therapy

3. Search for presence of secondary hypertension if indicated.

Three important measures in treatment

1. Life style modification and general measures

2. Drug therapy

3. Treatment of secondary hypertension

           

  Life style modification and general measures

 Exercise:

Regular dynamic physical exercise:

brisk walking/ swimming/ cycling -30 -45 min 5dys a wk

Salt restriction 2-4gms /day

DASH diet

(Dietary Approach to Stop Hypertension)

Dash diet –rich in fruits, vegetables, whole grains and low fat dairy foods

Fruits and vegetables: Adequate intake; maintain   adequate K, Ca and Magnesium.low salt

Avoidance /control/treatment of risk factors –

-smoking  - alcohol, obesity, cholesterol and saturated fat.

Recent advances          New reports highlight the risk of hypertension with regular drinking

Alcohol is most controllable and preventable risk factor for hypertension

General measures

a. Patient education

b. Reassurance

 c. Adequate sleep  d.relaxation (meditation and yoga)

Follow up after non pharmacological therapy

.Who should be treated with pharmaco therapy?   JNC 8guidline

Patients;<;60 years of age: start pharmacotherapy at140/90 mmHg.

Patients with diabetes: start pharmacotherapy at140/90 mmHg.

Patients with CKD:  start pharmacotherapy at140/90 mmHg.

 Patients 60 years of age and older: start pharmacotherapy at150/90 mmHg

Standard target  BP –less than 140mm systolic in overall population group

  Lower targets previously recommended in diabetes, CKD, and CAD are of unproven benefit.

  Use clinical judgement and consider risk/benefit ratio

   In addition continue lifestyle changes

Thus similar treatment goals have been defined for all hypertensive population and no distinction between uncomplicated hypertension and hypertension with comorbid conditions like diabetes or chronic kidney disease (CKD) has been made

Essentials of JNC 8 recommendations 2013

1. Less aggressive targeting of blood pressures No BP goals<140 font="">

2. BP goal for patients 65+ year old, < 150/90 mm Hg

3. In patients between 18-60 yrs old with DM or CKD initiation goals140/90

In these patients-ACEI or ARB is used

(initial or add on drug)

4. Thiazide-type diuretics no longer indicated as the initial therapy in most patients

1st Line therapy can be: ACEI or ARB or CCB or Thiazide type diuretic

5. Home BP or ambulatory BP encouraged

Treatment Plan -JNC8

For all hypertensive population similar treatment goals have been defined

No distinction between uncomplicated hypertension and hypertension with comorbid conditions like DM or  CKD.

De-emphasis on choice of agent for compelling indications;

focus is on  BP control using four medication

Choice of drugs

All 4drug classes beneficial

1st Line therapy can be:

 ACEI or ARB

 or CCB or

 Thiazide type diuretic-Chlorthalidone is thiazide of choice

NOTE:Thiazide-type diuretics no longer indicated as the initial therapy in most patients

             Chlorthalidone favoured over hydrochlor thiazide

 Precautions

              1.β-blocker not a 1st line choice for HTN: Vaso-dilating β-blockers- drugs of choice

            2.Calcium channel blockers    “Short acting CCBs not recommended”

·         3.ACEI and ARB should not be combined no added benefit, more side effects (e.g., hyperkalemia)not to combine K sparing diuretics

  Treatment regime

Initial Mono therapy in Hypertension:

3 groups of drugs useful;

1 thiazide diuretics

2.Long acting calcium channel blockers

3.ACE inhibitors/ARB

B blockers  not indicated for initial monotherapy (high risk of CVS complications)except when there are specific indications like angina,rate control

2drug regime is required in most patients especially if systolic is >20mm above goal or diastolic>10 mm above goal    

·         Choose once-daily or combination products to simplify the regimen

·         In general, if goal in not reached wait two to three weeks before increasing dose or adding new drug.

·         continue to assess BP and adjust treatment regime until goal BP is reached

·         If 2 drugs are not adequate,3^rd drug from the above list added and dose titrated

3 drug regimen-ACEI/ARB+CCB+diuretics beneficial

·         ACI and ARB should not be combined;βblockers and diuretics are not to be combined

·         if goal BP is not reached with only above 4 drugs recommended,drugs from other classes can be used

·         If not successful-refer to hypertension specialist

·         Note:for HTN, beta- and alpha-blockers have  bad CV outcomes data

·         Thiazides and CCBs reduce systolic BP more than diastolic BP

Isolated Systolic hypertension: 

·          this is most common form of uncontrolled hypertension

·         It is important risk factor for vascular complications

Diastolic Hypertension:may be clinical marker of hypertensive emergencies and urgencies

Hypertension in elderly patients must be treated to avoid complications

Other anti hypertensives;  (apart from first line drugs )

A variety of vasodilators are available

1. Alpha -blockers (selective alpha₁adrenoceptor antagonists)

2. Drugs acting directly on vascular smooth muscles

3Centrally acting drugs

4and loop diueretics,aldosterone diuretics

These other antihypertensives use is eliminated in JNC8 guideline

But take caution in patients who are already stabilized with these

SPECIAL SITUATIONS

Diabetes:

In type 2 diabetes – 20% have hypertension

In type 1 diabetes  - 30-50% have hypertension

ACE inhibitors are first line drugs in these patients with or without microalbuminuria and/ nephropathy.

ACE inhibitors reduce microalbuminuria.

Renin angiotensin system blockade retards decline in renal function by mechanism other than reducing BP.

 

. Specific  therapy recommendation provided for  African Americans

         Nonblack, including those with diabetes:

         Thiazide, CCB, as1st line & ACEI, or ARB as add on drugs

HYPERTENSIVE CRISIS

Hypertensive crisis is defined as BP more than 180/110 mm of Hg.

Hypertensive crisis consists of

I. Hypertensive emergencies

     II Hypertensive urgencies

HYPERTENSIVE EMERGENCY:

This is severe hypertension with acute impairment of end organ

              (E.g. Brain, heart, kidney and eyes)

Includes accelerated hypertension and malignant hypertension

(By definition Systolic BP above 180 systolic and 110 diastolic)

In these conditions, the BP should be lowered aggressively but carefully

 to prevent death or severe end organ damage

HYPERTENSIVE URGENCY

In this the BP is a potential risk but has not yet caused acute end-organ damage,

Urgency is defined as severely elevated BP (e.g. systolic above 220mm of Hg or diastolic above 120mm of Hg) with no evidence of  target organ damage.

Initial goal in treatment is to attain a diastolic BP of 100-110 mmHg within several hours.

Normal BP can be attained over several days gradually with oral drugs

Precipitous fall in BP is to be avoided to prevent cerebral ischemia or coronary insufficiency.

Level of Hypertension and vascular damage

A persistent diastolic BP above 120mm of Hg is often associated with acute vascular damage: Some patients suffer vascular damage from lower levels of BP; others withstand high levels without harm.

So rapidity of rise is more important than absolute levels.

In practice DBP above 120mm of Hg must be treated –some rapidly with parenteral drugs some slowly with oral drugs

HYPERTENSIVE CRISIS :Flow chart

Principles of treatment in crisis
 Urgency:
          Outpatient
          Oral medication
          BP reduction in 24 -48 hrs
Emergency
           Inpatient
           Intravenous
           Immediate BP reduction less than 25% within minutes to 1 hour.
           160/100 in 2-6 hrs

Intravenous antihypertensives
Nitroglycerine
Sodium nitroprusside
Enalaprilat (only ACE inhibitor in Intravenous form)
Nicardipine
Clevidepine
Esmelol
Labetalol
Oral drug for Hypertensive urgency
Amlodipine 5-10mg  12th hrly
Captopril      12.5-25mg 6th hrly
Nicardipine   20-30mg 6-8 hrly       
Labetalol       200-400 mg 8-12 hrly

Lasix                 20-40mg  8-12 hrly


Conditions in which severe hypertension occurs

1.      Essential hypertension( Asymptomatic uncontrolled hypertension)

2.      Renal disorders

3.      Pregnancy

4.      Drugs

5.      Substance abuse: Acute cocain,amphetamine poisoning(acute sympathetic crisis)

6.      Acute post operative hypertension(Often BP is 220/130)

Target organ damages that may occur in hypertensive emergencies

 Acute coronary syndrome

Pulmonary edema

Acute Aortic dissection

Acute Cerebral infarction, intracerebral /subarachnoid hemorrhage

Hypertensive encephalopathy

Eclampsia

Acute renal failure,

                                  

Severe hypertension was formally called as malignant hypertension

Hypertensive crisis is associated with excess circulating catecholamines

 it is acute BP elevation.

Note: Definition of emergency and urgency do not specify absolute BP levels

Both may occur in a normotensive with a modest increase in BP as in

             Eclampsia or acute cocaine or amphetamine intoxication.

     Sub lingual nifedapine therapy is now obsolete because

   ischemic complications can occur from   sudden fall of BP.

Genetics in hypertension treatment

 New research shows genetic variants play a role in determining CVD outcomes. In hypertension

two variants in a gene called NPPA-that encodes for (ANP)atrial natriuretric plypeptide discoveredThis can lead to methods to regulate ANP and so prevent or control hypertension

NEW DEVELOPMENTS IN PHARMACOLOGICAL TREATMENT OF HYPERTENSION

There are broad ranges of new possible therapeutic targets for hypertension described belo

Number of new molecules described below are being investigated

Vaso peptidase inhibitors:

1.Dual ACE/NEP inhibitor.

2.dual angiotensinreceptor(AT1)/NEP inhibitor

3.Dual NEP/endothelin inhibitionand  angiotensin receptor(AT1)/endothelin blockade

Phospho diesterase inhibition

Vaso active intestinal peptide agonist

Natriuretic peptide receptor A agonist

Protective RAAS

Angiotensin A2 receptor agonist

ACE2/Ang(1-7)Mas receptor Axis agonist

SYSTEMIC ARTERIAL HYPERTENSION-ABSTRACT

Definition –BP greater than 140/90 and  persistent

Usually diagnosed during  a routine check up in asymptomatic person

Integral part of evaluation is proper technique of BP measurement

Ambulatory BP measurement is gaining impotance

Certain criteria (conditions) are set for recording of BP

Etiology –Idiopathic or Secondary95% is essential hypertension

Treatment is important to avoid morbidity and mortality of complications

Since majority of patients are asymptomatic, careful early evaluation is needed

Malignant hypertension is high BP associated with target organ damage

First step in treatment of hypertension is  life style modifications

Amongst  several classes of  antihypertensives are available-JNC8 recommends

1.ACE inhibitors or ARB

3.Diuretics

4.Calcium Channel Blockers

Start with a low dose and then increase

Regular monitoring of blood pressure is essential.

Hypertensive crisis consists of Hypertensive emergency and urgency

Hypertensive emergency is high BP associated with acute target organ damage

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