Hypertension

What is Blood Pressure? – Pressure created by the heart as it pumps blood through the arteries and the circulatory system What do Blood Pressure Numbers Mean? – Top number (Systolic)= Pressure while heart is beating – Bottom number (Diastolic)= Pressure while heart is resting between beats Lifestyles, fitness and rehabilitation

Hypertension Normal Blood Pressure – Blood Pressure of < 140/ 90 – Blood Pressure of 130 to 139/ 85 to 89 should be closely watched High Blood Pressure – Blood Pressure > 140/ 90 Lifestyles, Fitness and Rehabilitation

Hypertension How can I tell if I have High Blood Pressure? – Usually NO SYMPTOMS! – “The Silent Killer” – May have: Headache Blurry vision Chest Pain Frequent urination at night Lifestyles, Fitness and Rehabilitation

Hypertension Blood Pressure Measurement – Sphygmomanometer – Systolic pressure= pressure when 1st sound is heard – “Diastolic pressure= pressure when last sound is heard Blood Pressure Cuff Size – Small – children and small adults – Average – Large – overweight and large adults

American Heart Association Recommended Blood Pressure Levels BP Category Systolic (mmHg) Diastolic (mmHg) Follow-up Optimal < 120and < 80Recheck 2 years Normal < 130and < 85Recheck 2 years High Normal or 85-89Recheck 1 year

American Heart Association Recommended Blood Pressure Levels BP Category Systolic (mmHg) Diastolic (mmHg) Follow-up Stage 1 (mild HTN) or Confirm within months Stage 2 (moderate HTN) or Evaluate within 1 month Stage 3 (severe HTN) 180 or > or 110 or > Evaluate immediately

Hypertension What Causes High Blood Pressure? – Cause unknown in 90 to 95% of cases = Primary Hypertension – Secondary Hypertension = 5 to 10% Kidney Abnormalities Narrowing of certain arteries Rare tumors Adrenal gland abnormalities Pregnancy

Hypertension What Causes High Blood Pressure? – Controllable Risk Factors Increased salt intake Obesity Alcohol Stress Lack of exercise

Hypertension What Causes High Blood Pressure? – Uncontrollable Risk Factors Heredity Age – Men between age 35 and 50 – Women after menopause Race – 1 out of every 3 African Americans – Higher incidence in non-Hispanic blacks and Mexican Americans

Hypertension Women and High Blood Pressure – Birth Control Pill – Pregnancy – Overweight – After Menopause – African Americans

Hypertension What does High Blood Pressure do to my Body? – Stroke – Congestive heart failure – Kidney failure – Heart attack – Heart rhythm problems – Aneurysm

Drugs used in Treatment HTN 1.Diuretics 2.Sympatholytics 3.Calcium channel blocker 4.Angiotensin converting enzyme inhibitirs (ACE-I) 5.Angiotensin 2 receptor blockers 6.Vasodilators

Drugs used to treat HTN will affect one of these parameters COTPR SV HR PreloadContractility Venous tone Intravascular volume Na\H2O retention BP

Drugs used to treat HTN will affect one of these parameters TPRCO Direct innervation Circulating regulators Local reglators BP

Drugs that reduce CO Drugs that reduce SV – Drugs that reduce contractility Beta blockers CCB (NDHP) – Drugs that reduce preload Drugs that decrease venous tone – Alpha 1nblockers – Sodium nitroprusside – ACE inhibitors – AT1 antagonist Drugs that decrease intravascular volume – Diuretics – ACE inhibitors – AT1 antagonist

Drugs that reduce CO Drugs that reduce HR – Beta blockers – CCB

Drugs that reduce TPR Drugs that affect smooth muscle contraction – CCB – Direct arteriolar vasodilators Drugs that affect direct innervation – Alpha 1 blockers – Central alpha 2 agonist Drugs that affect circulating regulators – Alpha 1 blockers – Central alpha 2 agonist – ACE inhibitors – AT1 antagonist Drugs that affect local regulators – Endothelin antagonist – ACE inhibitors – AT1 antagonist – Na nitroprusside

1.Diuretics Hydrochlorothiazide Furosamide Combination HCT+amiloride Spironolactone in HTN caused by hyper aldosteronism REVIEW DIURETICS LECTURE

Diuretics and HTN Diuretics is useful in volume based HTN HCT is the first line of treatment why? Loop diuretics is preferred over thiazide in these situations 1.Volume based HTN with renal insufficiency 2.Malignant HTN Spironolactone is preferred in HTN induced by hyperaldosteronism

2. Sympatholytics 1.Ganglionic blockers :trimethaphan (last line TMT ) 2.A1 blocker :prazocin,doxazocin – Was previously used in HTN – Very useful in patients suffering from BPH and HTN 3.A2 agonist :clonidine,methyldopa – Methyldopa is th drug of choice for pregnant women with HTN 4. B blocker : atenolol,propranolol – B1 selective is preferred – Review their contraindications ! REVIEW SYMPATHETIC NERVOUS SYSTEM LECTURES

B blocker A,b non selective CarvidilolLabetolol B1,b2 non selective PropranololTimolol B1 selective AtenololEsmolol

Beta Blockers Labetolol is available in IV form and it is limited to treat HTN emergencies

Side effects – Tiredness – Cold hands and feet Because of vasoconstriction of blood vessels – Impotence and sexual dysfunction – May mask the effect of hypoglycemia in DM – Dyslipidemia how to correct this SE? Beta Blockers

B blocker Relative contraindications – Asthma/COPD – Decompensated CHF – Raynaud’s phenomenon – Peripheral vascular disease – Depression

Calcium channel blocker(CCB) Nifedipine Amlodipine Verapamil Diltiazem

Calcium Channel Antagonists Direct vasodilators Used in combination with other antihypertensive drugs Avoid in patients with Congestive Heart Failure (especially short duration DHP) Most common side effects – Constipation – Peripheral edema – Headache – Exacerbate myocardial ischemia

ACE-I Captopril Enalapril Ramipril

ACE (angiotensin converting enzyme) Inhibitors First line TMT Method of action – Block the enzyme that converts angiotensin I to angiotensin II ( a vasoconstrictor) – Promote vasodilatation – Lowers aldosterone secretion Especially useful – HTN with CHF or DM

Side effects – Dry Cough Accumulation of bradykinin – Rash – Angioneurotic edema – Taste disturbance – Hyperkalemia ACE-I

Contraindications – Pregnancy – Bilateral renal artery stenosis – Athma – COPD’s ACE-I

Angiotensin receptor antagonist Valsartan Losartan

Angiotensin receptor blockers Method of action – Block the AT2 receptor causing a fall in peripheral resistance Very similar to ACE inhibitors but does not cause a cough why?

Vasodilators Vasodilators K channel opener Minoxidil Hydralazine Donors of NO Nitrates Sodium nitroprusside CCB Alpha 1 antagonist ACE-I and AT1 blockers

Vasodilators Hydralazine Minoxidil Sodium nitroprusside

Hydralazine PO Direct vasodilation of arteriolar smooth muscle decrease TPR The decrease in TPR cause : – Reflex tachycardia – Sodium water retention Use of beta blockers minimize these symp. effects Clinical uses: 1.Hypertension 2.Congestive heart failure Used in combination with nitrates

Hydralazine side effects Lupus like syndrome Cardiovascular effects – Hypotension – Tachycardia – Palpitation – Angina Headache Nausea Diarrhea

Minoxidil Direct vasodilation of arteriolar smooth muscle decrease TPR The decrease in TPR cause : – Reflex tachycardia – Sodium water retention Use of beta blockers minimize these symp. effects It works by opening of potassium channels

Minoxidil Clinical uses: 1.Severe HTN 2.Hair replacement (bladness) Side effects: 1.Cardiovascular effects Hypotension Tachycardia Palpitation Angina 2.Headache 3.Hypertrichosis

Sodium nitroprusside Vasodilatation of arteriolar and venous smooth muscle decrease TPR Vasodilataion mediated by NO production Works by releasing nitric oxide It has short duration of action and rapid onset of action It is available as intravenous infusion

Sodium nitroprusside Clinical uses: 1.HTN emergencies 2.Severe HF Side effects: 1.Cyanide toxicity 2.Thiocyanate toxicity 3.Cardiovascular effects Hypotension Tachycardia Palpitation Angina 4.Headach Cardiac arrhythmia,acid base imbalance and death Convulsions,muscle spasm

Hypertension management High blood pressure is a lifelong disease and need lifelong TMT – Except if it was secondary HTN and we treat the underlying cause Blood pressure can be controlled not cured Controlling blood pressure will reduce the risk of stroke, heart attack, heart failure and kidney disease

HTN management : Non pharmacological treatment Lifestyle modification is always recommended but is frequently inadequate on its own – Salt restriction to 4 grams per day The antihypertensive effect of many medicines is enhanced by sodium restriction – Weight loss to within 15% of ideal body weight is the goal Although as little as a 10 lb loss may decrease BP significantly – Alcohol restriction – Regular exercise even without weight loss – Reduce all other cardiovascular risk factors

Hypertension management: drug therapy If the patient is not suffering from severe hypertension begin with single drugchoosing one of these – ACE –I is the best choic if there wasn’t contraindications – Thiazide diuretic – Beta blockers If the BP remains uncontrolled add another agent see the next slide

ACE-IAdd thiazide diureticAdd BETA 1 blocker Add CCB Assess compliance and search for secondary causes Add another antiadrenergic agent (clonidine),vasodilator (hydralazine) Uncontrolled Continue therapy Reduce dose of the initial drug Reduce dose of the beta blocker Continue thearapy Continue therapy Controlled

Disease processes which are affected by anti-hypertensive drugs: Diabetes – Beta-blockers and thiazide diuretics may make glycemic control difficult. ACE inhibitors can protect the kidney. Coronary Artery Disease – Beta-blockers offer a mortality benefit (in general). Short-acting calcium channel blockers can worsen ischemia

Disease processes which are affected by anti-hypertensive drugs: Congestive Heart Failure (compensated vs. un- compensated) – Beta-blockers offer a mortality benefit as do ACE inhibitors. Beta- blockers should not be used in uncompensated CHF. Hyperlipidemia – Beta-blockers and thiazide diuretics may affect lipid profile unfavorably. COPD/Asthma – Beta-blockers need to be used with caution.

Disease processes which are affected by anti-hypertensive drugs: Renal Failure – ACE inhibitors may cause a reduction in renal performance Pregnancy – ACE inhibitors and ARB’s are contraindicated. Aortic Stenosis – Vasodilators need to be introduced with caution. Hyperuricemia (Gout) – Thiazide diuretics may increase uric acid levels

Disease processes which are affected by anti-hypertensive drugs: Benign Prostatic Hypertrophy – Alpha-1 blockers can provide symptomatic improvement. Depression – Beta-blockers may exacerbate. Raynaud’s Syndrome – Beta-blockers may exacerbate.

Disease processes which are affected by anti-hypertensive drugs: Peripheral Vascular Disease (with Symptoms) – Beta-blockers need to be used with discretion. Renal Artery Stenosis (bilateral vs. unilateral) – ACE inhibitor or ARB’s are relatively contraindicated. Cardiac Conduction Defects – Beta-blockers, diltiazem and verapamil can exacerbate conduction defects.

What is the malignant hypertension? Clinical syndromes characterized by severe(typically acute) elevation in BP and this abrupt increase in BP associated with target organ vascular damage – Retinal hemorrhage – encephalopathy – Renal insufficiency – Left ventricular failure Life threatening condition

How we can treat it? Intravenous antihypertensive agents – Labetalol – Sodium nitroprusside – Furosemide  The goal is not normalization of BP  Because sudden hypoperfusion may result in brain injury Excess fluid may be removed with loop diuretics

Demographic factors that affect drug therapy selection for the HTN patients Elderly people – Maximum response seen with Diuretics CCB – Beta blockers cause AV node blockage and MI – They have decreased levels of renin so they show little response to ACE-I

African people – Maximum response seen with Diuretics CCB – Beta blockers show little response Mutation in beta receptors – They have decreased levels of rennin so they show little response to ACE-I Demographic factors that affect drug therapy selection for the HTN patients