Cardiovascular Medicine Book

Congestive Heart Failure

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Hyperlipidemia

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Beta BlockerAka: Beta-Blocker, Beta Adrenergic Antagonist, Beta Adrenoceptor Blocking Drug, Atenolol, Timolol, Nadolol

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  1. History: Sir James Black and Propranolol
    1. Sir James Black won 1988 Nobel Prize for Propranolol
    2. Synthesized Propranolol first in the 1960's
    3. Revolutionized cardiovascular medicine
  2. Indications
    1. Hypertension
    2. Myocardial Infarction or Coronary Artery Disease
    3. Atrial Fibrillation Rate Control
    4. Stable Congestive Heart Failure (Carvedilol, Metoprolol, Bisoprolol)
    5. Arrhythmia refractory to other modality
      1. Recurrent Ventricular Tachycardia
      2. Recurrent Ventricular Fibrillation
    6. Migraine Prophylaxis
  3. Contraindications
    1. Reactive Airway Disease (Asthma, COPD)
      1. Cardioselective beta blockers are not contraindicated
      2. See Bronchospasm under adverse effects below
    2. Acute Congestive Heart Failure exascerbation
    3. Concurrent Calcium Channel Blocker use
  4. Mechanism
    1. Beta Adrenergic Receptor Antagonist
      1. Blocks Beta Adrenergic Receptors
      2. Inhibits effects of circulating Catecholamines
    2. General Cardiac Effects
      1. Negative Inotrope
        1. Reduces Myocardial Contractility
      2. Negative Chronotrope
        1. Reduces Heart Rate
      3. Reduces Blood Pressure
      4. Reduces Myocardial Oxygen Demand
    3. Antiarrhythmic effects
      1. Seen with non-selective Beta Blockers (Propranolol)
      2. Controls Catecholamine stimulated arrhythmias
        1. Recurrent Ventricular Tachycardia
        2. Recurrent Ventricular Fibrillation
      3. Controls Myocardial Ischemia related arrhythmias
      4. Reduces AV Nodal Conduction
        1. Slows ventricular response
          1. Atrial Fibrillation
          2. Atrial Flutter
          3. Paroxysmal Supraventricular Tachycardia
        2. Quinidine-like effect on action potential
          1. Seen with Propranolol
    4. Myocardial protection
      1. Reduces Myocardial Infarction size
      2. Prevents re-infarction after Thrombolytic
    5. Non-Selective effects (Beta 2 Adrenergic Receptor)
      1. Results in bronchoconstriction
      2. Non-Selective Beta Blockers (e.g. Propranolol)
      3. Selective Beta Blockers lose selectivity at high dose
        1. High dose Metoprolol (over 200 mg/day)
        2. High dose Esmolol (over 300 ug/kg/min)
  5. Adverse Effects
    1. SA and AV nodal blockade
      1. Avoid in over age 75 unless secondary indication
      2. Do not use with Calcium Channel Blockers
    2. Hypotension or Orthostasis
    3. Congestive Heart Failure
      1. Treat with vasodilators and Diuretics with inotropes
    4. Bradycardia
      1. Treat with Atropine, Transcutaneous pacing, Dopamine
    5. Bronchospasm
      1. Treat with Sympathomimetics and Aminophylline
      2. Unlikely to occur in cardioselective beta blockers
        1. Study looked at atenolol, Metoprolol, bisoprolol
        2. First dose may lower FEV1 (responds to Albuterol)
        3. Continuous use does not impair lung function
        4. Salpeter (2002) Ann Intern Med 137:715
    6. Major Depression exacerbation
    7. Fatigue
  6. Drug Interactions: Decreased Heart Rate and AV Conduction
    1. Amiodarone
    2. Diltiazem
    3. Verapamil
    4. Propafenone (Rythmol)
    5. Sotalol (Betapace)
  7. Preparations: Cardioselective
    1. Atenolol (Tenormin)
      1. Not as effective as other beta blockers in cardiovascular disease prevention
        1. Consider Metoprolol or Nadolol instead
        2. Carlberg (2004) Lancet 364:1684
      2. Dosing
        1. Regular: 50 mg PO daily (MAX: 100 mg/day)
        2. IV (Acute MI): 5 mg IV over 5 min, repeat in 10 min
    2. Bisoprolol
      1. Most cardioselective of beta blockers
    3. Metoprolol (Lopressor)
    4. Esmolol Hydrochloride (Brevibloc)
    5. Nebivolol (Bystolic)
      1. Third generation beta blocker with vasodilatory properties (nitric oxide release)
  8. Preparations: Nonselective
    1. Propranolol (Inderal)
    2. Carvedilol (Coreg)
      1. Third generation beta blocker with vasodilatory properties (alpha blocker)
    3. Timolol (Blocadren)
      1. Dose: 10 mg PO bid (MAX 60 mg/day)
    4. Nadolol (Corgard)
      1. Dose: 40 mg PO qd (MAX 320 mg/day)

Adrenergic beta-Antagonists (C0001645)

Definition (MSH)Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety.
Definition (NCI)Natural or synthetic Beta Adrenergic Blocking Agents typically bind to - but do not activate - beta-adrenergic receptors, blocking or diminishing physiologic beta-adrenergic agonist actions and activation of the sympathetic system. Reducing cardiac output, beta adrenergic antagonists are generally used for treatment of hypertension, cardiac arrythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. (NCI04)
ConceptsPharmacologic Substance (T121)
EnglishADREN BETA ANTAG, ADREN BETA RECEPT BLOCK, ADRENERGIC ANTAGONISTS BETA, Adrenergic beta Antagonists, adrenergic beta receptor blockaders, ADRENERGIC RECEPTOR BLOCKADERS BETA, BETA ADREN BLOCK, BETA ADREN BLOCK AGENTS, BETA ADREN RECEPT BLOCK, beta Adrenergic Blockers, beta Adrenergic Blocking Agents, beta Adrenergic Receptor Blockaders, beta blocker, Beta blockers, BETA BLOCKERS ADREN
Spanishagente betabloqueante, antiadrenérgicos beta, antiadrenergicos beta, betabloqueantes, bloqueantes beta
CreditsDerived from the NIH UMLS (Unified Medical Language System)


Atenolol (C0004147)

Definition (MSH)A cardioselective beta-adrenergic blocker possessing properties and potency similar to PROPRANOLOL, but without a negative inotropic effect.
Definition (CSP)l-p-carbamoylmethylphenoxy-3-isopropylamino -2-propanol, is a peripheral beta blocker used as an antihypertensive; propranolol, by contrast, also has CNS effects.
Definition (NCI)A synthetic isopropylamino-propanol derivative used as an antihypertensive, hypotensive and antiarrhythmic Atenolol acts as a peripheral, cardioselective beta blocker specific for beta1-receptors, without intrinsic sympathomimetic effects. It reduces exercise heart rates and delays atrioventricular conduction, with overall oxygen requirements decreasing. (NCI04)
ConceptsOrganic Chemical (T109) , Pharmacologic Substance (T121)
EnglishAtenolol, ATENOLOL PREPARATION
Spanishatenolol
CreditsDerived from the NIH UMLS (Unified Medical Language System)


Nadolol (C0027302)

Definition (MSH)A non-selective beta-adrenergic antagonist with a long half-life, used in cardiovascular disease to treat arrhythmias, angina pectoris, and hypertension. Nadolol is also used for MIGRAINE DISORDERS and for tremor.
Definition (NCI)A non-selective beta-adrenergic antagonist with antihypertensive and antiarrhythmic activities. Nadolol competitively blocks beta-1 adrenergic receptors located in the heart and vascular smooth muscle, therefore inhibiting the effects of catecholamines, epinephrine, and norepinephrine. As a result, this agent produces negative inotropic and chronotropic effects. Nadolol exerts its antiarrhythmic effect via impairment of atrioventricular (AV) node conduction and reduction of sinus rate. In addition, nadolol blocks beta-2 adrenergic receptors located in the bronchiole smooth muscle resulting in vasoconstriction. Furthermore, beta-2 receptor blockage within the juxtaglomerular apparatus leads to the inhibition of renin production, as well as subsequent reduction in angiotensin II and aldosterone levels, thereby inhibiting angiotensin II and aldosterone dependent vasoconstriction and water retention.
ConceptsOrganic Chemical (T109) , Pharmacologic Substance (T121)
EnglishNadolol, NADOLOL PREPARATION
Spanishnadolol
CreditsDerived from the NIH UMLS (Unified Medical Language System)


Timolol (C0040233)

Definition (MSH)A beta-adrenergic antagonist similar in action to PROPRANOLOL. The levo-isomer is the more active. Timolol has been proposed as an antihypertensive, antiarrhythmic, antiangina, and antiglaucoma agent. It is also used in the treatment of MIGRAINE DISORDERS and tremor.
Definition (NCI)A propanolamine derivative and a non-selective beta-adrenergic antagonist with antihypertensive property. Timolol competitively binds to beta-1-adrenergic receptors in the heart and vascular smooth muscle and beta-2-receptors in the bronchial and vascular smooth muscle, resulting in a decrease in beta-adrenergic stimulation. Beta-1-receptor blockade results in a decrease in resting and exercise heart rate and cardiac output, a decrease in both systolic and diastolic blood pressure, and, possibly, a reduction in reflex orthostatic hypotension. Beta-2-blockade results in an increase in peripheral vascular resistance. The ultimate results include vasodilation, and negative chronotropic and inotropic cardiac effects. In addition, timolol reduces intra-ocular pressure possibly by decreasing aqueous humor production by reduction of blood flow to the ciliary processes and cAMP synthesis.
ConceptsOrganic Chemical (T109) , Pharmacologic Substance (T121)
EnglishTimolol, TIMOLOL PREPARATION
Spanishtimolol
CreditsDerived from the NIH UMLS (Unified Medical Language System)



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