Cardio: antiHTN, Ca, NO, etc. Flashcards Preview

Pharmacology > Cardio: antiHTN, Ca, NO, etc. > Flashcards

Flashcards in Cardio: antiHTN, Ca, NO, etc. Deck (27)
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1

Antihypertensive therapy: 
Primary (Essential) HTN

  • Diuretics
  • ACE inhibitors
  • Angiotensin II receptor blockers (ARBs)
  • Ca2+ channel blockers

2

Antihypertensive therapy: 
Hypertension with CHF

  • Diuretics
  • ACE inhibitors
  • ARBs
  • β-blockers (compensated CHF) (cautiously in decompensated CHF and contraindicated in Cardiogenic Shock)
  • Aldosterone antagonists

3

Antihypertensive therapy: 
Hypertension with Diabetes mellitus

  • Diuretics
  • ACE inhibitors
  • ARBs
  • Ca2+ channel blockers
  • β-blockers
  • α-blockers
     
  • ACE inhibitors and ARBs are protective against diabetic nephropathy

4

Ca2+ channel blocker drugs

  • Verapamil (non-dihydropyridine)
  • Diltiazem
  • Nifedipine (dihydropyridine)
  • Amlodipine
  • Nimodipine

5

Ca2+ channel blocker: Mechanism

  • Blocks voltage-dependent L-type Ca2+ channels of cardiac muscle and blood vessels ("-dipines")
    → ↓ [Ca2+]
    → ↓ Contactility, CO (Verapamil and Ditiazem),
    → ↓ TPR (acll CCBs)
  • Vascular smooth muscle:
    • Amlodipine, Nifedipine > Diltiazem > Verapamil
  • Heart:
    • Verapamil > Diltiazem > Amlodipine, Nifedipine

6

Ca2+ channel blocker: Clinical Use

  • Nifedipine (dihydropyridine) (except Nimodipine)
    • HTN, Angina (including Prinzmetal), Raynaud phenomenon,
    • Antiarrhythmics (only use Verapamil, Diltiazem)
  • Verapamil (Non-dihydropyridine)
    • HTN, Angina, Atrial fibrillation / flutter
  • Nimodipine
    • Subarachnoid hemorrhage (prevents cerebral vasospasm)

7

Ca2+ channel blocker: Toxicity

  • Reflex tachycardia ("-dipines")
  • ☆ Gingival hyperplasia ("-dipines") (Gum problems)
    • ​Phenytoin (CNS acting drug)
  • Constipation (Verapamil)
  • Cardiac depression
  • AV block
  • Peripheral edema
  • Flushing
  • Dizziness
  • Hyperprolactinemia (high levels of prolactin in blood)

8

Hydralazine: Mechanism

  • Increases cGMP --> smooth muscle relaxation
  • Vasodilates arterioles > veins
  • Afterload reduction

9

Hydralazine: Clinical Use

  • Severe HTN
  • CHF
  • First-lne therapy for HTN in pregnancy w/ methyldopa
  • Frequently coadministered with a β-blocker to prevent reflex tacycardia

10

Hydralazine: Toxicity

  • Compensatory tachycardia (contraindicated in Angina / CAD)
  • Fluid retention
  • Nausea
  • Headache
  • Angina
  • SLE-like syndrome

11

Hypertensive Emergency Drugs

  • Commonly used drugs include:
    • Nitroprusside (NO)
    • Fenoldopam (D1)
    • Nicardipine (Dihydro CCB)
    • Clevidipine (Dihydro CCB)
    • Labetalol (α1, β1, β2 -blocker)

12

Nitroprusside: Mechanism

  • Short acting
    • Increases cGMP via direct release of NO​
    • Can cause cyanide toxicity (releases cyanide)

13

Fenoldopam: Mechanism

  • Dopamine D1 receptor agonist --> vasodilation
    • Coronary
    • Peripheral
    • Renal
    • Splanchnic 
  • Decreases Blood Pressure
  • Increases Natriuresis (excreting Na in urine w/ Kidneys)

14

Mechanism of Nitroglycerin, Isosorbide dinitrate:

  • Vasodilate by ↑ NO in vascular smooth muscle→ ↑ in cGMP and smooth muscle relaxation
  • Dilate veins >> arteries → ↓ Preload

15

Clincal use of Nitroglycerin, Isosorbide dinitrate:

  • Angina
  • Acute Coronary syndrome
  • Pulmonary edema

16

Toxicity of Nigroglycerin, Isosorbide dinitrate:

  • Reflex tachycardia (treat with β-blockers)
  • Hypotension
  • Flushing
  • Headache
  • "Monday disease" - in industrial exposure: development of tolerance for the vasodilating action during the work week and loss of tolerance over the weekend results in tachycardia, dizziness, and headache upon reexposure

17

Goal of Antianginal therapy

  • Reduction of myocardial O2 consumption (MVO2) by ↓ in one or more of the determinants of MVO2:
    • End-diastolic volume
    • Blood pressure
    • Contractility
    • Heart rate

18

Effect of Nitrates on Preload:

  • End-diastolic Volume: ↓
  • Blood Pressure: ↓
  • Contractility: ↑ (reflex response)
  • Heart Rate: ↑ (reflex response)
  • Ejection time: ↓
  • MVO2: ↓
     
  • Calcium channel blockers - Nifedipine is similar to Nitrates in effect

19

Effect of β-blockers on Afterload:

  • End-diastolic Volume: ↑
  • Blood Pressure: ↓
  • Contractility: ↓
  • Heart Rate: ↓
  • Ejection time: ↑
  • MVO2: ↓
     
  • Verapamil is similar to β-blockers in effect
  • Pindolol and Acebutolol - partial β-agonists contraindicated in angina

20

Effect of Nitrates + β-blockers:

  • End-diastolic Volume: No effect or ↓
  • Blood Pressure: ↓
  • Contractility: Little / No effect
  • Heart Rate: ↓
  • Ejection time: Little / No effect
  • MVO2: ↓↓

21

Adverse effects common to all ACE inhibitors:

  • Dry cough
  • Angioedema (rarely)
  • Hypotension
  • Hyperkalemia

22

Adverse effects common to all ARBs:

  • Dizziness
  • Hyperkalemia

23

Diuretic agents:

  • Thiazide diuretics - mild to moderate HTN
  • Loop diuretics - used in combination with sympatholytic agents
  • Potassium-sparing agents - used with digoxin (cardiac glycosides)

24

  • β-Adrenocepter antagonist
  • Antagonizes catecholamine action at both β1- and β2-receptors
  • Sustained reduction in peripheral Vascular Resistance
  • Blockade of β1-adrenoreceptors reduces heart rate and contractility
  • Blockage of β2-adrenoreceptors increases Airway resistance and decreases Catecholamine glycogenolysis and Peripheral vasodilation
  • β- in CNS decreases Sympathetic activity
  • Decreases Renin release

Propranolol (Inderal)

Used w/ mild to moderate Hypertension

25

Antihypertensive therapy: 
Hypertension with Angina

  • Diuretics
  • ACE inhibitors
  • ARBs
  • β-blockers
  • CCBs

26

Antihypertensive therapy: 
Hypertension with post-MI

  • Diuretics
  • ACE inhibitors
  • ARBs
  • β-blockers

27

Antihypertensive therapy: 
Hypertension with Dyslipidemias

  • Diuretics
  • ACE inhibitors
  • ARBs
  • α-blockers
  • β-blockers
  • CCBs