Cardio: antiHTN, Ca, NO, etc.

Question 1

Antihypertensive therapy:
Primary (Essential) HTN

Answer 1

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

Question 2

Antihypertensive therapy:
Hypertension with CHF

Answer 2

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

Question 3

Antihypertensive therapy:
Hypertension with Diabetes mellitus

Answer 3

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

Question 4

Ca²⁺ channel blocker drugs

Answer 4

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

Question 5

Ca²⁺ channel blocker: Mechanism

Answer 5

• 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

Question 6

Ca2+ channel blocker: Clinical Use

Answer 6

• 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)

Question 7

Ca²⁺ channel blocker: Toxicity

Answer 7

• 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)

Question 8

Hydralazine: Mechanism

Answer 8

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

Question 9

Hydralazine: Clinical Use

Answer 9

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

Question 10

Hydralazine: Toxicity

Answer 10

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

Question 11

Hypertensive Emergency Drugs

Answer 11

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

Question 12

Nitroprusside: Mechanism

Answer 12

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

Question 13

Fenoldopam: Mechanism

Answer 13

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

Question 14

Mechanism of Nitroglycerin, Isosorbide dinitrate:

Answer 14

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

Question 15

Clincal use of Nitroglycerin, Isosorbide dinitrate:

Answer 15

• Angina
• Acute Coronary syndrome
• Pulmonary edema

Question 16

Toxicity of Nigroglycerin, Isosorbide dinitrate:

Answer 16

• 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

Question 17

Goal of Antianginal therapy

Answer 17

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

Question 18

Effect of Nitrates on Preload:

Answer 18

• 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

Question 19

Effect of β-blockers on Afterload:

Answer 19

• 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

Question 20

Effect of Nitrates + β-blockers:

Answer 20

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

Question 21

Adverse effects common to all ACE inhibitors:

Answer 21

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

Question 22

Adverse effects common to all ARBs:

Answer 22

• Dizziness
• Hyperkalemia

Question 23

Diuretic agents:

Answer 23

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

Question 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

Answer 24

Propranolol (Inderal)

Used w/ mild to moderate Hypertension

Question 25

Antihypertensive therapy:
Hypertension with Angina

Answer 25

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

Question 26

Antihypertensive therapy:
Hypertension with post-MI

Answer 26

• Diuretics
• ACE inhibitors
• ARBs
• β-blockers

Question 27

Antihypertensive therapy:
Hypertension with Dyslipidemias

Answer 27

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