Term
| What are the 4 Antiarrhythmic Classes of Drugs? |
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Definition
Class I - Na+ Channel Blockers
Class II - Beta Blockers
Class III - K+ Channel Blockers
Class IV - Ca++ Channel Blockers |
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Term
| What are the Class I Drugs? |
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Definition
Class IA:
-Qunidine
-Procainamide
-Disopyramide
Class IB:
-Lidocaine
-Mexilitine
-Tocainide
-Phenytoin
Class IC:
-Flecainide
-Propafenone
-Moricizine |
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Term
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Definition
MECH: Blocks Na+ channels; greater blockade in tissues already being depolarized; Slows Phase 0 depolarization
CLIN: Ventricular arrhythmias
SE: Lidocaine causes CNS toxicity |
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Term
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Definition
Propranolol
MECH: Decreases Phase 4 depolarization; decreases HR and contractility
CLIN: Decreases sudden arrhythmic death Post-MI |
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Term
| What are the Class III Drugs? |
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Definition
-Amiodarone
-Dronedarone
-Sotalol
-Bretylium
-Ibutilide |
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Term
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Definition
MECH: Blocks everything; Increases AP, ERP, QT; reduced ability to respond to tachycardia
CLIN: Tx of VT, VF, AFib; prevention of AFib Post-Op
PHARM-K: Onset 2-3 days; Very long half-life (SE up to 3 months after D/C of drug)
SE: Vasoconstriction, Brady, Hypotension, Pulmonary symptoms, Hyper/Hypo-Thyroid, Malaise, N/V, Photosensitivity, corneal deposits
--Should not be given in combo with: Beta-Blockers, diltiazem, verapamil |
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Term
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Definition
PHARM-K: Short half-life
CLIN: Similar to Amiodarone but less SE; Tx of AFib
SE: GI disturbance, Prolonged QT, hepatic failure |
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Term
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Definition
| CLIN: Tx of Sustained VT or VF |
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Term
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Definition
| CLIN: Life-threatening ventricular arrhythmias |
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Term
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Definition
| CLIN: Chemical cardio-version of AFib and AFlutter |
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Term
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Definition
Diltiazem
MECH: Ca++ channel blockers; decrease conduction velocity and increase ERP
CLIN: Converts AV nodal reentry; Rate controlling drugs for AFib and AFlutter
SE: Decreased cardiac contractility, decreased AV conduction, Decreased BP |
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Term
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Definition
MECH: Slows AV node; Hyperpolarizes the tissue; Reduces Ca++ current
PHARM-K: Half-life of seconds
CLIN: Tx of AV nodal arrhythmias; Diagnostic for AFib/AFlutter
--Caffeine and Methylxanthines block adenosine effects |
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Term
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Definition
Digoxin
MECH: Selectively and reversibly inhibits the Na+/K+ ATPase ion transport system. Results in rise of intracellular Na+ and Ca++
PHARM-K: Half-Life 36-40 hrs; Narrow Therapeutic Window: 0.8 - 2.0
CLIN: CHF - Improves fxn but does not prolong survival
AFib - Reduces conduction velocity; decreases refractory period
SE: Dig Tox: Arrhythmias, N/V, vision disturbance
--Tx of DigTox: Digibind, correct electrolytes |
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Term
| What are the Beta-Agonist Drugs? |
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Definition
-Dobutamine
-Dopamine
-Epinephrine
-Norepinephrine |
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Term
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Definition
MECH: B1>B2 Stimulation
B1 Effects: increased contractile force, increased CO
B2 Effects: Peripheral vasodilation
CLIN: Acute cardiogenic shock/failure |
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Term
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Definition
CLIN: Varies By Dosage
-0.5-2.0: D1 = Increased Renal and Mesenteric Blood Flow
-2-10: B1 = Increased Contractility and Increased CO
-10-20: A and B1 = Predominant A effect and vasoconstriction; Tx of Shock |
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Term
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Definition
CLIN: Varies By Dosage
-Low Concentration: B Predominant
B1 Effect: Increases contractile force, CO, cardiac O2
B2 Effect: Peripheral vasodilation, Increased skeletal blood flow, bronchial smooth muscle relaxation
-High Concentration: A1 Predominant
Vasoconstriction and Anaphylactic Shock |
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Term
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Definition
MECH: A1 = A2 > B1 >> B2; decreased renal blood flow, increased vascular resistance, increased O2 consumption
CLIN: Tx of Shock
SE: reflex brady |
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Term
| Phosphodiesterase Inhibitors |
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Definition
Milrinone
MECH: Increases cardiac contractility and vasodilation
CLIN: Short term support for heart failure
SE: hypotension, ventricular arrhythmias, RENAL DOSING |
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Term
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Definition
-Nitroglycerin (NTG)
-Isosorbide Dinitrate (ISDN)
-Isosorbide Mononitrate (ISMN)
-Sodium Nitroprusside |
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Term
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Definition
MECH: Vascular Smooth Muscle Relaxation
PHARM-K: NTG has significant 1st-Pass metabolism; NTG Half-Life - ~1min; ISDN ~1hr; ISMN ~2-4hrs
Venous dilation > Arterial
CLIN: Angina, HTN, CHF
SE: Hypotension, HA, Pts can develop tolerance [Pts should have a "nitrate free interval" - 6-8 hrs] |
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Term
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Definition
MECH: Vascular smooth muscle relaxation
PHARM-K: Short half-life, continuous infusion required; Arterial and Venous Dilation are EQUAL
CLIN: Hypertensive Emergency/Urgency, Decompensated Heart failure
SE: Hypotension and Cyanide poisoning |
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Term
| What are the Phosphodiesterase Inhibitors? |
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Definition
-Sildenafil
-Vardenafil
-Tadalafil |
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Term
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Definition
MECH: Penile Erection and some effects in the systemic and pulmonary vasculature
CLIN: ED and Pulmonary HTN; Sildenafil can be used for infants with HTN
SE: HA, flushing, hypotension; ALL are contraindicated with the use of nitrates |
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Term
| What are the Calcium channel blockers? |
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Definition
Dihydropyridines:
-Amlodipine
-Felodipine
-Nifedipine
Non-Dihydropyridines
-Diltiazem
-Verapamil |
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Term
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Definition
MECH: Predominantly arteriolar dilators
Vasculature: Decreases smooth muscle contractility
Myocardium: Decreased contractility, decreased SA node pacemaker, decreased AV node conduction
CLIN: Dihydropyridines: Angina and HTN
Non-Dihydropyridines: AFlutter/AFib and HTN
SE: Dihydropiridines: Constipation and Peripheral Edema
Non-Dihydropiridines: Constipation and Peripheral Edema, Bradycadia and AV block |
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Term
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Definition
Minoxidil
MECH: Direct arterial vasodilation; smooth muscle contraction inhibited
CLIN: Refractory HTN, Hypertrichosis
SE: Na+ and H2O retention (edema); reflex tachy, flushing |
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Term
| Endothelin Receptor Antagonists |
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Definition
Bosentan
MECH: Competitive antagonist of ETa and ETb; causes vasodilation
CLIN: Pulmonary HTN
SE: Hepatic toxicity; teratogenic |
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Term
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Definition
MECH: Direct arteriolar vasodilation
PHARM-K: Frequent dosing (every 6-8 hrs)
CLIN: HTN and CHF (commonly in combo with a nitrate)
SE: Lupus-Like syndrome |
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Term
| Beta-Adrenergic Antagonists |
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Definition
Labetalol and Carvedilol
MECH: Nonselective B1, B2 and A1 receptor blockers
CLIN: HTN, CHF, AMI
--All other blockers can work on HTN, but they focus on HR. These two drugs work on vascular tone to reduce BP. |
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Term
| Alpha-Adrenergice Antagonists |
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Definition
Prazosin
Terazosin
Doxazosin
MECH: Selectively block A1 receptors in the arterioles and venules leading to vasodilation
CLIN: BPH, HTN
SE: Dizziness, Orthostatic HTN |
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Term
| What are the Four main systems that regulate volume? |
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Definition
-Natriuretic Peptides
-Renal sympathetic nerves
-Renin-angiotensin-aldosterone system (RAAS)
-Antidiuretic Hormone (ADH) |
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Term
| Recombinant Natriuretic Peptide |
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Definition
Nesiritide
MECH: Causes stimulation of Na+ and H2O loss in kidneys, suppression of thirst, inhibition of antagonistic hormones, dilation of blood vessels
PHARM-K: Half-Life of 18 min (continuous infusion)
CLIN: HTN
SE: Hypotension |
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Term
| What are the ACE Inhibitors? |
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Definition
-Captopril
-Enalapril
-Lisinopril
-Fosinopril
-Ramipril |
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Term
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Definition
PHARM-K: Pro-drugs requiring hydrolysis for activation; take on an empty stomach
CLIN: Heart failure
SE: Postural hypotension, renal insufficiency, hyperkalemia, angioedema -- stop drug and never start again -- persistent cough, teratogenicity |
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