RMP: -60 to -70 mV

Propagation speed: <0.1 m/s

EWA: 70-80

40 HBM

RMP: -80 to -90 mV

Propagation speed: <0.3-0.4 m/s

EWA: 110-120

RMP: -90 to -95 mV

Propagation speed: 2-3 m/s

EWA: 120

20 HBM

TTX and Local anesthetics are inhibitors of:

Rapid depolarization phase in A, V and Purkinje.

Depolarization phase in SA, AV node -> contraction

Repolarization phase in the AP.

Na channels blockers in the phase 0 and 1. Causing ⬇ of phase 0 depolarization and ⬇Conduction of velocity.

Class I block open Na channels, prolonged AP, and refractory periods.

Class I block inactivated Na channels, and shorten AP, and refractory periods.

Class I block open Na channels -> ⬇ phase 0

Procainamide, Quinidine and Disopyramide are class I:

Licodaine and Mexiletine are class 1:

Flecainide and Propafenone are class I:

B-Blockers that work on phase 0 and 4 ⬇ SN automaticity, ⬇AV conduction, ⬇ HR and ⬇ contractility.

Atenolol, Esmolol and metoprolol are class:

K channels Blockers that work on phase 1, 2 and 3, ⬆AP, ⬆ refractory period, ⬆AV conduction, ⬇ HR and ⬇ Ca.

Amidarone, Dofetilide, Dronedarone, Ibultilide and Sotalol are class:

CCB in phase 0, 1, 2 and 3 are class:

Verapamil and Diltiazem are class:

Digoxin blocks phase at K binding site:

Ivabradine blocks phase:

MAO: (-) Voltage-gated Na channels -> (-) ion influx -> (-) initiation and conduction of impulses.

Adverse effects: convulsions, bradycardia, arrhythmias and cardiac arrest.

+ Sulfasalazine= methemoglobinemia

MAO:

1. Prolonged repolarization phase 3 (K channel) of AP

2. (-) Beta receptors -> ⬇ AV and Sinus node conduction

Its metabolism of is inhibited by grapefruit juice

Adverse effects: Hepatitis, exacerbation of asthma and congestive failure, and pneumonitis.

Reversible cardiac effects: bradycardia, impaired AV conduction, and QT interval prolongation leading to torsades de pointes. Photosensitivity, blue-gray skin discoloration. Thyrotoxicosis & hypothyroidism. Neuropathy.

+ Atropine: The risk or severity of QTc prolongation

MAO: (+) A1 and A2 receptors -> ⬇ AV node conduction -> restoration of normal sinus rhythm in patients with PSVT

Also, (-) Ca and (+) adenylate cyclase in sm -> relaxation

Direct inhibition of beta- adrenergic receptors. Mediates (-) chronotropic effects involving K modulation, Ca and funny currents inhibition. Induction of preconditioning and ischemia tolerance in the heart.

Induce vasodilation (induction of nitric oxide).

Reduce neutrophil accumulation and inhibiting mast cell degranulation.

Inhibition of heart remodeling.

Inotropic effect (calcium release) and is able to counteract the anti-

adrenergic action of A1AR.

Inhibits cardiac fibroblast proliferation, as well as vascular smooth muscle cell growth and collagen synthesis.

Reduction in TGFβ-1 and angiotensin II- mediated collagen synthesis.

Modulation negatively the inflammatory respond in the smooth muscle cells.

Anti-inflammatory actions during reperfusion. Protect against postischemic neutrophil-mediated injury and may be involved in the regulation of bone marrow- derived cells.

Adverse effects: Bronchospasm, Transient asystole (lack of any cardiac rhythm whatsoever)

Heart rate lowering medicine for the symptomatic management of stable angina pectoralis and symptomatic chronic heart failure

Reduce the risk of hospitalization for worsening HF in adult patients with stable, symptomatic CHF with

LVEF ≤35%, who are in sinus rhythm with resting HR ≥70 beats per minute

Indicated for treatment of stable symptomatic HF

as a result of dilated cardiomyopathy for pediatric patients 6 months of age or more.

MAO: (-) If funny channels -> prolongs diastolic depolarization -> lowers pacemaker -> ⬇ HR in [] dependent ⬇ O2 demand

Adverse effects

i. Bradycardia, may cause fetal toxicity when administered to pregnant women.

ii. Effective contraception in women is recommended when using it.

NDD CCB, ketoconazole, St. Johns wort, Rifampicin and Phenytoin are contraindicated in:

For the management of chronic angina

Indications:

i. Chronic angina, Certain arrhythmias, including ventricular tachycardia.

ii. Acute coronary syndrome

MAO: (-) Na/K channels -> electrolyte imbalance

Adverse effects: dizziness, nausea, and vomiting. These effects have been shown to be dose related. High IV doses can cause diplopia, confusion, paresthesia, in addition to syncope. Prolongs the cardiac action potential duration and QT interval by 2 to 6 ms.

Dabigatarn, Rivaroxaban, Apixaban and Edoxaban are anticoagulants for: