USE IN ISOSORBID DINITRAT Ischemic Heart Disease

A. Ischemic heart disease
Ischemic heart disease is the state of various etiologies, causing an imbalance between myocardial oxygen supply and demand. The most common cause of myocardial ischemia is atherosclerosis. The presence of atherosclerosis causes narrowing of the lumen of the coronary arteries so that epikardial myocardial oxygen supply is reduced. Myocardial ischemia can also occur because of increased myocardial oxygen demand is not normal as in ventricular hypertrophy or aortic stenosis. If transient ischemic events is associated with angina pectoris, if prolonged it can lead to myocardial necrosis and scar formation with or without clinical features of myocardial infarction (Isselbacher, 2000).

Drugs commonly used are antiangina (compound nitrates, beta blockers, calcium channel blockers) and asetosal (Isselbacher, 2000). Nitrate compounds work through two mechanisms. Nitrate compounds in vivo is a pro drug that becomes active after metabolized and produce nitrogen monoxide (NO). Biotransformation lasting intracellular nitrate compounds is influenced by the presence of extracellular reductase and reduced thiols (glutathione) intracellularly. Nitrogen monoxide will form complexes with guanilat nitrosoheme cyclase and stimulates this enzyme so that increased cGMP levels. Furthermore, cGMP will cause the dephosphorylation of myosin, resulting in smooth muscle relaxation. Mechanism of action of the latter is a result of nitrate compounds, the endothelium to release prostacyclin (PGI2) which are vasodilators. Based on these two mechanisms, nitrate compounds can cause vasodilation, and ultimately lead to decreased demand and increased supply of oxygen (Gunawan, 2007).

B. Therapeutic Targets

Epikardial coronary artery vasodilation.

C. Destination Therapy

Overcoming the pain of angina by balancing supply and myocardial oxygen demand.

D. Therapeutic Strategies

In acute attacks of angina are given a combination of two kinds antiangina (with the aim of increasing effectiveness and reducing side effects) and asetosal. If the angina attack does not improve on the provision of a combination of two kinds antiangina, it can be given a combination of three kinds antiangina. Antiangina used because it can decrease myocardial oxygen demand and increasing myocardial oxygen supply so that the balance between oxygen supply and demand is reached. Asetosal used because it can prevent or reduce platelet aggregation, thereby increasing blood flow is not obstructed (Isselbacher, 2000).

E. Medication Options

In this article, isosorbid dinitrat used as a drug of choice.

1. Generic Name: Isosorbid Dinitrat, sublingual tablets 5 mg, 10 mg

2. Trade name

Cedocard, tablets 5 mg, 10 mg, 20 mg
Cedocard Retard, 20 mg tablets LMB
Farsorbid, sub tablets 5 mg, 10 mg
Isoket, tablets 5 mg, 10 mg
Isoket Retard, LMB tablets 20 mg, 40 mg; fluid injection of 1 mg / ml; aerosol of 25 mg / ml; cream 100 mg / g
Isomack Retard, 20 mg capsules
Isomack Spray, buccal spray 13.9 mg / ml
TD Spray Iso Mack, transdermal spray 96.7 mg / ml
Vascardin, tablets 5 mg, 10 mg
3. Indications: Prophylaxis and treatment of angina; left heart failure

4. Contra-indications

Hypersensitivity to nitrates, hypotension and hypovolaemia, hypertrophic obstructive cardiopathy, aortic stenosis, cardiac tamponade, constrictive pericarditis, mitral stenosis, severe anemia, head trauma, brain hemorrhage, a narrow-angle glaucoma.

5. Dosage forms

Tablets, sublingual tablets, slow-release tablets, capsules, injectable liquids, aerosols, creams, buccal spray, and transdermal spray.

6. Dosage and Rules

Sublingual: 5-10 mg
Oral: daily in divided doses, angina 30-120 mg
Intravenous infusion: 2-10 mg / hour; a higher dose to 20 mg / day may be needed
7. Side effects

Throbbing headache, flushing, dizziness, postural hypotension, tachycardia (paradoxical bradycardia can occur). The typical side effects include severe hypotension after injection, nausea and vomiting, diaphoresis, worry, anxiety, muscle twitching, palpitations, abdominal pain, syncope, long-term administration is accompanied by methemoglobinemia.

8. Warning

Severe liver or kidney disorders; hypothyroidism, malnutrition, or hypothermia; myocardial infarction is still new; metal-containing transdermal system should be taken prior to cardioversion or diathermy.
Compounds or transdermal long-acting nitrates can lead to tolerance (reduced therapeutic effect). If tolerance is expected after use of transdermal preparations, such preparations must be removed for several consecutive hours in any 24 hour period.