Cardiovascular Agents

Brief review of Cardiovascular System. Include in your paper drug class, subclass, generic/ brand name, drug indications, mechanism of action, standard guidelines in the United States, evidence-based practice recommendations, cardinal points of treatment (things to take into consideration when prescribing drug). Please include at minimum of two case studies. Remember to use information from reliable sources like peer reviewed articles and journals no older than five years, used in the United States. Do not forget to cite your sources on APA style

Cardiovascular Agents.

Cardiovascular system, also referred to as the circulatory system, consists of the heart and a closed system of blood vessels called arteries, veins and capillaries. The heart and blood vessels transports oxygen, nutrients and metabolic byproducts. The human heart has four distinct muscular chambers, that is; two atria and two ventricles which form separate left and right heart pumps that function differently. The left chamber of the heart has one atrium and one ventricle and its function is to pump blood from the pulmonary veins to the aorta. On the other hand, the function of the right chamber of the heart is to pump blood from the vena cava to the pulmonary arteries. It is composed of the right atrium and right ventricle.

The America heart association estimates that more than 50% of deaths are a result of cardiovascular diseases, and many of these are preventable. Many cardiovascular diseases such as hypertension (high blood pressure), angina (chest pain), stroke and coronary heart disease can be treated by variety of drugs as prescribed by healthcare providers. Most cardiovascular drugs that are commonly prescribed are broadly categorized into: anticoagulants, calcium channel blocking drugs, beta-receptor blocking drugs, vasodilators, cholesterol-lowering medication, diuretics, antiarrhythmic drugs and antiplatelet agents and dual antiplatelet therapy

Anticoagulants.

Anticoagulants are medically used to reduce the ability of blood to clot, to prevent clots from becoming larger which could lead to serious health problems and to prevent first or recurrent stroke. They are thus used to treat certain blood vessels, heart and lung conditions. The anticogulants that are commonly prescribed include: Apixaban (Eliquis), Dabigatran (Pradaxa), Edoxaban (Savaysa), Heparin (various), Rivaroxaban (Xarelto), Warfarin (Coumadin)

Heparin.

The anticoagulant action of heparin occurs through antithrombin which is an inhibitor of many proteases of the coagulation, especially thrombin and factor Xa, under physiological conditions. Therefore, it inhibits clothing by preventing conversion of fibrinogen to fibrin. Heparin is available in unfractionated form which acts by binding to antithrombin. This inactivates thrombin and factor Xa that shuts down the process of coagulation.

Warfarin.

This is an orally active anticoagulants which is a competitive inhibitor of vitamin K in biosynthesis of prothrombin. Warfarin antagonizes vitamin K- mediated final steps in the synthesis of clotting factors II,VII, IX and X in the liver and inhibits proteins C and S  synthesis that maintain anticoagulantion. Hypercoagulation may occur during the first 48 hours because Protein C falls early after the introduction of warfarin since it has a short half-life in the plasma. Therefore, in the first 48 hours heparin treatment should be used after administering warfarin until the inhibition of the procoagulant factors outweighs the effects on protein C.

Calcium channel blocking drugs.

These are prescribed to treat high blood pressure, angina that results from reduced blood supply to the heart vessels and some abnormal heart rhythms. Calcium channel blockers relaxes arteriolar smooth muscle, reduce peripheral vascular resistance and lower arterial blood pressure. They interrupt calcium movement into the heart cells and blood vessels and decreases the pumping strength of the heart and relax blood vessels. Calcium channel blockers that are commonly prescribed include: Amlodipine (Norvasc), Verapami (Calan, Verelan), Felodipine (Plendil), Nifedipine (Adalat, Procardia) and Nimodipine (Nimotop) among others.

Nifedipine

This is mainly used in the management of hypertension and angina in which the cardiac afterload needs to be reduced because it has greater action on vascular smooth muscles than on the heart. It leads bradycardia and reduction in cardiac output if overdosed but the effects can be reversed by substantial amount of calcium salts.

Verapamil.

Verapamil has its main place in the management of cardiac arrhythmias and angina than in the treatment of hypertension because it has greater selectivity for cardiac than on vascular calcium channel. If overdosed, it causes bradycardia and reduced heart output which is harmful and can lead to heart failure. These effects can however be reversed by use of massive calcium salts.

Beta-receptor blocking drugs.

        Beta-receptor blocking drugs are prescribed to help in reducing blood pressure, for cardiac arrhythmias, treating chest pain and prevention of future heart attack for patients who have had heart attack in the past. This medication works by decreasing the heart rate and contraction force making   the heart beat more slowly with less force due to reduced blood pressure. Some of the beta-receptor drugs prescribed include: Acebutolol (Sectral), Atenolol (Tenormin), Betaxolol (Kerlone), Bisoprolol/hydrochlorothiazide (Ziac), Bisoprolol (Zebeta), Metoprolol (Lopressor, Toprol XL) and Propranolol (Inderal).

Propranolol (Inderal)

         blocks both beta-1 and beta-2 receptors. It reduces heart rate, increased rate of contraction and excitability. It lowers blood pressure by reducing cardiac output and modulating peripheral. Its action in angina depends on the reduction of exercise-induced increases in cardiac work.

Atenolol (Tenormin)

        Atenolol is more selective for beta-1 receptors than propranolol. In high doses, this selectivity is lost. Atenolol has thesame action on the heart and blood pressure as propranolol but it is less likely to produce adverse effects on the peripheral vasculature, the bronchi and on the recovery from hypoglycaemia. Beta-blockers should not be recommended to patients who have history of asthma.

        In conclusion, cardiac medication comes in a many types and combinations which help in management of cardiac diseases by following the prescription given by a doctor. A patient should stick to the prescribed dose and should not stop taking the medication nor change medication without consultation with the doctor.