Use Of Pharmacological Treatments For Heart Failure Essay Examples

The Role of Cardiovascular System

The cardiovascular system is responsible for the transport of oxygen and nutrients to the body. It is also responsible for carrying the waste that is to be eliminated by different organs (Shah et al. 2009, p. 11). This biological system is consisted of a series of tubes called the blood vessels that are connected to the heart which pumps blood. The arteries are the blood vessels that transport blood from the heart to the other parts of the body while the veins bring back the blood to the heart (Silverthorn 2007, p. 463-464). The heart is the main organ of the cardiovascular system. It beats at the rate of 50 bpm to 100 bpm (Noble et al. 2013). The normal human heart varies in size and weight. The average weight of the heart for males is 300 – 350 while it is 250 – 300 for females (Shah et al. 2009, p. 11). Oxygen is then transported to the body when the heart pumps the blood. Also, it distributes deoxygenated blood to the lungs. Oxygen can also be transported by combining it with hemoglobin molecules. Additionally, the heart has four chambers which left atrium, left ventricle, right atrium and right ventricle. In the right atrium, the blood which is poor in oxygen is returned to the right ventricle which pumps it to the lungs for re-oxygenation and removal of carbon dioxide. Meanwhile, the newly oxygenated blood coming from the lungs is delivered to the left atrium then it is passed through the left ventricle to be distributed to the different organs of the body (Guyton & Hall 2000). The heart is an important organ in a human body. However, there are many diseases associated with heart. These diseases may be caused by a person’s lifestyle or may be congenital.

The pathophysiology involved in heart failure

Heart failure may result from a person’s unhealthy lifestyle. For example, fatty tissues may build up in the walls of the arteries. Due to this problem, arteries might be clogged which will result to the deficiency of oxygenated blood in the heart (Lilly 2011). Another condition that may cause heart failure is the cardiac arrhythmia. In this condition, the heart beat irregularly that is, it can be too fast or too slow. Arrhythmia can be developed or acquired due to congenital heart problems. It can also be a result of problems with the electrical pathways in the heart. An example of electrical pathway problem is the Wolff-Parkinson-White syndrome wherein the electrical muscle tissue made rapid impulses which also fasten the heartbeat. When a heart beats above the average heartbeat, a person might be experiencing Tachycardia (Podrid & Kowey 2001). The most common type of this condition is the Right Ventricular outflow tract Tachycardia that is caused by the defect in the electrical node in the right ventricle. In this condition, the heart is not allowed to be filled with blood before beating (Huff 2006). To prevent having this heart problem, it is recommended to change one’s lifestyle or to undergo treatment. Wide choices of treatments are available to cure this heart disease.

Pharmacological treatments for heart diseases

There are different kinds of methods to treat cardiac arrhythmias. It is also important to monitor the patients having cardiac arrhythmia as this condition is episodic. There are many types of drugs available to treat this condition. Each kind has its own mode of action. Class III antiarrhythmic drugs blocs the sodium channels and acts like an anesthetic on cardiac cells. Quinidine, lidocaine, and procainamide are some examples of this drug. On the other hand, Class II antiarrhythmic drugs increases the refractory period of the Atrioventricular node. An example of this drug is propranolol. Meanwhile, the Class III antiarrhythmic drugs such as amiodarone and sotalol prolong the overall duration of the potential of cardiac action and increase the refractory method. Lastly, the Class IV antiarrhythmic drugs slow depolarization of pacemakers and block calcium channels. Verapamil and diltiazem are example of this type of drug (Zdanowicz 2002, pp. 127-128). One must carefully select the kind of treatment that will be used as every drug has its side effects. For emergency situations, the drug is introduced to the body intravenously. For regular treatment, these drugs can be taken by the patient orally. These drugs regulate the impulses of tissues that make the heart to beat rapidly. However, this treatment has two disadvantages which must be considered. These disadvantages are the risk of side effects and the indefinite and time taking this treatment. Most drugs have its side effects. However, the side effects caused by taking arrhythmic drugs are difficult to handle (American Heart Association [AHA] 2014). An example of antiarrhythmic drugs is Flecainide that has an effective sodium channel blockade effect. Flecainide increases the amount of electric current needed to capture the cardiac tissue. Using this drug, however, may also lead to blurred vision due to the dosage that the patient intakes. Another example is Amiodarone which is considered as the most effective drug for sinus-rhythm maintenance. It acts by blocking sodium channel while decreasing the calcium current. It also blocks potassium channels. One of the disadvantages of using amiodarone is it is poorly absorbed by the body making it difficult to be removed by the liver and the kidneys. It also gives side-effects such as corneal microdeposits, photosensitivity, hepatic dysfunction, hyperthyroidism, skin deposits, pulmonary fibrosis, and many other side-effects (Ganjehei, Massumi, Nazeri, & Razavi 2011). A patient has a wide range of medicines to choose from. One must analyze the possible effects of the drug that will be used to see what fits to the patient’s needs.

Recently discovered treatments

Other treatment that can be applied other than the use of medicines is by using electricity methods. This treatment is done by applying electrical shocks to the heart trough the chest or by implanting electrodes on the heart. One type of this treatment is the cardioversion wherein the electrical shock is applied synchronizing to the heartbeat. Patients undergoing this procedure are anesthetized. Another type is defibrillation wherein electrical shocks are also applied but they are not synchronized. In this treatment, more electricity is required and it also makes the patient unconscious (Tsiperfal 2011).

Levosimendan: A novel agent

There are several novel agents to treat heart failure. One of these agents is Levosimendan which is a calcium channel sensitizer. This agent improves left ventricle performance and prevents impairment of myofilament relaxation (Frishman & Sica 2011, p. 199) This agent is introduced to the body intravenously and is recommended for patients with acute congestive heart failure. Consequently, it can bring side effects due to the dosage and vasodilator effect (Lehtonen et al 1995). Side effects caused by taking this agent include headache, hypotension, nausea, and dizziness. Despite of these side-effects, studies show that this agent is safe to use. Also, it gives the positive result in preventing further heat failure (Moiseyev et al 2002). However, there are other guidelines that must be considered in using levosimendan. The European Society of Cardiology gives recommendation on how to use it with patients experiencing low-output heart failure (Nieminen et al 2005). Overall, this agent is most recommended because it is the safest agent to use to manage heart failure. It is also advice that should be consistently use and be part of the patient’s routine to prevent the worsening of the patient’s condition (O’Connor et al 2005, p. 492)

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