Introduction
Angina refers to pain or tightness experienced in the chest area (Jevon, 2012). Angina is divided into stable and unstable angina. Stable angina takes place on exertion and occurs when the heart muscle demand for blood is more than the supply. On the other hand, unstable angina may occur in variety of clinical situations. This may include patients having coronary artery disease. Patients having unstable angina usually undergo diagnostic and therapeutic procedures that are used on other coronary artery diseases patients (Braunwald, 1997).
Unstable angina emanates from the increase in myocardial oxygen demand or in a reduction in myocardial oxygen supply. Reduction is supply of the myocardial oxygen may be caused by anemia, spasm of the epicardial coronary artery or development of a platelet-rich thrombus on a fissured plaque (Braunwald, 1997). When a plaque ruptures, blood clots form. The blood clots formed can grow in size. Blood clots partially or completely block arteries causing the development of angina. Patients having unstable angina have lesions that are more complex and more coronary thrombus on coronary arteriograms than patients with stable angina.
Risk factors associated with angina include presence of diabetes, obesity, high blood pressure, high or unhealthy cholesterol levels, heart disease, tobacco smoking, inactive lifestyle, old age and having a metabolic syndrome.
Characteristics of Anginal Pain
Angina pain is characterized by burning sensation and is poorly localized. According to Friedman (2001), the pain is of moderate intensity and can last between two and ten minutes. The pain has a high chance of occurrence after meals, stress activities such as running or walking up and down a staircase or exposure to wind or cold.
Symptoms
A common symptom associated with angina is dyspnea. According to Lanzer and Topol (2002), a patient may be unable to take deep breaths. The patient will complain of discomfort in the retrosternal area (Griffin et al., 2012). According to Lanzer and Topol (2002), patients’ indication of pain over the sternum with a fist gives an indication of angina. Angina pain usually may vary in location. The pain can occur between the shoulder blades, upper chest area, lower part of the neck, epigastrium or in the interscapular area (Lanzer and Topol, 2002). Angina can occur with or without radiation. In cases where patients have a difficult time describing the character of radiation, occurrence of angina is highly likely. Angina pain may begin in the arm and radiate to the chest, epigastrium, the back, armpits, and the interscapluar areas. Symptoms that are established through physical examination may include an elevated blood pressure, signs of hyperlipidemic conditions or vascular disease.
Diagnosis of Angina
Diagnosis of angina requires an examination of the patient’s clinical history, physical examination and examination of a resting 12-lead ECG (Braunwald, 1994). The physical examination may provide evidence for the diagnosis of angina. Findings of the physical examination that support this include an audible or palpable fourth heart sound, rise in blood pressure or pulse rate, paradoxical splitting of the second heart sound, a palpable dyskinetic area or bulge at or around the cardiac apex and appearance of the murmur of mitral regurgitation due to papillary muscle dysfunction (Friedman, 2001).
Diagnosis can also be done using nitroglycerin. Using the sublingual nitroglycerin will relieve angina pain within three minutes or less in most of the cases. However, this will require the tablets to have the ability to induce headache and produce a burning sensation under the tongue. If the nitroglycerin does not relieve pain in the three minutes duration, then it is an indication that the pain is not angina (Friedman, 2001).
Diagnosis can also be carried out using electrocardiographic changes. Absence of electrocardiographic changes is a characteristic sign for angina pectoris (Friedman, 2001). Angina attacks have a characteristic S-T segment depression, which is caused by ischemia and sub-endocardia injury (Friedman, 2001). Exercise testing (walking up and down a flight of stair or riding a stationary bicycle) increases the accuracy of the electrocardiographic diagnosis when an ECG is recorded during the exercise and after the exercise. One mm of flat or down sloping S-T segment that lasts between 0.08-0.12 seconds indicates a positive diagnosis for angina. It is recommended to use radionuclide scanning with addition of Thallium-201 or Technetium-99m to improve the accuracy of the exercise. This is normally done when the exercise ECG becomes difficult to interpret.
Selective coronary angiography can also be used to diagnose angina. This will be the case when the angiography does not record any presence of arterial narrowing. This gives an indication of the absence of angina (Friedman, 2001). Blood tests are also used in the diagnosis of angina where levels of sugars, fats, and proteins are analyzed
During diagnosis, the angina can be classified into three classes. According to Sami and Willerson (2010), rest angina occurs when the patient is at rest and can last for duration longer than 20 minutes. The second class is the new-onset angina, which occurs, has occurred within the past two months. If the angina has become more frequent, and has longer durations it is referred to as increasing angina (Sami and Willerson, 2010).
EKG/Healthcare technician’s role
The healthcare technician is responsible for preparing the patient to take the test. The technician will place electrodes on the chest of the patient, which are then connected to an EKG monitor, which follows the electrical activity of the heart while the patient exercises. The technician is responsible for explaining the procedure to the patient and answers any concerns that the patient may have. The technician has a duty to inform the patient in case he or she may be required to shave the area where the electrodes will be placed.
Reassuring the patient is necessary as this may help reduce any anxiousness that the patient may have while taking the test. During the test, the technician has to ensure that the patient’s body is not in contact with any metal surface. This will ensure that tracing is not distorted. After completing the EKG, the technician has to document the procedure and provide the nurse or doctor with the EKG tracing. The technician ensures that leads used are placed in the correct positions as wrong placing can give false readings. Additionally, the leads used need to be placed in areas with least amount of fat tissue. Furthermore, the technician checks the electrodes used to ensure they have sufficient gel to maintain contact with the placement area on the body of the patient.
Role of EKG Monitoring
EKG monitoring provides a non-invasive method of testing for angina (Bouzas-Mosquera, Peteiro, Broullón, Méndez, Barge-Caballero, López-Pérez, and Castro-Beiras, 2012). The EKG test or the exercise test is one of the most common methods used to diagnose angina and has been reported to be very useful in most patients that have been diagnosed with angina (Braunwald, 1994). The test has a nomogram, which has been developed from a large sample of patients that have experienced coronary arterial disease. The application of the nomogram assists in providing more quantitative results rather than a normal or abnormal reading. Through the stress testing, it can be established if there is abnormal changes in the pulse rate, chest pains and abnormal changes in the heart rhythm all of which are significant pointers to the presence of angina.
Medical Management of Angina
Drug therapy is recommended as an initial treatment to angina. This is done after the initial evaluation of the presence of angina. The most common drugs used at this stage are aspirin, heparin, nitrates, and beta-blockers. This drug therapy needs to be started immediately after the diagnosis. Drug dosage will be provided depending on the severity of the angina (Braunwald, 1994). Beta-blockers used include propranolol, atenolol, and metoprolol, which help in reducing the incidence of acute myocardial infarction in patients with unstable angina, reducing myocardial oxygen demand by decreasing heart rate (Galvagno, 2013). Nitrates are significant in pain reduction.
In cases where the patients have low risk angina, outpatient care is recommended to monitor any adverse outcomes. A follow-up needs to be done 72 hours after the initial evaluation. An EKG and blood pressure levels are done. The patient is then advised to take aspirin. In cases where the patient is not able to take aspirin, clopidogel can be used (Griffin et al., 2012).Therapy can also be done using sublingual nitroglycerin, which is then followed by the taking oral beta-blockers or oral nitrates.
Lifestyle modification can also be applied to as a medical management approach. According to Griffin et al., (2012), individuals are encouraged to exercise skeletal muscles. The exercise training is significant in lowering heart rate for any level of exertion. Additionally, individuals need to observe their diet keenly. Recommended diet should be low in fat. Cereals and vegetables are highly recommended. This diets help reduce cardiovascular risk. Individuals who smoke are at higher risk of suffering angina. Cigarette smoking results to increase in myocardial demand since it causes an increase in alpha-adrenergic in the coronary tone (Griffin et al., 2012). People suffering from angina are advised to exercise calm and avoid situation where they can get angry or hostile, as this may be detrimental to the prevention of angina.
Treatment can also be done using enhanced external counterpulsation. This treatment involves the recurrent compression of the lower extremities in an effort to increase diastolic pressure and augment coronary blood flow (Griffin et al., 2012). It involves using three set of balloons, which are draped around the lower legs, lower thighs and the upper thighs, with precise cuff inflation and deflation with the EKG (Griffin et al., 2012). Clinical trials on patients with refractory angina shows improvements in exercise tolerance, decreased use of nitroglycerin and a reduction in angina symptoms (Griffin et al., 2012).
Future Medical Therapies
Pharmacology therapy options are also available. According to Griffin (2012), therapy can be via direct infusion of a vascular endothelial growth factor (VEGF) and basic fibroblast growth factor protein, which help improve blood flow.
References
Bouzas-Mosquera, A., Peteiro, J., Broullón, F. J., Méndez, E., Barge-Caballero, G., López-Pérez, M., & Castro-Beiras, A. (2012). Impact of electrocardiographic interpretability on outcome in patients referred for stress testing. European Journal of Clinical Investigation, 42(5), 541-547.
Braunwald, E., (1994). Diagnosing and managing unstable angina. Agency for Health Care Policy and Research. Journal of the American Heart Association, 90(1), 613-622.
Braunwald, E. (1997). Unstable Angina: Diagnosis and Management - Clinical Practice Guideline: DIANE
Friedman, H. H. (2000). Problem-oriented medical diagnosis. Lippincott Williams & Wilkins.
Galvagno, S. M. (2003). Emergency pathophysiology: Clinical applications for prehospital care: Samuel M. Galvagno Jr. Jackson, Wyo: Teton NewMedia.
Griffin, B. P., Callahan, T. D., Menon, V., Wu, W. M., Cauthen, C. A., Dunn, J. M., & Ovid Technologies, Inc. (2013). Manual of cardiovascular medicine. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins.
Jevon, P. (2012). Angina and heart attack. Oxford: Oxford University Press.
Lanzer, P. (2002). Panvascular medicine: Integrated clinical management; with 291 tables. Berlin: Springer.
Sami, S., & Willerson, J. T. (2010). Contemporary Treatment of Unstable Angina and Non-ST-Segment-Elevation Myocardial Infarction (Part 1). Texas Heart Institute Journal, 37(2), 141-148.
