1. ANGINA PECTORIS
Brunner 2012
Chapter 28

2. ANGINA PECTORIS

3. Angina pectoris is a clinical syndrome usually characterized by episodes or paroxysms of pain or pressure in the anterior chest.
The cause is usually insufficient coronary blood flow.
In other words, the need for oxygen exceeds the supply.

5. Pathophysiology Angina is usually caused by atherosclerotic disease.
Several factors are associated with typical anginal pain:
1-Physical exertion, which can precipitate an attack by increasing myocardial oxygen demand
2-Exposure to cold, which can cause vasoconstriction and an elevated blood pressure, with increased oxygen demand.
3-Eating a heavy meal, which increases the blood flow to the mesenteric area for digestion, thereby reducing the blood supply available to the heart .
4-Stress or any emotion-causing the release of adrenaline and increasing blood pressure, which may accelerate the heart rate and increase the myocardial workload.

8. Types of Angina
Stable angina:predictable and consistent pain that occurs on exertion and is relieved by rest
Unstable angina (also called preinfarction angina or crescendo=increase angina): symptoms occur more frequently and last longer than stable angina. The threshold for pain is lower, and pain may occur at rest.
Intractable or refractory angina:severe incapacitating chest pain.

9. …Types of Angina
Variant angina (also called Prinzmetal’s angina): pain at rest with eversible ST-segment elevation; thought to be caused by coronary artery vasospasm.
Silent ischemia: objective evidence of ischemia (such as electrocardiographic changes with a stress test), but patient reports no symptoms.

11. Clinical Manifestations
Ischemia of the heart muscle may produce pain or other symptoms, varying in severity.
The pain is often (retrosternal area).
Typically, the pain or discomfort is poorly localized and may radiate to the neck, jaw, shoulders, and inner aspects of the upper arms, usually the left arm.

13. The patient often feels tightness or a heavy, choking, or strangling sensation that has a viselikeفشاری, insistent quality.
The patient with diabetes mellitus may not have severe pain with angina because the neuropathy .
A feeling of weakness or numbness in the arms, wrists, and hands may accompany the pain, as may shortness of breath,pallor, diaphoresis, dizziness or lightheadedness, and nausea and vomiting.

14. When these symptoms appear alone,they are called angina-like symptoms.
Anxiety may accompany angina.
An important characteristic of angina is that it abates or subsides with rest or nitroglycerin.

16. Gerontologic Considerations
The elderly person with angina may not exhibit the typical pain profile because of the diminished responses of neurotransmitters that occur in the aging process.
Often, the presenting symptom in the elderly is dyspnea.
If they do have pain, it is atypical pain that radiates to both arms rather than just the left arm.
Sometimes,there are no symptoms (“silent” CAD), making recognition and diagnosis a clinical challenge

17. Assessment and Diagnostic Findings
ECG
CAD is believed to result from inflammation of the arterial endothelium.
C-reactive protein (CRP) is a marker for inflammation of vascular endothelium.
High blood levels of CRP have been associated with increased coronary artery calcification and risk of an acute cardiovascular event (eg, MI) in seemingly healthy individuals .

18. An elevated blood level of homocysteine, an amino acid, has also been proposed as an independent risk factor for cardiovascular disease.
However, studies have not supported the relationship between mild to moderate elevations of homocysteine and atherosclerosis .
No study has yet shown that reducing homocysteine levels reduces the risk of CAD.

19. Medical Management
The objectives of the medical management of angina are to decrease the oxygen demand of the myocardium and to increase the oxygen supply.
percutaneous coronary interventional (PCI)procedures (eg, percutaneous transluminal coronary angioplasty [PTCA], intracoronary stents, and
atherectomy),
CABG,

20. PHARMACOLOGIC THERAPY
Among medications used to control angina are nitroglycerin,beta-adrenergic blocking agents, calcium channel blockers, and antiplatelet agents.

21. Nitroglycerin .
Nitroglycerin dilates primarily the veins and, in higher doses, also dilates the arteries.
Dilation of the veins causes venous pooling of blood throughout the body.
As a result, less blood returns to the heart, and filling pressure (preload) is reduced.
Nitrates in higher doses also relax the systemic arteriolar bed and lower blood pressure (decreased afterload).

22. Nitroglycerin may be given by several routes: sublingual tablet or spray, topical agent, and intravenous administration.
IV nitroglycerin usually is not given if the systolic blood pressure is 90 mm Hg or less.

23. 4

24. Beta-Adrenergic Blocking Agents
Beta-blockers such as propranolol (Inderal), metoprolol (Lopressor, Toprol), and atenolol (Tenormin) appear to reduce myocardial oxygen consumption by blocking the beta-adrenergic sympathetic stimulation to the heart.
reduced myocardial contractility.

25. The dose can be titrated to achieve a resting heart rate of 50 to 60 beats per minute.
Patients taking beta-blockers are cautioned not to stop taking them abruptly, because angina may worsen and MI may develop.

26. Calcium Channel Blocking Agents
increase myocardial oxygen supply by dilating the smooth muscle wall of the coronary arterioles; they decrease myocardial oxygen demand by reducing systemic arterial pressure and the workload of the left ventricle.
amlodipine (Norvasc), verapamil (Calan, Isoptin, Verelan), and diltiazem (Cardizem, Dilacor, Tiazac).
Amlodipine (Norvasc) and felodipine (Plendil) are the calcium channel blockers of choice for patients with heart failure.

27. Antiplatelet and Anticoagulant Medications
Antiplatelet medications are administered to prevent platelet aggregation, which impedes blood flow.

28. Aspirin
Aspirin prevents platelet activation and reduces the incidence of MI and death in patients with CAD.
A 160- to 325-mg dose of aspirin should be given to the patient with angina as soon as the diagnosis is made (eg, in the emergency room or physician’s office) and then continued with 81 to 325 mg daily.

29. Clopidogrel and Ticlopidine.
Clopidogrel (Plavix) or ticlopidine (Ticlid) is given to patients who are allergic to aspirin or given in addition to aspirin in patients at high risk for MI.
Unlike aspirin,these medications take a few days to achieve their antiplatelet effect.

30. Heparin
Heparin therapy is usually considered therapeutic when the aPTT is 1.5 to 2 times the normal aPTT value.
A subcutaneous injection of low-molecular-weight heparin(LMWH; enoxaparin [Lovenox] or dalteparin [Fragmin]) may be used.
the patient is monitored for signs and symptoms of external and internal bleeding.
Avoiding intramuscular injections.
A decrease in platelet count or skin lesions at heparin injection sites may indicate heparin-induced thrombocytopenia (HIT).

31. Oxygen Administration
Oxygen therapy is usually initiated at the onset of chest pain in an attempt to increase the amount of oxygen delivered to the myocardium and to decrease pain.