Porth's Essentials of Pathophysiology, 4e

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Disorders of Cardiac Function

C h a p t e r 1 9

demands of the myocardium. Stable angina is the initial manifestation of ischemic heart disease in approximately half of persons with CAD. 21,22 Although most persons with stable angina have atherosclerotic heart disease, angina is not a clinical manifestation in a considerable number of persons with advanced coronary atheroscle- rosis. Some persons may not report severe pain, perhaps because they are physically inactive, have collateral cir- culation, or do not feel pain due to neuropathy. Angina pectoris usually is precipitated by situations that increase the work demands of the heart, such as physical exertion, exposure to cold, and emotional stress. The pain is typically described as a steady con- stricting, squeezing, or a suffocating sensation, increas- ing in intensity only at the onset and end of the episode. This pain is commonly located in the precordial or sub- sternal area of the chest; it is similar to sensations associ- ated with myocardial infarction in that it may radiate to the left shoulder, jaw, arm, or other areas of the chest or back (Fig. 19-11). In some persons, the arm or shoulder pain may be confused with arthritis; in others, epigastric pain is confused with indigestion. Angina commonly is categorized according to whether it occurs with physi- cal activity, occurs during rest, is of new onset, or is of increasing severity. Typically, chronic stable angina is provoked by exer- tional activity or emotional stress and relieved within minutes by rest or by nitroglycerin. A delay of more than 5 to 10 minutes before relief is obtained suggests that the symptoms result from severe ischemia. Angina that occurs at rest, is of new onset, or is increasing in intensity or duration denotes an increased risk for myocardial infarction and should be evaluated using the criteria for ACS.

Left ventricle

Aneurysm

Right ventricle

FIGURE 19-10. Paradoxical movement of a left ventricular aneurysm during systole.

classifications: chronic stable angina, silent myocardial ischemia, and variant or vasospastic angina. Chronic Stable Angina Angina pectoris is a symptomatic paroxysmal chest pain or pressure sensation associated with transient myocar- dial ischemia. Chronic stable angina is associated with a fixed coronary obstruction that produces an imbal- ance between coronary blood flow and the metabolic

FIGURE 19-11. Areas of pain due to Angina including anterior and posterior views.