Chapter 013. Chest Discomfort (Part 1)

Harrisons Internal Medicine Part 2. Cardinal Manifestations and Presentation of Diseases Section 1. Pain Chapter 13. Chest DiscomfortChest Discomfort: IntroductionChest discomfort is one of the most common challenges for clinicians in the office or emergency department. The differential diagnosis includes conditions affecting organs throughout the thorax and abdomen, with prognostic implications that vary from benign to life-threatening (Table 13-1).Failure to recognize potentially serious conditions such as acute ischemic heart disease, aortic dissection, tension pneumothorax, or pulmonary embolism can lead to serious complications, including death.Conversely, overly conservative management of low-risk patients leads to unnecessary hospital admissions, tests,...
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Chapter 013. Chest Discomfort (Part 1) Chapter 013. Chest Discomfort (Part 1) Harrisons Internal Medicine > Part 2. Cardinal Manifestations andPresentation of Diseases > Section 1. Pain > Chapter 13. Chest Discomfort Chest Discomfort: Introduction Chest discomfort is one of the most common challenges for clinicians in theoffice or emergency department. The differential diagnosis includes conditionsaffecting organs throughout the thorax and abdomen, with prognostic implicationsthat vary from benign to life-threatening (Table 13-1). Failure to recognize potentially serious conditions such as acute ischemicheart disease, aortic dissection, tension pneumothorax, or pulmonary embolismcan lead to serious complications, including death. Conversely, overly conservative management of low-risk patients leads tounnecessary hospital admissions, tests, procedures, and anxiety. Table 13-1 Differential Diagnoses of Patients Admitted to Hospital withAcute Chest Discomfort Ruled Not Myocardial Infarction Diagnosis Percent Gastroesophageal diseasea 42 Gastroesophageal reflux Esophageal motility disorders Peptic ulcer Gallstones Ischemic heart disease 31 Chest wall syndromes 28Pericarditis 4Pleuritis/pneumonia 2Pulmonary embolism 2Lung cancer 1.5Aortic aneurysm 1Aortic stenosis 1 Herpes zoster 1 a In order of frequency. Source: P Fruergaard et al: Eur Heart J 17:1028, 1996. Causes of Chest Discomfort Myocardial Ischemia and Injury Myocardial ischemia occurs when the oxygen supply to the heart is notsufficient to meet metabolic needs. This mismatch can result from a decrease inoxygen supply, a rise in demand, or both. The most common underlying cause of myocardial ischemia is obstructionof coronary arteries by atherosclerosis; in the presence of such obstruction,transient ischemic episodes are usually precipitated by an increase in oxygendemand as a result of physical exertion. However, ischemia can also result from psychological stress, fever, or largemeals or from compromised oxygen delivery due to anemia, hypoxia, orhypotension. Ventricular hypertrophy due to valvular heart disease, hypertrophiccardiomyopathy, or hypertension can predispose the myocardium to ischemiabecause of impaired penetration of blood flow from epicardial coronary arteries tothe endocardium.