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Chest Pain
CHAPTER
29
Chest Pain:
Differential Diagnosis
T
wo major clinical syndromes presenting as chest pain are angina pectoris and myocardial infarction (MI). Yet on occasion chest pain may not be cardiac in origin. Indeed, everybody experiences various forms of chest pain occasionally. Fortunately, most of these pains are unrelated to ischemic heart disease and are, for the most part, innocuous or, at the least, not acutely life threatening. However, many persons experiencing any pain in their chest have stopped and thought, “This pain I am feeling now is the real thing.” This chapter describes the differences between chest pain associated with ischemic heart disease and that which is not likely cardiac in origin.1 Following that the differential diagnosis of the two major forms of cardiac (ischemic) chest pain, angina pectoris and acute myocardial infarction, is presented. Box 29-1 lists some of the many possible causes of chest pain.
Noncardiac Chest Pain Noncardiac chest pain may usually be differentiated from the ischemia-induced pain of angina and myocardial infarction because the sharp, knifelike chest pain that increases in intensity with inspiration and diminishes with exhalation is usually not related to cardiac syndromes. Chest pain aggravated by movement (e.g., twisting, turning, or stretching of the sore area) is most often related to muscle or nerve injuries, not cardiac disease. I use the word usually when describing “typical” chest pains because there are instances in which patients are aware of sharp, knifelike pains that may in fact be related to cardiac disease. Variations from the typical presentation are expected, and the dental health professional is well advised to take note of this. Probably the most common cause of noncardiac chest pain is musculoskeletal, resulting from muscle strain that occurs after exercise or physical exertion.2 This form of pain is normally localized (the patient can point
to a specific site of discomfort), does not radiate, and is made worse by breathing and movement. A heating pad or mild analgesic medication may give relief. Pericarditis is an inflammation of the outer membrane covering the heart (the pericardium) and most commonly results from viral infection. The pain of pericarditis is similar to that of angina or myocardial infarction, occurs in the midsternum, and is described as “oppressive.” Clues to its differential diagnosis include aggravation of the pain of pericarditis when breathing and swallowing, characteristic relief of the pain when the patient bends forward from the waist, and often the presence of a fever before the onset of pain.3 Esophagitis, with or without hiatal hernia, produces a substernal or epigastric burning pain precipitated by eating or lying down after a meal. The pain is relieved by antacids. There often is an acid reflux into the mouth.4 Pulmonary embolism usually indicates the sudden occlusion of a blood vessel within the lungs by an embolus that has been “thrown” (broken loose) from the legs. The patient experiences a sudden severe chest pain that is commonly associated with the coughing up of blood-tinged sputum.5 Pulmonary embolism represents an acutely life-threatening situation. A less common cause of acute chest pain is dissecting aortic aneurysm. The patient experiences sudden, acute, severe chest pain that is often greatest at onset. Typically, it spreads up and down the chest and back over a period of hours. The dissecting aortic aneurysm may lead rapidly to death.6 Two other common causes of chest pain often make it difficult to differentiate between cardiac and noncardiac pain. These are the pains of acute indigestion and “gas,” occurring primarily in the upper epigastric region. A major factor responsible for the high initial mortality rate associated with MI is misinterpretation or denial of clinical symptoms by the patient or their attending physician.
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476
PART 7 CHEST PAIN
BOX 29-1
Causes of chest pain
CARDIAC RELATED Angina pectoris Myocardial infarction
NOT CARDIAC RELATED Muscle strain (musculoskeletal) Pericarditis Esophagitis Hiatal hernia Pulmonary embolism Dissecting aortic aneurysm Acute indigestion Intestinal “gas”
Symptoms commonly attributed to indigestion or gas are only later discovered to have been produced by MI. Gas pain is normally sharp and knifelike, increasing in intensity with breathing. This fact should help differentiate gas pain from the pain of ischemic heart disease. Acute indigestion is similar to the pain of angina or myocardial infarction; therefore, all patients with this symptom should be carefully evaluated. Epigastric discomfort can be a manifestation of myocardial ischemia or infarction and must not be dismissed lightly. Unusual or prolonged indigestion should rouse suspicion, particularly in a high-risk individual. The American Heart Association recommends that a patient with previously unrecognized CAD seek medical assistance if suspicious chest pain persists for 2 minutes or longer.7
Cardiac Chest Pain Angina and MI are the two most common causes of ischemic heart disease–related chest pain in the dental environment. Differential diagnosis is essential because these two syndromes represent quite different risks to the patient and are ultimately managed differently. The following discussion is offered to assist in making this differential diagnosis.
Medical history The patient with angina is aware of its existence and carries drugs (e.g., nitroglycerin) to manage acute anginal episodes. It is possible that a patient with a negative history of heart problems will suffer a first episode of angina in the dental office setting. Because of the stress associated with many dental procedures, at least in the minds of dental patients, there is frequently an increase in myocardial workload in the dental office setting. It is not unlikely that episodes of anginal-type chest pain may develop in this situation, especially in patients with a history of angina. However, absent a history of chest pain, the possibility also exists that this first
e pisode of chest pain might be an MI. For this reason, it is strongly recommended that a first episode of chest pain be managed as though it were an MI, until proven otherwise. The patient’s medical history may indicate a prior MI. Many patients who survive MI later develop episodes of angina and will have nitroglycerin available. In the absence of an existing history of angina pectoris, always assume that a first episode of chest pain is MI and activate emergency medical service (EMS) immediately!
Age Coronary artery disease (CAD) can be found in all age groups. There is little clinical difference between the age of patients developing angina and those sustaining an MI. Clinical evidence of CAD is most commonly observed between the ages of 50 and 60 years in men and 60 and 70 years in women.
Sex CAD is primarily a disease of males. The overall male: female ratio is 4:1. Before the age of 40 years, the ratio is 8:1.
Related circumstances The clinical symptoms of angina are usually associated with some form of exertion, whether physical or emotional. On the other hand, although MI may occur during or immediately after a period of exertion, it frequently occurs during periods of rest. Angina rarely occurs during rest, although coronary artery spasm may provoke anginal pain at any time. Unstable angina, by definition, may occur at rest. When chest pain develops at rest in the dental environment, activation of EMS should be seriously considered.
Clinical symptoms and signs Location of chest pain Location of chest pain is not a reliable indicator of the nature of the pain. Both anginal pain and the pain of MI occur substernally or just to the left of the midsternal region.
Description of chest pain Chest “pain” associated with angina or MI is usually not described as pain by the patient. Commonly the sensation is described as “squeezing,” “pressing,” “tightness,” “heaviness,” “as though there were a heavy weight on my chest,” or “crushing.” The pain associated with MI is more intense than that of angina and is more commonly described as painful or intolerable.
Radiation of chest pain Differentiation between angina and MI is difficult to make by using radiation of pain as a criterion because
chapter 29 CHEST PAIN: DIFFERENTIAL DIAGNOSIS
both have similar radiation patterns. Radiation of pain commonly occurs in the left shoulder and medial aspect of the left arm, following the distribution of the ulnar nerve. Less frequently pain may radiate to the right shoulder, the mandibular region, or the epigastrium.
Duration of chest pain The pain associated with MI is normally of long duration, lasting from 30 minutes to several hours if untreated. As discussed in Chapter 28, untreated cardiac pain may induce cardiogenic shock. Pain associated with angina is almost always brief. The administration of nitroglycerin or merely terminating the activity that induced the episode brings relief within 2 to 4 minutes. Anginal episodes precipitated by eating a large meal or anger may persist longer, lasting perhaps 30 minutes or more.
Response to medication Probably the most reliable diagnostic tool is the patient’s response to the administration of medications. A vasodilator, usually nitroglycerin, is administered. Anginal pain will be relieved approximately 2 to 4 minutes after administration of nitroglycerin. Nitroglycerin may temporarily diminish the pain of myocardial infarction, but more commonly has no effect. The pain of MI is commonly managed through administration of opioid analgesics, such as morphine, or nitrous oxide and oxygen. Administration of a vasodilator to the patient with presumed cardiac-related chest pain offers a fairly reliable method of differentiating between the pain of angina and MI. For this reason, the administration of one dose of nitroglycerin is one of the initial steps in the clinical drug management (along with O2) of chest pain in the dental office, assuming no contraindications to its administration are present (e.g., systolic BP <90 mm Hg or recent [<24 hours] ingestion of an erectile dysfunction drug).
Vital signs
usual. During MI, clinical evidence of left ventricular failure leading to respiratory distress may be noted.
Other signs and symptoms Most patients with MI and some patients with angina appear quite apprehensive, bathed in cold sweat. Anginal patients can compare the present episode with previous ones, which can give a clue as to the nature of the present attack. Anginal episodes tend to be similar in an individual patient. Changes in severity, duration, or frequency may indicate the occurrence of unstable angina or MI. Patients with MI often express a fear of impending doom. During MI, facial skin may appear ashen gray. Nail beds and other visible mucous membranes may appear cyanotic. These changes rarely occur during episodes of angina. Nausea and vomiting are common during MI, especially in the presence of severe pain. Nausea and vomiting are uncommon with anginal pain.
Summary The clinical diagnosis of chest pain is difficult. However, the response of the patient to the administration of one oral dose of nitroglycerin frequently leads to an accurate diagnosis. Acute anginal episodes are usually similar from episode to episode for a given patient. Any change in the nature of acute angina producing a more severe episode may indicate the occurrence of MI. Noncardiac chest pain usually is easy to differentiate from ischemic heart pain because of the nature of the pain. However, two common forms of substernal upper epigastric discomfort—acute indigestion and gas—may prove difficult to differentiate from ischemic heart pain. These symptoms cannot be ignored. Careful evaluation is required and medical consultation, or EMS activation, considered if there is any doubt as to the cause of a patient’s chest pain. Table 29-1 differentiates cardiac from noncardiac pain.
Heart rate Heart rate during acute episodes of angina increases and may feel full or bounding. A rapid heart rate may also occur during MI; however, because blood pressure is usually decreased, the pulse may feel weak or thready. The heart rate during MI may also be slow (bradycardia).
TABLE 29-1 Comparison of cardiac and
noncardiac pain
Noncardiac chest pain
Cardiac chest pain
Sharp, knifelike
Dull
Blood pressure
Stabbing sensation
Aching
Episodes of angina are normally accompanied by marked elevations in blood pressure, whereas blood pressure in MI may be normal but more commonly is decreased.
Aggravated by movement
Heaviness, oppressive feeling
Present only with breathing
Present at all times
Localized (patient able to point to one spot)
Generalized (occurs over a wider area)
Respiration Patients with either acute coronary syndrome may exhibit respiratory distress. Respiratory rate is increased while the depth of respiration may be more shallow than
Data obtained from Malamed SF: Beyond the basics: emergency medicine in dentistry, J Am Dent Assoc 128:843–854, 1997.
477
478
PART 7 CHEST PAIN
REFERENCES 1. Malamed SF: Beyond the basics: emergency medicine in dentistry, J Am Dent Assoc 128:843–854, 1997. 2. Kurz MC, Mattu A, Brady WJ: Acute coronary syndrome. In: Marx JA, Hockberger RS, Walls RM, editors: Rosen’s emergency medicine: concepts and clinical practice, ed 5, Elsevier Saunders, Philadelphia, 2014, pp. 997–1033. 3. Fallon EM, Roques J: Acute chest pain, AACN Clin Issues 8:383–397, 1997. 4. Lemire S: Assessment of clinical severity and investigation of uncomplicated gastroesophageal reflux disease and
noncardiac angina-like chest pain, Can J Gastroenterol 11:37B–40B, 1997. 5. Favretto G, Stritoni P: Pulmonary embolism: diagnostic algorithms, Ital Heart J 6:799–804, 2005. 6. Cayley ME: Chest pain, In: Bope ET, Kellerman RD e ditors: Conn’s current therapy, Elsevier Saunders, Philadelphia, 2014. 7. Heart attack, stroke & cardiac arrest warning signs, Dallas, American Heart Association, 2014. http://www.heart.org/ HEARTORG/General/Heart-Attack-Stroke-and-CardiacArrest-Warning-Signs. Accessed February 7, 2014.
29
Chest Pain:
Differential Diagnosis
T
wo major clinical syndromes presenting as chest pain are angina pectoris and myocardial infarction (MI). Yet on occasion chest pain may not be cardiac in origin. Indeed, everybody experiences various forms of chest pain occasionally. Fortunately, most of these pains are unrelated to ischemic heart disease and are, for the most part, innocuous or, at the least, not acutely life threatening. However, many persons experiencing any pain in their chest have stopped and thought, “This pain I am feeling now is the real thing.” This chapter describes the differences between chest pain associated with ischemic heart disease and that which is not likely cardiac in origin.1 Following that the differential diagnosis of the two major forms of cardiac (ischemic) chest pain, angina pectoris and acute myocardial infarction, is presented. Box 29-1 lists some of the many possible causes of chest pain.
Noncardiac Chest Pain Noncardiac chest pain may usually be differentiated from the ischemia-induced pain of angina and myocardial infarction because the sharp, knifelike chest pain that increases in intensity with inspiration and diminishes with exhalation is usually not related to cardiac syndromes. Chest pain aggravated by movement (e.g., twisting, turning, or stretching of the sore area) is most often related to muscle or nerve injuries, not cardiac disease. I use the word usually when describing “typical” chest pains because there are instances in which patients are aware of sharp, knifelike pains that may in fact be related to cardiac disease. Variations from the typical presentation are expected, and the dental health professional is well advised to take note of this. Probably the most common cause of noncardiac chest pain is musculoskeletal, resulting from muscle strain that occurs after exercise or physical exertion.2 This form of pain is normally localized (the patient can point
to a specific site of discomfort), does not radiate, and is made worse by breathing and movement. A heating pad or mild analgesic medication may give relief. Pericarditis is an inflammation of the outer membrane covering the heart (the pericardium) and most commonly results from viral infection. The pain of pericarditis is similar to that of angina or myocardial infarction, occurs in the midsternum, and is described as “oppressive.” Clues to its differential diagnosis include aggravation of the pain of pericarditis when breathing and swallowing, characteristic relief of the pain when the patient bends forward from the waist, and often the presence of a fever before the onset of pain.3 Esophagitis, with or without hiatal hernia, produces a substernal or epigastric burning pain precipitated by eating or lying down after a meal. The pain is relieved by antacids. There often is an acid reflux into the mouth.4 Pulmonary embolism usually indicates the sudden occlusion of a blood vessel within the lungs by an embolus that has been “thrown” (broken loose) from the legs. The patient experiences a sudden severe chest pain that is commonly associated with the coughing up of blood-tinged sputum.5 Pulmonary embolism represents an acutely life-threatening situation. A less common cause of acute chest pain is dissecting aortic aneurysm. The patient experiences sudden, acute, severe chest pain that is often greatest at onset. Typically, it spreads up and down the chest and back over a period of hours. The dissecting aortic aneurysm may lead rapidly to death.6 Two other common causes of chest pain often make it difficult to differentiate between cardiac and noncardiac pain. These are the pains of acute indigestion and “gas,” occurring primarily in the upper epigastric region. A major factor responsible for the high initial mortality rate associated with MI is misinterpretation or denial of clinical symptoms by the patient or their attending physician.
475
476
PART 7 CHEST PAIN
BOX 29-1
Causes of chest pain
CARDIAC RELATED Angina pectoris Myocardial infarction
NOT CARDIAC RELATED Muscle strain (musculoskeletal) Pericarditis Esophagitis Hiatal hernia Pulmonary embolism Dissecting aortic aneurysm Acute indigestion Intestinal “gas”
Symptoms commonly attributed to indigestion or gas are only later discovered to have been produced by MI. Gas pain is normally sharp and knifelike, increasing in intensity with breathing. This fact should help differentiate gas pain from the pain of ischemic heart disease. Acute indigestion is similar to the pain of angina or myocardial infarction; therefore, all patients with this symptom should be carefully evaluated. Epigastric discomfort can be a manifestation of myocardial ischemia or infarction and must not be dismissed lightly. Unusual or prolonged indigestion should rouse suspicion, particularly in a high-risk individual. The American Heart Association recommends that a patient with previously unrecognized CAD seek medical assistance if suspicious chest pain persists for 2 minutes or longer.7
Cardiac Chest Pain Angina and MI are the two most common causes of ischemic heart disease–related chest pain in the dental environment. Differential diagnosis is essential because these two syndromes represent quite different risks to the patient and are ultimately managed differently. The following discussion is offered to assist in making this differential diagnosis.
Medical history The patient with angina is aware of its existence and carries drugs (e.g., nitroglycerin) to manage acute anginal episodes. It is possible that a patient with a negative history of heart problems will suffer a first episode of angina in the dental office setting. Because of the stress associated with many dental procedures, at least in the minds of dental patients, there is frequently an increase in myocardial workload in the dental office setting. It is not unlikely that episodes of anginal-type chest pain may develop in this situation, especially in patients with a history of angina. However, absent a history of chest pain, the possibility also exists that this first
e pisode of chest pain might be an MI. For this reason, it is strongly recommended that a first episode of chest pain be managed as though it were an MI, until proven otherwise. The patient’s medical history may indicate a prior MI. Many patients who survive MI later develop episodes of angina and will have nitroglycerin available. In the absence of an existing history of angina pectoris, always assume that a first episode of chest pain is MI and activate emergency medical service (EMS) immediately!
Age Coronary artery disease (CAD) can be found in all age groups. There is little clinical difference between the age of patients developing angina and those sustaining an MI. Clinical evidence of CAD is most commonly observed between the ages of 50 and 60 years in men and 60 and 70 years in women.
Sex CAD is primarily a disease of males. The overall male: female ratio is 4:1. Before the age of 40 years, the ratio is 8:1.
Related circumstances The clinical symptoms of angina are usually associated with some form of exertion, whether physical or emotional. On the other hand, although MI may occur during or immediately after a period of exertion, it frequently occurs during periods of rest. Angina rarely occurs during rest, although coronary artery spasm may provoke anginal pain at any time. Unstable angina, by definition, may occur at rest. When chest pain develops at rest in the dental environment, activation of EMS should be seriously considered.
Clinical symptoms and signs Location of chest pain Location of chest pain is not a reliable indicator of the nature of the pain. Both anginal pain and the pain of MI occur substernally or just to the left of the midsternal region.
Description of chest pain Chest “pain” associated with angina or MI is usually not described as pain by the patient. Commonly the sensation is described as “squeezing,” “pressing,” “tightness,” “heaviness,” “as though there were a heavy weight on my chest,” or “crushing.” The pain associated with MI is more intense than that of angina and is more commonly described as painful or intolerable.
Radiation of chest pain Differentiation between angina and MI is difficult to make by using radiation of pain as a criterion because
chapter 29 CHEST PAIN: DIFFERENTIAL DIAGNOSIS
both have similar radiation patterns. Radiation of pain commonly occurs in the left shoulder and medial aspect of the left arm, following the distribution of the ulnar nerve. Less frequently pain may radiate to the right shoulder, the mandibular region, or the epigastrium.
Duration of chest pain The pain associated with MI is normally of long duration, lasting from 30 minutes to several hours if untreated. As discussed in Chapter 28, untreated cardiac pain may induce cardiogenic shock. Pain associated with angina is almost always brief. The administration of nitroglycerin or merely terminating the activity that induced the episode brings relief within 2 to 4 minutes. Anginal episodes precipitated by eating a large meal or anger may persist longer, lasting perhaps 30 minutes or more.
Response to medication Probably the most reliable diagnostic tool is the patient’s response to the administration of medications. A vasodilator, usually nitroglycerin, is administered. Anginal pain will be relieved approximately 2 to 4 minutes after administration of nitroglycerin. Nitroglycerin may temporarily diminish the pain of myocardial infarction, but more commonly has no effect. The pain of MI is commonly managed through administration of opioid analgesics, such as morphine, or nitrous oxide and oxygen. Administration of a vasodilator to the patient with presumed cardiac-related chest pain offers a fairly reliable method of differentiating between the pain of angina and MI. For this reason, the administration of one dose of nitroglycerin is one of the initial steps in the clinical drug management (along with O2) of chest pain in the dental office, assuming no contraindications to its administration are present (e.g., systolic BP <90 mm Hg or recent [<24 hours] ingestion of an erectile dysfunction drug).
Vital signs
usual. During MI, clinical evidence of left ventricular failure leading to respiratory distress may be noted.
Other signs and symptoms Most patients with MI and some patients with angina appear quite apprehensive, bathed in cold sweat. Anginal patients can compare the present episode with previous ones, which can give a clue as to the nature of the present attack. Anginal episodes tend to be similar in an individual patient. Changes in severity, duration, or frequency may indicate the occurrence of unstable angina or MI. Patients with MI often express a fear of impending doom. During MI, facial skin may appear ashen gray. Nail beds and other visible mucous membranes may appear cyanotic. These changes rarely occur during episodes of angina. Nausea and vomiting are common during MI, especially in the presence of severe pain. Nausea and vomiting are uncommon with anginal pain.
Summary The clinical diagnosis of chest pain is difficult. However, the response of the patient to the administration of one oral dose of nitroglycerin frequently leads to an accurate diagnosis. Acute anginal episodes are usually similar from episode to episode for a given patient. Any change in the nature of acute angina producing a more severe episode may indicate the occurrence of MI. Noncardiac chest pain usually is easy to differentiate from ischemic heart pain because of the nature of the pain. However, two common forms of substernal upper epigastric discomfort—acute indigestion and gas—may prove difficult to differentiate from ischemic heart pain. These symptoms cannot be ignored. Careful evaluation is required and medical consultation, or EMS activation, considered if there is any doubt as to the cause of a patient’s chest pain. Table 29-1 differentiates cardiac from noncardiac pain.
Heart rate Heart rate during acute episodes of angina increases and may feel full or bounding. A rapid heart rate may also occur during MI; however, because blood pressure is usually decreased, the pulse may feel weak or thready. The heart rate during MI may also be slow (bradycardia).
TABLE 29-1 Comparison of cardiac and
noncardiac pain
Noncardiac chest pain
Cardiac chest pain
Sharp, knifelike
Dull
Blood pressure
Stabbing sensation
Aching
Episodes of angina are normally accompanied by marked elevations in blood pressure, whereas blood pressure in MI may be normal but more commonly is decreased.
Aggravated by movement
Heaviness, oppressive feeling
Present only with breathing
Present at all times
Localized (patient able to point to one spot)
Generalized (occurs over a wider area)
Respiration Patients with either acute coronary syndrome may exhibit respiratory distress. Respiratory rate is increased while the depth of respiration may be more shallow than
Data obtained from Malamed SF: Beyond the basics: emergency medicine in dentistry, J Am Dent Assoc 128:843–854, 1997.
477
478
PART 7 CHEST PAIN
REFERENCES 1. Malamed SF: Beyond the basics: emergency medicine in dentistry, J Am Dent Assoc 128:843–854, 1997. 2. Kurz MC, Mattu A, Brady WJ: Acute coronary syndrome. In: Marx JA, Hockberger RS, Walls RM, editors: Rosen’s emergency medicine: concepts and clinical practice, ed 5, Elsevier Saunders, Philadelphia, 2014, pp. 997–1033. 3. Fallon EM, Roques J: Acute chest pain, AACN Clin Issues 8:383–397, 1997. 4. Lemire S: Assessment of clinical severity and investigation of uncomplicated gastroesophageal reflux disease and
noncardiac angina-like chest pain, Can J Gastroenterol 11:37B–40B, 1997. 5. Favretto G, Stritoni P: Pulmonary embolism: diagnostic algorithms, Ital Heart J 6:799–804, 2005. 6. Cayley ME: Chest pain, In: Bope ET, Kellerman RD e ditors: Conn’s current therapy, Elsevier Saunders, Philadelphia, 2014. 7. Heart attack, stroke & cardiac arrest warning signs, Dallas, American Heart Association, 2014. http://www.heart.org/ HEARTORG/General/Heart-Attack-Stroke-and-CardiacArrest-Warning-Signs. Accessed February 7, 2014.