Exercise Management Angina and Silent Ischemia Chapter 08

Exercise ManagementExercise Management

Angina and Silent Angina and Silent IschemiaIschemiaChapter 08Chapter 08

• PathophysiologyPathophysiology• Ischemia may be Ischemia may be

symptomatic or symptomatic or silentsilent

• Symptomatic Symptomatic ischemia may be ischemia may be present in several present in several ways. The most ways. The most common is angina.common is angina.

• Symptomatic Symptomatic angina is divided angina is divided into three forms: into three forms: stable, unstable, stable, unstable, and variant (also and variant (also called vasospastic called vasospastic or Prinzmetal's or Prinzmetal's angina).angina).

Coronary IschemiaCoronary Ischemia

Exercise Management – Angina and Silent Exercise Management – Angina and Silent IschemiaIschemia

• Stable AnginaStable Angina

• is reproducibly associated with a specific is reproducibly associated with a specific amount of physical exertion, emotional amount of physical exertion, emotional stress, or exposure to cold stress, or exposure to cold

• is predictably relieved promptly with rest is predictably relieved promptly with rest or sublingual nitroglycerin.or sublingual nitroglycerin.

• is associated with an ischemic event due is associated with an ischemic event due to a coronary artery stenosisto a coronary artery stenosis


• Unstable angina Unstable angina (UA) (UA) • occurs unpredictably. It indicates intermittent occurs unpredictably. It indicates intermittent

complete blockage of an artery which may soon complete blockage of an artery which may soon become permanent. become permanent.

• The The threethree principal presentations of UA are: principal presentations of UA are:• angina that occurs at rest angina that occurs at rest oror upon awakening upon awakening

from sleep, lasting more than 20 min;from sleep, lasting more than 20 min;• new onset, or first experience, of anginal chest new onset, or first experience, of anginal chest

pain; andpain; and• increasing severity, frequency, duration, or increasing severity, frequency, duration, or

threshold pattern (level of activity that threshold pattern (level of activity that reproduces the pain) of previously diagnosed reproduces the pain) of previously diagnosed angina.angina.


• The pathogenesis of UA is multi-factorial and The pathogenesis of UA is multi-factorial and includes one or more of the following:includes one or more of the following:

• platelet aggregation or thrombosis (clot) at a site platelet aggregation or thrombosis (clot) at a site of coronary artery narrowing;of coronary artery narrowing;

• rupture and hemorrhage into an atherosclerotic rupture and hemorrhage into an atherosclerotic plaque; andplaque; and

• transient periods of vasospasm at the transient periods of vasospasm at the atherosclerotic plaque.atherosclerotic plaque.

** Often, UA is a precursor to MIOften, UA is a precursor to MI . People with this form . People with this formof angina must be admitted to a coronary care unit andof angina must be admitted to a coronary care unit andtreated immediately with anti-clotting (anticoagulant)treated immediately with anti-clotting (anticoagulant)drugs or emergency balloon angioplasty.drugs or emergency balloon angioplasty.


• Variant, vasospastic, Variant, vasospastic, or or Prinzmetal's angina • Occurs when the coronary arteries spasm, Occurs when the coronary arteries spasm,

or contract suddenly.or contract suddenly.• Angiograms in this type of angina show no Angiograms in this type of angina show no

obstruction or stenoses, and very little obstruction or stenoses, and very little evidence of atheroma. evidence of atheroma.

• Intense vasospasm (i.e., a form of cramp Intense vasospasm (i.e., a form of cramp of the vessel wall muscles) alone reduces of the vessel wall muscles) alone reduces coronary oxygen supply and results in coronary oxygen supply and results in angina. This leads to transient narrowing. angina. This leads to transient narrowing.

• Treatments with medications that Treatments with medications that decrease spasm, such as calcium-channel decrease spasm, such as calcium-channel antagonists, are often effective.antagonists, are often effective.


• Effects on the Exercise ResponseEffects on the Exercise Response• People with exercise-related myocardial People with exercise-related myocardial

ischemia may need to stop a single ischemia may need to stop a single session of physical activity prematurely.session of physical activity prematurely.

• This may result from abnormal This may result from abnormal hemodynamic responses. hemodynamic responses. • a reduction occurs in the production of nitric a reduction occurs in the production of nitric

oxide (inhibiting dilation), of the coronary oxide (inhibiting dilation), of the coronary artery and promoting vasoconstriction. artery and promoting vasoconstriction.

• Also, with diseased arteries, increased platelet Also, with diseased arteries, increased platelet aggregation causes release of aggregation causes release of thromboxane A2, a chemical that strongly constricts blood , a chemical that strongly constricts blood vessels. vessels.


• Effects on the Exercise ResponseEffects on the Exercise Response

• Since the myocardial cells are not well Since the myocardial cells are not well perfused with oxygen, they can not contract perfused with oxygen, they can not contract well. well.

• This reduces stroke volume and left ventricular This reduces stroke volume and left ventricular ejection fraction. ejection fraction.

• The reduction in stroke volume limits cardiac The reduction in stroke volume limits cardiac output and promotes fatigue. output and promotes fatigue.

• The decreased stroke volume may lead to The decreased stroke volume may lead to compensatory increases in heart rate, known compensatory increases in heart rate, known as increased chronotropic response, thus, a as increased chronotropic response, thus, a longer warm-up is needed during exercise.longer warm-up is needed during exercise.


• Effects of Exercise Training• The overall goal for people with angina is to raise

the ischemic threshold, or the point during physical stress at which angina symptoms occur

• With exercise training, a decrease in the severity and extent of exercise-related myocardial ischemia occurs via a reduction in myocardial oxygen demand. (RPP used to indirectly measure MVO2 )

• Myocardial oxygen demand is reduced by • 1) increasing vagal tone, which• 2) decreases heart rate, which • 3) increases ventricular filling time. • 4) the increased filling time produces increased end

diastolic volume, and an increased stroke volume

• Exercise training improves nitric oxide production


• Effects of Exercise TrainingEffects of Exercise Training

• There is a reduction the exercise systolic There is a reduction the exercise systolic blood pressure because of an improved blood pressure because of an improved myocardial supply (vasodilatation) myocardial supply (vasodilatation)

• This allows for a reduced double product This allows for a reduced double product at a given exercise workload, thus the at a given exercise workload, thus the symptomatic ischemic threshold is raisedsymptomatic ischemic threshold is raised

• Therefore the patient will be able to Therefore the patient will be able to perform a more intense physical activity perform a more intense physical activity before exceeding the double product that before exceeding the double product that elicits angina.elicits angina.



• Exercise training increases the supply of blood and oxygen to the heart at rest and during exercise. • With long-term exercise training (e.g., 4-7

times/wk for > 12 wk), there is repeated laminar shear stress on the surface of the coronary endothelial cells of the arterioles. This stress changes the shape of the endothelial cells in the direction of the blood flow, and stimulates the production of nitric oxide, promoting vasodilation.



• With repeated exercise training, there is an With repeated exercise training, there is an improvement in calcium handling of the improvement in calcium handling of the smooth muscle cells. This leads to a smooth muscle cells. This leads to a decreasedecrease in coronary tone (vasoconstriction) and an in coronary tone (vasoconstriction) and an increase in the vasodilatation (relaxation) of increase in the vasodilatation (relaxation) of the coronary arteries.the coronary arteries.


• Management and MedicationsManagement and Medications

• The primary goals for treatment of The primary goals for treatment of myocardial ischemia are to myocardial ischemia are to increaseincrease myocardial supply and myocardial supply and decreasedecrease myocardial demand. Primary myocardial demand. Primary management used to decrease myocardial management used to decrease myocardial oxygen demand includes medications and oxygen demand includes medications and exercise.exercise.


• Recommendations for Exercise TestingRecommendations for Exercise Testing• See pg. 69 text, next slide, for summary chartSee pg. 69 text, next slide, for summary chart• Evaluation of people suspected of having CAD Evaluation of people suspected of having CAD

that may cause ischemia is primarily done with that may cause ischemia is primarily done with graded exercise testing and may not be safe graded exercise testing and may not be safe for all people with ischemia.for all people with ischemia.

• Exercise testing is Exercise testing is contraindicatedcontraindicated in people in people with acute ischemia and UA. May be with acute ischemia and UA. May be performed in persons with non-diagnostic performed in persons with non-diagnostic ECGs, negative cardiac biomarkers, and no ECGs, negative cardiac biomarkers, and no resting angina within the past six hours. resting angina within the past six hours. Angina must be evaluated and rated during Angina must be evaluated and rated during testing.testing.



“Current evidence-based guidelines for the evaluation and treatment of UA/non-ST-segment elevation MI (NSTEMI) state that exercise testing is contraindicated in patients with acute ischemia but can be performed in patients with nondiagnostic electrocardiograms (ECGs), negative cardiac biomarkers, and no resting angina within the past 6 h. In addition to standard clinical measures obtained during exercise testing (HR, ECG, BP, signs and symptoms, etc.) anginal symptoms, rating of anginal pain, and the exact onset and duration of angina (if they occur) should be documented when testing patients with a history of angina.”

• Recommendations for Exercise TestingRecommendations for Exercise Testing• 12 lead ECG warranted12 lead ECG warranted• During the test, documentation of anginal During the test, documentation of anginal

symptoms, the rating of angina, and the exact symptoms, the rating of angina, and the exact onset and duration of angina should be carefully onset and duration of angina should be carefully documented.documented.

• Indications to terminate exercise testing :Indications to terminate exercise testing :• Absolute Indications and Relative Indications for Absolute Indications and Relative Indications for

TerminatingTerminating• Absolute Indications • Drop in SBP >10 mmHg from baseline despite an • Drop in SBP >10 mmHg from baseline despite an

increase in work rate, accompanied by other evidence of ischemia • increase in work rate, accompanied by other evidence of ischemia • Moderately severe angina (defined as 3 on standard 1-4 angina scale) • ST Moderately severe angina (defined as 3 on standard 1-4 angina scale) • ST elevation (+1.0 mm) in leads without diagnostic Q-waves (other than V1 or elevation (+1.0 mm) in leads without diagnostic Q-waves (other than V1 or aVR)aVR)

• Relative Indications • Drop in SBP >10 mmHg from baseline • Drop in SBP >10 mmHg from baseline despite an increase in work rate, in the absence of other evidence of despite an increase in work rate, in the absence of other evidence of ischemia • ST or QRS changes such as excessive ST depression (>2 ischemia • ST or QRS changes such as excessive ST depression (>2 mm horizontal or downsloping ST-segment depression) or marked mm horizontal or downsloping ST-segment depression) or marked axis shift axis shift


• Recommendations for Exercise TestingRecommendations for Exercise Testing• Specificity in diagnosing CAD can be Specificity in diagnosing CAD can be

further obtained by combining cardiac further obtained by combining cardiac imaging with the test.imaging with the test.• Myocardial perfusion imagingMyocardial perfusion imaging• Echocardiography to detect wall motionEchocardiography to detect wall motion

• In persons unable to exercise adequately In persons unable to exercise adequately enough to perform the exercise test, enough to perform the exercise test, pharmacological stress testing can be pharmacological stress testing can be used in conjunction with nuclear perfusion used in conjunction with nuclear perfusion imaging of the heart.imaging of the heart.


• Recommendations for Exercise TestingRecommendations for Exercise Testing• Pharmacological Stress TestingPharmacological Stress Testing• Intravenous Coronary Vasodilators - Intravenous Coronary Vasodilators - ( ex. ( ex.

Persantine)Persantine) These agents dilate normal These agents dilate normal coronary arteries more than diseased ones. coronary arteries more than diseased ones. Blood flow to the heart is assessed at rest Blood flow to the heart is assessed at rest and during infusion, along with and during infusion, along with simultaneous nuclear imaging with thallium simultaneous nuclear imaging with thallium or technetium. or technetium.

• Positive Chronotropic Positive Chronotropic (heart rate)(heart rate) and Inotropic and Inotropic

(contractility)(contractility) Agents, also known as Agents, also known as sympatho-mimetics . .


Exercise Programming (chart at end of slides)

•Prior to exercise training, people with angina must be able to:

• define angina;• define possible anginal symptoms;• identify their own anginal symptoms;• describe the immediate treatment (this includes understanding the necessity and protocol for

taking nitroglycerin in the event of an anginal attack); and

• understand the appropriate upper limits of exercise (including heart rate, ratings of perceived exertion, and angina scales).


• Exercise Programming• A prolonged warm-up and cool-down (>

10 min), has been shown to have an anti-anginal effect.

• Any changes in the angina frequency, type, or severity should be reported to the patient’s physician.

• The upper exercise intensity limit should be set at least 10 to 15 contractions/min below the RPP (double product) at the original ischemic threshold measured during the exercise test.


Exercise Programming Exercise Programming •In addition to the ischemic threshold, In addition to the ischemic threshold, the upper limit may be based on the upper limit may be based on ventricular dysrhythmia threshold or ventricular dysrhythmia threshold or inadequate blood pressure response inadequate blood pressure response threshold.threshold.

• The duration of the exercise session should The duration of the exercise session should use ischemic preconditioning (intervals), use ischemic preconditioning (intervals), exercise periods of short duration (e.g., 5-exercise periods of short duration (e.g., 5-10 min/session) separated by short rest 10 min/session) separated by short rest periods, 2 to 3 sessions/day.periods, 2 to 3 sessions/day.

• Frequency of exercise sessions may start Frequency of exercise sessions may start out high and decrease as longer duration out high and decrease as longer duration sessions beginsessions begin



End of PresentationEnd of Presentation


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Exercise Management Angina and Silent Ischemia Chapter 08