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Angina Pectoris
• Classic angina is characterized by substernal squeezing chest pain, occurring with stress and relieved with rest or nitroglycerin.
• May radiate down the left arm
• May be associated with nausea, vomiting, or diaphoresis.
Stable AnginaClassification
• Exertional
• Variant
• Anginal Equivalent Syndrome
• Prinzmetal’s Angina
• Syndrome-X
• Silent Ischemia
Angina: Exertional
• Coronary artery obstructions are not sufficient to result in resting myocardial ischemia. However, when myocardial demand increases, ischemia results.
Angina: Variant Angina
• Transient impairment of coronary blood supply by vasospasm or platelet aggregation
• Majority of patients have an atherosclerotic plaque
• Generalized arterial hypersensitivity
• Long term prognosis very good
Angina: Anginal Equivalent Syndrome
• Patient’s with exertional dyspnea rather than exertional chest pain
• Caused by exercise induced left ventricular dysfunction
Angina: Prinzmetal’s Angina
• Spasm of a large coronary artery
• Transmural ischemia
• ST-Segment elevation at rest or with exercise
• Not very common
Angina: Syndrome X
• Typical, exertional angina with positive exercise stress test
• Anatomically normal coronary arteries• Reduced capacity of vasodilation in
microvasculature• Long term prognosis very good• Calcium channel blockers and beta blockers
effective
Angina: Silent Ischemia
• Very common
• More episodes of silent than painful ischemia in the same patient
• Difficult to diagnose
• Holter monitor
• Exercise testing
Angina: Prognosis
• Left ventricular function
• Number of coronary arteries with significant stenosis
• Extent of jeoporized myocardium
CCSC Angina Classification
• Class I
• Class II
• Class III
• Class IV
• Angina only with extreme exertion
• Angina with walking
1 to 2 blocks
• Angina with walking
1 block
• Angina with minimal activity
Stable AnginaExercise Testing
• The goal of exercise testing is to induce a controlled, temporary ischemic state during clinical and ECG observation
Angina: Exercise TestingHigh Risk Patients
• Significant ST-segment depression at low levels of exercise and/or heart rate<130
• Fall in systolic blood pressure
• Diminished exercise capacity
• Complex ventricular ectopy at low level of exercise
Angina: Exercise TestingLow Risk Group
CASS Registry: 7 year survival
• Less than 1 mm ST depression in Stage III of Bruce Protocol
• Annual mortality: 1.3%
JACC 1986;8:741-8
ECG Treadmill EST in Women
• Higher false-positive rate
• Reduces procedures without loss of diagnostic accuracy
• Only 30% of women need be referred for further testing
Stable AnginaGuidelines for Nuclear EST
Diagnosis/prognosis for CAD
• Non-diagnostic EST
• Abnormal resting ECG
• Negative EST with continued chest pain
• Intermediate probability of disease
Stable AnginaGuidelines for Nuclear EST
Defined CAD
• Post infarct risk stratification
• Risk stratification to determine need for
revascularization ( viability study )
Stable AnginaDipyridamole Nuclear EST
• Near equivalent sensitivity/specificity with symptom-limited nuclear EST
• Most useful in patients who cannot exercise
• Major contraindication is severe bronchospastic lung disease ( consider Dobutamine study )
Appropriateness of Radionuclide Exercise Testing
• Retrospective analysis of 1092 patients• 64% of tests ordered by cardiologists were
indicated• 30% of tests ordered by non-cardiologists
were indicated• Excessive charges from non-indicates tests
were $1,082,400Am J Card 1996;77:139-42
Stable AnginaStress Echo
• Ischemia may cause wall motion abnormalities, no rise of fall in LVEF
• Sensitivity/specificity same as nuclear testing
• May be better in women
Exercise TestingContraindications
• MI—impending or acute• Unstable angina• Acute myocarditis/pericarditis• Acute systemic illness• Severe aortic stenosis• Congestive heart failure• Severe hypertension• Uncontrolled cardiac arrhythmias
Stable AnginaNon-Invasive Evaluation
C oron ary A rte riog rap h y
L V D ys fu n c tion
C oron ary A rte riog rap h y
H ig h R isk
M ed ica l Th erap y
S tab le
C oron ary A rte riog rap h y
R ecu rren t A n g in a
M ed ica l Th erap y
L ow R isk
S tress Tes tin g
N orm a l L V F u n c tion
R es tin g L V F u n c tion(C lin ica l A ssessm en t)
N on d isab lin g A n g in a
Cardiac CatheterizationIndications
• Suspicion of multi-vessel CAD
• Determine if CABG/PTCA feasible
• Rule out CAD in patients with persistent/disabling chest pain and equivocal/normal noninvasive testing
Risk Factor Modification
• Hypertension
• Smoking
• Dyslipidemia
• Diabetes Mellitus
• Obesity
• Stress
• Homocysteine
Stable AnginaTreatment Options
M ed ic in e P ercu tan eou sIn te rva tion
C A B G
A n g in aTrea tm en t O p tion s
Stable AnginaCurrent Pharmacotherapy
• Beta-blockers
• Calcium channel blockers
• Nitrates
• Aspirin
• Statins
• ? ACE inhibitors
Stable AnginaConsiderations when Choosing a Drug
• Effect on myocardium
• Effect on cardiac conduction system
• Effect on coronary/systemic arteries
• Effect on venous capitance system
• Circadian rhytm
Beta-Blockers
• Decrease myocardial oxygen consumption
• Blunt exercise response
• Beta-one drugs have theoretical advantage
• Try to avoid drugs with intrinsic sympathomimetic activity
• First line therapy in all patients with angina if possible
Beta BlockersSide Effects
• Bronchospasm• Diminished exercise capacity• Negative inotropy• Sexual dysfunction• Bradyarrhythmia• Masking of hypoglycemia• Increased claudication• Hair loss
Calcium Channel BlockersMechanisms of Action
• Arterial dilation/after-load reduction
• Coronary arterial vasodilation
• Prevention of coronary vasoconstriction
• Enhancement of coronary collateral flow
• Improved subendocardial perfusion
• Slowing of heart rate with diltiazem, verapamil
Calcium Channel BlockersAvailable Agents
• Verapamil• Diltiazem• Nifedipine• Nicardipine• Amlodipine• Felodipine• Nisoldipine• Bepridil
NitratesMechanisms of Action
• Nitric oxide has been identified as endothelium-derived relaxing factor
• Organic nitrates are therapeutic precursors of endothelium-derived relaxing factor
NitratesMechanisms of Action
• Venous vasodilation/pre-load reduction
• Arterial dilation/after-load reduction
• Coronary arterial vasodilation
• Prevention of coronary vasoconstriction
• Enhancement of coronary collateral flow
• Antiplatelet and antithrombotic effects
NitratesReducing Tolerance
• Smaller doses
• Less frequent dosing
• Avoidance of long-acting formulations unless a prolonged nitrate-free interval is provided
• Build-in a nitrate-free interval o 8-12 hours
• To provide optimal benefit to patients, clinicians must use nitroglycerin more systematically and critically than they have before
W. Frischman
NitratesCommon Available Agents
• Isorbide dinitrate
• Isorbide mononitrate
• Long-acting transdermal patches
• Nitroglycerin sl
Stable Angina: 1-Vessel CADTherapeutic Strategies
• Initiate pharmacologic treatment
A. Nearly half of patients will become asymptomatic
• PTCA preferred alternative if medical therapy does not relieve angina or causes adverse effects
Stable Angina: 2-Vessel CADTherapeutic Strategies
• Initial medical management in patients with mild ischemic symptoms and normal LV function
• Revascularization in patients who fail medical therapy
• Selection of PTCA vs. CABG depends on coronary anatomy, LV function, need for complete revascularization, and patient preference