management of stable angina pectoris bushra abdul hadi
TRANSCRIPT
Management of
Stable Angina Pectoris
Bushra Abdul Hadi
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.
Angina
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: Treatment Goals
• Feel better
• Live longer
Angina: Prognosis
• Left ventricular function
• Number of coronary arteries with significant stenosis
• Extent of jeoporized myocardium
Stable Angina
Risk stratification
• Noninvasive testing
• Cardiac catheterization
Stable AnginaEvaluation of LV Function
• Physical exam
• CXR
• Echocardiogram
Stable AnginaEvaluation of Ischemia
• History
• Baseline Electrocardiogram
• Exercise Testing
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 Testing
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
Stress Echo vs. Nuclear Stress
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 AnginaTreatment Options
• Medical Treatment
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-Blockers
Beta BlockersSide Effects
• Bronchospasm• Diminished exercise capacity• Negative inotropy• Sexual dysfunction• Bradyarrhythmia• Masking of hypoglycemia• Increased claudication• Hair loss
Beta BlockersCommon Available Agents
• Propranolol
• Atenolol
• Metoprolol
• Nadolol
• Timolol
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 BlockersMechanisms of Action
Calcium Channel BlockersMechanisms of Action
Calcium Channel BlockersSide Effects
• Palpitations
• Headache
• Ankle edema
• Gingival hyperplasia
Calcium Channel BlockersAvailable Agents
• Verapamil• Diltiazem• Nifedipine• Nicardipine• Amlodipine• Felodipine• Nisoldipine• Bepridil
Stable AnginaTreatment Options
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
NitratesSide Effects
• Headache
• Flushing
• Palpitations
• Tolerance
• 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 AnginaTreatment Options
• CABG
Stable AnginaResults of CABG
• 65% remain symptom-free at ten years
• 85% remain free of fatal/nonfatal MI at ten years
• Mortality of 2-3% yearly over ten years
• 2.5% incidence of perioperative MI
CABG vs. Medical Rx
• Three major randomized trialsA. VACSB. ECSSC. CASS
• Improved mortality in CABG groupA. L-main CADB. 3-vessel CAD, esp. with decreased EFC. LAD disease, severe angina, decreased EF
Stable Angina: CABG
• “Nevertheless, bypass grafting remains a palliative procedure, as is every known treatment for coronary disease, and it assure permanent freedom neither from symptoms nor from a fatal coronary event…”
Hull R. Tex Hrt Jnl 1989;16:127-129
Stable AnginaTreatment Options
• PTCA
PTCA vs. Medical Management
• Review of six major trials
• Greater symptomatic benefit in PTCA group
• No change in mortality or rates of MI
• Higher rate of CABG in PTCA group
BMJ 2000(Jul);321:73-77.
PTCA vs Medical ManagementMultivessel Disease
Stable AnginaResults of PTCA
• 80% or greater success rate
• 1% mortality
• 3-5% emergency CABG ( prior to stenting )
• 4% acute MI
CABG vs PTCAMultivessel Disease
• Review of six major randomized trials• Most patients had preserved LVEF• No differences in mortality or combined endpoint
of death and nonfatal MI• Second revascularization procedure more likely in
first year after PTCA• Surgery patients more likely to be angina free at
one year
CABG vs. PTCAMultivessel Disease
• Most patients had 2-vessel CAD, preserved LVEF, and “suitable” anatomy
CABG vs. PTCA
• BARI Trial Subset of Diabetic Patients
A. Five-year survival better in CABG group
B. Increased incidence of MI at eight years
C. More women, hypertension, CHF, and severe concomitant noncardiac disease
D. More multi-vessel disease, significant lesions, and distal lesions
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
Stable Angina: 3-Vessel CADTherapeutic Strategies
• CABG in patients with left-main disease or 3-vessel CAD and decreased LVEF
• PTCA or medical management an alternative in patients with 3-vessel CAD, mild symptoms, and preserved LVEF
Chronic Angia: Reading List
• Gersh BJ, Solomon AJ. Management of chronic stable angina: medical therapy, PTCA, and CABG. Ann Internal Med 1998(FEB);128:216-223.