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.