Best Dx/Best Rx: Chronic Stable Angina

From: Subject: Best Dx/Best Rx: Chronic Stable Angina Date: Wed, 3 Jun 2009 21:47:15 -0700 MIME-Version: 1.0 Content-Type: multipart/related; type="text/html"; boundary="----=_NextPart_000_024B_01C9E494.DBCBA960" X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 This is a multi-part message in MIME format. ------=_NextPart_000_024B_01C9E494.DBCBA960 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Content-Location: http://www.acpmedicine.com/acp/newrxdx/rxdx/dxrx0109.htm Best Dx/Best Rx: Chronic Stable Angina

Chronic = Stable=20 Angina

Paul R. Sutton, M.D., Ph.D., F.A.C.P.
Stephan D. Fihn, M.D., M.P.H., F.A.C.P.
University = of=20 Washington School of Medicine

Defin= ition/Key=20 Clinical Features
Diffe= rential=20 Diagnosis
Best = Tests
Best = Therapy
Best = References

Definition/Key=20 Clinical Features

A pattern of chest pain or discomfort caused = by=20 myocardial ischemia=20
- No appreciable change in frequency or = severity for ≥ 2=20 mo
- Pain is provoked by exertions or stresses of = similar=20 intensity
Precedes MI in about half of cases; common=20 afterward

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Differential = Diagnosis

Nonischemic heart disease=20
- Arrhythmias (palpitations or typical = angina)=20
- Aortic stenosis (typical angina, often=20 exertional)=20
- Aortic dissection ("tearing" pain, often of = abrupt=20 onset)=20
- Pericarditis (often pleuritic pain but may = be anginal;=20 often relieved by sitting up and leaning forward)
Pulmonary disease=20
- Pulmonary embolus (usually no chest pain but = may cause=20 pleuritic pain; associated dyspnea)=20
- Pneumothorax (acute onset, pleuritic pain, = associated=20 dyspnea)=20
- Pneumonia (pleuritic pain)
Gastrointestinal disease=20
- Gastroesophageal reflux (may be = indistinguishable from=20 angina)=20
- Acid peptic disease (may be = indistinguishable from=20 angina)=20
- Biliary disease (RUQ pain that radiates to = back or=20 scapula)=20
- Pancreatitis ("boring" epigastric pain, may = radiate to=20 back)
Chest wall or dermatologic pain = (characteristically=20 reproduced with palpation or movement)=20
- Costochondritis=20
- Rib fracture=20
- Sternoclavicular arthritis=20
- Herpes zoster=20
- Myofascial pain
Psychiatric disorders (may be distinguishable = from=20 angina)=20
- Anxiety disorders=20
- Affective disorders (e.g., = depression)=20
- Somatoform disorders=20
- Thought disorders (e.g., fixed = delusions)=20
- Factitious disorders (e.g., M=FCnchausen=20 syndrome)

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Best=20 Tests

Patient history=20
- Use to estimate pretest probability of = significant=20 ischemic heart disease (>70% stenosis of one or more coronary = arteries)=20 based on symptom characteristics and risk factors=20
- Symptoms of typical angina=20
  - Substernal pain; may radiate to neck, jaw, = shoulder,=20 arms=20
  - Dull, aching, pressurelike in character; = difficult=20 to localize precisely=20
  - Typically < 5 min in duration=20
  - Exacerbated by exertion or emotional = stress;=20 relieved by rest or nitroglycerin=20
  - May be associated with diaphoresis, = nausea,=20 palpitations, light-headedness, dyspnea
- Risk factors=20
  - Older age=20
  - Male gender; for women, status post = menopause=20
Cigarette smoking=20
- Abnormal lipids (high LDL, low HDL = cholesterol)=20
- Diabetes=20
- Sedentary lifestyle=20
- Hypertension=20
- Cerebrovascular disease=20
- Peripheral vascular disease=20
- Family history of premature coronary artery=20 disease
Physical examination=20
- Often normal=20
- Signs of hypertension=20
  - Elevated blood pressure=20
  - Enlarged or laterally displace point of = maximum=20 impulse=20
  - S₄ gallop=20
  - Retinal vascular changes
- Stigmata of genetic dyslipidemia syndromes = (e.g.,=20 xanthelasma)=20
- Possible findings during episode of angina =
  - S₄ or S₃ = gallop=20
  - Mitral regurgitation murmur=20
  - Paradoxically split S₂=20
  - Bibasilar crackles=20
  - Chest wall heave =
Resting 12-lead ECG=20
- Pathologic Q waves pathognomonic for = ischemic heart=20 disease (IHD)=20
  - Isolated Q waves in lead III or QS pattern = in V1 and=20 V2 nonspecific
- ST depression, T wave inversion, and left = ventricular=20 hypertrophy favor diagnosis of angina=20
- ECG normal in 50% of patients with chronic = stable=20 angina
Laboratory tests=20
- Serum hemoglobin=20
- Fasting glucose=20
- Fasting lipid panel=20
  - Total cholesterol=20
  - HDL cholesterol=20
  - Triglycerides=20
  - Calculated LDL cholesterol =
Imaging studies=20
- Chest radiograph or CT if signs or symptoms = of the=20 following:=20
  - Congestive heart failure=20
  - Valvular heart disease=20
  - Pericardial disease=20
  - Aortic dissection=20
  - Aortic aneurysm
- Echocardiography or multigated equilibrium=20 radionuclide angiography if suspected left ventricular = impairment=20
Noninvasive testing=20
- Objectives=20
  - Ascertain probability of clinically = important=20 IHD=20
  - Estimate risk of a serious cardiovascular = event=20 (e.g., MI or sudden death)
- Most likely to influence clinical decisions = when=20 pretest probability of IHD is intermediate; also useful to assess = risk and=20 prognosis when probability is high=20
- Sensitivity reduced by beta blockade = (withhold beta=20 blockers for four half-lives [~ 48 hr] before testing)=20
- ECG exercise testing (sensitivity, 68%; = specificity,=20 77%)=20
  - First-choice diagnostic test for average = patient=20 with intermediate pretest probability of IHD and normal resting = ECG=20
  - Widely available; inexpensive=20
  - Generally safe=20
  - Exercise capacity strong prognostic = indicator=20
  - Sensitivity reduced by digoxin (causes = resting ST=20 segment depression)=20
  - Contraindications=20
    
    Inability to perform exercise=20
    Previous coronary = revascularization=20
    ECG abnormalities that would interfere = with=20 interpretation of exercise ECG
- Stress radionuclide myocardial perfusion=20 imaging=20
  - Greater diagnostic sensitivity than ECG = exercise=20 testing (range, 80%=9685%)=20
  - Requires specialized setting=20
  - Exercise or pharmacologic agents to induce = stress=20
  - Preferred in patients with ECG = abnormalities that=20 interfere with interpretation of ECG exercise testing=20
  - May be considered after nondiagnostic = exercise=20 ECG=20
  - Allows estimation of left ventricular = systolic size=20 and function
- Stress echocardiography=20
  - Alternative choice in patients with ECG=20 abnormalities that interfere with ECG exercise testing=20
  - Exercise or pharmacologic agents to induce = stress=20
  - Sensitivity, 80%=9685%; specificity = marginally higher=20 than other noninvasive tests; less sensitive in very obese = patients=20
Invasive testing=20
- Coronary angiography=20
  - Unequaled coronary artery detail=20
  - Powerful prognostic tool=20
  - Expensive=20
  - Risk of plaque rupture=20
  - Inconsistent assessment of functional = stability and=20 significance of lesions=20
  - Indications=20
    
    High probability of high-risk IHD =
    Survival of sudden death=20
    Urgency to confirm or refute diagnosis = of=20 IHD=20
    Nondiagnostic noninvasive testing =
    Inability to undergo noninvasive = testing=20
    Suspected nonatherosclerotic = angina=20
    High pretest probability of left main = coronary or=20 three-vessel IHD

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Best=20 Therapy

Risk Stratification in Chronic Stable = Angina=20

Categories=20
- Low risk (< 1% mortality/yr)=20
  - Medical management without further = noninvasive=20 testing
- Intermediate risk (1%=963% = mortality/yr)=20
  - May require additional studies =
- High risk (> 3% mortality/yr)=20
  - May require additional studies=20
Anatomic factors=20
- Left ventricular systolic function
- Extent and severity of atherosclerotic = occlusion or=20 coronary tree=20
- Plaque stability (i.e., risk of plaque = rupture)=20
Clinical factors=20
- Age=20
- Gender=20
- Presence of typical angina=20
- Diabetes=20
  - Insulin use
- Prior MI

Nonpharmacologic Therapy to Reduce = Cardiovascular=20 Risk=20

Smoking cessation=20
Physical activity (moderate aerobic activity = 30 min/day,=20 5=967 days/wk)=20
Dietary modification (calorie restricted if = overweight;=20 high in fresh fruits and vegetables; high in fiber; low in saturated=20 fats)

Drug Therapy to Reduce=20 Cardiovascular Risk

Antiplatelet agents=20
- Aspirin=20
- Aspirin alternatives=20
  - Clopidogrel=20
  - Ticlopidine (rarely used) =
- Lipid-lowering agents=20
  - Therapeutic goal: serum LDL cholesterol = < 100=20 mg/dl (perhaps < 70 mg/dl for selected high-risk = patients)=20
  - Statins=20
  - Niacin=20
  - Fibric acid derivatives
  - Bile acid sequestrants
- Antihypertensive therapy=20
- ACE inhibitors

Drug Therapy for Anginal = Symptoms

Beta blockers=20
- Titrate dose to reduce resting heart rate to = 55 to 60=20 beats/min
Calcium channel blockers=20
Nitrates and nitroglycerin

Invasive Therapy=20

Revascularization=20
- Percutaneous coronary intervention, with or = without=20 intracoronary stent=20
- Coronary artery bypass graft=20

Follow-up=20

Reassess patient periodically (4- to = 12=96month intervals)=20 for the following:=20
- Changes in level of activity=20
- Changes in frequency or severity of anginal=20 symptoms=20
- Whether current therapy is well = tolerated=20
- Patient success in modifying cardiac risk=20 factors=20
- Development of new or worsening comorbid = illnesses=20 that may affect angina

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Best=20 References

Expert Panel on Detection, Evaluation, and = Treatment of=20 High Blood Cholesterol in Adults (Adult Treatment Panel III): JAMA = 285:2486,=20 2001 [PMID 11368702]

Gibbons RJ, et al: Circulation 99:2829, 1999 = [PMID=20 10351980]

Gibbons RJ, et al: J Am Coll Cardiol 41:159, 2003 = [PMID=20 12570960]

Grundy SM, et al: Circulation 100:1481, 1999 = [PMID=20 10500053]

Grundy SM, et al: J Am Coll Cardiol 44:720, 2004 = [PMID=20 15358046]

February 2006