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									Approach to Chest Pain
     and Angina

             Part I
Diagnosis and Risk Stratification

   Mirek Otremba – Revised 2007
                   References
ACC/AHA Guideline on Chronic Stable Angina ‘02
     Circ. 1999; 99:2829-2848
     Update in JACC 2003; 41:159-168
     www.acc.org
CCS Consensus on Chronic Ischemic Heart
 Disease
     Can J Cardiol 2000; Vol 16 no. 12: 1515-1535
Chronic Stable Angina
     NEJM 2005; 352: 2524-34
Noninvasive tests in patients with stable CAD
     NEJM 2001; 344: 1840-1845
                 Objectives

•   How to make the diagnosis of angina or CAD
•   When to order further testing to make the
    diagnosis of angina
•   When to order further testing to determine
    prognosis (risk stratification)
•   To understand the limitations of various tests
              Clinical Scenario
A healthy 50 yr old man experienced 15 minutes of sharp,
epigastric, left sided chest pain while mowing the lawn.

He stopped and the pain resolved in 5 min. The pain did
not radiate and there was no diaphoresis or dyspnea.


     Does this patient have angina?

     How would you classify his symptoms?
            (ie typical, atypical angina, or non-cardiac chest pain)
  Classification of chest pain
Typical angina
  •      Substernal chest discomfort with characterstic quality and duration
  •      Provoked by exertion or emotional stress
  •      Relieved by rest or NTG



Atypical angina
      Meets 2 of the above characteristics

Noncardiac chest pain
   Meets one or none of the typical characteristics
 Classification of severity of angina

Class I
    No angina with ordinary physical activity
    Angina with strenuous/prolonged exertion
Class II
    Early-onset limitation of ordinary activity (2 blocks/1 flight)
    Worse after meals, in cold temp, or emotional stress
Class III
    Marked limitation of ordinary activity


Class IV
    Inability to carry out any physical activity without angina
    Angina occurs at rest
          History and Physical
You next ask about risk factors…
To increase pre-test probability
        Lipids, DM, HTN, smoking, and Fam. Hx
        Plus a past hx of PVD, or Stroke


…his father had an MI at the age of 50 yrs, and he is unaware
of his lipid status.
         History and Physical

You perform a focused physical looking
for signs of heart disease or a non cardiac
source of chest pain.
On examination he is moderately obese (BMI 30), with a BP
140/80, and HR 80. The cardiac and chest exam is normal.

His CBC, lytes, ECG and CXR are all normal

       What is his pre-test probability of CAD?
      Pre-test likelihood of CAD
        Nonanginal
                     Atypical angina   Typical angina
        chest pain
Age     M       F      M        F       M        F

35     3-35   1-19   8-59     2-39 30-88 10-78

45     9-47   2-22 21-70 5-43 51-92 20-79

55     23-59 4-25 45-79 10-47 80-95 38-82

65     49-69 9-29 71-86 20-51 93-97 56-84
Is the DIAGNOSIS established after the
         Hx/Px and initial tests?

Does the pt fit into one of the following?
  1.   Noncardiac c/p and low pretest prob…
           • No further testing needed.
           • Pt does not have angina
  2.   Diagnosis of angina is established (high pretest prob)
           • No further diagnostic testing needed.
           • Pt needs risk stratification for prognosis

  3.   Diagnosis is still not clear…(intermediate pretest prob)
           • Consider the following tests to make a diagnosis…
               Diagnosis of CAD
You decide to classify his chest pain as atypical,
and estimate his pre-test probability of CAD as
intermediate ( 65%)
                                  Nonanginal chest pain    Atypical angina    Typical angina

                            Age      M           F          M           F     M           F


                            35      3-35        1-19       8-59       2-39   30-88      10-78
 Is this high enough to
 give him a diagnosis of    45      9-47        2-22      21-70       5-43   51-92      20-79

 CAD and start treatment?
                            55     23-59        4-25      45-79      10-47   80-95      38-82


                            65     49-69        9-29      71-86      20-51   93-97      56-84

  How would you
  confirm the diagnosis?
     Diagnostic Tests for CAD
n   ECG Exercise Stress Testing (GXT)
n   Stress test plus imaging (nuclear or echo)
n   Pharmacologic testing (dipyridamole-MIBI, or
    Dobutamine-MIBI/Echo)
n   Angiography (gold standard test)


    What test is the most appropriate for him?
          DIAGNOSTIC Tests
            ACC/AHA Guidelines Circ. 1999; 99:2829-48



Exercise ECG (GXT) for diagnosis
  n   Class I
         Pts with intermediate pretest prob. (with normal ECG)
  n   Class IIa and IIb
         Suspected vasospastic angina
         Pts with high or low pretest prob of CAD
  n   Class III
         Baseline ECG abn. (LBBB, paced ECG, WPW, >1mm
         ST depression)

                       Click here to see the ACC/AHA classification system
              Diagnostic Tests
Stress imaging studies (nuclear or echo)
  n   Class I
         Pts with intermediate pretest prob. and abnormal
         ECG
  n   Class II
         Pts with low or high pretest prob. and abn. ECG
Pts unable to exercise…
  use pharmacological stress
  n Dypyridamole sestamibi or

  n Dobutamine echo/sestamibi
           Test Characteristics of
            Non-invasive testing
 Diagnostic
    test
                 Sn         Sp             LR +   LR -


Exercise Test    68         77              3     0.42


Nuclear Stress   88         77             3.8    0.16


 Stress Echo     76         88             6.3    0.27

                      …for occlusive CAD
                    2D ECHO
What about rest ECHO in the diagnosis of
chest pain or CAD?
Class I
        Pts with signs of AS or HOCM
        Pts with findings of CHF
  n   Class III
        Pts with none of the above findings
        i.e. routine echo is not indicated in the dx of angina
  Angiography (Gold standard)
How about angiography for diagnosis?
  n   Class I
        Pts who have survived sudden cardiac death
  n   Class II
        Pts with uncertain dx after noninvasive tests
        Pts who cannot undergo noninvasive tests
  n   Class III
        Pts who “want to know” but are low prob.
              Diagnostic Testing
You decide to order a routine treadmill test.
   n   Exercise time: 10 min (~10 METS)
   n   Symptoms: fatigue, no chest pain.
   n   HR and BP response: appropriate (80% predicted HR)
   n   ECG response: 1mm down sloping ST-segment depression in 3
       leads at peak exercise.




 How do you interpret this result?
      Does he have CAD? (what is post test probability)
      What is his Prognosis?
      Interpreting Exercise Tests
4 components to interpreting a stress test
       1. Symptoms (angina) during or after the test
       2. ECG changes during or after exercise
               ST depression > 1mm 80ms after J point
               ST elevation
       3. Hemodynamic response to exercise (HR and BP change)
       4. Workload in METs


Need to consider all 4 parts when interpreting test
  n   For prognosis:
        workload in METs is more important than ST changes
  n   Use the Duke Treadmill Score to calculate
      risk/prognosis
Our patient:


Fagan Nomogram
Post-test probability
of CAD = 85%




DTS score = 5

(formula and interpretation later)
Clinical symptoms may not predict
 coronary artery disease burden




                        Similar for women
Risk Stratification
              Risk Stratification
Once the clinical diagnosis of angina is probable or
 confirmed then the pt needs risk assessment

The choice of test is based on the pt’s ECG and
  physical ability
     •   Normal ECG – may use GXT (click to see AHA)
     •   With an abnormal ECG use stress imaging
     •   If unable to exercise use pharmacological stress
     •   For some patients angiography may be the best
         initial test (click to see AHA)
   Duke Treadmill Score (DTS)

DTS =         [exercise time (mins)] –
              [ 5 x ST segment deviation (mm)] –
              [ 4 x angina index ]   0 no angina
                                     1 angina occurs
                                        1 angina occurs
                                        2 angina reason for stopping test


 Risk (DTS)             4-yr survival         Annual mortality
 Low (>5)                   99%                      0.25%
 Mod (-10 to 4)             95%                      1.25%
 High (< -10 )              79%                           5%
      Imaging in risk stratification

§ Nuclear Imaging
  §   Normal imaging predicts good prognosis (<1 %/yr)


§ Stress Echo
  §   A negative test predicts a low risk for future events
        Risk dictates management
                                                     Our Patient:

§ Predicted annual mortality < 1 %
                                                     DTS 5 = Low Risk
   §   can be managed medically
                                                     Annual mortality = 0.25%
§ Pts with mortality 1-3 % / yr
   §   consider either cath or exercise imaging study for further risk
       assessment

§ Pts with mortality >3 % / yr
   §   should be referred for cath.
                  Summary
• Start with the Hx and P/E
  • estimate the pre-test probability of CAD
• Decide whether the patient needs testing
  • to make a diagnosis of CAD or
  • the diagnosis established clinically, but need
    testing to determine prognosis.
• Make decisions about therapy
  • medical vs. PCI/CABG
    • based on the patient’s risk assessment
THE END
ACC/AHA Classification System

Class I:     Conditions for which there is evidence and/or general
             agreement that a given procedure or treatment is useful
             or effective.
Class II:    Conditions for which there is conflicting evidence and/or
             divergence of opinion about the usefulness/efficacy of a
             procedure or treatment.
             Class IIa: weight of evidence/opinion in favor of
             usefulness
             ClassIIb: Usefulness less well established
Class III:   Conditions for which there is evidence and/or general
             agreement that the procedure/treatment is not
             useful/effective and in some cases may be harmful.


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       Exercise Testing for Risk
             Stratification
Exercise Testing for risk stratification and
  prognosis
  n   Class I
         Pts undergoing initial evaluation
         Pts with significant change in symptoms
  n   Class III
         Pts with severe comorbidity and not appropriate for
         revascularization

             Go Back
          Angiography for Risk
              Stratification
Angiography for risk assessment
  n   Class I
         Pts with CCS III or IV angina
         Pts with high risk noninvasive tests
         Pts with angina and CHF or poor LV function
  n   Class III
         Pts with angina responding to medical Tx and low
         risk or normal stress test


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