Transcript Sensitivity and Specificity

Sensitivity and Specificity
GOLD STANDARD
SnNOUT (Rules out 60%)
Sensitivity is
TMT + VE
CAD
by CAG
No CAD
by CAG
True Positives
60
False Positives
60
True positives
60
Total CAD
100
TEST
Specificity is
TMT – VE
False Negative
40
True Negatives
240
Total CAD
100
Total No CAD
300
True Negatives
240
Total No CAD
300
SpPIN (Confirms 80%)
Indications of Exercise Test
Atypical and typical Chest pain CV risk profile
Unstable Angina – Decision on need for CAG
Risk stratification after MI and assess CABG
To prescribe exercise in CAD / Athelets
Asymptomatic pt without CV Risk factors ??
Pre Test Probability of CAD
by Symptoms, Gender and Age
Age
Gender
Typical/Definite
Angina Pectoris
30-39
30-39
Males
Intermediate
Intermediate
low (<10%)
Very low (<5%)
Females
Intermediate
Very Low (<5%)
Very low
Very low
40-49
Males
High (>90%)
Intermediate
Intermediate
low
40-49
Females
Intermediate
Low
Very low
Very low
50-59
Males
High (>90%)
Intermediate
Intermediate
Low
50-59
Females
Intermediate
Intermediate
Low
Very low
60-69
Males
High
Intermediate
Intermediate
Low
60-69
Females
High
Intermediate
Intermediate
Low
High = >75%
Atypical/Probable Non-Anginal
Angina Pectoris Chest Pain
Intermediate = 15-75%
Low = <15%
Asymptomatic
Very Low = < 5%
CAD Testing Algorithm
Clinical
Presentation
CV Risk
Factors
Low (<20%)
Derive Pretest
Probability
Intermediate
20% to 75%
High ( >75%)
Use a computer model or
Use the probability table
No Testing
Stress Testing
Angiography
Testing Algorithm contd..
Intermediate Probability
20% - 75%
Assess ECG and
Exercise Tolerance
Normal ECG
Abnormal ECG or
Can exercise
Can’t exercise
Treadmill test
Duke score
Negative
No more testing
Positive
MPI or ESE or CSE
Angiography
Absolute contra indications for ETT
• Acute myocardial infarction
(within 2 days)
• High-risk unstable angina
• Uncontrolled cardiac arrhythmias
• Symptomatic severe aortic stenosis
• Uncontrolled symptomatic heart
failure
• Acute pulmonary embolus or
pulmonary infarction
• Acute myocarditis or pericarditis
• Acute aortic dissection
Indications to terminate ETT
• Drop in SBP of >10 mm Hg from
baseline BP with accompanying
evidence of ischemia
• Moderate to severe angina
• Nervousness, ataxia, dizziness
• Poor perfusion - cyanosis or pallor
• Difficulty in monitoring ECG /SBP
• Subject’s desire to stop;
• Sustained ventricular tachycardia
• ST elevation (≥1.0 mm)