Evaluating Chest PainWhat Are the Risks?

Jeffrey E. Keller MD

Badger Correctional Medicine

We Belong In Your Jail!

The Dilemma of Chest Pain

• On the one hand: I don’t want the words “Chest Pain” to become a get-out-of-jail-free card.

• On the other hand: I don’t want to get the phone call that begins, “Do you remember that patient you saw yesterday?”

Objectives

• Review Pathology and Terminology• Chest Pain Risk Assessment– Historical Risk Factors– Typical Presentation– Physical Examination

Objectives

• How can Cardiac Blood tests help you?• How can EKGs help you?• Setting up Chest Pain protocols in your

institution.

Atherosclerosis

• The build up of plaque in the coronary arteries obstructs flow.

Angina

• Coronary flow is restricted at high flow states.

• Stable Angina.– Predictable

• Unstable Angina.– Pre-MI pain

Myocardial infarction

• Coronary flow is suddenly cut off by a clot.

• This results in death of heart muscle.

• STEMI• NonSTEMI

ACS is a process stretching from stable angina to myocardial infarction.

ACS Continuum

Atherosclerosis----

Angina-----

Unstable Angina------

Myocardial Infarction-------

Dead

Risk Stratification

• Risk Stratification is the process by which we assess the risk involved in any situation.

• Which of these has the highest risk of drowning?

• Swimming the English Channel.

• Sitting in a bathtub.

Risk Stratification

• What is an acceptable “Miss Rate?”• Ranges between 2-6%• Cannot do better than 2%• Attempts to do better than this will harm

more people than help.

Risk Assessment Step OneDoes the patient have Atherosclerotic

heart disease?

• Known Coronary Heart Disease• Other Atherosclerotic Process• Smoking, Age, Family History, Diabetes,

Hypertension• Male, Obesity, Cholesterol

ACS Presentation

Typical MI: Substernal, heavy, radiates to arms and neck/jaw, sweaty, SOB, nausea, urge to defecate.

Typical Angina: Comes and goes, precipitated by heart working harder (exercise, eating, night), lasts only minutes and goes away.

Atypical Presentation

Atypical: Other pain patterns (like not substernal—off to the side), localized pain, pleuritic pain, no radiation, no pain, just SOB, exercise intolerance, weakness, nothing

Who has atypical symptoms? Older, women, diabetics, chronic disease.

Who is more likely to have typical symptoms? Young, healthy males—precisely who we tend to have in correctional facilities

Physical Examination

– Ausculation rarely helpful

– Rarely—pulmonary edema

– Diaphoresis, gray.– Overall gestalt of sick

or not sick

Assigning Risk—High or Low

• 56 year old who had coronary stents placed five years ago now states he has substernal chest pain going into his jaw. He looks grey and ill.

• 21 year old who complains of stabbing in his chest “like needles” plus numbness of both of his legs. No risk factors. His sternum is tender to palpation.

Is H & P Alone Accurate?

• 2-4% miss rate.• Scoring systems do no

better.• Goldman’s Criteria.• Can tests improve on

this?

Bayesian Analysis

• How much will a test change probability?• Sometimes it does, sometimes it does not and

sometimes it makes things worse.• Assign a probability and then evaluate the

test.

Bayesian Analysis

• Step one—assign a risk based on history and physical

• Step two—do a test and, depending on whether it is positive or negative, change the risk assessment.

• Step three. Analyze whether the test has improved your risk assessment.

Tests

– Sensitivity: How accurate is the test at finding the disease.

– False negative: When a test fails to find the disease.

– Specificity: How accurate is the test at excluding the healthy.

– False Positive: When a test is positive in patients without the disease.

Core Concepts

• Tests can be harmful as well as helpful.• Incidence of false positive and false negative

are related to the overall incidence of the disease in the community.

• The sensitivity and specificity of a test determine how much a test will change pre-test probability.

ACS Tests

• Overall incidence of disease in the community.• Sensitivity and specificity of the test.• What is the potential harm?

Troponin I

• Troponin is released by damaged heart muscle.

• Levels over 0.5 are almost always diagnostic of acute MI.

• It rises around three hours after the onset of the MI and stays up for several days.

Troponin

– ER protocol: 3 sets in 6 hours.– False positive: Intermediate result >0.1 and <0.5– False negative: Angina. Early MI.

Normal Troponin Series

Atherosclerosis----

Angina-----

Unstable Angina------

Myocardial Infarction-------

Dead

Troponin case

• 56 year old who had coronary stents placed five years ago now states he has had substernal chest pain going into his jaw for the last 45 minutes. He looks grey and ill.

• Troponin I is negative.• What have you learned?

EKGs

• Normal• STEMI pattern• Nonspecific

Normal EKG

Acute STEMI

STEMI?

STEMI?

Nonspecific EKG

Limitations of EKGs

• Sometimes they are normal in people having an MI.

• Sometimes they are abnormal in people who are not having heart pain.

• The machine readings are often inaccurate.

EKG Summary

• EKGs must be interpreted with the initial Risk Assessment in mind.

• If a patient initially was high risk and has a normal EKG, he is still at high risk.

Do Chest Pain tests help?

– High Risk patient, positive test: Confirms what we know. Consult a cardiologist.

– High Risk, negative test. Does not exclude disease. Does not lower risk much. Still must pursue further.

– Low risk, negative test: Confirms what we already knew.

– Low risk, Positive test: Likely a false positive, but now must pursue further evaluation.

Further work up required

• Stress EKG• Thallium stress EKG• Angiogram• CT angiogram• Cardiology Consultation

Documentation

• Historical Risk factors• History of Typical or Atypical symptoms.• Physical Exam• Assessment• Alternative diagnosis• Follow-up.

Chest Pain

• One of the scariest complaints we confront.• In actual fact, chest pain carries less long term

risk than do other common jail complaints:– Alcohol withdrawal– Drug dependency– Suicide.

Chest Pain in Corrections

• Everyone here can pretty accurately assign risk based on a patient’s risk factors, symptoms and physical exam.

• Using EKGs and Cardiac Markers to modify that assessment is tricky.

• If you are going to use them, you must use them correctly.

Cardiac Marker recommendations

• Use only Troponin I.• If you order one, you have to order at least

one more at least three hours later.• If they are negative, you must follow them up

with further testing.

EKG in Corrections

Do not make these two mistakes:

Do not assume that a normal EKG means that the patient has a normal heart.

Do not do EKGs in patients with low risk.

Review: Case #1

• 21 year old who complains of stabbing in his chest “like needles” plus numbness of both of his legs. He is short of breath.

• Risk assessment for cardiac pain:• EKG?• Labs?• Consult?

Review Case # 2

• 56 year old who had coronary stents placed five years ago now states he has substernal chest pain going into his jaw. He looks grey and ill.

• Risk assessment for cardiac pain:• EKG?• Labs?• Consult?

Review Case # 3

• A 24 year old comes into the jail high on Methamphetamine. He complains of chest pain. His heart rate is 140.

• Risk assessment for cardiac pain:• EKG?• Labs?• Consult?

Review case # 4

• A 36 year old man comes to the jail medical clinic stating that he has had chest pain steadily for the last four days. He points to his left sternal border. It hurts worse when he breathes. The pain radiates to his left arm.

• Risk assessment for cardiac pain:• EKG?• Labs?• Consult?

Review case # 4

• A 61 year old diabetic man states that he gets a little short of breath off an on during the day. He has no chest pain, but he states that sometimes he gets a cramp in his jaw. He has coronary stents placed 7 years ago. He feels fine right now.

• Risk assessment for cardiac pain:• EKG?• Labs?• Consult?