Sorting out chest pain in the office setting Anthony J. Viera, MD, MPH, FAHA Professor and Chair

Primary objectives Discuss the common causes of CP and incorporate epidemiology of CP into development of differential diagnosis Present an approach to evaluation of CP in the office setting Use principles of clinical epidemiology to understand when a stress test is and is not going to be helpful in evaluation of CP

Epidemiology of chest pain in family medicine settings Musculoskeletal 36 % 19 % Gastrointestinal 16 % “Nonspecific” 11 % Stable angina “Psychosocial” 7 % 5 % Pulmonary 4 % Non-ischemic cardiac Acute cardiac ischemia 2 %

The biggies 54 Acute coronary syndrome (AMI, USA) Pulmonary embolus (history, Wells) Aortic emergency In the ER setting, ___% of CP is due to serious cardiovascular etiology (AMI, USA, PE, CHF) 54

Other causes Pericarditis Arrhythmia Valve disease Pneumonia Pneumothorax Neoplasm Others?

Approach First order of business Assess for any acute life, threatening condition or other serious cardiovascular etiology Rapid history, exam (VS, overall appearance, heart & lungs) +/- ECG If one of the “biggies” is a legitimate consideration, then needs to be evaluated in the emergency department

Rational clinical exam… Which of the following has the strongest association with acute myocardial infarction? Pain radiating down left arm Pain radiating down right arm Pain radiating down both arms

Rational clinical exam… Which of the following has the strongest association with acute myocardial infarction? Pain radiating down left arm LR+ 2.3 Pain radiating down right arm LR+ 2.9 Pain radiating down both arms LR+ 7.1

Steps 1 & 2 History Electrocardiogram Acute MI? Acute ischemia?

46 y/o man with chest pain now Sinus bradycardia ST & T wave abnormalities suggesting myocardial injury 1

58 y/o man with epigastric discomfort last night Sinus tachycardia LAD Inf Q wave MI ST elev II, III, avF 7

52 y/o woman with substernal CP Sinus tachycardia Acute (anteroseptal Q wave) MI ST & T wave abnormalities suggesting myocardial ischemia suggesting myocardial injury 13

24 y/o man with brief sharp pain in chest two weeks ago Sinus bradycardia Early repolarization 25

59 y/o man with several days of CP and cough Sinus rhythm Diffuse ST elevation Peaked T’s inferiorly Findings suggest acute pericarditis 27

If not an emergency, is CAD (i.e., stable angina) a consideration? No (not really) Consider diagnoses: Musculoskeletal GERD/esoph spasm Panic disorder Somatoform sensations and worries

Musculoskeletal What is the pretest probability that someone coming to clinic with chest pain has a musculoskeletal etiology? History Exam Reproducible: LR+ 12.00 LR-0.78 Caution

GERD/esophageal spasm About one out of 5 clinic CP patients History Exam not helpful Empiric trial may be your best “test”

Panic attack “In the past 6 months, did you ever have a spell or attack when all of a sudden you felt frightened, anxious, or very uneasy?” “In the past 6 months, did you ever have a spell or attack when for no reason your heart suddenly began to race, you felt faint, or you could not catch your breath?”

Panic attack “No” to both questions is helpful Others Lowers from about 8% pretest to about 1% posttest Others Fear of “going crazy” Feeling of “unreality” (derealization) Feeling of “being outside of oneself” (depersonalization)

A perception among clinicians (and patients): A normal test result is enough to reassure a patient that nothing is wrong Is it?

McDonald IG, et al. Opening Pandora’s box: the unpredictability of reassurance by normal test result. BMJ 1996:313:329-32. 6 university cardiologists recruited 40 patients to exclude heart disease 30 asymptomatic w/ systolic murmur heard, 10 w/ palpitations Anxiety level before and after (asap and 9-12 mos) echocardiogram Echo normal in 37; only 1 had significant abnormality 30/38 had pretest anxiety (all 10 w/sxs) 55 % of the asymptomatic pts had residual anxiety _______of symptomatic pts had residual anxiety 100 %

If not an emergency, is CAD (i.e., stable angina) a consideration? No (not really) Consider diagnoses: Musculoskeletal GERD/esoph spasm Panic disorder Somatoform sensations and worries Yes Consider stress test Assign a pretest probability Determine if a stress test (and which type) will “move” that probability in any meaningful way

Pretest probability Kind of chest pain Age Sex Typical = SS, brought on by exertion, relieved by rest Atypical = 2 out of 3 Nonanginal = 1 out of 3 Age Sex

Diamond and Forrester

Test / treat threshold Test Treat 0% 100% ? Test Treat

Test / treat threshold <10% = don’t test (& don’t treat) 10-90 = testing zone >90% = don’t test, just treat (with cath)

ETT Sensitivity ~68% Specificity ~77%

Sample patient 38 y/o man with diffuse (left and right) CP while running on treadmill Relieved after about 15 minutes once run stopped Typical, atypical, or nonanginal?

Diamond and Forrester

Specificity * (1-pretest) Using a 2 X 2 table Positive disease Negative disease Positive test Negative test Sensitivity * pretest Specificity * (1-pretest) 22 78 100 Pretest probability of having disease Hypothetical sample of people

Using a 2 X 2 table Positive disease Negative disease Positive test Negative test 0.68*22 = 15 18 33 0.77*78 = 60 7 67 22 78 100 Pretest probability of having disease Hypothetical sample of people

Deriving post-test probability If positive ETT, the post-test probability = 15/33 = 45% If negative ETT, the post-test probability of having disease is 7/67 = 10%

How much does the ETT help? After a positive test (45%) After a negative test (10%) What now? Before the test (22%)

Bottom-line Very low or low – not going to help much Intermediate – most helpful But might need further testing (serial testing) High – not going to help all that much (if it’s negative, are you going to believe it?)

A brief ETT primer

Examples of ETT findings Patient 1 54 y/o man with a family history of CAD No chest pain

Pretest probability

Cath report

Patient 2 57 y/o man w/ episodes of sudden onset of heavy breathing & discomfort in the center of his chest with exertion Episodes last 10 minutes No h/o CAD, HTN, DM Remote history of smoking

Pretest probability

Duke treadmill score -18 estimates an annual cardiovascular mortality of 7% and a five year survival of 64% Using the Duke Score there is a high probability of severe angiographic coronary disease

Same day cath

2 days later

Don’t order a regular ETT if… Pt cannot walk on treadmill (for 6 minutes) Severe obesity – consider PET Pt has LBBB or enough baseline ST segment abnormality that will make it difficult to interpret (e.g., LVH with “strain”) Pt on digitalis

Summary The epidemiology of CP in the office setting is different than in the ER setting First step is still to assess for one of the biggies After that, use history and (to lesser extent) exam to guide you Consider pretest probability before ordering a stress test

Thank you for your attention! anthony.viera@duke.edu