Clinical Electrocardiography: A Simplified Approach, 7th Edition (2006)

Part IV. SELF-ASSESSMENT PROBLEMS

Self-Assessment Problems

The final section of this textbook is a collection of 50 ECGs for review and self-assessment. These unknowns have been selected to challenge students and others who have completed the text or to serve as a stand-alone examination for clinicians who wish to take a board review–type “pretest.”

Each question comes with a short case description. (Helpful clues are sometimes provided.) Students are encouraged to write down their findings and compare their interpretations with the “official” answers given at the end of the section. Each question is worth 2 points. A perfect score is 100!

This section also gives answers to questions posed at the end of most chapters. Additional ECG questions and answers are freely available at a number of Internet sites including the ECG Wave-Maven: Self-Assessment Program for Students and Clinicians (http://ecg.bidmc.harvard.edu). This site includes more than 250 practice ECGs.

 

Questions

TRIAGE TRYOUT

These patients arrive in your office at the same time. Both complain of severe chest pain. One ambulance and one taxicab are available for transporting them to the nearest hospital, which is five miles away. What do you do?

Case 6 50-year-old man with chest pain

 

Case 7 50-year-old man with chest pain

 

 

FOUR CASES OF MISTAKEN IDENTITY

The following ECGs are commonly incorrectly identified as shown. For each ECG, what is your correct diagnosis?

Case 8 “Left bundle branch block or left ventricular hypertrophy with inferior myocardial infarction”

 

Case 9 “Complete heart block”

 

Case 10 “Sinus (or ectopic atrial) tachycardia”

 

Case 11 “Right axis deviation resulting from lateral wall infarction”

 

 

SYNCOPATED RHYTHMS

Both of these patients are complaining of an irregular heartbeat. What are the diagnoses?

Case 12

 

Case 13

 

 

INCOMPLETE DIAGNOSES OF COMPLETE RIGHT BUNDLE BRANCH BLOCK

Right bundle branch block was correctly diagnosed in these two patients with chest pain. That is only part of the story, however. What else is going on?

Case 14

 

Case 15

 

 

MORPHING P WAVES

What subtle arrhythmia is present in this ECG?

Case 16

 

 

TEARFUL PATIENT

Why is this very healthy female crying? (Clue: Consider QRS duration.)

Case 17

 

 

TRICKY BUSINESS

An ECG is obtained in this 45-year-old businessman before he undergoes appendectomy. He complains of lower left quadrant pain. The ECG is unchanged from a previous one, at which time the workup revealed normal cardiac function. What is the diagnosis?

Case 18

 

 

HEART FAILURE AFTER MYOCARDIAL INFARCTION

Two months after having a myocardial infarction, this 75-year-old man presents with rales on chest auscultation and an S3 gallop. His ECG is unchanged from a month ago and cardiac enzymes are negative. What does the ECG show?

Case 19

 

 

COMMON THEME

These elderly women have heart failure, and both complain of nausea. What are the two arrhythmias? What is the probable common underlying problem?

Case 20 (Clue: Previous ECGs showed atrial fibrillation with a rapid rate.)

 

Case 21 (Clue: Double-check leads II and V1.)

 

 

DRUG DILEMMA

This ECG (from a patient with normal electrolytes) is most consistent with therapy using which one of the following drugs?

 

a.   

Digoxin

 

b.   

Captopril

 

c.   

Amiodarone

 

d.   

Metoprolol

 

e.   

Verapamil

 

f.    

None of the above

Case 22

 

 

NARROWED-DOWN DIFFERENTIAL DIAGNOSES

The following patients both have narrowed heart valves. One has mitral stenosis, and the other has pulmonic stenosis. Can you tell which is which?

Case 23

 

Case 24

 

 

PAUSE FOR THOUGHT

A 72-year-old woman has intermittent light-headedness. What does the ECG lead show?

Case 25

 

 

LOOK-ALIKE TACHYCARDIAS

The following patients both complain of a fast heartbeat. One has atrial flutter with 2:1 block. The other has paroxysmal supraventricular tachycardia (PSVT) due to atrioventricular nodal reentrant tachycardia (AVNRT). Can you tell which is which?

Case 26

 

Case 27

 

 

SILENT HISTORY

A 75-year-old man has an ECG before undergoing cataract surgery. He denies previous cardiac problems. What does his ECG show?

Case 28

 

 

THREE PATIENTS WITH RECURRENT SYNCOPE

The following three patients (Cases 29-31) had recurrent episodes of fainting. Can you diagnose the cause in each case?

Case 29 21-year-old woman on no medications with normal serum electrolyte values

 

Case 30 37-year-old man

 

Case 31 75-year-old woman

 

 

HEARTBURN

This 52-year-old man has indigestion, nausea, and an irregular pulse. What is the rhythm? What is the underlying problem?

Case 32

 

 

HIDDEN P WAVE “ST-ORIES”

Can you diagnose these two arrhythmias?

Case 33

 

Case 34

 

 

MYOCARDIAL INFARCTION SIMULATOR

This 46-year-old man has chest pain and dyspnea. Initially, he was thought to have had a myocardial infarction. What alternative life-threatening diagnosis would account for all these findings?

Case 35

 

 

IRREGULAR BEHAVIOR

The following highly irregular rhythms are often confused. What is the arrhythmia in each case?

Case 36

 

Case 37

 

 

QUICK CHANGES

These two rhythm strips show underlying sinus rhythm with abrupt changes in cardiac electrical activity and intermittent wide QRS complexes. What are the diagnoses?

Case 38

 

Case 39

 

 

MISSING BIFOCALS

A middle-aged cardiologist left his bifocals at home and missed the following diagnosis. (Clue: see arrow.)

Case 40

 

 

LONG AND SHORT OF IT

Both of these patients have mental status changes. Can you diagnose the cause from the ECG alone? (Clue: The key to their treatable diagnoses relates to the beginning of the ST segment.)

Case 41 30-year-old woman

 

Case 42 65-year-old man

 

 

PACEMAKER PLUS

This 78-year-old man has a VVI pacemaker for complete heart block. He comes into your office with shortness of breath and evidence of pulmonary edema. In addition to the expected pacemaker pattern, what does his ECG show?

Case 43

 

 

ECG/CORONARY ARTERIOGRAM MATCHUP

Which ECG (A to D) goes best with which story for these four middle-aged men?

Case 44 This man had chest pain 3 days ago. His creatine kinase level is now normal. He has an occluded large left circumflex coronary artery and a severe inferoposterolateral wall motion abnormality.

Case 45 This man has had chest pain for the past 4 hours. His creatine kinase level is 800 U/L (normal: less than 200 U/L). He has three-vessel coronary disease with 80% to 90% proximal stenoses and anterior wall hypokinesis.

Case 46 This man had chest pain 1 month ago, but his creatine kinase level is now normal. Currently, he is complaining of dyspnea. He has an occluded proximal left anterior descending coronary artery with an anterior wall aneurysm.

Case 47 This man has had chest pain for 12 hours with a normal creatine kinase level. His coronary arteries and ventricular wall motion are normal.

 

 

 

 

 

CALCULATION LEADS TO DIAGNOSIS

A 40-year-old woman complains about feeling weak. She is not taking any medication. Based on the ECG, what laboratory values do you want checked?

Case 48

 

 

INTEREST-PIQUING T WAVES

What underlying condition explains all findings? Additive clues: QRS voltage, P waves, and QTc.

Case 49

 

 

FITTING FINALE

Case 50