Prolonged Arterial Occlusion Worksheets

Home » MEDCLIN530 » EKG » 12-Lead EKG Confidence » V. Ischemic Disorders: EKG Changes Related to Ischemia and Myocardial Infarction » 15. Prolonged Arterial Occlusion: Q Waves and Equivalents » Prolonged Arterial Occlusion Worksheets
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These worksheets are for self-study only. Answers will not be evaluated.

Instructions for Chapter 15 Worksheets

  1. Complete basic measurements.
  2. Note if inverted T waves or ST segment depression is present. Note the presence of Q waves or Q wave equivalents as described in columns A, B, and E in Figure 15.12. Diagnose Q wave infarction according to the patterns in Table 15.2. Next, attempt to estimate timing of the infarction according to the T and ST abnormalities by using Table 15.1. Lastly, interpret T or ST abnormality according to the three Rules of the T Waves.
  3. Provide an interpretation.

 

 

Clinically-Based Critical Thinking: Interpretation

Diagnose inferior infarction based on the Q waves in the inferior leads. There is a wide R wave in leads V1 and V2, which is equivalent to a posterior wall Q wave. The inverted T waves in the inferior leads suggest that the infarction may have been recent. However if this is the only EKG, First Rule of the T Waves is in effect. The T inversion may be due to the previous Q wave infarction, but it may also be a new event! More information is necessary.

Worksheet 15.1

Complete the basic measurements, evaluation, and interpretation for the EKG below.

Parameter Measurement Interpretation
HR    
Rhythm    
PR    
QRS    
QT    
QTc    
P direction    
QRS direction    
Abnormal parameter If present, note the leads or location
Inverted T waves  
ST depression  
ST elevation  
Q waves or equivalents  
HR 100. Sinus Rhythm. PR 0.12, normal. QRS 0.08, normal. QT and QTc normal. P direction normal. QRS upward, but not enough for LAHB. T and ST segments are normal. The initial QRS is abnormal in V1 through V4, consistent with Q wave infarction. Since the ST and T segments are normal, the Q wave infarction may be old. The HR of 100 suggests the possibility of CHF secondary to LV systolic dysfunction after the MI.

Worksheet 15.2

Complete the basic measurements, evaluation, and interpretation for the EKG below.

Parameter Measurement Interpretation
HR    
Rhythm    
PR    
QRS    
QT    
QTc    
P direction    
QRS direction    
Abnormal parameter If present, note the leads or location
Inverted T waves  
ST depression  
ST elevation  
Q waves or equivalents  

HR 79, sinus rhythm. PR 0.12 seconds. QRS 0.09. QT 0.36. P direction normal. QRS direction normal. Significant Q waves in leads II, III, and AVF. This indicates Q wave infarction of the inferior wall. The tall wide R wave in lead V2 is equivalent to a posterior wall Q wave. As to timing, the ST segment depression means the Q wave infarction may have been recent. If this is the only EKG, the First Rule of the T Waves still applies, and the ST depression may be due to the old Q wave infarction, or a new episode of ischemia or infarction. More information is necessary.

Worksheet 15.3

Complete the basic measurements, evaluation and interpretation for the EKG below.

Parameter Measurement Interpretation
HR    
Rhythm    
PR    
QRS    
QT    
QTc    
P direction    
QRS direction    
Abnormal parameter If present, note the leads or location
Inverted T waves  
ST depression  
ST elevation  
Q waves or equivalents  

HR 94. Sinus rhythm. Significant Q waves are present in leads V1 through V4. The presence of ST elevation in V1 through V3 takes precedence over everything else (STEMI) and suggests the acuteness of the infarction.