Author Question: Which of the following is the most characteristic electrocardiographic finding in myocardial ... (Read 38 times)

fasfsadfdsfa · **on:** Jul 16, 2018

Which of the following is the most characteristic electrocardiographi c finding in myocardial in-farction?

a. T wave inversion c. ST segment depres-sion
b. ST segment eleva-tion d. Down-ward-deflected Q waves

Question 2

What is the heart rate depicted on the following electrocardiogram?

a. 60 c. 100
b. 80 d. 120

bhavsar · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: D
When cardiac tissue fed by the left anterior descending and circumflex branches of the left cor-onary artery infarct, Q waves become abnormal most noticeably on the left precordial leads. As a result, the Q waves deflect downward instead of upward because of a lack of counterbalancing electrical forces on the affected side.

Answer to Question 2

ANS: B
Isolating 3 seconds out of the strip shows that there are 4 cardiac cycles in the 3-second period. Multiply 4 by 20. The heart rate is 80 beats/min.