ST và sóng T hyperacute dẫn V1-V4 cho thấy vùng nhồi máu cấp tính trước bức tường. Không sóng Q MI (lựa chọn A) không bao giờ được đưa ra như là một chẩn đoán dựa trên một đọc điện tâm đồ duy nhất bởi vì nó có thể là một làn sóng mới Q-MI chưa phát triển sóng Q. | Answer D Leads II III and aVF show the inferior part of the infarct. A wide QRS with rR in lead V1 shows RBBB. However this is an unusual RBBB because the initial R wave is taller than the R wave in lead V1. This is the clue for true posterior MI. The tall initial R wave in V1 is a pathologic R wave analagous to the pathologic Q wave of an anterior MI. Q9 What is the correct diagnosis of this ECG A. Non-Q wave MI B. Acute anterior MI C. Old inferior MI D. Anterolateral MI E. Posterolateral MI Answer B The marked ST elevation and hyperacute T waves in leads V1-V4 suggest an acute anterior wall infarct. Non-Q wave MI choice A should never be given as a diagnosis based on a single ECG reading because it could be a new Q-wave MI which hasn t yet developed Q waves. 31 Q10 What best describes this ECG tracing E TMi F ank G. V TnrzwJ- L . A. Poor R wave progression B. Diffuse non-specific ST-T wave changes C. Hyperacute anteroseptal MI D. Fully evolved anteroseptal MI E. Left ventricular hypertrophy with strain Answer D This fully evolved anteroseptal MI is diagnosed by the QS waves in V1-2 qrS in V3 and ST-T wave changes. As a side note a monophasic negative QRS complex is referred to as a QS rather than just a Q. 32 Chapter VI I ST-T Segment Q1 Which of the following may cause ST segment depression A. Ischemia B. Hyperventilation C. Ventricular hypertrophy D. Hypokalemia E. All of the above Answer E ST segment abnormalities are very non-specific. The ECG changes must be correlated with clinical data to accurately diagnose any problems. Some other causes of ST segment depression are digoxin mitral valve prolapse CNS disease non-Q wave MI and poor skin-electrode contact. Q2 The ST-T waves in this ECG are A. Primary ST-T wave abnormalities B. Secondary ST-T wave changes C. Non-specific T wave abnormalities D. T wave inversion abnormalities aVR and V1 E. Normal Answer E This is a normal ECG. The normal T wave is asymmetric with the first half moving more slowly less of
