Simplified Explanation of ECG Changes in Heart Attack

Simplified Explanation of ECG Changes in Heart Attack


Simplified Explanation of ECG Changes in Heart Attack

Hope you enjoyed my previous videos on ‘What is ECG’ and ‘Errors in ECG Recording’. Some of you asked how ECG becomes abnormal in a heart attack. Here is a very simplified explantation.
As mentioned in my previous video, ECG has mainly a P wave representing activity of the upper chambers and a QRS complex and T wave representing the activity of the lower chambers.
In a major heart attack, the electrical activity of the heart muscle immediately below the recording electrode disappears. So, the positive part of the QRS complex disappears and a negative wave appears. T wave also gets inverted usually, though the P wave generated from the upper chambers is usually spared.


Content

0.59 -> Hope you enjoyed my previous videos on ‘What is ECG’ and ‘Errors in ECG Recording’.
8.53 -> Some of you asked how ECG becomes abnormal in a heart attack. Here is a very simplified
14.74 -> explantation. As mentioned in my previous video, ECG has
20.539 -> mainly a P wave representing activity of the upper chambers and a QRS complex and T wave
28.09 -> representing the activity of the lower chambers. In a major heart attack, the electrical activity
35.3 -> of the heart muscle immediately below the recording electrode disappears. So, the positive
42.17 -> part of the QRS complex disappears and a negative wave appears. T wave also gets inverted usually,
51.45 -> though the P wave generated from the upper chambers is usually spared.
57.08 -> Of course, this is a highly simplified explanation of what is seen in an ECG after the heart
64.839 -> attack is fully established. Picking up a heart attack earlier requires more expertise.
72.899 -> Expertise is also needed to rule out causes other than heart attack which can sometimes
78.709 -> cause ECG abnormalities and normal variations. Many of the modern computerized ECG machines
86.329 -> have built in software which can detect a heart attack in its early stage and display
93.439 -> the interpretation in the ECG printout. But errors can occur and always needs a careful
100.759 -> interpretation by the medical personnel correlating with symptoms and signs in the person.

Source: https://www.youtube.com/watch?v=wn3cOA3pvgw