Which is not detected usually by ECG ?

Options

A. Arrhythmia
B. Myocardial infarction
C. Heart block
D. Valvular defects

Answer

To determine which condition is not usually detected by an electrocardiogram (ECG), we can analyze the options provided: erythema, myocardial infarction, heart block, and valvular defects.

### Step-by-Step Solution:

1. **Understanding ECG**: An electrocardiogram (ECG) is a test that records the electrical activity of the heart over a period of time. It provides information about the heart's rhythm, the size and position of the heart chambers, and any damage to the heart.

2. **Analyzing the Options**:
- **Erythema**: This is a condition characterized by redness of the skin, which is not related to the electrical activity of the heart. Therefore, it would not be detected by an ECG.
- **Myocardial Infarction**: Commonly known as a heart attack, this condition can lead to changes in the heart's electrical signals, which can be detected by an ECG.
- **Heart Block**: This condition involves a delay or blockage in the electrical signals that control the heartbeat. It can also be detected through an ECG.
- **Valvular Defects**: These defects pertain to the heart valves and their function, which is not directly related to the electrical activity of the heart. While some indirect effects may be observed, valvular defects are primarily assessed through echocardiography rather than ECG.

3. **Conclusion**: Among the options, **valvular defects** are not usually detected by an ECG. They require other diagnostic methods, such as an echocardiogram.

### Final Answer:
**Valvular defects** are not detected usually by ECG.

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