As an important tool for clinical diagnosis, electrocardiogram plays a vital role in the medical field. However, in practical applications, misdiagnosis and missed diagnosis of ECG occur from time to time. This article will analyze the common misdiagnosis and missed diagnosis of electrocardiogram, in order to provide better diagnosis and treatment guidance for doctors and patients.

Misdiagnosis

1. Myocardial infarction misdiagnosed as coronary heart disease

Myocardial infarction and coronary heart disease have similar performances on ECG, which can easily lead to misdiagnosis. The main reasons for this misdiagnosis include:

- Electrocardiogram abnormality is not typical: ECG of some patients with myocardial infarction may not have obvious ST segment elevation or Q wave, leading to misdiagnosis as coronary heart disease;

- Insufficient professional experience: Some doctors have insufficient experience in interpreting ECG and cannot accurately judge the characteristic changes of myocardial infarction;

- Lack of clinical symptoms in patients: patients with myocardial infarction may only present with mild discomfort, which can be easily ignored or mistaken for other diseases.

2. Coronary heart disease misdiagnosed as normal ECG

About 10% to 20% of patients with coronary heart disease may have normal ECG in a quiet state. The main reasons for this misdiagnosis include:

- Microscopic damage cannot be detected early by electrocardiogram: for some coronary heart disease caused by microscopic damage, electrocardiogram may not show obvious abnormalities, and only exercise stress test or other auxiliary examinations can be diagnosed;

- Not severe coronary stenosis: Some patients with coronary heart disease have mild coronary stenosis and relatively normal blood supply to the myocardium, so the electrocardiogram appears normal.

Missed diagnosis

1. Missed arrhythmia

Arrhythmia is one of the important diagnostic indicators of ECG. However, sometimes doctors may miss some potential arrhythmias when interpreting ECG. The main reasons include:

- Inexperienced with rare arrhythmias: Some arrhythmias are rare, and doctors are inexperienced or encounter complicated situations, so it is easy to miss the diagnosis;

- Poor quality of ECG recording: ECG acquisition is affected by restrictive conditions, such as poor electrode paste, signal interference, etc., resulting in arrhythmia that cannot be accurately recorded.

2. Missed diagnosis of left ventricular hypertrophy

Left ventricular hypertrophy is a common pathological change in heart disease, but it is sometimes missed for various reasons. The main reasons include:

- Atypical electrocardiogram: Some patients with left ventricular hypertrophy may have no obvious abnormalities in the electrocardiogram, and it needs to be combined with other examinations to obtain an accurate diagnosis;

- Young patients without typical symptoms: Some young patients may have no obvious symptoms, and the ECG changes are also mild, which are easy to be ignored.

Electrocardiogram plays an important role in clinical diagnosis, but misdiagnosis and missed diagnosis often occur in practice. Doctors should continue to improve their professional level and strengthen the accumulation of experience in ECG interpretation to reduce the risk of misdiagnosis and missed diagnosis. At the same time, patients should cooperate with the doctor's guidance when undergoing ECG examination to ensure the quality of the examination and reduce diagnostic bias.