The electrocardiogram (ECG or EKG) is a widely used cardiac examination method used to record the heart's electrical activity for the diagnosis and monitoring of various heart conditions. Despite its widespread clinical application, many misconceptions remain in its actual performance and interpretation. These misconceptions can affect the accuracy of test results and even lead to misdiagnosis or missed diagnoses. This article will discuss common ECG misconceptions and provide corrective measures.
Misconception 1: Improper Electrode Placement
Proper connection of ECG lead devices, such as the ECG lead wires, and subsequent electrode placement during the examination are essential for obtaining an accurate ECG. However, in practice, improper electrode placement is common. For example, misalignment of the chest lead electrodes can cause abnormal changes in the ECG waveform, which can affect subsequent localization diagnosis, such as in some patients with coronary artery disease and myocardial infarction. Large ECG misalignment can lead to inaccurate localization of myocardial infarction or even missed diagnoses. It can also affect the diagnosis of angina pectoris and myocardial ischemia.
Therefore, when performing an ECG, medical personnel must strictly follow standard operating procedures for electrode placement. Chest lead electrodes should be placed on the patient's chest according to standard markings and should not be repositioned arbitrarily. Limb electrodes should be placed on the distal extremities of the patient to ensure good contact with the skin and reduce impedance.
Misconception 2: Neglecting Patient Preparation
Patient preparation before an ECG is also crucial. If the patient is nervous, undergoes the examination immediately after exercise, or is not positioned properly, the ECG results can be affected. Some medical personnel fail to fully inform the patient of the necessary preparations before the examination, which can easily distort the results.
Before the examination, medical personnel should instruct the patient to remain calm, avoid strenuous exercise, and remain supine during the examination. For nervous patients, appropriate reassurance can be provided to ensure they are relaxed during the examination. Avoid performing the examination immediately after a meal or exercise to avoid distorting the results.
Misconception 3: Failure to eliminate environmental interference
Electromagnetic interference in the environment can significantly affect ECG recordings. For example, medical equipment and electrical wiring can generate electromagnetic interference, causing ECG artifacts. If not eliminated, this can mislead doctors.
When performing an ECG, choose a location away from sources of electromagnetic interference and turn off any unnecessary electronic devices nearby. If significant artifacts are detected during the examination, the source of the interference should be promptly identified and addressed to ensure a clear and accurate ECG signal.
Misconception 4: Ignoring the patient's medical history and symptoms
ECG results must be interpreted in conjunction with the patient's medical history and symptoms. Ignoring the patient's overall condition while relying solely on ECG results can lead to misdiagnosis. Some abnormal ECG waveforms may be due to non-cardiac causes, and an ECG alone cannot fully reflect the patient's health.
ECG results should be interpreted comprehensively, taking into account the patient's medical history and symptoms. For example, in patients with a history of heart disease, some minor ECG abnormalities may be clinically significant; whereas in healthy individuals, these abnormalities may simply be physiological variations. In addition, attention should be paid to the patient's subjective symptoms, such as chest pain and shortness of breath, as they serve as important reference points for ECG interpretation.
Misconception 5: Over-reliance on Automatic Analysis Results
Modern ECG machines often have automatic analysis functions, which can quickly provide preliminary results. However, automatic analysis results are for reference only and cannot completely replace the physician's judgment. Over-reliance on machine analysis results without detailed manual review can lead to missed or misdiagnoses.
Although the automatic analysis functions of modern ECG machines are quite advanced, their results should only be used as a guide. Medical staff should manually review each ECG, conducting a comprehensive assessment based on clinical experience and the patient's specific circumstances. In particular, discrepancies between automatic analysis results and clinical symptoms should be treated with caution and, if necessary, further testing should be performed.
In addition to the common operational and analysis errors mentioned above, hospitals and medical institutions should establish a strict ECG quality control system and regularly calibrate and maintain equipment to ensure accuracy and reliability. Furthermore, the ECG examination process should be monitored, and any problems identified should be promptly corrected to ensure the quality of each ECG. The electrocardiogram (ECG) is an important tool for assessing cardiac function. Correct performance and interpretation are crucial for clinical diagnosis. By avoiding common misconceptions and adopting appropriate procedures, medical professionals can improve ECG accuracy and ensure timely and accurate diagnosis and treatment for patients. We hope that this discussion will provide valuable insights for medical professionals and contribute to the advancement and application of ECG technology.