ECG

During each cardiac cycle, the heart is excited by the pacemaker, the atria, and the ventricle. With the changes in bioelectricity, various forms of potential change patterns (ECG) are extracted from the body surface by electrocardiograph. An electrocardiogram is an objective indicator of the process of cardiac excitability, transmission, and recovery. Electrocardiogram is the earliest, most commonly used and most basic diagnostic method for the diagnosis of coronary heart disease. Basic Information Specialist classification: cardiovascular examination classification: electrocardiogram Applicable gender: whether men and women apply fasting: not fasting Tips: Listen to the doctor's arrangements. Normal value 1. Each small square on the ECG drawing has a horizontal grid of 0.04s and a vertical grid of 0.lmV. 2, heart rate sinus rhythm, normal between 60 ~ 100bpm *, more than 100bpm for sinus tachycardia, less than 60bpm for sinus bradycardia. Below or above normal frequency within a certain range, as well as mild sinus arrhythmia, are normal range of heart rhythms. 3, heart rate healthy people most of the time for normal sinus rhythm, occasional premature beats (see Chapter 12) is not abnormal. 4, P wave in the limb lead in addition to aVR is inverted, the remaining lead is mostly upright, or low level. In the chest wall lead V1-6 is not enough to stand upright. 5. The PR interval starts from the P wave and starts at the QRS complex. The normal range is 0.12 to 20 s. 6. The QRS complex is a narrow, morphological (qR, R, Rs, rS, or qRs) group with a time range of 006 to 010 s. 7. The ST segment is a segment from the beginning of the QRS group to the beginning of the _r wave. The normal form is shallow and shallow with the uprightness of the T wave. Parallel depression of sT segment or depression of oblique F is abnormal. Mild elevation can be seen in normal people, and should be combined with clinical conditions to judge whether it is normal or not. 8, T wave; except that the aVR lead is inverted, the rest should be erect when the R wave is higher than 05mV. (For example, the leads in I and II should be erect, the aVR should be inverted, and the chest lead should be erect from V4-6). 9. After crossing the U wave, the small crossing is easy to see in V2-3. Normally it should be erect, and other leads may not be obvious. 10. The QT interval starts from the qRS wave to the end of the T wave. The QT interval varies slightly with heart rate, but the extension of QT interval and heart rate is more important. Abnormal shortening is mostly caused by drug or electrolyte imbalance. Clinical significance The electrocardiogram mainly reflects the electrical activity of the heart, so it has a positive value for the diagnosis and analysis of various arrhythmia and conduction block. Characteristic ECG changes and evolution are reliable and practical methods for diagnosing myocardial infarction. Myocardial damage, insufficient blood supply, drug and electrolyte disturbances can cause certain ECG changes, which can help diagnose. Electrocardiogram is of great significance for the diagnosis of coronary heart disease. Coronary artery insufficiency due to myocardial ischemia caused by coronary arteriosclerosis, its electrocardiogram is characterized by T wave inversion, ST segment decline greater than 0.05 mV, sometimes ST segment elevation greater than 0.1 mV in the precordial pain episode, called variant angina . Acute myocardial infarction caused myocardial necrosis due to sudden blockage of the coronary lumen. The ECG features are as follows: ischemic change T wave inversion. The damage-changing ST-segment elevation forms a unidirectional curve with the erect T-wave. Pathological Q waves appear in necrotic changes. Precautions Listen to the doctor's arrangements. Inspection process Electrocardiograms have developed rapidly in both theory and practice due to continuous improvements in assay instruments and assays and in combination with electrophysiological studies of individual cardiomyocytes. Normal people's electrocardiogram generally has 5 waves, which are P, Q, R, S, and T waves. The P wave represents atrial depolarization, the QRS complex represents ventricular depolarization, the T wave represents ventricular repolarization, and the PQ interval (from the beginning of the P wave to the beginning of the QRS complex) represents the time of excitation conduction between the atrioventricular. Not suitable for the crowd Generally there are no people who are not suitable. Adverse reactions and risks Generally no adverse reactions.