In the electrocardiogram, the R wave represents the process of ventricular repolarization. A poor R wave rise indicates low ventricular voltage, which can occur for various reasons, most commonly in anterior or anterior-interval wall infarcts of small size, because the infarcted myocardium will be acutely injured and conduction block will occur in the injured area, resulting in a poor R wave rise. Poor R-wave rise can be detected in both new anterior wall anterior interval wall infarcts and old infarcts. In addition, myocarditis can also show poor R-wave rise because the damaged myocardium can become hypertrophic or damaged, and conduction block can occur in the area of injury, which can also cause poor R-wave rise. Other diseases, including hypertension, pneumothorax, pulmonary heart disease, pleurisy, etc., may also cause temporary R-wave dyskinesia.