Clinical discrimination of angina pectoris
The performance of patients with angina pectoris is often atypical. Therefore, caution should be taken when judging whether chest discomfort or pain is angina pectoris. In recent years, foreign scholars have also stressed that the word angina pectoris does not fully represent pain. Patients’ feelings of myocardial ischemia and hypoxia may be other feelings other than pain, so they may deny feeling pain. The following aspects are helpful to distinguish angina pectoris clinically.
（1） The nature of angina pectoris should be compression, suffocation and heavy stuffy pain, rather than knife cutting sharp pain or scratch pain, short acupuncture or electric shock pain, or chest tightness day and night. In fact, it is not “colic”. In a few patients, it can be burning, tension or shortness of breath, accompanied by a sense of pressing above the throat or trachea. Pain or discomfort is mild at first, gradually intensified, and then gradually disappeared. It is rarely affected by change or deep breathing.
（2） Site pain or discomfort is often located outside the sternum or adjacent to it, and can also occur at any level from the upper abdomen to the pharynx, but rarely above the pharynx. Sometimes it can be located in the left shoulder or left arm, and occasionally it can be accompanied by the right arm, lower jaw, lower cervical spine, upper thoracic vertebra, left interscapular or suprascapular area. However, it is rarely located in the left armpit or left chest. For the distribution range of pain or discomfort, patients often need to use the whole palm or fist to indicate, and rarely use the tip of one finger to indicate.
（3） The time limit is 1-15 minutes, most of which are 3-5 minutes, occasionally up to 30 minutes (except for intermediate syndrome). The pain lasts only a few seconds or the discomfort (mostly stuffy) lasts all day or several days, which is not like angina pectoris.
（4） Physical exertion was the main inducing factor, followed by emotional excitement. Climbing stairs, brisk walking on the flat ground, walking after a full meal, walking against the wind, and even the slight movement of defecating hard or raising the arm over the head, exposure to the cold environment, cold drinks, pain in other parts of the body, as well as emotional changes such as terror, tension, anger and trouble can be induced. The pain threshold in the morning is low, and mild labor such as brushing teeth, shaving and walking can cause the attack; If the pain threshold increases in the morning and afternoon, heavier labor may not be induced. Discomfort that occurs after physical activity rather than at the time of physical activity is not like angina pectoris. Physical activity plus emotional activity is more likely to be induced. Spontaneous angina pectoris can occur without any obvious inducement.
（5） Effect of glycerol
If sublingual glycerin tablets are effective, angina pectoris should be relieved within 1 ~ 2 minutes (or 5 minutes, taking into account that the patient may not estimate the time accurately). Glycerol may not be effective for recumbent angina pectoris. When evaluating the effect of glycerol, we should also pay attention to whether the drug used by the patient has failed or is close to failure.