I. Clinical manifestations of angina pectoris
Angina is caused by myocardial ischemia, which is the result of insufficient blood (oxygen) supply to maintain myocardial metabolic needs. Various factors that reduce myocardial blood (oxygen) supply (such as intravascular thrombosis, vascular spasm) and increase oxygen consumption (such as exercise, increased heart rate) can induce angina.
Sometimes or in some patients, myocardial ischemia does not cause chest pain, such as in some elderly patients or diabetic patients; some patients even do not know or cannot recall when they have suffered a myocardial infarction and only discover it later on an electrocardiogram.
(I) Location
Angina pectoris usually presents as chest pain, most often in the retrosternal or precordial region, but can also occur anywhere between the diaphragm and the lower jaw. The pain is as wide as the size of a hand fist. The most common site of radiation is the medial aspect of the left upper arm. Pain may also radiate to the neck, scapular region, jaw, or pharynx.
(ii) Contributing factors
Angina pectoris is often triggered by physical activity or emotional excitement, and usually occurs during or immediately after stopping activity. In addition, chest pain can also be triggered by satiety, bowel movements, and cold air. Some patients have chest pain when they wake up early in the morning or with light activity, while the same amount of activity during the day does not cause chest pain. Other patients have angina in the recumbent position. In patients with severe coronary artery disease, angina may also occur at rest, but these patients still have typical post-activity chest pain.
(iii) Nature
The nature of the pain is often pressure-like, with the patient often complaining of a feeling of pressure, squeezing or chest tightness. The pain is not pins and needles or tearing, nor is it throbbing, and is not related to breathing.
(iv) Duration
A typical angina attack is often within 3-5 minutes and rarely exceeds 10 minutes. The pain is completely relieved after the attack has stopped.
(E) Relief mode
The angina is relieved by rest. During an attack, the patient often stops the original activity until the attack stops. The pain is often relieved within 1-2 minutes after sublingual administration of nitroglycerin, and usually does not exceed 10 minutes.
In patients with otherwise stable attacks, if the triggering factors for the attack are gradually becoming less obvious or the amount of exercise induced by the attack is becoming less and less, exercise tolerance decreases, the frequency of attacks increases, the severity increases, the duration of attacks is prolonged, nitroglycerin does not easily relieve or spontaneous attacks occur, it often indicates an unstable or severe lesion, which is unstable angina, and should be quickly seen and admitted to the CCU for observation and treatment and further Coronary angiography, based on which balloon dilation (PTCA) or coronary artery bypass grafting is performed.
The nature of chest pain in myocardial infarction is basically similar to angina pectoris, but the pain is more severe, often unbearable and lasts longer, and is not relieved by nitroglycerin, often accompanied by cold sweat and vomiting.
Second, the differential diagnosis of angina pectoris
(A) emotional or mental factors leading to chest discomfort or chest pain
It can also be called cardiac neurosis, mostly seen in young and middle-aged women or menopausal women. In fact, premenopausal women without risk factors (such as family history, hypertension, dyslipidemia and diabetes) rarely develop coronary heart disease. Patients often experience chest discomfort in the form of sharp stabbing or tearing pain, often located near the left breast, sometimes the size of a pinpoint, and lasting for a short period of time; it can also be a constant, dull pain that lasts for hours or even days, unrelated to or not clearly related to activity, or even relieved after activity or mental relaxation. Nitroglycerin may also be “effective”, but mostly after 10 minutes, and the relief is incomplete.
In addition to chest discomfort, patients often complain of weakness, dizziness, poor sleep, muscle throbbing, dyspnea, and other physical discomfort. Some patients can find triggers, both family and possibly social or institutional.
Some patients are afraid to be active or even unable to go to work because of this, while the patient’s age and physical signs do not support having severe coronary artery disease.
The physical examination is mostly normal or not related to the heart. The patient is mostly found to be emotionally unstable, agitated, hypersensitive, or dramatic in performance.
These patients may have ST-segment shift, or T-wave changes. An ECG exercise stress test, or even echocardiography or radioisotope examination should be performed.
Attention should be paid to the patient’s age and gender, psychosocial factors, and the presence of risk factors for coronary heart disease.
(B) Angina pectoris caused by other diseases
1. Hypertrophic obstructive cardiomyopathy
Due to left ventricular outflow tract obstruction, hypertrophic obstructive cardiomyopathy may have angina pectoris, syncope or dyspnea, mostly related to activity, chest pain is aggravated after taking nitroglycerin, systolic murmur can be heard on examination at the left edge of the sternum, which can be identified by cardiac ultrasound.
2. Valvular disease
Angina pectoris can also occur with aortic stenosis or incomplete closure, and echocardiography should be performed. If coronary artery disease is suspected at the same time, coronary angiography should be performed.
3. Other diseases involving the coronary arteries
Such as coronary artery malformation or congenital abnormal development, coronary artery myocardial bridge, coronary arteritis caused by rheumatic disease, coronary artery entrapment or acute aortic entrapment involving coronary artery, coronary artery embolism, syphilitic aortitis causing coronary artery orifice stenosis or occlusion.
4. X syndrome
X syndrome is mostly seen in women, caused by capillary malfunction of the coronary artery system, and is related to coronary artery endothelial dysfunction. The exercise test may be positive, but the prognosis is relatively good if there is no fixed stenosis on coronary angiography or only coronary artery spasm is seen.
(C) Chest pain or chest discomfort caused by non-coronary heart disease
1. Premature beats
Premature beats may be accompanied by chest discomfort or even pain, mostly during inactivity and disappearing or not felt after activity. It should be determined whether the premature beats are benign in nature or accompanied by heart disease, and an ambulatory electrocardiogram, cardiac exercise stress test or echocardiogram should be performed if necessary.
2. Acute pericarditis
Especially in the early stages of pericarditis, there may be pain in the precordial region and retrosternal area, often associated with deep breathing, coughing or position changes, and sometimes painful swallowing. Early pericardial rubbing sounds may be present, and the pericardial rubbing sounds and chest pain often disappear after the appearance of a large amount of effusion. The ST-segment and T-wave changes on the ECG are often located in all leads except the aVR, and the ST short elevation is bowed down, which may be accompanied by signs and symptoms of pericardial compression, as well as systemic symptoms, and the diagnosis can be confirmed by echocardiography.
3. Myocarditis and dilated cardiomyopathy
Symptoms such as chest tightness and dyspnea may be present. Changes in QRS integrated wave, ST segment and T wave can be found on ECG. Attention should be paid to history taking, careful physical examination, observation of ECG evolution, series of myocardial enzymatic tests, and echocardiography and other tests.
4. Right ventricular hypertension
Pulmonary hypertension can cause angina pectoris due to right ventricular ischemia, commonly seen in mitral stenosis with pulmonary hypertension, pulmonary stenosis, etc.
5. Cardiac hyperdynamic syndrome and mitral valve prolapse
Patients often complain of panic, precordial discomfort, fatigue, dyspnea, anxiety and excessive sweating, etc. The effect of b-blockers is good. The ECG can be confused with coronary artery disease, and the exercise test can be false positive.
Mitral valve prolapse can also be accompanied by sympathetic excitation and hyperdynamic state, often with clinical manifestations of neurasthenia, cardiac ultrasound can confirm the diagnosis.
6. Acute aortic coarctation
Aortic coarctation can present with severe chest pain and can also involve the coronary arteries, even with myocardial infarction. The general site of chest pain is high, often tearing-like, peaking at the beginning, and may radiate widely to the back, abdominal lumbar region and legs. There may be abnormal pulsations in the chest, abnormal murmurs due to entrapment may be heard, mismatch of blood pressure in both upper or upper and lower extremities, diminished pulse on one side, and paralysis or hemiparesis in the lower extremities. Involvement of the aortic root may result in aortic valve closure insufficiency.
X-ray chest film, echocardiography or magnetic resonance imaging should be performed promptly, and aortogram should be performed if surgery is considered.
7. Acute pulmonary embolism
Acute massive pulmonary embolism may cause chest pain, unexplained dyspnea, syncope, shock and other manifestations, and the patient may be accompanied by cold sweat, cyanosis or a sense of near death. However, the patient’s physical examination, electrocardiogram and chest X-ray may show acute pulmonary hypertension or acute right heart insufficiency, such as pulmonary P wave, right bundle branch block or more specific SIQIIITIII on the electrocardiogram; the upper vena cava shadow is widened, the right lower pulmonary artery is widened or the pulmonary artery segment is prominent, and the texture of the external and external lung fields is reduced on the chest X-ray. Echocardiography may reveal a weakened right ventricular beat and a leftward shift of the septum. Pulmonary artery pressure may also be estimated based on tricuspid regurgitation. A floating catheter such as an increased central venous pressure and pulmonary artery pressure with a normal pulmonary artery pressure can be distinguished. Pulmonary artery plus coronary artery angiography is necessary.
(D) Thoracic and pulmonary diseases
1) Chest trauma
History should be taken, with chest tenderness, pain related to coughing, deep breathing, posture or certain activities.
2. Costochondritis and intercostal neuralgia
It is a stabbing or burning pain, which can be related to activity, with clear pressure points, sometimes with neurological manifestations, no changes in ECG, and no high cardiac enzymes. Other chest wall pains can be caused by intercostal muscle strain and viral infection. The chest pain is characterized by sharp pain with tenderness, and can be aggravated by coughing and deep breathing.
3. Chest herpes zoster
It can be confused with myocardial ischemic pain before the appearance of herpes. The affected area is characterized by hypersensitivity of the skin with tenderness, and there may be headache, fever and general malaise.
4. Pneumonia
The electrocardiogram may show signs similar to myocardial infarction or myocardial ischemia, but not consistent with the evolution of myocardial infarction or myocardial ischemia, with symptoms such as fever, cough or sputum, and series of myocardial enzymology and X-ray chest film may be distinguished.
5. Spontaneous pneumothorax
Sudden chest pain and dyspnea, chest pain on the side of the occurrence of pneumothorax, drum sound on chest snapping, X-ray chest film can confirm the diagnosis.
6. Mediastinal emphysema
Chest pain and mediastinal twang are the typical manifestations, and subcutaneous emphysema may appear in the neck or upper thorax, and X-ray chest film can confirm the diagnosis.
7. Thoracic outlet syndrome
Thoracic outlet syndrome involves nerves and vascular structures coming out of or passing through the upper edge of the chest cavity and is caused by compression. It is associated with bone or muscle abnormalities, and symptoms tend to appear in the 20s and 40s. It can be associated with occupational activities, poor posture, or neck trauma. Most patients present with upper extremity pain, especially on the ulnar side, which may also radiate to the neck, shoulder, scapular area or axilla, and rarely the pain is located in the chest wall. An electrocardiogram and cardiac enzymology should be checked in those with chest pain along with a careful physical examination.
8. Pleurisy
Typical pleuritic chest pain, associated with breathing and coughing, can be accompanied by systemic symptoms such as fever or occur after myocardial injury, and large accumulation of fluid can cause dyspnea.
(E) Gastrointestinal disorders of upper abdomen and chest discomfort
1. Reflux esophagitis and esophageal hiatal hernia
Reflux esophagitis is an inflammation of the esophageal mucosa caused by reflux of gastric contents into the esophagus, which can be complicated by esophageal peptic ulcer or stricture. The most common symptoms are retrosternal chest pain, burning sensation, pain in the throat and “indigestion”, associated with eating or changes in position, and may include acid reflux, regurgitation of bitter liquids or stomach contents, which may be relieved by antacids.
There is no clear relationship between esophageal hiatal hernia and reflux esophagitis, and thoraco-abdominal radiography can assist in the diagnosis.
2. Esophageal perforation or rupture
The mortality rate is very high, mostly related to instrumentation or trauma, and other causes such as necrosis by compression of esophageal cancer. Automatic rupture of esophagus mostly occurs due to dry vomiting or vomiting after a full meal, when pain under the sword appears and radiates to the scapular region. Patients may present with dyspnea, sweating and cyanosis, followed by pallor, tachycardia, shock and mediastinal emphysema.
A chest x-ray may reveal a mediastinal emphysema and pleural effusion, and a barium swallow may identify the site of rupture.
3. Esophageal spasm and esophageal cardia loss retardation
Pain and dysphagia are the main manifestations, nitrates are effective, swallowing is often the trigger of chest pain, especially into cold food, can radiate to the back, neck and jaw, each time lasts for several minutes or hours, activity does not increase the pain, but can be related to emotions.
Physical examination is mostly abnormal, and barium swallow and manometer examination can help to make the diagnosis.
4. Acute abdominal disease
Such as peptic ulcer or perforation, pancreatitis, cholangitis, cholecystitis and cholelithiasis. The epigastric pain present in acute abdomen can be confused with the pain or discomfort radiating from acute myocardial infarction to the upper abdomen, and severe shock can occur.
Abdominal pressure pain and rebound pain, abdominal ultrasound, chest and abdominal X-ray can help in diagnosis, along with electrocardiogram and series of cardiac enzymology.
(F) Other diseases
Other diseases with ECG ST-T changes, such as cerebrovascular accident, abdominal disease, early repolarization syndrome, some need series of ECG and enzymatic examination, and coronary angiography is necessary to exclude myocardial ischemia. Cervical spondylosis can also present with chest and back pain that is mistaken for angina pectoris.