Special Types of Angina and Treatment of Acute Myocardial Infarction: Guidelines for Interventional Therapy, Stenting, and Cardiopulmonary Resuscitation

17. Is it okay to not rush into treatment for newly diagnosed exertional angina? Newly diagnosed exertional angina refers to the onset of exertional angina in a normal person within the past month, or angina attacks that have occurred in the past few months but have recently recurred. The cause of newly diagnosed exertional angina is that atherosclerotic plaques in the coronary arteries change from a stable to an unstable state. That is, stable plaques may rupture, bleed, form thrombi, or induce vasospasm, leading to further narrowing of the coronary arteries and causing pain attacks.

18. What are the characteristics of worsening exertional angina? Worsening exertional angina is characterized by a recent (within 1 month) worsening of stable angina symptoms, with a progressive deterioration of the condition. Angina can occur even with mild activity or at rest, including supine angina. Most patients have no obvious triggers; angina can occur with less activity than before and the frequency of attacks has increased; it can occur at rest or during sleep, especially during morning routine activities; the duration is prolonged and rest does not completely relieve it; sensitivity to nitroglycerin is decreased; it worsens within several days and is a precursor to myocardial infarction. During an attack, the patient may appear anxious, pale, and sweating; heart rate and blood pressure may be elevated.

19. What is variant angina? Variant angina differs from, and may even be the opposite of, typical angina in its pain characteristics, causes, and electrocardiogram (ECG) findings. It is not caused by unstable atherosclerotic plaques, but rather by coronary artery spasm, leading to a rapid reduction in coronary blood supply. This causes symptoms to appear even without exertion or emotional stress, often occurring during sleep in the middle of the night or early morning. The pain is prolonged, lasting from tens of seconds to 20-30 minutes, and is extremely severe. During an attack, the ECG shows transient ST-segment elevation.

20. What is angina pectoris? Angina pectoris occurs when lying flat, requiring the patient to sit up, and in severe cases, even stand. Some patients only experience it at night when lying flat, while others experience it both day and night, usually 1-3 hours after lying down, with relatively stable pain. Exertional angina is severe and lasts a long time. These patients are prone to myocardial infarction.

21. What to do about postprandial angina? Postprandial angina is angina that occurs at rest after a meal. It usually occurs 20-30 minutes after a meal, but in those who eat a high-fat diet, angina may occur 3-5 hours after a meal. Postprandial angina is often a sign of severe coronary heart disease and should be treated as unstable angina.

22. How to treat mixed angina? Mixed angina refers to pain that occurs not only under obvious triggers such as exertion or emotional excitement, but also during rest and sleep. That is, the same patient experiences both exertional angina and variant angina. Treatment should address both types. Routine treatment includes aspirin to inhibit platelet aggregation. Nitroglycerin and calcium channel blockers are also commonly used.

23. What are the manifestations of acute myocardial infarction? When certain sudden factors (such as overeating or emotional excitement) induce acute interruption of blood supply, causing myocardial ischemia and necrosis due to prolonged lack of blood and oxygen supply, it is called acute myocardial infarction. The following symptoms may be present: (1) Pain. This is the first symptom. The location and nature of the pain are the same as angina pectoris. Rest and nitroglycerin tablets are often not relieved. Patients are often restless, sweating, fearful, or have a feeling of impending death. (2) Systemic symptoms. These include fever, tachycardia, leukocytosis, and increased erythrocyte sedimentation rate. (3) Gastrointestinal symptoms. These may be accompanied by frequent nausea, vomiting, and upper abdominal distension and pain. (4) Arrhythmia. This occurs in 75% to 95% of patients and usually within 1 to 2 days after onset. (5) Hypotension and shock. (6) Heart failure. This is mainly acute left ventricular failure.

24. What to do during an acute attack of coronary heart disease: When experiencing coronary heart disease pain, patients should immediately stop their current activity and take a nitroglycerin tablet sublingually. If the symptoms do not improve, another tablet can be taken. If there is still no significant relief after 10-20 minutes, the patient should be taken to the hospital immediately. If the patient experiences loss of consciousness or cardiac arrest, chest compressions should be performed on the spot. The procedure is as follows: Have the patient lie supine on a hard surface. Kneel beside the patient, place the heels of both hands on the lower third of the sternum with arms straight, and press vertically downwards on the sternum, causing it to indent about 3 cm. Then relax. Repeat 60-70 times per minute.

25. What to do if angina recurs soon after a myocardial infarction? Angina that recurs within one month after an acute myocardial infarction is called post-infarction angina, which usually occurs within 10 days. Post-infarction angina is prone to re-infarction and has a high mortality rate. Therefore, if medical treatment is unsatisfactory, coronary angiography should be performed promptly to choose from percutaneous transluminal coronary angioplasty, stent implantation, or coronary artery bypass grafting.

26. What is percutaneous transluminal coronary angioplasty (PTCA)? PCA is a treatment method that has been developed in recent years and has achieved very good results. After coronary angiography confirms severe coronary artery stenosis, PCA is performed as needed. This involves inserting a catheter with a balloon at its tip into the lesion site of the coronary artery via the femoral or radial artery under X-ray fluoroscopy. The balloon is then inflated to dilate the stenotic lesion, increasing the diameter of the coronary artery lumen, thereby improving myocardial blood supply and relieving symptoms.

27. What is stent implantation? After balloon dilation of a stenotic lesion, 30%–50% of lesions will restenosis. Some patients may even experience acute coronary artery occlusion, leading to acute myocardial infarction or death. Therefore, after the blood vessel is dilated, a coronary stent is needed to open the lesion. Stent implantation aims to reduce the collapse or acute occlusion of the coronary artery after plaque tearing, increase surgical safety, and reduce restenosis. After an acute myocardial infarction, early, complete, and continuous opening of the blocked blood vessel can save the dying myocardium. After interventional treatment, medication is still required. Its main purposes are: to correct risk factors, regulate blood lipids, reverse myocardial hypertrophy, lower blood pressure, stabilize atherosclerotic plaques, inhibit platelet aggregation, and prevent thrombosis.