心絞痛和心肌梗塞的區別, 應急措施...

1.
“心絞痛”(Angina) 和“心肌梗塞”(Myocardial infarction = MI)是冠心病 (Coronary artery disease)常見的臨床類型;

Angina (low oxygen to heart tissues) = no dead heart tissues;  Myocardial infarction = dead heart tissue present;

2.
“心絞痛”即“狹心症". 表現為胸骨後部的疼痛或壓縮感覺，可放射到左肩或左臂，由暫時性心肌缺血所引起。在飯後、情緒緊張或勞動時發生的稱“勞累性心絞痛”；發生在靜息時稱“自發性心絞痛”。一般自發性心絞痛比勞累性嚴重; 心絞痛多見於冠狀動脈性心髒病或主動脈瓣關閉不全; 

應急:  
休息或服硝酸甘油後可緩解 (舌下含服，5分鍾一次,  may give up to 三次 to attempt to relieve angina pain); 

應急Medicine:
MOAN ( Morphrine, Nitro, Oxygen, Aspirin);

Angina is chest discomfort that occurs when there is decreased blood oxygen supply to an area of the heart muscle. In most cases, the lack of blood supply is due to a narrowing of the coronary arteries as a result of arteriosclerosis;

Angina is usually felt as:  pressure,  heaviness, tightening, squeezing, or aching across the chest, particularly behind the breastbone.

This pain often radiates to the neck, jaw, arms, back, or even the teeth.  Patients may also suffer:  indigestion,   heartburn,   weakness,  sweating,  nausea, cramping, and  shortness of breath.

Angina usually occurs during exertion, severe emotional stress, or after a heavy meal, when the heart muscle demands more blood oxygen than the narrowed coronary arteries can deliver. Angina typically lasts from 1 to 15 minutes and is relieved by rest or by placing a nitroglycerin tablet under the tongue, which relaxes the blood vessels and lowers blood pressure. Both rest and nitroglycerin decrease the heart muscles demand for oxygen, relieving angina.

Angina is classified in one of two types: 1) stable angina or 2) unstable angina.

Stable angina

Stable angina is the most common type of angina, and what most people mean when they refer to angina. People with stable angina have angina symptoms on a regular basis and the symptoms are somewhat predictable (for example, walking up a flight of steps causes chest pain). For most patients, symptoms occur during exertion and commonly last less than five minutes. They are relieved by rest or medication, such as nitroglycerin under the tongue. Stable angina is one of many causes of chronic chest pain.

Unstable angina

Unstable angina is less common but more serious. The symptoms are more severe and less predictable than the pattern of stable angina. Pain is more frequent, lasts longer, occurs at rest, and is not relieved by nitroglycerin under the tongue (or the patient needs to use more nitroglycerin than usual). Unstable angina is not the same as a heart attack, but warrants an immediate visit to your physician or hospital emergency department as further cardiac testing is urgently needed. Unstable angina is often a precursor to a heart
 

Angina treatment options include:
1. rest,
2. medications (nitroglycerin,  beta blockers, Aspirin, or  calcium channel blockers, ),
3. percutaneous coronary intervention (stenting or transluminal coronary angioplasty (PTCA), or
4. coronary artery bypass graft surgery (CABG).

3.
“心肌梗塞”又稱“心肌梗死”，由冠狀動脈粥樣硬化，繼以血栓形成，冠狀動脈的分枝堵塞，因而一部分心肌失去血液供應而壞死。發病時有劇烈而持久的類似心絞痛的前胸痛, 心悸, 氣喘, 脈搏微弱, 血壓降低等症狀。硝酸甘油含片不能使疼痛緩解，並可伴有大汗和四肢厥冷等症狀;

如果出現心肌梗塞的先兆症狀，千萬不要驚慌，首先病人應立刻臥床，保持安靜，避免精神過度緊張，舌下含服硝酸甘油，立即 call 911;   同時做好送往ER的準備, 交通工具必須平穩舒適;  病人應避免走動，運送途中可持續或間斷使用硝酸甘油等擴冠藥;

應急: 
休息保持安靜;  Aspirin (160mg - 325mg, PO);  舌下含服Nitro, 5分鍾一次, 三次;  call 911 ;  

Medicine:  
BATH ( Beta inhibiytor, ACE inhibitor, Thrombolytic, Heparin);


A heart attack (also known as a myocardial infarction or MI) is the death of heart muscle from the sudden blockage of a coronary artery by a blood clot. Coronary arteries are blood vessels that supply the heart muscle with blood and oxygen. Blockage of a coronary artery deprives the heart muscle of blood and oxygen, causing injury to the heart muscle. Injury to the heart muscle causes chest pain and chest pressure sensation. If blood flow is not restored to the heart muscle within 20 to 40 minutes, irreversible death of the heart muscle will begin to occur. Muscle continues to die for six to eight hours at which time the heart attack usually is "complete." The dead heart muscle is eventually replaced by scar tissue.

What causes a heart attack?    Atherosclerosis!!!   Atherosclerosis is a gradual process by which plaques (collections) of cholesterol are deposited in the walls of arteries. Cholesterol plaques cause hardening of the arterial walls and narrowing of the inner channel (lumen) of the artery. Arteries that are narrowed by atherosclerosis cannot deliver enough blood to maintain normal function of the parts of the body they supply.

Coronary atherosclerosis (or coronary artery disease) refers to the atherosclerosis that causes hardening and narrowing of the coronary arteries. Diseases caused by the reduced blood supply to the heart muscle from coronary atherosclerosis are called coronary heart diseases (CHD). Coronary heart diseases include heart attacks, sudden unexpected death, chest pain (angina),  abnormal heart rhythms, and heart failure due to weakening of the heart muscle.

MI victims may experience a variety of symptoms including:  
1. Pain, fullness, and/or squeezing sensation of the chest;
2. Jaw pain, toothache, headache; 
3. Shortness of breath; 
4. Nausea, vomiting, and/or general epigastric (upper middle abdomen) discomfort
5. Sweating
6. Heartburn and/or indigestion
7. Arm pain (more commonly the left arm, but may be either arm); Upper back pain
8. No symptoms (Approximately one quarter of all heart attacks are silent, without chest pain or new symptoms. Silent heart attacks are especially common among patients with diabetes mellitus.)


MI Treatment:

1. Thrombolytic (fibrinolytic or clot dissolving) with in 6 hours therapy has been shown to reduce death from heart attacks similarly in men and women; however, the complication of strokes from the thrombolytic therapy may be slightly higher in women than in men.

2.  Medical treatment for heart attacks may also  include:  antiplatelet, anticoagulant, and clot dissolving drugs as well as angiotensin converting enzyme (ACE) inhibitors, beta blockers, and oxygen;

3. Interventional treatment for heart attacks may include coronary angiography with percutaneous transluminal coronary angioplasty (PTCA), coronary artery stents, and coronary artery bypass grafting (CABG).

4.
心絞痛和心肌梗塞均屬於Coronary artery disease;  But 心絞痛和心肌梗塞在治療和預後方麵不同;

（1）心絞痛的疼痛性質多為壓榨性或窒息性，常因勞累, 受寒, 激動等因素所誘發。發作時間較短，一般不超過15分鍾。發作後服用硝酸甘油有明顯好轉。一般無氣喘、肺水腫症狀；血壓變化不大，所以無休克現象，也無發熱。化驗檢查：白細胞計數正常、血沉可正常活略快、無血清酶學變化; 心電圖可無變化或有暫時性改變;

（2）心肌梗塞的疼痛性質與心絞痛類似，但更為劇烈，可無誘發因素發作。發作時間長，可從數小時到1～2天。服用硝酸甘油不能緩解。常伴有氣喘和肺水腫，血壓往往下降而出現休克。因有心肌壞死。所以常有發熱。化驗檢查：白細胞計數升高、血沉顯著增快、有血沉清酶學變化，心電圖可呈進行性特殊改變。