Acute Coronary Syndromes Flashcards
What are the two processes involved in acute coronary syndromes.
Ischaemia - narrowing of the coronary arteries which leads to a reduction in blood supply (nutrients and oxygen)
Infarction - complete obstruction of the coronary arteries leads to tissue necrosis.
What segment of an ECG is abnormal in a heart attack?
S - T segment
What is a common cause of acute coronary syndromes?
Atherosclerosis
List examples of diseases associated with ischaemia of the coronary arteries.
Angina pectoralis
Peripheral vascular disease (angina of the limbs) comes alongside coronary artery disease.
List examples of diseases associated with infarction of the coronary arteries.
Myocardial infarction
What is angina?
Reversible ischaemia (reduction in blood supply) to the heart muscle.
What causes angina?
Narrowing of the coronary arteries - atherosclerosis.
What are the symptoms of angina?
Crushing chest pain
Pain radiates down arm, up neck and into jaw.
Tightness
What are the types of angina?
Classical - pain on exertion
Unstable - pain occurs at rest
What are the aims of angina/acute coronary syndrome treatment?
To reduce oxygen demands
i.e. reducing preload and afterload via blood pressure.
To increase oxygen delivery
i.e. via angioplasty or coronary artery bypass (CABG)
What are the non-drug therapies for angina/acute coronary syndrome?
Educating the patient so that they live within limits
Modifying lifestyle factors;
Stop smoking
Healthy diet
Exercise programmes to encourage blood flow to the tissues.
What are the drug therapies for angina/acute coronary syndrome?
Nitrates: Dilate veins, and resistance arteries (coronary arteries)
Glyceryltrinitrate - short acting
isosorbide mononitrate - long acting
Aspirin - anti platelet: reduced risk of complete obstruction and infarction.
ACE inhibitors - reduce hypertension by reducing vasoconstriction.
Beta blockers - reduce force of contraction and excitability of cardiac muscle. Prevent arrhythmias.
Ca channel blockers - relax smooth muscle and cause vasodilation to reduce hypertension.
Diuretics - reduce hypertension by reducing salt and water, plasma volume and ultimately the cardiac workload.
What are the surgical therapies for angina/acute coronary syndrome?
Angioplasty and stenting - dilate the obstructed/narrowed vessels.
CABG - Bypass the obstruction/narrowing
When is angioplasty/stenting especially useful?
In treating a STEMI (S - T elevation myocardial infarction: where major artery supplying the heart muscle is blocked)
In what type of patient is a CABG especially useful for?
Elderly patient - the bypass is only beneficial for 10 years.
This could be contra-indicated by a frail elderly individual as the surgery is risky and requires the heart to be stopped and restarted.
What are the diagnostic tools used in acute coronary syndromes?
Troponin biomarkers - released into the blood when the heart muscle is damaged.
ECG:
STEMI
NSTEMI
S-T segment is elevated in an individual having a myocardial infarction which means there is complete obstruction of a coronary artery.