Treatment of Angina Flashcards
When does perfusion of the heart muscle occur and why?
During diastole, due to the rebound effect the blood has on the aortic valve
What factors shorten diastole?
Exercise and increased HR
What type of pathology causes an increase in end diastolic pressure?
Faulty valves, meaning more residual blood is left in the ventricles following systole
What does coronary ischaemia normally result from?
Atherosclerosis
What does sudden ischaemia normally result from?
Thrombosis
What can coronary spasms cause?
Angina
On a cellular level, what can ischaemia cause?
Cellular calcium overload leading to cell death and dysrhythmias
What can cause inadequate supply of O2 to the heart (angina pectoris)?
Changes from hot to cold and vice versa
Exercise
Increased adrenaline
Other local factors
Even if an atherosclerotic plaque doesn’t completely occlude the artery, why is it still dangerous?
Flow is so greatly reduced that O2 reaching the heart is reduced
Name the 3 types of angina.
Printzmetal’s Variant Angina
Chronic Stable Angina
Unstable Angina
What is chronic stable angina caused by?
Fixed narrowing of the coronary arteries causing predictable chest pain upon exertion
What is variant angina caused by?
Coronary spasms
Name the two methods by which angina treating drugs work?
Vasodilators
Slows down the heart which decreases the metabolic demands of the coronary muscle
What type of Ca2+ channels do calcium antagonists prevent the opening of?
L type
See slide 12
For deets
Which of the following drugs are safe for use in patients suffering with heart failure? Amlodipine Verapamil Lercanidipine Diltiazem
Amlodipine
Lercanidipine
List some side effects of angina treatment drugs.
Headaches
Constipation
Ankle oedema
What is the action of glyceryl trinitrate and isosorbide mononitrate?
Vasodilators; work by being metabolised to nitric oxide and relax smooth muscle, in turn decreasing preload.
They also dilate collateral coronary vessels, improving distribution of coronary blood flow towards ischaemic areas
What are some common side effects of organic nitrate treatment?
Headache
Postural hypotension
Describe the mechanism of action of ivabradine.
Inhibits funny ‘f’ type channels in the heart, reducing the pacemaker activity (pacemaker potential slope decreases, meaning depolarisation takes longer to ensue and heart rate is reduced
