Pharmacological treatment of angina Flashcards
What shrinks the window for coronary perfusion?
- Shortening diastole
- Increased ventricular end diastolic pressure
- Reduced diastolic arterial pressure
What causes angina
Coronary ischaemia as a result of atherosclerosis
What is sudden ischaemia usually caused by?
Thrombosis
What is variant angina caused by?
Coronary spasms
What can calcium overload cause?
- May cause cell death and ischaemias
What is the definition of angina?
Chest pain due to inadequate supply of oxygen to the heart
Whhat is the characteristic distribution of angina pain?
- Often retrosternal, or left side of chest and can radiate to the left arm, neck, jaw and back
What is angina pectoris (stable angina) brought about by?
Exertion, cold, excitement
What can angina be a precursor for?
Heart attack
What is variant (Printzmetal’s) angina?
Caused by coronary artery spasm (supply ischemia)
What types of angina are supply angina?
Printzmetal’s variant angina and unstable angina
What is unstable angina brought about by?
- Associated with a thrombus around a ruptured atheromatous plaque but without complete occlusion of the vessel (similar to MI)
What type of angina is associated with platelet aggregation?
Unstable
What drugs can be used to reduce chest pain symptoms (angina)?
- Beta-blockers
- Nitrates
- Calcium channel antagonists
- Nicorandil
- Ivabradine
- Ranolazine
What drugs can be used to prolong survival (angina)?
- Beta-blockers
- Aspirin
- Statins
- ACE inhibitors
- Angiotensin II Receptor blockers
What classes ofdrugs are used to treat symptoms of angina?
- Short-acting nitrate
- Beta-blockers
- Addition of CCBs can be considered
If beta blockers or CCB monotherapy is ineffective and the other option is contraindicated what other drugs may be addtionally used?
Nicorandil or ivabradine
What drugs used to treat angina are classed as vasodilators?
- Organic nitrates
- Nicorandil
- Calcium antagonists
What classes of drugs slow down the heart?
Beta blockers and ivabradine
Name drugs that are classed as organic nitrates?
Glyceryl trinitrate and isosorbide mononitrte
How do nitrates specifically work?
They are metabolised to NO and relax smooth muscle
How does the administration of GTN differ between unstable and stable angina?
- Stable = sublingually
- Unstable = IV
What are the unwanted side-effects of organic nitrates?
- Headaches
- Postural hypotension
What other conditions can be treated with organic nitrates?
- Acute HF (IV GTN)
- Chronic HF (isosorbide mononitrate with hydralazine)
When is isosorbide mononitrate with hydralazine administred for Chronic HF?
- Often in patients with african origin
- Or patient cannot tolerate more commonly used CHF drugs
What are the common Beta blockers administred for angina?
Bisoprolol, atenolol
How do calcium channel blockers work?
They prevent the opening of voltage-gated L-type Ca2+ channels.
Mainly affect the heart and smooth muscle to inhibit calcium entry upon muscle cell depolarisation
What are the two main types of CCBs?
- Dihydropyridine derivatives
- Rate-limiting
What drugs are considred Rate-limiting CCBs?
Verapamil and diltiazem
What drugs are considred - Dihydropyridine derivative CCBs?
Amlodipine and lercanidipine
What type of CCBs can can reduce and impair AV conduction and myocardial contractility?
Rate-limiting CCBs
What can the side-effects of CCBs be?
- Headache
- Constipation
- Ankle oedema
What CCB is mainly used in antidysrhythmics?
Verapamil
What CCBs can be used to treat hypertension?
- Mainly amlodipine or lercanidpine
What anti-anginal drug inhibits Funny channels?
Ivabradine
What unique anti-anginal is used as a last resort to treat angina?
Ranolazine
What anti-anginal drug is classed as a potassium channel activator
Nicorandil (used in patients who remain symptomatic despite management with other drugs)
What are the side-effects of nicorandil?
- Headaches
- Flushing
- Dizziness
How do potassium channel activators work (nicorandil)?
- Combines activation of potassium K+ATP channels with nitrovasodilator actions
- Causes hyperpolariation of vascular smooth muscle
What class of CCBs are safe in patients with HF?
DHP derivatives (amlodipine and lercanidipine)
In what type of angina are DHP derived CCBs used instead of Beta-blockers?
Printzmetal angina
In what conditions can rate-limiting CCBs (diltiazem and verapamil) not be used?
- HF
- Bradycardia
- AV block
- In presence of beta-blocker
What drug prevents the recurrence of supraventricular tachycardia (SVT)?
Verapamil
