PHYL 2066 Module 5: cardiovascular pharmacology

What do i need to know how to treat?

Hypertension, Angina and Cardiac failure.

What are some complications of hypertension?

Possibility of a stroke, blood vessel damage, heart attack/ failure, kidney failure.

What are some Antihypertensives?

Diuretics, Directly acting vasodilators, calcium channel blockers, Sympathetic agonists (peripheral and central), Beta blockers.

How do calcium blockers work?

They inhibit movement of calcium ions into vascular and cardiac muscle. Interfering with inward movement of Ca ions, affecting the depolarisation rate, and contraction of heart. The relaxant effects mainly arterioles smooth muscle.

What happen as a result of calcium channel blockers?

Peripheral and coronary vasodilation and decreases heart rate and contractility.

What do beta-blockers do?

Beta blockers are selective agonists for beta-1 adrenergic receptors. They block the beta receptors in cardiac myocytes and reduce the affect of adrenaline or noradrenaline.

What does the use of beta-blockers result in?

reduced heart rate and reduced ventricular contractility.

What is Angina Pectoris?

Chest pain?

What can cause Angina pectoris?

Myocardial ischaemia caused by coronary artery disease.

What is coronary artery disease caused by?

The build up of plaque on the wall of the coronary arteries, arteriosclerosis.

Why does myocardial ischaemia cause chest pain?

It results in low blood flow through coronary arteries, leading to inadequate oxygenation of chest pain, and eventually myocyte cell death.

What is the difference between stable and unstable angina pectoris?

Stable angina is predictable, and caused by exertion, where as unstable angina has no predictable onset, and is randomly occurring.

What causes stable angina?

The build up of plaque in the coronary arteries, where it has a thick layer of fibre on the outside of the plaque. this causes blockage, leading to a lack of oxygen when exerted.

What causes unstable angina?

When the fibrous layer on the outside of the plaque is not thick enough, causing it to release plaque into the blood stream, which may cause clots.

What are the ways to target stable angina?

Target cardiac work and blood supply (via organic nitrates, vasodilators and beta-blockers), underlying aterioscleriosis (statins), and anti-thrombotic therapy (asprin)

What are the ways to treat unstable angina?

Antiplatelets and organic nitrates.

What are the ways to treat myocardial infarction?

A pyhsical bypass and stenting are physical examples of treating them, as well as some pharmacological means.

What causes angina?

A lack of supply and demand of oxygen, which will cause myocardial ischaemia.

What factors can we change to rectify angina pectoris?

By either increasing O2 supply or decreasing the O2 demand

What drugs are used to treat angina pectoris?

Vasodilators (such as nitrates or calcium blockers), Cardiac depressants (such as calcium blockers or betablockers).

What do organic nitrates do?

nitrates are a drug that when metabolised by the liver, they release nitrous oxide into systemic circulation. Nitrates produce a muscle relaxant affect when naturally produced in the body (vasodilation). Nitrates also reduce myocardial O2 demand (as a result in the reduction of the blood return).

What is heart failure?

The decrease in cardiac output as the heart muscle isnt functioning optimally.

What are the bodies natural responses (2) to heart failure?

increasing heart function by increasing adrenaline, also vasoconstriction also increases CO, the workload on the heart is increased.

What treatments are used with heart failure?

Vasodilators and diuretics (decreases work load on heart).

What are the drugs used in heart failure?

Digoxin (positive inotropic agent), ACE inhibitors and nitrates (vasodilators), diuretics and beta blockers.

What is digoxin?

digoxin shuts down the calcium-potassium pump inside cells, preventing sodium from leaving cells. as a result of this, the sodium is lower inside cells. The calcium sodium pump stops, and calcium remains in cells, leading to improved cardiac efficiency.

What do ACE inhibitors do?

ACE (angiotensin conversion enzynme) blockers prevent angiotensin 1 from converting to angiotensin 2, which decreased the load on the heart.

How do diuretics work?

They flush water and salt out of the system, reducing the work of the heart.

How are beta blockers used for heart failure?

Beta blockers prevent the harmful affects of noradrenaline and adrenaline on the heart, reducing its work.