CVD tutorial

Question 1

What is the relationship between obesity and hypertension?

Answer 1

3-4 times greater risk of hypertension is obese that if not obese

Question 2

Why is the relationship between obesity and hypertension such?

Answer 2

Adipose tissue produces ATII in an unregulated way, as opposed to the kidneys, which do this in a regulated way. Hence AtII causes vasoconstriction leading to increases TPR and MAP.

Question 3

What is the relationship between smoking and mortality from heart disease and why is this?

Answer 3

• Smoking is associated with a 60% increase in mortality, from heart disease in men aged 55-64
• Nicotine brings about direct vasoconstriction effects, as well as stimulates sympathetic ganglia to increase BP

Question 4

Why does reduced salt intake reduce blood pressure?

Answer 4

Reduced salt intake will reduce water retention, and in turn lower his BP

Question 5

What type of a drug bendrofluazide and how does it reduce blood pressure?
Where does it act?

Answer 5

Thiazide diuretic

• Reduce fluid retention by increasing urinary excretion
• They act on the distal tubule of the kidney, to inhibit sodium-chloride symport -> more water in the urine
• This causes the early response in BP drop
• Later phase effect is due to a direct effect on the blood vessels themselves although the mechanism by which this occurs is obscure
• Subtle alterations in the contractile response of vascular smooth muscle?

Question 6

What type of drug is ramipril and how does it work?

Answer 6

ACE inhibitor

• Decreased AT11 -> reduced BP
• ATII is a vasoconstricter and it increases noradrenaline production form sympathetic nerves. It also generates aldosterone -> Na retention.
• Bradykinin is metabolised by ACE into inactive metabolites. Bradykinin is an inflammatory mediator, involved in vasodilation; hence the prescription of ACE inhibitors prevents the removal of vasodilatory effects exerted by bradykinin

Question 7

Why is ramipril given an ACE inhibitor as second line when a diuretic is already being given?

Answer 7

Diuretic reduces BP which is stimulating the renin-angiotensin system in order to compensate for this fall in BP. Prescribing an ACE inhibitor is a good second line treatment because of this - RAS is more active so the drug is more likely to have a greater effect. Otherwise, ACE inhibitors wouldn’t necessarily be prescribed

Question 8

What is normal ventricular rate?

Answer 8

Around 80

Question 9

What is digoxin?

Answer 9

A cardiac glycoside used to treat various heart conditions (most frequently AF).

Question 10

Why is warfarin given to patients with atrial fibrillation?

Answer 10

Atrial fibrillation can lead to thrombus formation in the arteries. The warfarin (anticoagulant) thins the blood to prevent this complication.

Question 11

How does digoxin work?

Answer 11

• Inhibits Na-K ATPase in the heart (it slows the heart down and increases contractility)
• It also activates the vagus nerve

Question 12

How does warfarin work?

Answer 12

Interferes with vitamin K metabolism in the coagulation cascade (wipes out F2, F7, F9 and F10)

Question 13

What is GTN?

Answer 13

Glyceryl trintitrate/nitroglycerin

Question 14

Why are medications given sublingually?

Answer 14

That area is highly vascularised so will be quickly absorbed

Question 15

Why are patients with angina prescribed GTN?

Answer 15

The GTN generates nitric oxide (vasodilator), and is prescribed to treat and prevent chest pain from not enough blood flow to the heart.

Question 16

What is bisoprolol?

Answer 16

Bisoprolol is a cardio-selective beta blocker (beta-1 antagonism)

Question 17

How does aspirin work?

Answer 17

Aspirin is an antiplatelet drug (COX 1 inhibitor). This prevents the conversion of arachidonic acid into prostaglandins and thromboxane A2 (prevents platelet aggregation and clotting).

Question 18

What is congestive heart failure?

Answer 18

Heart failure - A term for the physiological state in which cardiac output is insufficient for the body’s needs. Congestive is used to described the pooling in extremities (e.g. leg and ankle swelling).

Question 19

What is frusemide?

Answer 19

It is a loop diuretic; it inhibits the luminal Na-K-Cl cotransporter in the thick ascending limb.

Question 20

What is perindopril?

Answer 20

Perindopril is a long-acting ACE inhibitor, used to treat high blood pressure

Question 21

Why are beta blockers prescribed in a low dose first especially in heart failure patients?

Answer 21

They could become hypotensive if the heart slows down so much

Question 22

What is the relationship between catecholamine levels and heart failure prognosis?

Answer 22

Catecholamine levels are known to increase in proportion to the severity of symptoms in patients with heart failure. Patients with the highest levels of norepinephrine have the least favorable prognosis.

β-Blockers have been shown to be effective in heart failure that has been stabilised with an ACE inhibitor and diuretic. If introduced gradually in small doses they improve symptoms and survival.

Question 23

Which people will benefit from salt restriction? Is salt restriction effective in lowering BP?

Answer 23

A reduction in salt intake will have a small but significant effect in most people. Approx 30% HT patients are sensitive to salt and found to have low levels of renin. Salt restriction should help in these patients.

Question 24

Why are Afro-Caribbeans and elderly people not given ACE inhibitors?

Answer 24

They tend to have low renin hypertension so respond less well to monotherapy with ACE inhibitors.