Study Notes >> Revision Questions >> Cardiovascular (Preview)
Revision Questions: Cardiovascular (Preview)
- List the classes and subclasses of anti-arrhythmic drugs under the Vaughan-Williams system and give an example of a drug in each class.
- Why do ACE inhibitors reduce blood pressure?
- Which calcium channel blocker does not have any significant effects on the myocardium?
- In a hypertensive patient who is taking insulin to treat diabetes mellitus, which class of drugs is to be used with extra caution and advice to the patient?
- Differentiate the following classes of drugs used in hypertension in terms of causing potassium changes in the body.
- Angiotensin II antagonist
- Loop diuretics
- Thiazide diuretics
- Aldosterone antagonists & potassium-sparing diuretics
- Vaughan-Williams classification of anti-arrhythmic drugs
- ACE-I block conversion of angiotensin I to angiotensin II and also inhibit the breakdown of bradykinin. They reduce the effects of angiotensin II-induced vasoconstriction, sodium retention and aldosterone release.
- Diltiazem acts on both cardiac and vascular smooth muscle, but it has less effect on cardiac cells hence may be used safely with beta blockers in hypertension.
- Beta-blockers may mask signs of acute hypoglycaemia (eg. tachycardia, tremor). Beta1-selective beta-blockers such as atenolol, metoprolol and bisoprolol are preferable. They produce less bronchospasm, less peripheral vasoconstriction and less alteration to glucose/lipid metabolism.
- Potassium changes:
|Ia||Fast channel blockers||Quinidine, procainamide, disopyramide|
|IV||Slow-channel blockers||Verapamil, diltiazem|