coronary heart disease

Question 1

mechanism of nitrates

Answer 1

Releases NO from nitrates, causing relaxation of muscles through inactivated myosin-LC → hence vasodilation (see mechanism in anti-hypertensives)

Vasodilation includes venodilation and arteriolar dilation
Venodilation → decreases preload as more blood pools in veins, lesser go into heart → less workload for heart + less preload (hence less stretch of myocardium and less O2 requirement)
Arteriolar dilation → decreases afterload, reducing workload of heart → amount of O2 needed by heart reduces

Coronary Vasodilation: Nitroglycerin dilates (widens) the coronary arteries, increasing blood flow to the ischemic areas of the heart, helping to alleviate angina.

Question 2

use of ISDN

Answer 2

for angina pectoris prophylaxis

Question 3

Glycerol Nitrates use

Answer 3

acute treatment of MI and for angina

Question 4

mechanism of ivabradine

Answer 4

inhibition of the cardiac pacemaker current that controls spontaneous diastolic depolarisation in the sinus node and regulates heart rate → heart beats slower → reduces cardiac workload and myocardial oxygen consumption

Question 5

adverse effects of ivabradine

Answer 5

visual problems (transient enhanced brightness in a limited area of the visual field), dizziness due to bradycardia