Anti angina

Question 1

Types of anti angina drugs

Answer 1

• Nitrates
• beta blockers
• Ca channel inhibitors
• Ivabradine

Question 2

Examples of nitrates

Answer 2

• nitroglycerin
• isosorbide dinitrate
• isosorbide mononitrate

Question 3

MOA of nitrates

Answer 3

• release NO which activates guanylyl cyclase -> convert GTP to cGMP -> smooth muscle relaxation & vasodilation -> reduce stress on heart

Effects
- venous dilation (occurs first) -> peripheral blood pooling -> reduce preload; ALSO reduce end diastolic pressure, thus dilation of coronary artery (less compressed between pericardium & ventricles)
- arteriole dilation -> reduce pressure and afterload
- coronary artery dilation -> increase blood flow to heart to relieve ischemia

Question 4

Nitroglycerin clinical indication & mode of administration

Answer 4

• SUBLINGUAL: 1-5min onset duration; 10-30min duration of action
• TRANSDERMAL: 30-60min OD; 7-10hr DOA -> cannot use for ACUTE angina

Question 5

isosorbide MN/ ISDN clinical indication & mode of administration

Answer 5

• angina PROPHYLAXIS
• administration: oral
  ISMN: 45min OD; 6-24hr DOA
  ISDN: 1hr OD; 8-12hr DOA

Question 6

Beta blocker MOA

Answer 6

• decrease contractility of heart -> reduce O2 demand, relieve angina

Question 7

Ca channel blockers examples

Answer 7

• verapamil, diltiazem (non DHP)
• nifedipine, amlodipine (DHP)

Question 8

Ca channel blocker effects on lowering BP, vasodilation, cardiac depressant

Answer 8

lower BP: DHP = nonDHP
vasodilation: DHP>nonDHP; Nifedipine > diltiazem > verapamil
cardiac depressant: nonDHP>DHP; Verapamil > diltiazem > Nifedipine

*nonDHP depresses SA/AV node (cardiac depressant) -> use for arrhythmia
*DHP cause vasodilation -> use for hypertension
*both DHP&nonDHP decrease contractility of heart -> reduce oxygen requirement -> both use for angina

Question 9

Ca channel blocker adverse effects

Answer 9

• cardiac depression (AV block, bradycardia)

Question 10

DHP clinical indications

Answer 10

• hypertension
• stable angina (amlodipine)
• reduce risk of MI (amlodipine)

Question 11

Ivabradine MOA

Answer 11

• pure heart rate lowering agent
• specific inhibition of the cardiac pacemaker that controls spontaneous diastolic depolarisation in SA node -> reduce cardiac workload -> decrease O2 consumption

Question 12

Ivabradine clinical indications

Answer 12

• stable angina
• chronic heart failure with systolic dysfunction, in patients with sinus rhythm and whose heart rate >75 bpm

Question 13

Ivabradine adverse effects

Answer 13

• bradycardia
• LUMINOUS PHENOMENA (enhanced brightness in vision)