β-blockers and modifiers of myocardial metabolism

Question 1

β-blockers used for angina

Answer 1

Atenolol
Nadolol
Propanolol
Metoprolol

Question 2

β-blockers - contraindications

Answer 2

Variant angina, acute anginal attacks.
Heart failure.
Verapamil + β-blocker: significantly reduce cardiac output

Question 3

β-blockers - MOA as antianginal drugs

Answer 3

Prevent exercise-induced tachycardia and myocardial oxygen demand. Prevent reflex tachycardia from vasodilators

Question 4

β-blockers - benefits

Answer 4

Post-MI: improve survival

Question 5

Drugs that modify myocardial metabolism

Answer 5

Ranolazine

Trimetazidine

Question 6

Ranolazine - indications

Answer 6

Chronic stable angina

Question 7

Ranolazine - MOA

Answer 7

Block pathologic activation/prolongation of late inward sodium current, which prevents excessive intracellular Na and Ca accumulation.
Reduces diastolic wall tension, improve diastolic subendocardial perfusion, reduce oxygen demand.

Question 8

Ranolazine - effects

Answer 8

No effect on HR or blood pressure.
Increase exercise capacity.
Improve glycemic control and vascular endothelial function.
Decrease incidence of AF.

Question 9

Ranolazine - adverse effects

Answer 9

Dizziness, headache, nausea, constipation.

Question 10

Trimetazidine - MOA

Answer 10

Inhibits ketoacyl coenzyme-A thiolase, inhibiting β-oxidation of fatty acids. This shifts myocardial energy metabolism from fatty acids to glucose and reduce oxygen consumption.