CARDIO: BETA BLOCKERS

Question 1

BETA BLOCKERS: INDICATIONS

Answer 1

• Ischaemic Heart Dx - Angina + ACS
• CHF
• AFib
• SVT
• HTN

Question 2

BETA BLOCKERS: MOA

Answer 2

• Beta 1 receptors in the heart = Reduce the force of contraction and speed of conduction in the heart
• Relieves myocardial ischaemia and reduces cardiac work and oxygen demand, increasing myocardial perfusion
• Improves prognosis in heart failure by protecting the heart from the effects of chronic sympathetic stimulation
• Slow ventricular rate in AFib mainly by prolonging the refractory period of the AV Node
• Reduces Renin secretion, therefore decreasing BP

Question 3

BETA BLOCKERS: ADVERSE EFFECTS

Answer 3

• Fatigue
• Cold extremities
• HA
• GI disturbance (eg nausea)
• Sleep disturbance and nightmares
• Impotence in men

Question 4

BETA BLOCKERS: WARNINGS

Answer 4

• Asthma - life threatening bronchospasm
• COPD = safe, choose a b1 selective (atenolol etc), rather than non selective (propanolol)
• Heart failure, use low dose first
• Avoid in haemodynamically unstable patients
• CI in heart block
• Dosage reduction in hepatic failure

Question 5

BETA BLOCKERS: INTERACTIONS

Answer 5

• Non dyhydropine calcium channel blockers (verapamil, diltiazem
  => combination causes heart failure, bradycardia and asystole

Question 6

BETA BLOCKERS: EXAMPLES

Answer 6

• Bisoprolol
• Atenolol
• Propanolol
• Metopropol