Inotropic agents (digoxin) for HF

How does digoxin work?

encourages the heart to beat more strongly

What is the source of digoxin?

white and purple foxglove

What chemical group is digoxin?

cardenolide

What are the pharmacological actions of digoxin, which can be split into 2?

• cardiac mechanical effects- increases contractility resulting from inhibition of Na and K pump

• cardiac electrical effects- indirect actions increase at low PN, and at high SN activity

• direct actions increase automaticity 

What are the mechanisms of clinical effects of digoxin?

• increased contractility increases CO and less hypoperfusion symptoms

• natriuresis decreases PV which lessens congestive symptoms

• neurohormonal control decreases: plasma noradrenaline, PNS activity, RAAS activity, increases vagal tone and normalises arterial baroreceptors.

What is the patient indication for digoxin?

patients with HFrEF with worsening or persistent severe HF symptoms despite optimal therapy with ACEI, BB, MRA, SGLT2I

What are the possible adverse effects of digoxin?

• cardiac arrythmias

• neurological disturbances

• GIT disturbances