Question

Cardiotonic and Inotropic Drugs

A 60-year-old patient who is administered digoxin has developed severe digitalis toxicity.

1. What is the usual treatment for this condition?

2. What new drugs are being used to treat heart failure that reduce hospitalizations associated with chronic heart failure

Answer 1

1.Treatment is based on patient’s signs and symptoms and the specific toxic effects

Therapeutic options are a)discontinuing digoxin therapy for stable patients and change to digoxin Fab fragments, b)cardiac pacing,

c)antiarrhythmic drugs,

d)hemodialysis for severe acute toxicity.

For prehospital care, Atropine is indicated for hemodynamically unstable bradyarrhythmic patients; lidocaine is indicated for ventricular tachycardia.

Supportive care of digitalis toxicity includes

-hydration with IV fluids, oxygenation and support of ventilatory function,

-discontinuation of the drug, and, sometimes,

-the correction of electrolyte imbalances.

-early recognition that a dysrhythmia

General principles of management include the following:

• Assessment of the severity of the toxicity and its etiology (eg, accidental ingestion, unintentional or deliberate overdose, altered digoxin metabolism due to diminished renal clearance or interaction with other drugs)

• Consideration of factors that influence treatment, including age, medical history, chronicity of digoxin intoxication, existing heart disease and/or renal insufficiency, and ECG changes

• Continuous 12-lead electrocardiogram (ECG) and cardiac monitoring

• Prompt measurement of electrolyte levels, including potassium and calcium, and of serum creatinine and digoxin levels

• Intensive care unit admission

Acute overdose or accidental ingestion: - Given activated charcoal

Binding resins (eg, cholestyramine) may bind enterohepatically-recycled digoxin and digitoxin, although no outcome studies have been performed. Binding resins may be more appropriately used for treatment of chronic toxicity in patients with renal insufficiency.

Digoxin immune Fab is extremely effective in the treatment of severe, acute digitalis toxicity.

2)

drug	mode of action
FARXIGA	reduce risk of Cardiovascular death and hospitalization
Omecamtiv mecarbil	Cardiac myosin activator; increases stroke power
Ularitide	Urodilatin analog, promotes diuresis and natriuresis through binding with NPR-A receptor
Tolvaptan	Oral V2 receptors antagonist; promotes aquaresis without increasing electrolyte concentration in urine
Serelaxin	Member of relaxin family; stimulates NO production, increases cardiac output while decreasing vascular resistance via RXFP family receptors (G-protein coupled