Mechanism of action of digitalis in atrial fibrillation is: (A) By Causing bradycarlia, (B) Na+ K+ ATPase inhibition, (C) Increase in refractoriness of AV nodal tissue, (D) By Causing bradycarlia
Answer is C. (Ref: KDT 6/ep502) Digitalis acts in CHF by inhibiting Na+-K+-ATPase whereas in AF, it acts by decreasing the conduction through AV node.