CRITICAL CARE A DAY
Q: Why digoxin should be avoided in cardiac amyloidosis?
Answer: Patients with cardiac amyloidosis are at a high risk of "dig toxicity" which usually outweighs any inotropic benefit. Digoxin binds avidly to amyloid fibrils. In these patients, cardiac digoxin concentration can't be accurately measured and serum digoxin level is extremely unreliable. If it is used in ICU for rate control in atrial fibrillation (chronotropic effect), a huge caution should be applied.
1. Rubinow A, Skinner M, Cohen AS. Digoxin sensitivity in amyloid cardiomyopathy. Circulation 1981; 63:1285.
2. Falk RH. Diagnosis and management of the cardiac amyloidoses. Circulation 2005; 112:2047.