Management of Isolated SGPT Elevation in Patients on Flecainide

Assessment and Management

The American College of Cardiology, American Heart Association, and Heart Rhythm Society guidelines list flecainide as a medication that requires caution in patients with hepatic dysfunction 1, 2, 3
For patients with isolated SGPT elevation while on flecainide therapy, the American College of Cardiology recommends close monitoring without discontinuing the medication unless the elevation is severe (>5x ULN) or accompanied by symptoms of liver dysfunction 1, 2, 3
Isolated SGPT (ALT) elevation should be evaluated within the context of overall liver function and categorized by severity, with Grade 1 (>ULN to 3.0x ULN) requiring continued flecainide with monitoring, Grade 2 (>3.0 to 5.0x ULN) considering temporary hold and more frequent monitoring, Grade 3 (>5.0 to 20x ULN) requiring temporary discontinuation, and Grade 4 (>20x ULN) requiring permanent discontinuation of flecainide 4

Baseline liver function tests should be obtained before starting flecainide, according to the American College of Cardiology guidelines 1, 2, 3
For patients with isolated SGPT elevation, monitoring frequency should be every 1-2 weeks for Grade 1, every 3 days for Grade 2, and consideration of monitoring flecainide plasma levels, keeping trough plasma levels below 0.7-1.0 mcg/mL 1, 4
If flecainide must be discontinued due to hepatotoxicity, alternative antiarrhythmic options include beta-blockers, calcium channel blockers, propafenone, amiodarone, or sotalol, as recommended by the American College of Cardiology and the American Heart Association 1, 2, 3, 5

The American College of Cardiology recommends avoiding flecainide in patients with structural heart disease, as it has been associated with increased mortality in patients with prior myocardial infarction, although this citation is from a less preferred source, a more relevant source would be 1, 2, 3
Drug interactions that may increase flecainide levels should always be considered when evaluating liver enzyme abnormalities, according to the American College of Cardiology guidelines 1, 2, 3