Is electric blanket harmful to pacemaker?

Harmless.

Electric blankets will not have harmful effects on people who carry pacemakers. Pacemaker is a kind of medical equipment, which aims to treat arrhythmia and other related problems, while electric blanket mainly provides warmth through low-frequency heating. There is no obvious conflict between the two in working principle and frequency, and the use of electric blanket will not interfere with or affect the function of pacemaker.