I have experienced atrial fibrillation, tachycardia and PVCs for the past five years, with some success from two cardiac ablations.

On one occasion a doctor prescribed Keflex for an unrelated purpose, and for one week my arrhytmia ceased.

Both my wife and best friend (with whom we share the house) have also experienced some kind of heart rhythm or low blood pressume issues, with my wife also having a cardiac ablation.

The coincidence of my wife and I having rhythm problems, and the abatement of symptoms after Keflex, have led me to search out possible connections.