JAMA

ESC 2024: Is potassium supplementation necessary after cardiac bypass surgery?

September 5, 2024

For preventing afib after cardiac surgery (AFACS), giving potassium supplements only when levels drop below 3.6 mEq/L was just as effective as the common practice of maintaining levels at or above 4.5 mEq/L, according to findings presented at the European Society of Cardiology meeting. This lower threshold did not lead to more irregular heartbeats or negative health effects.

• In the randomized TIGHT K trial, 1,690 patients (mean age, 65 years; 15% female) at 23 cardiac surgical centers were randomly assigned to tight or relaxed potassium control (only supplementing if serum potassium concentration fell <4.5 mEq/L or <3.6 mEq/L, respectively). Primary end point was clinically and electrocardiographically confirmed new-onset AFACS in the first 5 days after coronary artery bypass grafting (CABG) surgery or until hospital discharge, whichever occurred first. Secondary outcomes included other heart rhythm-related events, clinical outcomes, and cost related to the intervention.
• New-onset afib occurred in 26.2% of patients in the tight group and 27.8% of patients in the relaxed group (risk difference, 1.7%). No significant differences were detected between the groups in the incidence of ≥1 AFACS episode, non-AFACS dysrhythmias, in-patient mortality, or length of stay.
• Per-patient cost for purchasing and administering potassium was significantly lower in the relaxed group (mean difference, $111.89).

Source:

O'Brien B, et al; TIGHT K investigators. (2024, August 31). JAMA. Potassium Supplementation and Prevention of Atrial Fibrillation After Cardiac Surgery: The TIGHT K Randomized Clinical Trial. https://pubmed.ncbi.nlm.nih.gov/39215972/