Targeted potassium levels to decrease arrhythmia burden in high risk patients with cardiovascular diseases (POTCAST):...

Area of Science:

• Cardiology
• Electrophysiology
• Clinical Trials

Background:

• Low plasma potassium (p-K) is linked to increased malignant arrhythmia risk.
• Observational data suggest upper-normal p-K levels offer cardiovascular protection.
• Randomized trials are needed to confirm if increasing p-K improves outcomes.

Purpose of the Study:

• To determine if elevated p-K reduces malignant arrhythmias and all-cause death in high-risk cardiovascular patients with an implantable cardioverter defibrillator (ICD).
• To assess the safety and efficacy of achieving and maintaining high-normal p-K levels (4.5-5.0 mmol/L) using available treatments and dietary guidance.

Main Methods:

• Prospective, randomized, open-label study of 1,000 high-risk patients.
• Randomization 1:1 to an investigational arm aiming for high-normal p-K or usual care.
• Follow-up for four years or until 291 composite primary endpoint events (ventricular tachycardia, ICD therapy, all-cause mortality).

Main Results:

• 739 patients randomized to date.
• Study aims to provide α=0.05 and 1-β=0.80 power.
• Primary endpoint includes specific ventricular tachycardia, appropriate ICD therapy, and all-cause mortality.

Conclusions:

• The POTCAST trial design is presented.
• Patient enrollment began in 2019, with expected completion in 2022.
• The study will evaluate if increasing p-K is a viable strategy against malignant arrhythmias.