Hyperkalemia in Patients With Left Ventricular Assist Devices

Background: Both hypo- and hyperkalemia are associated with adverse events in heart failure patients. Their effects on patients with left ventricular assist devices (LVADs) remains unknown. Methods and Results: The cohort included consecutive patients undergoing LVAD implantation between 2014 and 2018. In all, 170 patients (median age 56 years; 117 males) were stratified according to serum potassium levels 1 month after implantation into 3 groups: hypokalemia (<3.5 mEq/L; n=15), normokalemia (n=146), and hyperkalemia (>5.0 mEq/L; n=9). Compared with the normokalemia group, the adjusted hazard ratios for 1-year mortality were 0.91 (95% confidence interval [CI] 0.21–3.92) for hypokalemia and 4.14 (95% CI 1.47–11.65) for hyperkalemia. In the hyperkalemia group, the prevalence of renin-angiotensin-aldosterone system inhibitors decreased and serum potassium levels normalized following the first month. Conclusions: Hyperkalemia was associated with increased mortality during LVAD support. Management of serum potassium needs further investigation.