Postoperative Tolvaptan Use in Left Ventricular Assist Device Implantation Patients: The TOLVAD Study

Abstract

Purpose Tolvaptan, a selective vasopressin type-2 antagonist, has been shown to increase serum sodium (Na) and urine output in hyponatremic left ventricular assist device (LVAD) patients in retrospective studies. We aimed to assess the efficacy of tolvaptan in this population in a prospective, randomized study. Methods We conducted a prospective, randomized, non-blinded study of LVAD recipients with post-operative hyponatremia (Na Results A total of 33 patients were consented, 30 of whom developed post-operative hyponatremia. Two were excluded due to new onset renal failure requiring hemodialysis prior to development of hyponatremia. Of 28 eligible patients (21% women, 54% Black, 32% ischemic cardiomyopathy) 15 were randomized to tolvaptan (TLV), and 13 were randomized to standard care alone (No-TLV). Patients in TLV had a significant increase in Na from randomization to discharge, 133 (IQR 132-134) to 135 mEq/L (IQR 134-137), p=0.018, while those in No-TLV did not have a significant change in Na, 133 (IQR 132-134) to 134 mEq/L (IQR 132-136), p=0.15 (1A). There were no significant differences in renal function in either arm of the study: eGFR 76 (IQR 51-99) to 80 mL/min/1.73m2 (IQR 66-90), p=0.97 in TLV versus eGFR 78 (IQR 56-115) to 115 mL/min/1.73m2 (IQR 56-120), p=0.13 in No-TLV (1B). Patients in TLV had significantly more urine output than those in No-TLV during their first 24 hours of hyponatremia (3294 vs 2155 mL, p=0.043) and during last 24 hours of hyponatremia prior to sodium correction (4177 vs 2739 mL, p Conclusion Tolvaptan improves Na in hyponatremic post-operative LVAD patients when compared to those not receiving tolvaptan without adversely impacting renal function.