Treating patients with acute heart failure is difficult at the local hospitals in medically depopulated areas where cardiologists are generally absent. These patients require long-distance and time-consuming transportation to the intensive care units. It is well known that tolvaptan is effective for the treatment of congestive heart failure, but the effect of prehospital tolvaptan use in patients is not well evaluated. The aim of this study was to evaluate the efficacy and safety of prehospital tolvaptan use in patients with acute congestive heart failure who require long-distance and time-consuming transportation.

This retrospective study included 30 patients who were newly diagnosed with acute heart failure at Wakkanai City Hospital and transported to Nayoro City General Hospital between January 2013 and May 2020. The patients were classified into those who received tolvaptan (tolvaptan group, n = 18) and did not receive tolvaptan (control group, n = 12).

The percentage of patient survival at discharge did not show a statistically significant difference between the groups (100% [tolvaptan] vs. 91% [control], p = 0.414). During transportation, the percentage of patients in the tolvaptan group who required increased oxygen doses was statistically significantly lower than that in the control group (0% vs. 36%, p = 0.0181). Patients in the tolvaptan group had statistically significantly shorter intensive care unit stays (median: 2 days vs. 6 days, p = 0.0376), less days to discontinuation of oxygen (median: 2.8 days vs. 6.9 days, p < 0.00125), and less days to ambulation (median: 1.5 days vs. 7.5 days, p = 0.0362) compared with the control group.

In the tolvaptan group, blood pressure was not different; however, heart rate was statistically significantly reduced (99 ± 21 vs. 88 ± 21 beats per minute, p = 0.016) during transportation.

The use of tolvaptan in patients with acute heart failure requiring long-distance transport is safe and may show better clinical course compared with conventional therapies.