Use of Outpatient Intravenous Calcitropes for Heart Failure in the United States.

Background: Outpatient calcitrope infusions-that is, the cardiac inotropes milrinone and dobutamine-are often used for bridge to transplantation and palliation in advanced heart failure, but few data exist about the real-world use of these agents.

Methods And Results: We used the Symphony Integrated DataVerse of commercial, managed Medicare, and Medicaid insurance claims of approximately 280 million people (2012-2020) to determine the incidence and characteristics of ambulatory calcitrope use. Demographics were calculated, including geographic densities at the metropolitan statistical area level. A population projection normalized for age, sex, and location was extrapolated to the total US population. Ambulatory dispensing of milrinone was found in 10,533 outpatients, 1867 in 2019. Ambulatory dobutamine use was found in 4967 outpatients, 836 in 2019. The 2019 total US projection was 3411 for milrinone and 1281 for dobutamine. The mean age was 62 years for milrinone and 68 for dobutamine. Males represented 70% of use. There were differences between drugs in geographic distribution, with more milrinone use in the Northeast and South and more dobutamine use in the Midwest. Duration of use was 4.6 ± 7.2 months for milrinone and 1.8 ± 4.0 months for dobutamine. Of the patients receiving milrinone, 30.6% subsequently underwent cardiac transplantation or left ventricular assist device placement, whereas 10% receiving dobutamine went on to advanced therapies. Less than 0.5% of patients received calcitropes while enrolled in hospice care.

Conclusions: More than 4000 patients receive outpatient infusion of calcitropes annually in the outpatient setting. Men are much more likely to receive these medications. A minority of the use is as a bridge to advanced therapies. Geographic variability in use suggests better evidence and consistent guidelines may be helpful.