PHILADELPHIA – Milrinone was associated with a 50% reduction in mortality, compared with dobutamine, in patients with heart failure who were receiving home inotropes as a bridge to advanced therapies, according to results of a large U.S. registry study.
The survival profile for milrinone was more favorable than that for dobutamine across various indications for use, including bridge to transplant, bridge to mechanical support, and palliation.
The findings illustrate an “urgent need” for randomized trials that compare inotropic therapy strategies in patients with end-stage heart failure, said investigator Behram P. Mody, MD, of the division of cardiology at the University of California, San Diego, La Jolla.
“Although [there is] the possibility of selection bias and there are confounding variables, this consistent finding may reflect a true benefit of milrinone,” Dr. Mody said in a presentation at the annual scientific meeting of the Heart Failure Society of America
The evidence to support use of continuous outpatient intravenous inotropic therapy in stage D heart failure is limited and comes mainly from case series, and small, randomized trials demonstrating poor outcomes, Dr. Mody explained.
“Long-term survival associated with home inotropes in the modern era of guideline-directed medical and device therapy is poorly defined,” he said.
The retrospective study Dr. Mody presented at the meeting included 1,149 patients (mean age, 60 years; 29.9% women) who received continuous intravenous outpatient inotropic therapy (milrinone or dobutamine) from 2015 to 2017. This is possibly the largest body of data reported to date of patients receiving home inotropes, he said.
For the overall population, the estimated 1-year survival rate was 71% with milrinone, compared with 46% for dobutamine (P less than .0001), Dr. Mody reported. After adjusting for age, gender, weight, and indication, milrinone use was still significantly associated with lower mortality, compared with dobutamine (hazard ratio, 0.50; 95% confidence interval, 0.39-0.64; P less than .0001).
The survival benefit of milrinone over dobutamine was also significant in subsets of patients receiving home inotropes as bridge to transplant, bridge to mechanical support, or palliation. A similar trend, though not statistically significant, was seen for inotropes used as a bridge to decision, he added.
Mortality was generally higher in patients receiving inotropes as palliation, as opposed to bridge therapy, with 1-year survival of 55.0% and 65.6%, respectively, and median survival of 461 days and 584 days.
These findings suggest home inotropes can be “beneficial” in patients with end-stage heart failure in an era of guideline-directed medical therapy and greater defibrillator use, Dr. Mody said.
“I’m not saying that it should replace left ventricular assist devices as the bridge to transplant,” he added, “but it could be an alternative strategy for our patients.”
No funding source was given. Dr. Mody had no disclosures related to the study.
SOURCE: Mody BP et al. J Card Fail. 2019 Sep 14. .