The Effect of Race and Gender on Response to Milrinone and Time to LVAD or Transplant

Abstract

<h3>Purpose</h3> This study aims to determine whether a patient's race or gender has any effect on the hemodynamic response to milrinone and time to LVAD or transplant. <h3>Methods</h3> Patients with systolic heart failure in an urban academic center were referred for a right heart catheterization and milrinone drug study between June 2014 and November 2018. Drug studies were performed and hemodynamics, including Fick cardiac index (Fick CI) and pulmonary capillary wedge pressure (PCWP), were measured before and after infusion of milrinone at 5mcg/kg/min for 10 min. In addition, time to LVAD or transplant was recorded and results were compared by gender and race. Univariate and multivariate logistic regression were then performed and the results were analyzed retrospectively. <h3>Results</h3> A total of 237 milrinone drug studies were performed during the study period. 54% of the patients were black (n=127), 46% identified as other (white, asian, latino, arabic; n=110), 34% were women (n=80) and 66% were men (n=157). Black patients had a less robust percent decrease in PCWP than patients of other race (-0.2096 ± 0.2299 vs -0.2687 ± 0.2290, p=0.05) and black patients had a greater percent increase in Fick CI, though results did not reach significance (0.3776 [0.1667-0.5714] vs 0.3125 [0.1667-0.4444], p=0.10). Women had a less robust percent decrease in PCWP than men (-0.1721 ± 0.2264 vs -0.2687 ± 0.2270, 0.002), but women did not have a significant change in Fick CI compared to men (0.3298 [0.1579 - 0.5217] vs 0.3604 [0.1694 - 0.5188], p=0.61). Freedom from LVAD or transplant for black patients was 50% at 65 months and 30% at 52 months for other race (p=0.008). There was no significant difference in freedom from LVAD or transplant between men and women (Fig 1). <h3>Conclusion</h3> Black patients and women may have a less robust response to milrinone than their counterparts, and black patients may be referred for LVAD or transplant less quickly than patients of other race. Additional studies are needed to determine if pharmacogenomics and implicit bias may play a role in these results.