Maximum Vasoactive Inotropic Score in the 48 Hours Post-LVAD Implantation Correlates with Early Severe Right Ventricular Failure

Purpose Right ventricular failure (RVF) remains a significant source of post-LVAD implantation morbidity despite advances in these mechanical circulatory support devices. The vasoactive inotropic score (VIS) is an emerging novel way to estimate total inotropic and vasotropic support, and we believe the post-operative VIS score could correlate with severe RVF post-LVAD implantation. Methods We performed a single-center retrospective study of 240 patients who received a continuous-flow durable LVAD between Jan 1st, 2006 through Dec 31st, 2017. Patients who were less than 18 years old, who underwent LVAD exchange, and who received a planned BiVAD were excluded. The VIS score was calculated as: dobutamine (mcg/kg/min) + 10 x milrinone (mcg/kg/min) + dopamine (mcg/kg/min) + 100 x epinephrine (mcg/kg/min) +100 x norepinephrine (mcg/kg/min) + 10,000 x vasopressin (mcg/kg/min). The VIS score at 6, 24, and 48 hours postoperatively were calculated and then the maximum VIS score within 48 hours for each patient used to stratify the cohort into quartiles. Severe RVF was defined as meeting clinical RVF and having inotropes >14 days after implant, RVAD placement during implant admission, or death from RVF during implant admission. Results In our 240-patient cohort, the VIS quartiles groups were 0-10, 11-15, 16-22, and 23-87. Patients in quartile 4 were older, had a higher CVP and INTERMACS level (Table 1). In our univariate analysis, quartile 4 was associated with severe RVF (OR 3.62, CI [1.37-9.56], p = 0.009). The multivariable model (which included age, INTERMACS level, total bilirubin over 2.5 mg/dL, RV dysfunction on echocardiogram, and gender) found that maximum VIS score within 48 hours for quartile 4 independently correlated with severe RVF (OR 3.04, CI [1.5 - 8.83], p = 0.04). The ROC-curve for this model had an AUC of 0.68. Conclusion Our results demonstrate that the highest VIS score within the first 48 hours after LVAD implantation correlates with severe RVF.