Usefulness of the INTERMACS scale to predict outcomes after mechanical assist device implantation

The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) scale classifies advanced heart failure patients according to hemodynamic status. This study assessed the usefulness of the INTERMACS scale to predict outcomes in advanced heart failure patients undergoing mechanical circulatory support (MCS).

Fifty-four patients underwent MCS implantation from 2001 to 2007. Group A included 27 patients at INTERMACS level 1 and 2. Group B included 27 at INTERMACS level 3 and 4. Patient characteristics pre-MCS implant, incidence of complications during support, and survival between groups were compared.

Before MCS implantation, Group A had significantly lower cardiac index, mean arterial blood pressure, systolic pulmonary pressure, higher central venous pressure, and lower urine output (p < .05). After MCS, Group A had a lower incidence of infections (17% vs 46%; odds ratio [OR], 0.25, 95% confidence interval [CI], 0.06-0.6) and a higher incidence of liver injury (39% vs 11%; OR 5, 95% CI, 1.15-25). Mortality at 30 days was higher in Group A (38% vs 11%; OR, 4.8; 95% CI, 1.1-21); however, the mortality after 30 days post-MCS support was significantly higher in Group B (0% vs 18%, p < .05). Cox model showed overall survival was poorer in Group A (hazard ratio, 2.7; 95% CI, 1.1-7).

INTERMACS levels identified patients at risk for developing complications after MCS support. INTERMACS is a valid score system that should be considered as a tool to assess patient profile and predict complications and mortality after MCS implantation.