Objectives: This study evaluated the effects of mechanical circulatory support (MCS) on sub-lingual microcirculation as a surrogate for splanchnic microvascular perfusion.
Methods: Between May 2008 and April 2009, 10 consecutive patients received an MCS device or extracorporeal membrane oxygenation for end-stage chronic heart failure (n = 6) or cardiogenic shock (n = 4). Microcirculation was investigated using a hand-held Sidestream Dark Field imaging device. Perfused capillary density (PCD) and capillary red blood cell velocity (cRBCv) were assessed before device implantation (T0), immediately after implantation (T1), and 1 day after implantation (T2).
Results: Median patient age was 45 years (interquartile range [IQR] 38-52 years) and 70% were men. MCS significantly decreased pulmonary capillary wedge pressure (p = 0.04). Median cardiac power index increased (0.29 [IQR, 0.21-0.34] W/m(2) at T0 vs 0.48 [IQR, 0.39-0.54] W/m(2) at T1, p = 0.005) as well as median central venous oxygen saturation (54% [IQR, 46%-61%] at T0 vs 78% [IQR, 67%-85%] at T1, p = 0.007). There was a 3-fold increase in tissue perfusion index (sub-lingual PCD x cRBCv) during mechanical circulatory support (573 [IQR, 407-693] at T0 vs 1909 [IQR, 1771-2835] at T1, p = 0.005). Microcirculatory parameters remained improved at T2.
Conclusion: Mechanical circulatory support for severe heart failure is associated with a consistent, significant, and sustained improvement in tissue perfusion, as measured at the bedside by a 2-dimensional microcirculation imaging technique.