TY - JOUR
T1 - P90: Kinetic Energy and Energy Loss in the Middle Cerebral Artery (MCA) of Heartmate II Patients
AU - Akiyama, Koichi
AU - Ji, Ruiping
AU - Clemons, Autumn
AU - Castagna, Francesco
AU - Pinsino, Alberto
AU - Cockcroft, John R.
AU - Yuzefpolsakaya, Melana
AU - Garan, Reshad
AU - Takayama, Hiroo
AU - Takeda, Koji
AU - Naka, Yoshifumi
AU - Topkara, Veli
AU - Willey, Joshua
AU - McDonnell, Barry J.
AU - Colombo, Paolo
AU - Stöhr, Eric
N1 - Abstract only
PY - 2018/12/4
Y1 - 2018/12/4
N2 - Background: In heart failure patients with continuous-flow left ventricular assist devices (CF-LVAD), arterial pulsatility in the brain is reduced and diastolic blood velocities (Vmin) are maintained. The effects of such altered hemodynamics on kinetic energy and, importantly, energy loss in the cerebral circulation have never been studied. Methods: Angle-corrected Doppler ultrasound movies of the middle cerebral artery (MCA) were recorded in 11 healthy volunteers, 5 patients with severe heart failure, and 4 patients with HM II. Data were analyzed offline using validated Vector Flow Mapping software (Cardio Flow Design, Tokyo, Japan). Vmin, pulsatility index (PI), total Energy Loss (ELAUC) and total Kinetic Energy (KEAUC) and both variables normalized for different heart rates (ELAUC/time & KEAUC/time) were calculated (Figure 1). Correlations between these energetic parameters and PI were determined. Results: PI, KEAUC and ELAUC were significantly lower in HM II (P < 0.0001 and P < 0.05) while Vmin was similar (Fig 1). Normalization of data for different heart rates (ELAUC/time & KEAUC/time) revealed the same results. PI correlated with KEAUC (logr2 = 0.33, P = 0.008) but not ELAUC (logr2 = 0.154, P = 0.087). Conclusions: ELAUC and KEAUC were significantly lower in HM II. The correlation between KEAUC and PI suggests that pulsatility may have an important impact not only on the stretch of arteries but also on the energetics of blood flow. Future studies should evaluate the clinical meaning of these observations.
AB - Background: In heart failure patients with continuous-flow left ventricular assist devices (CF-LVAD), arterial pulsatility in the brain is reduced and diastolic blood velocities (Vmin) are maintained. The effects of such altered hemodynamics on kinetic energy and, importantly, energy loss in the cerebral circulation have never been studied. Methods: Angle-corrected Doppler ultrasound movies of the middle cerebral artery (MCA) were recorded in 11 healthy volunteers, 5 patients with severe heart failure, and 4 patients with HM II. Data were analyzed offline using validated Vector Flow Mapping software (Cardio Flow Design, Tokyo, Japan). Vmin, pulsatility index (PI), total Energy Loss (ELAUC) and total Kinetic Energy (KEAUC) and both variables normalized for different heart rates (ELAUC/time & KEAUC/time) were calculated (Figure 1). Correlations between these energetic parameters and PI were determined. Results: PI, KEAUC and ELAUC were significantly lower in HM II (P < 0.0001 and P < 0.05) while Vmin was similar (Fig 1). Normalization of data for different heart rates (ELAUC/time & KEAUC/time) revealed the same results. PI correlated with KEAUC (logr2 = 0.33, P = 0.008) but not ELAUC (logr2 = 0.154, P = 0.087). Conclusions: ELAUC and KEAUC were significantly lower in HM II. The correlation between KEAUC and PI suggests that pulsatility may have an important impact not only on the stretch of arteries but also on the energetics of blood flow. Future studies should evaluate the clinical meaning of these observations.
U2 - 10.1016/j.artres.2018.10.143
DO - 10.1016/j.artres.2018.10.143
M3 - Meeting Abstract
SN - 1872-9312
VL - 24
SP - 104
EP - 105
JO - Artery Research
JF - Artery Research
IS - 1
ER -