(A) Impella patient: Impella patients had morphologically distinct pulsatile waveforms compared to other types of ventricular assist devices. (B) Intra-arterial balloon pump (IABP) patient: Pronounced diastolic upstrokes not present in other devices, with evidence of unsupported systolic peak, inflation point, augmented diastole, and unassisted diastole. (C) Total artificial heart (TAH) patient: Waveforms resemble hemodynamics of unassisted patient.
IABP = intra-arterial balloon pump; LMCA = left middle cerebral artery; RMCA = right middle cerebral artery; TAH = total artificial heart; TCD = transcranial Doppler; Peak = peak systolic velocity; Dias = diastolic velocity; Mean = mean flow velocity; P.I. = pulsatility index.