Abstract
Left ventricular assist devices (LVADs) have become more important than ever for patients with terminal heart disease. The chronic shortage of donors for heart transplantation may enhance the importance of LVADs as destination therapy. To prevent cerebral complications, the evaluation of high-intensity transient signals (HITS) of transcranial Doppler (TCD) ultrasound is important. In the present study, HITS were measured on seven occasions in patients supported with LVADs. The high-frequency counts in HITS were greater than the low-frequency counts (47 ± 42 vs. 9 ± 9 in 3 min, P = 0.025), and declined further with oxygen delivery to the patient. The high frequency of signals may imply air microemboli, and the counts may increase with time.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abu-Omar Y, Balacumaraswami L, Pigott DW, Matthews PM, Taggart DP. Solid and gaseous cerebral microembolization during off-pump, on-pump, and open cardiac surgery procedures. J Thorac Cardiovasc Surg 2004;127:1759–1765
Stevenson LW, Miller LW, Desvigne-Nickens P, Ascheim DD, Parides MK, Renlund DG, Oren RM, Krueger SK, Costanzo MR, Wann LS, Levitan RG, Mancini D; REMATCH Investigators. Left ventricular assist device as destination for patients undergoing intravenous inotropic therapy. Circulation 2004;110:975–981
Takano H, Nakatani T. Ventricular assist systems: experience in Japan with the Toyobo pump and the Zeon pump. Ann Thorac Surg 1996;61:317–322
Consensus Committee of the Ninth International Cerebral Hemodynamics Symposium. Basic identification criteria of Doppler microembolic signals. Stroke 1995;26:1123
Hanzawa K, Ohzeki H, Hayashi J. Frequency analysis of high-intensity transient signals in CPB distinguish solid embolic signals from gaseous signals. Ann Thorac Surg 1998;66:1490 (abstract)
Thoennissen NH, Schneider M, Allroggen A, Ritter M, Dittrich R, Schmid C, Scheld HH, Ringelstein EB, Nabavi DG. High level of cerebral microembolization in patients supported with the DeBakey left ventricular assist device. J Thorac Cardiovasc Surg 2005;130:1159–1166
Thoennissen NH, Allroggen A, Ritter M, Dittrich R, Schmid C, Schmid HH, Ringelstein EB, Nabavi DG. Influence of inflammation and pump dynamic on cerebral microembolization in patients with continuous-flow DeBakey LVAD. ASAIO J 2006;52:243–247
Potapov EV, Nasseri BA, Loebe M, Kukucka M, Koster A, Kuppe H, Noon GP, DeBakey ME, Hetzer R. Transcranial detection of microembolic signals in patients with a novel nonpulsatile implantable LVAD. ASAIO J 2001;47:249–253
Hanzawa K, Kitamura M, Ohzeki H, Hayashi J. Anticoagulants reduced high-intensity transient signals (HITS) during LVAD use. J Congestive Heart Failure and Circulatory Support2001;1:387–390
Nabavi DG, Stockmann J, Schmid C, Schneider M, Hammel D, Scheld HH, Ringelstein EB. Doppler microembolic load predicts risk of thromboembolic complication in Novacor patients. J Thorac Cardiovasc Surg 2003;126:160–167
Author information
Authors and Affiliations
Additional information
Presented in part at the 2007 Joint Congress of the 45th Annual Conference of the Japanese Society for Artificial Organs and the 2nd Annual Conference of the International Federation for Artificial Organs, Osaka
Rights and permissions
About this article
Cite this article
Sato, K., Hanzawa, K., Okamoto, T. et al. Frequency analysis of high-intensity transient signals of transcranial Doppler ultrasound in patients supported with a left ventricular assist device. J Artif Organs 11, 201–203 (2008). https://doi.org/10.1007/s10047-008-0430-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10047-008-0430-7