Reduction of Microembolic Signals with a Single-Clamp Strategy in Coronary Artery Bypass Surgery: A Pilot Study

Authors

  • Hrvoje Gašparovi?
  • Branko Maloj?i?
  • Marko Borojevi?
  • Jakov Vojkovi?
  • Rajka Gabelica
  • Davor Mili?i?
  • Bojan Bio?ina

DOI:

https://doi.org/10.1532/HSF98.20091127

Abstract

Background: Neurologic deficits are perhaps the most feared form of adverse outcome following cardiac surgery. Aortic trauma generates emboli and hence harbors the potential for neurocognitive injury. The single aortic clamp strategy of coronary artery bypass grafting (CABG) aims at reducing aortic manipulation. We hypothesized that this strategy will lead to a reduction in the number microembolic signals (MES) evaluated by transcranial Doppler (TCD), a surrogate measure of cerebral embolism.

Methods: This pilot study was based on a prospective analysis of 22 patients in whom CABG was performed either with a single aortic clamp (SC group) or with a conventional multiple aortic side-clamp technique (MC group). The 2 groups did not differ with respect to mean age (60 ± 6 years versus 65 ± 8 years, not statistically significant [NS]) or EuroSCORE (2.1 ± 1.5 versus 2.9 ± 2, P = NS). The neurocognitive evaluation was based on the mini-mental state examination (MMSE). The preoperative MMSE values for the SC and MC groups were similar (29.5 ± 0.5 and 29.2 ± 1, respectively; P = NS).

Results: The total number of solid-particle embolization signals secondary to aortic manipulation was lower in the SC group than in the MC group (72 ± 28 versus 127 ± 69, P = .02). Neurocognitive performance was moderately reduced in both groups compared with preoperative values. This reduction was more pronounced in the MC group than in the SC group (22.2 ± 4.1 versus 25.3 ± 1.6, P = .02). One patient in the MC group had a reversible ischemic neurologic deficit (P = NS). There were no deaths or perioperative myocardial infarctions in either group.

Conclusions: The single-clamp CABG strategy led to a reduction in MES, indicating a less pronounced embolic burden than with the conventional side-clamp CABG strategy. This strategy translated into a better performance in postoperative neurocognitive testing in the SC group of patients.

References

Abu-Omar Y, Cader S, Guerrieri Wolf L, Pigott D, Matthews PM, Taggart DP. 2006. Short-term changes in cerebral activity in on-pump and off-pump cardiac surgery defined by functional magnetic resonance imaging and their relationship to microembolization. J Thorac Cardiovasc Surg 132:1119-25.nAranki SF, Rizzo RJ, Adams DH, et al. 1994. Single-clamp technique: an important adjunct to myocardial and cerebral protection in coronary operations. Ann Thorac Surg 58:296-302.nBar-El Y, Goor DA. 1992. Clamping of the atherosclerotic ascending aorta during coronary artery bypass operations. Its cost in strokes. J Thorac Cardiovasc Surg 104:469-74.nBarbut D, Lo YW, Gold JP, Trifiletti RR, et al. 1997. Impact of embolization during coronary artery bypass grafting on outcome and length of stay. Ann Thorac Surg 63:998-1002.nBlauth CI, Cosgrove DM, Webb BW, et al. 1992. Atheroembolism from the ascending aorta. An emerging problem in cardiac surgery. J Thorac Cardiovasc Surg 103:1104-11.nDiegeler A, Hirsch R, Schneider F, et al. 2000. Neuromonitoring and neurocognitive outcome in off-pump versus conventional coronary bypass operation. Ann Thorac Surg 69:1162-6.nDittrich R, Ringelstein EB. 2008. Occurrence and clinical impact of microembolic signals during or after cardiosurgical procedures. Stroke 39:503-11.nGhogawala Z, Westerveld M, Amin-Hanjani S. 2008. Cognitive out-comes after carotid revascularization: the role of cerebral emboli and hypoperfusion. Neurosurgery 62:385-95.nGrega MA, Borowicz LM, Baumgartner WA. 2003. Impact of single clamp versus double clamp technique on neurologic outcome. Ann Thorac Surg 75:1387-91.nGrocott HP, Yoshitani K. 2007. Neuroprotection during cardiac surgery. J Anesth 21:367-77.nHammon JW, Stump DA, Butterworth JF, et al. 2007. Coronary artery bypass grafting with single cross-clamp results in fewer persistent neuropsychological deficits than multiple clamp or off-pump coronary artery bypass grafting. Ann Thorac Surg 84:1174-8.nHoffman GM. 2006. Neurologic monitoring on cardiopulmonary bypass: what are we obligated to do? Ann Thorac Surg 81:S2373-80.nHogue CW, Gottesman RF, Stearns J. 2008. Mechanisms of cerebral injury from cardiac surgery. Crit Care Clin 24:83-98.nLynch JE, Riley JB. 2008. Microemboli detection on extracorporeal bypass circuits. Perfusion 23:23-32.nNewman S, Stygall J, Hirani S, et al. 2007. Postoperative cognitive dysfunction after noncardiac surgery: a systematic review. Anesthesiology 106:572-90.nRussell D. 2002. Cerebral microemboli and cognitive impairment. J Neurol Sci 203-204:211-4.nTsang JC, Morin JF, Tchervenkov CI, Platt RW, Sampalis J, Shum-Tim D. 2003. Single aortic clamp versus partial occluding clamp technique for cerebral protection during coronary artery bypass: a randomized prospective trial. J Card Surg 18:158-63.n

Published

2009-12-24

How to Cite

Gašparovi?, H., Maloj?i?, B., Borojevi?, M., Vojkovi?, J., Gabelica, R., Mili?i?, D., & Bio?ina, B. (2009). Reduction of Microembolic Signals with a Single-Clamp Strategy in Coronary Artery Bypass Surgery: A Pilot Study. The Heart Surgery Forum, 12(6), E357-E361. https://doi.org/10.1532/HSF98.20091127

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