The role of asymmetry and the nature of microembolization in cognitive decline after heart valve surgery: a pilot study

Abstract

Our objective was to determine the role of asymmetry and the nature of microembolization on postoperative cognitive decline in patients who had undergone heart valve surgery. Continuous transcranial Doppler ultrasound was intraoperatively used for both middle cerebral arteries in 13 right-handed heart valve surgery patients to detect microembolization. The Trail Making Test A and B, Memory with 10/30 s interference, the Digit Span Test and Phonemic Fluency were performed preoperatively, at discharge and three months after surgery. Our data suggest that early and late postoperative psychomotor and executive functions may be sensitive to microemboli in the left, but not in the right middle cerebral artery. Moreover, solid and gaseous microemboli are both similarly associated with early postoperative cognitive decline while, surprisingly, late postoperative cognitive decline is more likely to be associated with gaseous than solid microemboli.

Effects of Ncl. Basalis Meynert volume on the Trail‐Making‐Test are restricted to the left hemisphere

“…Although the attention network has been thought to be right-lateralized, activation in circumscribed regions in left frontal and parietal areas has been attributed to several subdomains of visual search (Weidner et al 2009). Additionally, performance in the TMT has been found to be specifically affected by hypoperfusion of the left hemisphere, which is in line with our finding of the left CH4 region specifically affecting TMT performance Zanatta et al 2012).…”

“…During inspection of partial regression plots we found evidence for a quadratic rather than a linear effect of the left CH4 volume on performance in the TMT Part A and B. Referring to a report on the finding that hypoperfusion of the left hemisphere is associated with postoperative low performance in the Trail-Making-Test, we considered a focus on this subregion appropriate Zanatta et al 2012). Holley et al (1995) modulated the activity of cholinergic basal forebrain cells in a rat model of sustained attention using a GABA A -receptor antagonist.…”

Digital reconstruction and morphometric analysis of human brain arterial vasculature from magnetic resonance angiography

“…Further, we demonstrate how the existing analysis methods can be used to study individual and population differences in cerebral vasculature at the level of the entire vasculature, specific arteries or single branches. Age-related changes, hemispheric lateralization, and gender-related difference in cerebral circulation may all be important risk factors in cerebrovascular disorders (Zanatta et al, 2012; Zurada et al, 2011). For instance, increase in tortuosity of right arterial trees during normal aging may have clinical implications (Zurada et al, 2010, 2011), while higher rate of subarachnoid hemorrhages in women may be caused by hormonal differences (Ghods et al, 2012).…”

Are patient- or procedure-related factors relevant to middle-term cognitive decline after cardiac surgery? This is the question

“…1 Cognitive decline at discharge from the hospital, namely, short-term POCD, is mainly due to procedure-related factors, such as cerebral hypoperfusion and microembolization associated with the duration of cardiopulmonary bypass (CPB). 2 Conversely, long-term (≥1 year) POCD is more likely to be ascribed to patient- rather than procedure-related factors, such as low educational level, pre-existing cerebrovascular disease, cognitive impairment or dep-ression. 1,3 Among these factors, it has been shown that pre-existing cognitive impairment plays a key role in long-term cognitive decline after surgery.…”

“…The latter period of time is particularly interesting given that there is evidence that it is influenced by both patient- and procedure-related factors. 2,5 Importantly, the three-month follow-up is also critical for postsurgical recovery given that it has been indicated as the first time interval for post-convalescent assessment relevant to postoperative cognitive outcome. 6 Therefore, after local ethics committee approval, we examined the influence of such factors on cognitive decline at middle-term follow-up in 79 patients who were admitted for first-time elective cardiac surgery with CPB and gave their informed written consent (for the characteristics of the sample, see Ref.…”