Coronary Artery Bypass Surgery Provokes Alzheimer's Disease-Like Changes in the Cerebrospinal Fluid

Abstract

Several biomarkers are used in confirming the diagnosis of cognitive disorders. This study evaluates whether the level of these markers after heart surgery correlates with the development of cognitive dysfunction, which is a frequent complication of cardiac interventions. Concentrations of amyloid-β peptide, tau, and S100β in the cerebro-spinal fluid were assessed, as well as cognitive functions were evaluated before and after coronary artery bypass grafting, utilizing immuno-assays and psychometric tests, respectively. A drastic rise in the level of S100β was observed one week after the surgery, a mark of a severe generalized cerebral injury. The level of amyloid-β peptide significantly decreased, whereas the concentration of tau markedly increased six months postoperatively. Gradual cognitive decline was also present. These findings clearly demonstrate post-surgical cognitive impairment associated with changes in biomarkers similar to that seen in Alzheimer's disease, suggesting a unifying pathognomic factor between the two disorders. A holistic approach to coronary heart disease and Alzheimer's-type dementia is proposed.

Tau Phosphorylation and Sevoflurane Anesthesia

“…8,12,58 For instance, it is clear that sevoflurane increases tau and P-tau levels in the cerebrospinal fluid of surgical patients for at least 48 h and that some surgery, such as coronary artery bypass, also allows for increase in phosphotau, as detected in cerebrospinal fluid. 59,60 Thus, animal studies provide a tool to circumscribe instrumental factors and adapt these findings to clinical practice, at least in the choice of which anesthetic agents to be used. However, without further studies in higher mammal species, it is not currently possible to establish clear recommendations for clinical care.…”

Evaluation of Post-Surgical Cognitive Function and Protein Fingerprints in the Cerebro-Spinal Fluid Utilizing Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass-Spectrometry (SELDI-TOF MS) After Coronary Artery Bypass Grafting: Review of Proteomic Analytic Tools and Introducing a New Syndrome

“…Levels of -amyloid peptide ( AP), as well as total-tau (ttau) was shown to be elevated 1 week post-operatively, and the pattern of these biomarkers were comparable with that seen in AD 6 months after surgery, as detected by immuno-assays. These patients also demonstrated altered cytokine concentrations in their CSF, as well as poorer performance of cognitive screening tests (Rivermead) 6 months post-operatively as compared to baseline [36][37][38].…”

“…AP, t-tau, as well as some cytokines), all of which were selected because of a priori hypotheses about their role in cognitive maladies [36][37][38]. In order to expand these arbitrarily selected (and therefore limited) findings to every possible protein-marker, all CSF samples of these Institutional-Review-Board-approved studies were further re-analyzed in this report using a more global proteomics method: SELDI.…”

Developmental Disability in the Young and Postoperative Cognitive Dysfunction in the Elderly After Anesthesia and Surgery: Do Data Justify Changing Clinical Practice?

“…137 In an article titled ''Coronary artery bypass surgery provokes Alzheimer's disease-like changes in the cerebrospinal fluid,'' Palotas and colleagues found an increased τ /amyloid-β ratio in patients 6 months after surgery. 138 Results from retrospective studies remain inconclusive, but are unsettling. Examining records of 9170 veterans, Lee et al compared the risk of developing AD within 5-6 years of CABG surgery under inhalational anesthesia versus the risk of developing AD within 5-6 years of percutaneous transluminal coronary angioplasty, the latter seldom requiring general anesthesia.…”