Stable Cognition After Coronary Artery Bypass Grafting: Comparisons With Percutaneous Intervention and Normal Controls

Relationship Between Coronary Artery Revascularization and Postoperative Delirium: Progress and Perspectives

Brain dysfunction resulting from damage to the heart-brain link leads to a decline in cognitive function. This, in turn, gives rise to the clinical symptom of perioperative delirium in patients undergoing coronary artery revascularization. Those affected are provided symptomatic treatment, but many do not recover fully. Thus, medium- and long-term mortality and adverse event rates remain relatively high in patients with perioperative delirium. Despite the relatively high incidence of perioperative delirium in patients undergoing coronary artery revascularization, it has not been systematically investigated. Inflammation, vascular damage, neuronal damage, and embolism are all involved in the injury process. Here, we discuss the incidence rate, pathological mechanisms, and prognosis of delirium after coronary artery revascularization. We also discuss in detail the risk factors for delirium after coronary artery revascularization, such as anxiety, depression, mode of operation, and drug use. We hope that prevention, early diagnosis, assessment, and potential treatment can be achieved by cardiologists to improve patient prognosis.

Perceived Cognition after Percutaneous Coronary Intervention: Association with Quality of Life, Mood and Fatigue in the THORESCI Study

Purpose

Percutaneous coronary intervention (PCI) is a common invasive procedure for the treatment of coronary artery diseases. Long-term cognitive functioning after PCI and its association with health-related quality of life (HRQL) and psychological factors is relatively unknown. The aim of this study is to examine whether perceived cognitive functioning during the year after PCI is associated with HRQL over this time period, and whether mood, fatigue, and age are associated with changes in perceived cognition and HRQL.

Methods

Patients undergoing PCI (n = 384, 79% male, mean age = 63, SD = 10) were recruited in the observational Tilburg Health Outcome Registry of Emotional Stress after Coronary Intervention (THORESCI) cohort study. Perceived concentration and attention problems, HRQL, mood, and fatigue were assessed at baseline, at 1-month and 12-month follow-up.

Results

General linear mixed modeling analysis showed that across time, between- and within-subject differences in perceived concentration problems were associated with a reduced HRQL in all domains independent of clinical and demographic covariates. Only a part of this association could be explained by negative mood, fatigue, and older age. Similar findings were found for between-subject differences in perceived attention problems.

Conclusions

Between-subject differences and within-subject changes in perceived cognition in PCI patients were strongly associated with HRQL across time, such that poorer perceived cognition was associated with poorer HRQL, independent of demographic and clinical variables. Most of the associations were also independent of mood and fatigue. The results should increase the awareness of clinicians for the role of cognition in the cardiac rehabilitation and recovery post-PCI.

Cognitive decline and ischemic microlesions after coronary catheterization. A comparison to coronary artery bypass grafting

BACKGROUND

Postinterventional cognitive dysfunction (PICD) is a known complication of coronary artery bypass grafting (CABG). However, it is largely unknown whether PICD occurs after coronary catheterization.

METHODS

Neuropsychologic data were obtained from 37 patients who received coronary catheterization and 47 patients who underwent elective CABG at baseline and 3 months after the interventions. The outcomes were contrasted to 33 healthy volunteers, using analysis of covariance with baseline scores as covariates. Cerebral magnetic resonance imaging with diffusion-weighted imaging (DWI) sequences was performed in 30 catheter and 39 CABG patients 2 to 4 days after the procedures.

RESULTS

The rate of acute ischemic lesions amounted to 3.3% in the catheter group and to 17.9% in the CABG group. Postinterventional cognitive dysfunction was detected in 2 (of 10) tests in the catheter group as compared with the healthy controls (verbal memory: total recall, t = -2.61 (P = .005) and nonverbal memory, t = -2.60 [P = .005]). The CABG group showed PICD in 7 of 10 tests as compared with the healthy controls (statistics ranging from t = -1.95 [P = .027] to t = -5.14 [P < .001]). Scores of depression/anxiety and health-related quality of life were not associated with PICD (P > .05).

CONCLUSIONS

As compared with CABG, PICD and cerebral lesions appear to be substantially milder after coronary catheter intervention, but not negligible.

Vascular contributions to cognitive impairment and dementia: a statement for healthcare professionals from the american heart association/american stroke association

BACKGROUND AND PURPOSE

This scientific statement provides an overview of the evidence on vascular contributions to cognitive impairment and dementia. Vascular contributions to cognitive impairment and dementia of later life are common. Definitions of vascular cognitive impairment (VCI), neuropathology, basic science and pathophysiological aspects, role of neuroimaging and vascular and other associated risk factors, and potential opportunities for prevention and treatment are reviewed. This statement serves as an overall guide for practitioners to gain a better understanding of VCI and dementia, prevention, and treatment.

METHODS

Writing group members were nominated by the writing group co-chairs on the basis of their previous work in relevant topic areas and were approved by the American Heart Association Stroke Council Scientific Statement Oversight Committee, the Council on Epidemiology and Prevention, and the Manuscript Oversight Committee. The writing group used systematic literature reviews (primarily covering publications from 1990 to May 1, 2010), previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and, when appropriate, formulate recommendations using standard American Heart Association criteria. All members of the writing group had the opportunity to comment on the recommendations and approved the final version of this document. After peer review by the American Heart Association, as well as review by the Stroke Council leadership, Council on Epidemiology and Prevention Council, and Scientific Statements Oversight Committee, the statement was approved by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

The construct of VCI has been introduced to capture the entire spectrum of cognitive disorders associated with all forms of cerebral vascular brain injury-not solely stroke-ranging from mild cognitive impairment through fully developed dementia. Dysfunction of the neurovascular unit and mechanisms regulating cerebral blood flow are likely to be important components of the pathophysiological processes underlying VCI. Cerebral amyloid angiopathy is emerging as an important marker of risk for Alzheimer disease, microinfarction, microhemorrhage and macrohemorrhage of the brain, and VCI. The neuropathology of cognitive impairment in later life is often a mixture of Alzheimer disease and microvascular brain damage, which may overlap and synergize to heighten the risk of cognitive impairment. In this regard, magnetic resonance imaging and other neuroimaging techniques play an important role in the definition and detection of VCI and provide evidence that subcortical forms of VCI with white matter hyperintensities and small deep infarcts are common. In many cases, risk markers for VCI are the same as traditional risk factors for stroke. These risks may include but are not limited to atrial fibrillation, hypertension, diabetes mellitus, and hypercholesterolemia. Furthermore, these same vascular risk factors may be risk markers for Alzheimer disease. Carotid intimal-medial thickness and arterial stiffness are emerging as markers of arterial aging and may serve as risk markers for VCI. Currently, no specific treatments for VCI have been approved by the US Food and Drug Administration. However, detection and control of the traditional risk factors for stroke and cardiovascular disease may be effective in the prevention of VCI, even in older people.

CONCLUSIONS

Vascular contributions to cognitive impairment and dementia are important. Understanding of VCI has evolved substantially in recent years, based on preclinical, neuropathologic, neuroimaging, physiological, and epidemiological studies. Transdisciplinary, translational, and transactional approaches are recommended to further our understanding of this entity and to better characterize its neuropsychological profile. There is a need for prospective, quantitative, clinical-pathological-neuroimaging studies to improve knowledge of the pathological basis of neuroimaging change and the complex interplay between vascular and Alzheimer disease pathologies in the evolution of clinical VCI and Alzheimer disease. Long-term vascular risk marker interventional studies beginning as early as midlife may be required to prevent or postpone the onset of VCI and Alzheimer disease. Studies of intensive reduction of vascular risk factors in high-risk groups are another important avenue of research.

Improvement of cognitive test performance in patients undergoing primary CABG and other CPB-assisted cardiac procedures

Cardiac surgical procedures assisted by cardiopulmonary bypass (CPB) impair cognitive functions. Several studies, however, showed that cognitive functions were unaffected in patients undergoing either primary coronary artery bypass grafting (CABG) or more complex surgery assisted by CPB. Therefore, we conducted a straightforward study to compare patient groups who differed significantly in terms of risk factors such as prolonged CPB times. Consecutive patients (n = 54) were included, undergoing either non-primary CABG, e.g. valve and/or CABG, (n = 30) or primary CABG (n = 24), assisted by CPB. Cognitive function was determined pre-operatively on the day of hospital admission, and post-operatively after one and six months using the Cognitive Drug Research computerized assessment battery. Data from the fourteen individual task variables were summarized in four composite scores: Power of Attention (PoA), Continuity of Attention (CoA), Quality of Episodic Memory (QoEM), and Speed of Memory (SoM). In the non-primary CABG patients, both CoA and QoEM improved after 1 month (p = 0.001 and p = 0.016, respectively), whereas, after 6 months, CoA (p = 0.002), QoEM (p = 0.002) and SoM (p < 0.001) were improved. In primary CABG patients, CoA improved at one month after surgery (p = 0.002) and, after six months, not only CoA (p = 0.003), but also QoEM and SoM were improved (p = 0.001 and p = 0.030, respectively). The test performance was similar in non-primary and primary CABG patients after surgery. Our present study shows a post-operative improvement of cognitive composite scores after cardiac surgery assisted by CPB in both non-primary CABG and in primary CABG patients.

Cognitive outcomes five years after not undergoing coronary artery bypass graft surgery

BACKGROUND

Patients with coronary artery disease who underwent coronary artery bypass graft surgery have a high risk of cognitive decline 5 years after the procedure. It is conceivable that this is not caused by the operation, but by natural aging.

METHODS

Psychologists repeatedly administered a battery of seven neuropsychological tests with eight main variables to 112 subjects without known coronary artery disease, with a time interval of 5 years. Cognitive decline was defined as deterioration in performance beyond normal variation in at least two of the eight main variables. The incidence of cognitive decline in the control subjects was compared with the incidence of cognitive decline in the 281 participants of the Octopus Study, who underwent coronary artery bypass graft surgery 5 years earlier. Patients and control subjects were age-matched.

RESULTS

After 5 years, cognitive outcome could be determined in 99 of 112 control subjects (88%) and 240 of 281 coronary artery bypass graft surgery patients (85%). Cognitive decline was present in 82 (34.2%) of 240 coronary artery bypass graft surgery patients and in 16 (16.2%) of 99 control subjects (crude odds ratio, 2.69; 95% confidence interval, 1.48 to 4.90). However, after correction for differences in age, sex, education, and baseline comorbidity between the patients and the control subjects, the odds ratio was 1.37 (95% confidence interval, 0.65 to 2.92).

CONCLUSIONS

We were unable to demonstrate that patients who underwent coronary artery bypass graft surgery have more cognitive decline after 5 years than control subjects without coronary artery disease.

The Cardiotomy Trial

Background— Reinfusion of unprocessed cardiotomy blood during cardiac surgery can introduce particulate material into the cardiopulmonary bypass circuit, which may contribute to postoperative cognitive dysfunction. On the other hand, processing of this blood by centrifugation and filtration removes coagulation factors and may potentially contribute to coagulopathy. We sought to evaluate the effects of cardiotomy blood processing on blood product use and neurocognitive functioning after cardiac surgery.

Methods and Results— Patients undergoing coronary and/or aortic valve surgery using cardiopulmonary bypass were randomized to receive unprocessed blood (control, n=134) or cardiotomy blood that had been processed by centrifugal washing and lipid filtration (treatment, n=132). Patients and treating physicians were blinded to treatment assignment. A strict transfusion protocol was followed. Blood transfusion data were analyzed using Poisson regression models. The treatment group received more intraoperative red blood cell transfusions (0.23±0.69 U versus 0.08±0.34 U, P =0.004). Both red blood cell and nonred blood cell blood product use was greater in the treatment group and postoperative bleeding was greater in the treatment group. Patients were monitored intraoperatively by transcranial Doppler and they underwent neuropsychometric testing before surgery and at 5 days and 3 months after surgery. There was no difference in the incidence of postoperative cognitive dysfunction in the 2 groups (relative risk: 1.16, 95% CI: 0.86 to 1.57 at 5 days postoperatively; relative risk: 1.05, 95% CI: 0.58 to 1.90 at 3 months). There was no difference in the quality of life nor was there a difference in the number of emboli detected in the 2 groups.

Conclusions— Contrary to expectations, processing of cardiotomy blood before reinfusion results in greater blood product use with greater postoperative bleeding in patients undergoing cardiac surgery. There is no clinical evidence of any neurologic benefit with this approach in terms of postoperative cognitive function.