Cerebral vein thrombosis after coronary artery bypass surgery

A case of cerebral vein thrombosis after cardiac artery bypass grafting is presented in a patient with coronary artery disease and prolonged angina. Postoperatively he failed the weaning trials because of brain dysfunction characterized by confusion, agitation and hyperpnea. He was initially considered to represent a typical case of post cardiac surgery brain underperfusion, but as he later developed persistent signs of endocranial hypertension, imaging of the brain vessels was carried out revealing obstruction of the left transverse and the frontal half of the oblique sinus. The patient was treated with anticoagulation and cerebrospinal fluid drainage through a lumbo-peritoneal shunt. He was discharged from the ICU in good condition after 102 days of hospitalization. As magnetic resonance imaging of the brain is generally recommended in cases with post cardiac surgery brain dysfunction with normal computed tomography scan, adding magnetic resonance phlebography to the examination protocol seems rational.     

Neurocognitive dysfunction after coronary artery bypass surgery: a systematic review

OBJECTIVE: Substantial, albeit scattered, evidence suggests that coronary artery bypass grafting may impair cognitive function. As methods and definitions differ greatly across studies, the reported incidence of cognitive decline after coronary bypass surgery varies widely as well. The aim of the present study was to systematically review those studies on cognitive decline that are relatively comparable and meet with certain quality criteria. METHODS: Four electronic databases and the references of several abstract books and earlier reviews were used to identify relevant literature. Stringent criteria, based in part on the 1994 consensus meeting on assessment of neurobehavioral outcomes after cardiac surgery, were used to assess the studies that were found. In total, 256 different titles were found, of which 23 met with the formulated selection criteria. RESULTS: Twelve cohort studies and eleven intervention studies were evaluated. A pooled analysis of six highly comparable studies yielded a proportion of 22.5% (95% confidence interval, 18.7%-26.4%) of patients with a cognitive deficit (a decrease of at least 1 standard deviation in at least two of nine or ten tests) 2 months after the operation. CONCLUSIONS: Neurocognitive dysfunction is a frequently occurring complication of coronary artery bypass grafting. The etiologic contribution of cardiopulmonary bypass to this complication will remain unclear until a randomized trial that directly compares off-pump and on-pump bypass surgery is carried out.     

Silent left ventricular dysfunction during exercise after coronary artery bypass surgery

Serial changes in left ventricular function during exercise were assessed by radionuclide continuous ventricular function monitoring in 80 patients undergoing coronary artery bypass surgery before and after operation. This monitor records serial beat by beat radionuclide and electrocardiographic data and calculates the left ventricular ejection fraction every 20s. The profiles of ejection fractions during graded bicycle exercise were divided into 4 types. In type A, the ejection fraction continued to increase. In type B, the ejection fraction initially increased but decreased in late exercise. In type C, the ejection fraction did not change. In type D, the ejection fraction continued to decrease. Type A is considered to be the normal response to exercise and types B, C and, D are considered to be abnormal responses. Before operation, 8 patients showed type A, 21 type B, 13 type C, and 38 type D. After operation, 53 patients showed type A, 16 type B, 8 type C, and 3 type D. The mean ejection fraction decreased with exercise from 53%±11% to 47%±11% before surgery, but increased with exercise from 55%±10% to 64%±14% after surgery. During postoperative exercise, no patient developed chest pain but 19 patients showed a decrease in the ejection fraction in early or late exercise. A decrease in the ejection fraction is an earlier indicator of myocardial ischaemia than angina or electrocardiographic changes. Silent left ventricular dysfunction during postoperative exercise was considered to reflect myocardial ischaemia resulting from occluded grafts, ungrafted coronary arteries, or inadequate perfusion by arterial grafts. The radionuclide continuous ventricular function monitor can detect silent left ventricular dysfunction after coronary artery bypass surgery.     

Aortic atheroma burden and cognitive dysfunction after coronary artery bypass graft surgery

Background

Neurocognitive dysfunction (NCD) after coronary artery bypass graft (CABG) surgery is a common problem. Atherosclerotic disease of the aorta is a known risk factor for stroke after cardiac surgery, but its relationship to NCD is unclear. This study investigates the relationship between aortic atherosclerotic disease and NCD after CABG.

Patients and Methods

Patients undergoing primary elective CABG were enrolled in an ongoing investigation of NCD after CABG. Intraoperative transesophageal echocardiography (TEE) of the thoracic aorta was performed and analyzed off-line to quantify atheroma burden. Neurocognitive evaluation was performed, both preoperatively and at 6 weeks after surgery. Multivariable linear regression (controlling for age, years of education, and base line cognitive index) was used to determine the relationship between NCD and atheroma burden in the ascending, arch, and descending aorta.

Results

One hundred sixty-two patients who had a complete neurocognitive evaluation and adequate TEE images were studied. No significant relationship was found between NCD and atheroma burden in the ascending (p = 0.22), arch (p = 0.89) or descending aorta (p = 0.64).

Conclusions

Although the etiology of NCD is likely multifactorial, our results suggest that aortic atherosclerosis may not be the primary factor in the pathogenesis of post-CABG cognitive changes.     

Delirium after coronary artery bypass surgery.

The incidence of postoperative delirium following coronary artery bypass surgery was 28%. This rate is comparable to that after open-heart surgery. However, of those variables which were previously found to correlate with delirium in the open-heart group, only severity of postoperative illness in the recovery room significantly correlated with delirium in patients having bypass. The relationship between personality type and delirium, previously found to be signficant, was suggestively associated in these patients. A history of myocardial infarction prior to surgery was significantly associated with delirium.     

The effect of lidocaine on early postoperative cognitive dysfunction after coronary artery bypass surgery

We investigated the effect of lidocaine on the incidence of cognitive dysfunction in the early postoperative period after cardiac surgery. One-hundred-eighteen patients undergoing elective coronary artery bypass surgery with cardiopulmonary bypass (CPB) were randomized to receive either lidocaine (1.5 mg/kg bolus followed by a 4 mg/min infusion during operation and 4 mg/kg in the priming solution of CPB) or placebo. A battery of nine neuropsychological tests was administered before and 9 days after surgery. A postoperative deficit in any test was defined as a decline by more than or equal to the preoperative SD of that test in all patients. Any patient showing a deficit in two or more tests was defined as having postoperative cognitive dysfunction. Eighty-eight patients completed pre- and postoperative neuropsychological tests. Plasma lidocaine concentrations (microg/mL) were 4.78 +/- 0.52 (mean +/- SD), 5.38 +/- 0.95, 4.52 +/- 0.39, 5.82 +/- 0.76, and 7.10 +/- 1.09 at 10 min before CPB; 10, 30, and 60 min of CPB; and at the end of operation, respectively. The proportion of patients showing postoperative cognitive dysfunction was significantly reduced in the lidocaine group compared with that in the placebo group (18.6% versus 40.0%; P = 0.028). We conclude that intraoperative administration of lidocaine decreased the occurrence of cognitive dysfunction in the early postoperative period. IMPLICATIONS: Postoperative cognitive dysfunction is a commonly recognized complication after cardiac surgery. Intraoperative cerebral microembolism and hypoperfusion have been proposed to be the major mechanisms. The results of this study show that intraoperative administration of lidocaine decreased the occurrence of early postoperative cognitive dysfunction, perhaps because of its neuroprotective effects.     

Breast reduction surgery after coronary artery bypass grafting

Breast reduction surgery is a frequently performed procedure. Older patients presenting for this surgery may have previously undergone coronary artery bypass grafting with harvesting of one or both internal mammary arteries. This may compromise the blood supply to the breast. Limiting medial dissection during breast reduction surgery in these women is prudent to prevent breast necrosis. A case illustrating this is described.     

Autoimmune myasthenia gravis after coronary artery bypass surgery

We report a rare case of spontaneous dissection of an anomalous systemic artery supplying a normal basal segment of the right lung during pregnancy, leading to recurrent hemoptysis. This article aims to discuss the clinical presentation, diagnostic curiosity, management using a minimally invasive technique (video-assisted thoracoscopic lobectomy), and finally the histopathologic findings.     

Cerebral blood flow and cognitive dysfunction after coronary surgery

BACKGROUND: Postoperative cognitive dysfunction after cardiac surgery has been attributed both to embolic events and periods with reduced cerebral perfusion. We investigated whether cognitive dysfunction after coronary surgery is associated with changes in regional cerebral blood flow (CBF) using single photon emission computed tomography. METHODS: Before surgery and at discharge, 15 coronary surgery patients were studied. Global and regional CBF were measured using a brain-dedicated single photon emission computed tomography scanner, and neuropsychological testing with seven subtests was performed. Postoperative cognitive dysfunction was defined as a Z score above 2. Normative single photon emission computed tomography data were available from 26 healthy age-matched controls. RESULTS: Preoperative global CBF was significantly lower in patients compared with controls (53.7 versus 46.1 mL/100 g/min, p = 0.006). After surgery, global CBF significantly decreased in the patient group (46.1 versus 38.6 mL/100 g/min, p = 0.0001). No significant differences were detected in regional CBF. Cognitive dysfunction was identified in 4 of the 15 patients (26.7%, 95% CI 7.8% to 55.1%). No correlation was found between the neuropsychological Z score and global or regional CBF. CONCLUSIONS: The significant decrease in CBF after coronary surgery was uniformly distributed and was not correlated to postoperative cognitive dysfunction.     

Off-pump versus on-pump coronary artery bypass surgery and postoperative renal dysfunction

Renal dysfunction is a serious complication after coronary bypass surgery with cardiopulmonary bypass (CABG). Because duration of cardiopulmonary bypass (CPB) is associated with renal outcome, it has been proposed that avoidance of CPB with off-pump coronary bypass (OPCAB) may reduce perioperative renal insult. We therefore tested the hypothesis that OPCAB is associated with less postoperative renal dysfunction compared with CABG surgery. With IRB approval, we gathered data for 690 primary elective coronary bypass patients (OPCAB, 55; CABG, 635). Perioperative change in creatinine clearance (DCrCl) was calculated by using preoperative (CrPre) and peak postoperative (CrPost) serum creatinine values, and the Cockroft-Gault equation (DCrCl = CrPreCl - CrPostCl). Univariate and linear multivariate tests were used in this retrospective analysis; P: < 0.05 was considered significant. Multivariate analysis did not identify OPCAB surgery as an independent predictor of DCrCl. However, previously reported associations of PreCrCl, age, and diabetes with DCrCl were confirmed. Power analysis demonstrated an 80% power to detect a 7.0 mL/min DCrCl difference between study groups. In this retrospective study, we could not confirm that OPCAB significantly reduces perioperative renal dysfunction compared with CABG surgery. Our findings suggest that reduction of renal risk alone should not be an indication for OPCAB over CABG surgery. Implications: Retrospective analysis did not identify any significant difference in perioperative change in creatinine clearance after coronary revascularization with cardiopulmonary bypass compared with off-pump coronary surgery.     

Off-pump coronary artery bypass surgery in the left ventricular dysfunction.

OBJECTIVE: The purpose of this study is to report our experience in off-pump coronary artery surgery in patients who have left ventricular dysfunction. METHODS: Off-pump coronary artery surgery was performed to 48 patients who were chosen randomly among 265 patients having two or more coronary artery disease and whose ejection fraction (EF) was less than 30%. In these patients fractioned shortening (FS) was evaluated by echocardiography, EF with multiple gated acquisition (MUGA) and ischaemic regions with myocardial perfusion scintigraphy both pre- and postoperatively. Coronary artery angiography was done to all patients at the end of the 1st year and patients were evaluated according to New York Heart Association (NYHA) classification. RESULTS: There were three deaths. The clinical situations of 41 of 45 patients (91.1%) improved after the operation. These four patients who didn't improve in NYHA status were the ones in whom complete revascularization couldn't be done. The FS and EF values were significantly increased at the 1st month, and 1st year. The constant perfusion defects and irreversible damaged areas changed into dynamic myocardial tissue in the 1st year scintigraphies. DISCUSSION: Off-pump CABG can be done with an acceptable mortality and clinic results in patients who have ventricular dysfunction.     

Off-pump versus on-pump coronary artery bypass surgery and postoperative pulmonary dysfunction

OBJECTIVE: To investigate how off-pump coronary artery bypass grafting (CABG) affects postoperative pulmonary function when compared with on-pump CABG. DESIGN: Prospective clinical study. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Adult patients (n = 39) undergoing elective coronary artery bypass surgery with or without cardiopulmonary bypass. INTERVENTIONS: Two groups of patients were compared: 19 consecutive patients undergoing off-pump CABG surgery and 20 consecutive patients undergoing conventional CABG surgery. MEASUREMENTS AND MAIN RESULTS: Pulmonary function tests (flow volume loops and lung volumes with plethysmography) were done preoperatively and 72 hours postoperatively. Arterial blood gases and PaO2/FIO2 were measured at various stages. Sequential chest x-rays were obtained and evaluated for pleural changes, pulmonary edema, and atelectasis. In both groups, PaO2/FIO2 ratios decreased progressively throughout the perioperative period, with no significant differences between the groups at any stage during the study. There was a significant decline in postoperative pulmonary function tests in both groups, but there was no difference between groups at 72 hours postoperatively. No differences were found in the time to extubation, atelectasis scores, or postoperative complications. CONCLUSIONS: Off-pump CABG does not confer major protection from postoperative pulmonary dysfunction compared with CABG surgery with CPB. Strategies for minimizing pulmonary impairment after CABG surgery should be directed to factors other than the use of CPB.     

老年病人冠状动脉搭桥术后神经功能障碍的初步探讨

目的：通过对冠状动脉搭桥（CABG）术中进行经颅脑氧饱和度（TCCO）和经颅多谱勒（TCD）监测，探讨老年病人CABG术中局部脑氧饱和度（rSO2)和大脑中动脉微栓数量（HITS）的变化与术后神经功能障碍的关系。方法：择期CABG手术358例，根据年龄为Ⅰ组（年龄≥60岁）和Ⅱ组（年龄＜60岁，术中使用TCCO和TCD持续监测rSO2和HITS，术后随访进行神经功能的检查和评估。结果：本组病人术后神经功能障碍发病率14％，其中I组为18．7％，Ⅱ组为6％，I组明显高于Ⅱ组（P＜0．05），同时I组的术后清醒时间，气管拔管时间，ICU时间，住院时间和住院死亡率也明显高于Ⅱ组，低rSO2的发病率为25．4％，其中I组为30．2％，Ⅱ组为17．3％，I组明显高于Ⅱ组（P＜0．05），而术中I组和Ⅱ组的HITS无明显差别（P＞0．05）。结论：老年病人术后神经功能障碍发病率高，与术前合并并脑血管病等危险因素和术中低rSO2发生率高有关，而与HITS的绝大数量无关。引起低rSO2的原因可能与低灌注，脑氧供／氧耗失衡，或低灌注和栓塞多种因素共同作用所致。