Strategy for the reduction of stroke incidence in cardiac surgical patients

Toward stroke-free coronary surgery: The role of the anaortic off-pump bypass technique

Surgical coronary revascularization remains the preferred strategy in a significant portion of patients with coronary artery disease due to superior long-term outcomes. However, there is a significant risk of perioperative neurologic injury that has influenced guideline recommendations. These complications occur in 1%-5% of patients, ranging from overt neurologic deficits with permanent disability, to subtle cerebral defects noted on neuroimaging that may result in slow cognitive and functional decline. The primary mechanism by which these events occur is thromboembolism from manipulation of the ascending aorta. This occurs during cardiopulmonary bypass, aortic cross-clamping, and partial occlusion clamping (side clamp). Elderly patients and patients with aortic atheroma are, therefore, at significantly increased risk. Initial surgical techniques addressed this by aggressively debriding or replacing the ascending aorta during coronary artery bypass grafting (CABG). Strategies then moved toward minimizing aortic manipulation through pump-assisted beating heart surgery and off-pump surgery with partial occlusion clamping or proximal anastomosis devices. Finally, anaortic off-pump CABG aims to avoid all manipulation of the ascending aorta through advanced off-pump grafting techniques combined with in situ and composite grafts. This has been demonstrated to result in the greatest reduction in risk. Establishing successful anaortic off-pump CABG programs requires subspecialization and focused interest groups dedicated to advancing CABG outcomes.

Review of cerebral perfusion strategies for aortic surgery with application for minimally invasive approaches

Aortic arch and hemiarch surgery necessitate the temporary interruption of blood perfusion to the brain. Despite its complexity, hemiarch and ascending aortic surgery can be performed via a minimally invasive approach. Due to the higher risk of neurological injury during a circulatory arrest, several techniques were developed to further protect the brain during this surgery. We searched the Embase, Medline, and Cochrane databases and identified articles reporting outcomes of antegrade and retrograde cerebral perfusion strategies. Herein, we outline surgical approaches, intra-operative technical considerations, and clinical outcomes of hemiarch and ascending aortic surgery. Hemiarch and ascending aortic surgery is associated with a higher risk of mortality and morbidity. Attention to the optimal approach and cerebral protection strategy has been shown to significantly affect outcomes and mitigate risk.

Contemporary Management of Patients with Concomitant Coronary and Carotid Artery Disease

The ideal management of concomitant carotid and coronary artery occlusive disease remains elusive. Although researchers have advocated the potential benefits of varying treatment strategies based on either concomitant or staged surgical treatment, there is no consensus in treatment guidelines among national or international clinical societies. Clinical studies show that coronary artery bypass grafting (CABG) with either staged or synchronous carotid endarterectomy (CEA) is associated with a high procedural stroke or death rate. Recent clinical studies have found carotid artery stenting (CAS) prior to CABG can lead to superior treatment outcomes in asymptomatic patients who are deemed high risk of CEA. With emerging data suggesting favorable outcome of CAS compared to CEA in patients with critical coronary artery disease, physicians must consider these diverging therapeutic options when treating patients with concurrent carotid and coronary disease. This review examines the available clinical data on therapeutic strategies in patients with concomitant carotid and coronary artery disease. A treatment paradigm for considering CAS or CEA as well as CABG and percutaneous coronary intervention is discussed.

Does epiaortic ultrasound screening reduce perioperative stroke in patients undergoing coronary surgery? A topical review

Although the occurrence of stroke in patients undergoing coronary artery bypass grafting (CABG) is decreasing, it remains an important concern. Therefore, it is important to identify and adopt strategies that can decrease the incidence of stroke in these patients. One of the strategies that have demonstrated the potential to decrease the rate of post-CABG stroke is an assessment of aorta for atherosclerosis before surgery and changing the surgical plan accordingly to minimize the stroke risk. This assessment can be done through palpation of the aorta, transesophageal echocardiography (TEE), and epiaortic ultrasound scanning (EAS). EAS has shown superiority over both palpation and TEE for intraoperative evaluation of aorta. However, despite the evidence demonstrating reduced stroke rates with the EAS-guided approach, EAS is not yet the standard of care procedure in patients undergoing CABG. Therefore, we have reviewed the literature for evidence that supports the routine use of EAS in patients undergoing coronary surgery and have presented solutions to overcome the barriers to its routine use.

Perioperative stroke - Prediction, Prevention, and Protection

Stroke culminates into 6.2 million deaths annually and is thereby a leading cause of disability and death worldwide. In patients undergoing noncardiac, nonneurological surgery, perioperative stroke can eventuate into a catastropic aftermath with almost eight-fold rise in mortality. In cardiac, neurological, and carotid surgery, stroke rate accounts to be high (2.2%–5.2%) and is a significant instigator of morbidity and mortality as well. These facts kindle interest to review the predictive parameters, preventive measures, and all the possibilities in the management and protection against perioperative stroke.

Strategies to Protect the Brain During Cardiac Surgery

Despite significant advances in cardiopulmonary by pass (CPB) technology, surgical techniques, and anes thetic management, central nervous system (CNS) com plications remain a common and costly problem after CPB. Stroke is often considered a rare and unprevent able complication of cardiac surgery. Recent studies have shown that through the use of echocardiography and historical risk stratification strategies, we can de fine which patients are at substantially greater risk for CNS injury. Through enhanced understanding of the etiology of stroke and perioperative factors, which are associated with potential for neuroprotection or injury extension, there now exists a greater potential than ever to substantially reduce neurological injury associ ated with cardiac surgery. Strategies and theories of stratifying patients at risk and secondarily reducing that risk are described, as well as consideration for early postoperative assessment to allow treatment when events occur.

Bad aorta

As its outcomes improve, cardiac surgery has been performed on more and more cases which were previously considered to be difficult to deal with. However, there are still a number of problems to be solved regarding surgery on patients with severe sclerotic lesions in the ascending aorta, which we collectively call "bad aorta". Concerning a preoperative assessment of the ascending aorta, our report revealed no relationship between the severity of calcification detected with a preoperative non-enhanced CT and the aortic lesion found during the surgery. Meanwhile, an intraoperative epiaortic ultrasound enables us to make high-quality evaluations of the aorta without imposing much burden on the patient. This modality may be essential for cardiac surgery. As for surgical management for bad aorta, quite a few methods have been reported to this point, but the overall operative mortality rate and cerebrovascular accident rate are relatively high, at a little <10 %, respectively. With the recent cross-clamping method under short-term total circulatory arrest (TCA), however, the results are much better; these rates total around 5 %. Further improvement is expected in the outcome of cardiac surgery on bad aorta cases by establishing a modality to evaluate sclerotic lesions in the ascending aorta with epiaortic ultrasound and by selecting a proper procedure for each case.

Floating mass in the aortic arch: An interesting case report

The finding of a floating mass in the aortic arch is rare and the management remains controversial. The gold standard for visualization of atheromatic plaque is computed tomography scanning. However, in some patients transthoracic harmonic imaging from a suprasternal window can reliably visualize protruding aortic arch atheromas, thus making an excellent screening test. We report a case of a ruptured floating atheromatous aortic plaque in a 77-year-old man with severe aortic valve stenosis and known coronary artery disease presenting with progressing dyspnea. Both procedures, atheromatic plaque removal and aortic valve replacement, were undertaken during the same surgical operation, which was completed with success and the patient was discharged in a good state of health. <Learning objective: The management of a patient suffering from both aortic valve stenosis and a pedunculated aortic plaque remains a challenge. It seems to be the only way to remove the plaque before replacing the aortic valve in order to avoid a possible embolism. A strong association between aortic stenosis and aortic atherosclerosis has recently been established. Finally, this case emphasizes the importance of suprasternal echocardiographic view in the diagnosis of a pedunculated mass in the aortic arch.>.

The results of the enclose II proximal anastomotic device in 178 off-pump coronary artery bypass surgeries

OBJECTIVE

Enclose II is a new device for proximal coronary artery bypass anastomoses. We evaluated the safety and effectiveness of Enclose II in patients who underwent off-pump coronary artery bypass grafting (CABG).

METHODS

Enclose II was used for isolated off-pump CABG in 178 patients at six heart centers between October 2005 and December 2009. The preoperative characteristics of the patients, complications related to Enclose II, and early graft patency rates were examined.

RESULTS

A total of 222 proximal anastomoses were performed in 178 patients using Enclose II. Forty-four of these patients had two proximal anastomoses using this device. New cerebral infarction that arose in two patients (1.1%) was not related to Enclose II. No aortic injury occurred. The graft patency rate was 96.4% at 1 year after surgery.

CONCLUSIONS

Enclose II is a safe and useful assist device for proximal anastomoses in patients undergoing off-pump CABG.

Intraoperative epiaortic scanning for preventing early stroke after off-pump coronary artery bypass

BACKGROUND

Numerous studies have demonstrated the accuracy of epiaortic ultrasound scanning (EAS) for assessing ascending aortic disease. It remains unclear whether EAS changes the incidence of perioperative stroke after off-pump coronary artery bypass (OPCAB).

METHODS

We studied a retrospective cohort of 2292 patients who underwent isolated OPCAB from January 2001 to December 2011. Patients were retrospectively subdivided into two groups: the non-EAS group (n=1019) who underwent OPCAB under only intraoperative transoesophageal echocardiography and the EAS group (n=1273) who underwent OPCAB under EAS.

RESULTS

In the non-EAS group, 317 (31.1%) patients underwent OPCAB with partial aortic clamping and 702 (68.9%) underwent OPCAB without partial aorta clamping. In the EAS group, 301 (23.7%) patients underwent OPCAB with partial aortic clamping and 972 (76.3%) underwent OPCAB without partial aortic clamping. The incidence of early stroke was not different statistically between the EAS and non-EAS groups [non-EAS 1.7% (17/1019) vs EAS 0.8% (10/1273); P=0.052]. However, in the subgroups of patients with partial aorta clamping, the incidence of the early stroke was significantly lower in the EAS group [2.8% (9/317) vs 0.7% (2/301) P=0.041].

CONCLUSIONS

EAS has a significant clinical benefit in reducing the incidence of early stroke in cases of partial aortic clamping in OPCAB. Therefore, EAS should be considered in patients who need partial aortic clamping in OPCAB.

Extraanatomical coronary artery bypass grafting in patients with severely atherosclerotic (Porcelain) aorta

Background

Cannulation, cross clamping, or partial clamping of the aorta during a proximal anastomosis may cause embolic complications in patients with severely atherosclerotic (porcelain) aortas. These patients carry high morbidity and mortality risks due to intraoperative atheroembolism.

Methods

Between June 2008 and May 2010, 972 open heart surgery operations were performed in our department. In this group there were 41 patients who had severe atherosclerotic plaques in the aorta (porcelain aorta), and 9 of these underwent an extraanatomical coronary artery bypass grafting (CABG). These 9 patients were retrospectively analyzed and their demographic data, patient risk factors, and preferred surgical methods were reviewed.

Results

Seven patients underwent two-vessel CABG, while 2 underwent three-vessel CABG. Off-pump surgery was performed for 7 patients. CABG was performed with beating heart technique under cardiopulmonary bypass via femoral artery and right atrial cannulation without cross clamping in 2 of the patients. Postoperative course was uneventful in all patients. Mean length of stay in the intensive care unit was 2.11 ± 0.78 days. Mean hospitalization was 7.22 ± 0.97 days. Mean follow-up was 11.33 ± 3.67 months, and no cerebrovascular events were observed during this period. Postoperative evaluation of the grafts by multislice computed tomography revealed sufficient patency in all patients.

Conclusions

Innominate artery is an alternative inflow source for the untouchable ascending aorta caused by severe atherosclerotic disease (porcelain aorta). In this group of patients, the risk of systemic embolisation and perioperative neurologic complications can be minimized by avoiding manipulation of the ascending aorta and using the innominate artery.

Replacement of the ascending aorta for severe atherosclerosis during coronary artery bypass surgery

BACKGROUND AND AIM

In the present study, we investigated the benefit of ascending aorta replacement in patients with severe aortic atherosclerosis who undergo coronary artery bypass surgery (CABG).

METHODS

From January 2001 to April 2011, 3842 patients underwent CABG and in 36 of these patients (31 male, 5 female) the ascending aorta was replaced due to severe atherosclerosis. Total circulatory arrest was used in 22 patients (61%). The patients were followed for 69 ± 36 months (1-133 months) and compared to a control group of patients. The control group consisted of patients who underwent CABG with or without a concomitant procedure (n = 3806).

RESULTS

For the study group, the mean additive and logistic Euroscores of the patients were nine and 20, respectively. One stroke (2.8%) was observed and this patient died in the early postoperative period. There were a total of four confirmed deaths (12%) at any time point over the length of the follow-up among the patients who were discharged from the hospital. Two of them died of malignancy (lung and gastric tumors) and the other two from cardiac reasons. No patients had a stroke during follow-up. For the control group the mean age was 61 ± 1, the stroke rate was 0.6%, and the mortality rate was 0.96%, and the mean logistic and additive Euroscores were 3.7 ± 4.4, and 3.5 ± 2.5, respectively.

CONCLUSIONS

Replacement of highly calcified ascending aortas during CABG can be safely performed in selected patients with good long-term outcomes.

Combined aortic valve replacement and coronary artery bypass grafting for a calcified ascending aorta

Although a severely calcified ascending aorta is encountered infrequently, it presents formidable problems during cardiac surgery. We describe a case of severe aortic valve stenosis and coronary artery disease combined with a severely calcified ascending aorta. The patient was an 80-year-old man with a calcified ascending aorta. He successfully underwent an aortic valve replacement and a single coronary artery bypass graft (CABG) using a saphenous vein graft with the proximal end connected on a Dacron patch, which was used for aortoplasty of the calcified plate along the aortotomy. These procedures were performed under moderate hypothermia with aortic clamping. This patch aortoplasty can be a useful alternative in cases that require aortotomy and proximal anastomoses of a CABG on a calcified ascending aorta.

Improve morbidity and mortality in coronary artery bypass graft surgery for severe atherosclerosis

OBJECTIVES

Atherosclerosis has been identified as a risk factor for both morbidity and mortality in patients undergoing coronary artery bypass grafting (CABG). To investigate outcomes following CABG for severe atherosclerosis, and to determine whether different surgical techniques can reduce the risk of neurologic events in these patients.

METHODS

We studied 225 consecutive patients who underwent elective isolated CABG. Routine preoperative and intraoperative examinations identified patients with severe atherosclerosis. We compared the outcomes between patients with (group A; 42 ceses) and those without (group N; 183 cases) severe atherosclerosis.

RESULTS

36 patients (85.7%) in group A and 176 (96.2%) in group N underwent off-pump coronary artery bypass (OPCAB); 6 (14.3%) in group A and 7 (3.8%) in group N underwent on-pump beating CABG. Three patients in group A suffered deep sternal infection (7.1%), and one suffered stroke (2.4%) compared with none in group N. No cerebral infarction or neurologic events occurred in patients who underwent OPCAB (n = 212, 94.2%).

CONCLUSIONS

Prevalence of complications was significantly greater among patients with severe atherosclerotic disease who underwent OPCAB than in those without atherosclerotic disease. Careful selection of surgical strategies can prevent perioperative stroke and reduce mortality.

Postoperative cognitive dysfunction and aortic atheroma

BACKGROUND

The relationship of aortic atheroma to postoperative cognitive dysfunction (POCD), a common complication of coronary artery bypass graft surgery, has not been resolved. We undertook assessment of aortic atheroma using intraoperative ultrasonography and related the degree of aortic atheroma to POCD.

METHODS

Aortic atheroma was assessed using intraoperative transesophageal and epiaortic echocardiography in 311 patients who underwent coronary artery bypass graft surgery. Atheroma was graded from 0 (normal or minimal) to 3 (mobile or rough) in each of four quadrants of the proximal ascending to proximal descending thoracic aorta. Atheroma burden was defined as the atheroma score divided by the total possible score for that patient. Patients also completed a neuropsychological battery consisting of eight tests taken the week before surgery and at 1 week and 3 and 12 months afterward. Decreased cognitive function for each test was defined as an individual decrease of at least 1 standard deviation of the group baseline mean for that test, and POCD was defined as a decrease in two or more tests.

RESULTS

The atheroma burden (%) was greater in the patients with POCD. The difference was greatest at 1 week (10.4+/-14.7 versus 4.4+/-9.0, p=0.0002) and diminished progressively at 3 months (8.9+/-14.1 versus 5.4+/-10.1, p=0.06) and 12 months (6.6+/-12.0 versus 5.6+/-10.2, p=0.56). Multivariable analysis showed that atheroma burden strongly predicted POCD at 1 week.

CONCLUSIONS

Aortic atheroma burden predicts POCD at 1 week but has less impact on POCD as time progresses. Atheroma burden is highly correlated with age and may be a good predictor of early POCD.

Off-pump coronary artery revascularization in octogenarians: is it better?

PURPOSE OF REVIEW

Octogenarians are the fastest growing stratum of the population and have the highest prevalence of coronary artery disease. In the past, physicians have been reluctant to provide these patients with optimal care. Seniors are frequently excluded from large randomized trials and generally not included in published guidelines. The purpose of this review is to revisit the demography and epidemiology of coronary artery disease in this population as well as therapeutic strategies used.

RECENT FINDINGS

Recent publications have shown significant advancement in medical and invasive treatment of coronary artery disease in elderly, with special focus on the potential benefit of off-pump coronary artery bypass (OPCAB) surgery.

SUMMARY

Although OPCAB surgery has gained popularity over the past 15 years, its benefit regarding operative mortality and major complications has not been clearly defined in the general population. There is a body of literature supporting its benefit in the elderly population. OPCAB surgery has the potential of decreasing operative mortality and major postoperative complications such as stroke, delirium, atrial fibrillation, and decline in neurocognitive functions in these patients. Off-pump surgery is technically more demanding and has been blamed for providing less complete revascularization and lower graft patency rate, especially in less experienced hands. However, with the upcoming demographic explosion of senior citizens in western societies, OPCAB surgery has definitely to be a part of the armamentarium of modern cardiac surgeons.

“Beyond Beating Heart Surgery” Heartstring Device Protects against Perioperative Neurological Events

Objective

There is a growing body of evidence favoring off-pump coronary artery bypass surgery (OPCAB) over traditional coronary artery bypass surgery (CABG) with cardiopulmonary bypass as a method for reducing perioperative neurologic events. Aortic manipulation, whether with OPCAB or coronary artery bypass surgery with cardiopulmonary bypass, is strongly linked with adverse neurologic outcomes. Although the aortic “no-touch” technique has merit, most cardiac surgeons are reluctant to base entire myocardial revascularization exclusively on mammary pedicles. The purpose of this study was to analyze our experience with OPCAB combined with the use of a Heartstring proximal anastomotic device, as a strategy for reducing clinically evident cerebrovascular accidents.

Methods

Two hundred twenty-seven consecutive isolated OPCAB were performed without the use of a side-biting aortic clamp. In all these operations, a Heartstring device was used, permitting clampless hand-sutured proximal anastomoses. All patients were managed in this fashion regardless of the status of their ascending aorta. A mean of 3.4 bypasses were performed during each operation, with one or two mammary arteries harvested routinely. In 98% of patients, a single proximal anastomosis was performed; there was liberal use of sequential bypass grafts.

Results

Mean age was 69.3 years, with 17% octogenarians. Preexisting cerebrovascular disease was present in 22.4% of patients. There were no clinically evident perioperative neurologic events in any patients. There were no operative deaths.

Conclusions

This series suggests that OPCAB performed with a single, clampless, proximal aortic anastomosis, and with a Heartstring device may protect against perioperative strokes.

Current role and outcomes of ascending aortic replacement for severe nonaneurysmal aortic atherosclerosis

BACKGROUND

Severe atherosclerosis of the ascending aorta is a challenging issue potentially affecting indications for surgery, operative choices, and patients' outcome. No standard treatment has emerged to date, and uncertainties persist about criteria for selecting patients and procedures.

METHODS

Replacement of the atherosclerotic ascending aorta was performed in 64 patients at time of either aortic (n = 49), mitral (n = 21), or tricuspid (n = 7) valve surgery. Coronary artery bypass grafting was performed in 53 patients, and the majority of patients underwent combined procedures (n = 49). Mean age was 72.0 +/- 7.6 years. The expected operative mortality, by logistic European System for Cardiac Operative Risk Evaluation, was 29.0% accounting for ascending aortic replacement and 13.1% disregarding it. Circulatory arrest under deep hypothermia, eventually combined with either retrograde or antegrade brain perfusion, was required in 61 cases.

RESULTS

Early death, stroke, and myocardial infarction rates were 10.9%, 6.3%, and 7.8%, respectively. Factors univariately associated with early deaths were preoperative renal failure requiring dialysis (p = 0.001) and longer cardiopulmonary bypass (p = 0.001) and cardioplegia (p = 0.008) times. Cumulative survival at 1, 3, and 5 years was 86% +/- 4%, 74% +/- 6%, and 68% +/- 8%, respectively.

CONCLUSIONS

Replacement of the atherosclerotic ascending aorta can be carried out at acceptable mortality rates despite the high rates of preoperative comorbidity and the significant incidence of postoperative complications.

Neurologic complications in non-neurological intensive care units

BACKGROUND

Neurologists are frequently called to evaluate patients in the intensive care units who are not waking up. This often poses a diagnostic and prognostic dilemma.

REVIEW SUMMARY

The initial evaluation starts with abstracting the prehospital and in-hospital history, followed by bedside clinical and neurologic examination to establish a differential diagnosis. The subsequent work-up is based on clinical suspicion where reversible life-threatening causes should be immediately identified. After confirming the diagnosis and implementation of the appropriate medical management, a prompt family meeting and counseling is recommended. The role of neurologists in clinical diagnosis and prognostication of the coma patient, as well as diagnosing brain death is instrumental.

CONCLUSIONS

In this review, we explore a practical systematic approach to patients with decreased level of consciousness. The most common causes of impaired alertness in different non-neurologic critical care units and commonly used prognostication tools are presented. Finally a brief introduction of hypothermia, a novel therapeutic approach is also discussed.

Preoperative evaluation and preparation of the patient for cardiac surgery

Cardiac surgery is associated with significant morbidity, mortality, and socioeconomic costs. Preoperative assessment assists the clinician in identifying potential complications and facilitates discussion of these risks with the patient. Careful patient selection and preparation during preoperative evaluation may minimize morbidity, mortality, and resource use. This article outlines a system-based approach to preoperative evaluation and preparation of the patient undergoing cardiac surgery.

Preoperative screening and management of carotid artery disease in patients undergoing cardiac surgery

BACKGROUND

Carotid artery stenosis (CAS) is a well-known risk factor for perioperative stroke in cardiac surgery. It is unclear whether preoperative carotid screening should be applied to all patients. Carotid intervention concomitantly with cardiac operations is also controversial. Our objective was to identify the prevalence of significant CAS and its related risk factors by applying a protocol of preoperative carotid screening to all patients undergoing cardiac surgery.

METHODS

We studied 307 patients who were primarily screened preoperatively by duplex Doppler ultrasonography. Catheter carotid angiography or transcranial Doppler was performed on equivocal cases. Univariate and multivariate analyses were applied across selected parameters to identify risk factors for significant CAS (> 70%). The prevalence of CAS and perioperative stroke rates were determined.

RESULTS

Twenty-two patients with severe and 18 with moderate carotid stenosis were identified. Further radiological evaluation with catheter carotid angiography and transcranial Doppler confirmed the presence of significant CAS in 20 patients who underwent carotid stenting or endarterectomy before the open heart surgery. The cardiac surgeon was free to modify the surgical technique according to the preoperative assessment. No patient had major stroke perioperatively, while two minor strokes with complete neurologic recovery have been documented. The history of stroke and the presence of bruit on clinical examination were the only significant predictors of severe carotid disease.

CONCLUSION

Careful clinical examination together with detailed previous history taking can identify the majority of patients with CAS. Further data are required for the construction of a scientifically valid policy as a guideline.

Preoperative evaluation and preparation of the patient for cardiac surgery

Cardiac surgery is associated with significant morbidity, mortality, and socioeconomic costs. Preoperative assessment assists the clinician in identifying potential complications and facilitates discussion of these risks with the patient. Careful patient selection and preparation during preoperative evaluation may minimize morbidity, mortality, and resource use. This article outlines a system-based approach to preoperative evaluation and preparation of the patient undergoing cardiac surgery.

Meta-analysis of the diagnostic accuracy of transesophageal echocardiography for assessment of atherosclerosis in the ascending aorta in patients undergoing cardiac surgery

BACKGROUND

Stroke after cardiac surgery may be caused by emboli emerging from an atherosclerotic ascending aorta (AA). Epiaortic ultrasound scanning (EUS), the current 'gold' standard for detecting AA atherosclerosis, has not gained widespread use because there is a lack of optimized ultrasound devices, it lengthens the procedure, it endangers sterility, and there is a false belief by many surgeons that palpation is as sensitive as EUS. Furthermore there is no clear evidence proving that the use of epiaortic scanning changes outcome in cardiac surgery. Various researchers investigated the ability of transesophageal echocardiography (TEE) to discriminate between the presence and absence of AA atherosclerosis. It is acknowledged that TEE has limited value in this, but it has never been supported by a meta-analysis estimating the true diagnostic accuracy of TEE based on all quantitative evidence. We aimed to do this using state-of-the-art methodology of diagnostic meta-analyses.

METHODS

We searched multiple databases for studies comparing TEE vs. EUS for detection of atherosclerosis. A random-effects bivariate meta-regression model was used to obtain summary estimates of sensitivity and specificity, incorporating the correlation between sensitivity and specificity as well as covariates to explore heterogeneity across studies.

RESULTS

We extracted six studies with a total of 346 patients, of whom 419 aortic segments were analyzed, including 100 segments with atherosclerosis [median prevalence 25% (range 17-62%)]. Summary estimates of sensitivity and specificity were 21% (95% CI 13-32%) and 99% (96-99%), respectively.

CONCLUSIONS

Because of the low sensitivity of TEE for the detection of AA atherosclerosis, a negative test result requires verification by additional testing using epiaortic scanning. In case of a positive test result, AA atherosclerosis can be considered as present, and less manipulative strategies might be indicated.

Epiaortic scanning modifies planned intraoperative surgical management but not cerebral embolic load during coronary artery bypass surgery

BACKGROUND

Patients with aortic atheroma are at increased risk for neurological injury after coronary artery bypass graft (CABG) surgery. We sought to determine the role of epiaortic ultrasound scanning for reducing cerebral embolic load, and whether its use leads to changes of planned intraoperative surgical management in patients undergoing CABG surgery.

METHODS

Patients >70-yr-of-age scheduled for CABG surgery were prospectively randomized to either an epiaortic scanning (EAS) group (aortic manipulation guided by epiaortic ultrasound) or a control group (manual aortic palpation without EAS). All patients received a comprehensive transesophageal echocardiographic examination. Transcranial Doppler (TCD) was used to monitor the middle cerebral arteries for emboli continuously from 2 min before aortic cannulation to 2 min after aortic decannulation. Neurological assessment was performed with the National Institute of Health stroke scale before surgery and at hospital discharge. The NEECHAM confusion scale was used for assessment and monitoring of patient global cognitive function on each day after surgery until hospital discharge.

RESULTS

Intraoperative surgical management was changed in 16 of 55 (29%) patients in the EAS group and in 7 of 58 (12%) patients in the control group (P = 0.025). These changes included adjustments of the ascending aorta cannulation site for cardiopulmonary bypass (CPB), the avoidance of aortic cross-clamping by using ventricular fibrillatory arrest during surgery, or by conversion to off-pump surgery. During surgery, 7 of 58 (12%) patients in the control group crossed over to the EAS group based on the results of manual aortic palpation. The median [range] TCD detected cerebral embolic count did not differ between the EAS and control groups during aortic manipulations (EAS, 11.5 [1-516] vs control, 22.0 [1-160], P = 0.91) or during CPB (EAS, 42.0 [4-516] vs control, 63.0 [5-758], P = 0.46). The NEECHAM confusion scores and National Institute of Health stroke scale scores were similar between the two groups.

CONCLUSIONS

These results show that the use of EAS led to modifications in intraoperative surgical management in almost one-third of patients undergoing CABG surgery. The use of EAS did not lead to a reduced number of TCD-detected cerebral emboli before or during CPB.

Cardiac anesthesia and surgery in geriatric patients

The average age of US population is steadily increasing, with more than 15 million people aged 80 and older. Coronary artery disease and degenerative cardiovascular diseases are particularly prevalent in this population. Consequently, an increasing number of elderly patients are referred for surgical intervention. Advanced age is associated with decreased physiologic reserve and significant comorbidity. Thorough preoperative assessment, identification of the risk factors for perioperative morbidity and mortality, and optimal preparation are critical in these patients. Age-related changes in comorbidities and altered pharmacokinetics and pharmacodynamics impacts anesthetic management, perioperative monitoring, postoperative care, and outcome. This article updates the age-related changes in organ subsystems relevant to cardiac anesthesia, perioperative issues, and intraoperative management. Early and late operative outcome in octogenarians undergoing cardiac surgery are reviewed. The data clearly indicate that no patient group is "too old" for cardiac surgery and that excellent outcomes can be achieved in selected group of elderly patients.

Excellent Results of Contemporary Coronary Artery Bypass Grafting with Systematic Application of Modern Perioperative Strategies

BACKGROUND

The patient population referred for coronary artery bypass grafting (CABG) has become more challenging. The surgical population is aging and patients present with significant preoperative comorbidities. This worsening risk profile has led to the development of operative techniques (off-pump CABG) and perioperative measures (epi-aortic scanning, intensive insulin therapy) to preserve the quality of care following CABG. The aim of this study was to determine the outcome of contemporary CABG following the implementation of the above measures in our practice.

METHODS

We retrospectively analyzed prospectively collected data of 2725 patients undergoing CABG between 01/1998 and 12/2005 (mean age, 65 +/- 11 years; 843 [31%] female; mean ejection fraction, 45% +/- 14%). Outcome measures included hospital mortality, postoperative complications, and long-term survival and independent predictors of outcome. Subgroup analyses were performed for 2 study periods (1998-2002 versus 2003-2005) where the above measures were implemented and for patients undergoing conventional versus off-pump CABG.

RESULTS

When comparing the 2 study periods, we observed a substantial worsening of the risk profile with an increased EuroSCORE predicted mortality from 6.4% +/- 6.8% to 7.0% +/- 7.8% (P = .028). During the same period, operative mortality decreased from 2.4% to 0.7% (P < .001). This reduction in mortality was also observed in diabetic patients (3.1% versus 1.0%, P = .021) and those with low ejection fraction (4% versus 2.6%, P = not significant). Off-pump procedures were performed with an increasing frequency in high-risk patients in whom we obtained excellent results. Finally, we observed a reduction of postoperative complications including respiratory failure (P = .013), gastrointestinal complications (P = .017), and stroke (P = .094). Independent predictors of mortality included renal failure (OR = 5.7), peripheral vascular disease (OR = 2.9), intra-aortic balloon pump (OR = 4.8), reoperation (OR = 3.3), and hypertension (OR = 2.3).

CONCLUSION

Despite a worsening case mix, contemporary CABG can be performed with excellent results (operative mortality < 1%). Off-pump CABG performed in very high-risk patients obtains results similar to those of the general CABG population. Diabetes and ejection fraction were not independent predictors of early outcome. In our experience, these excellent outcomes were achieved by adopting an operative approach using modern perioperative management (epi-aortic scanning, intensive insulin therapy) and surgical techniques (off-pump CABG) based on individual patients.

Predictors and outcome of gastrointestinal complications in patients undergoing cardiac surgery

OBJECTIVE

To determine the incidence and independent predictors of gastrointestinal complications (GICs) following cardiac surgery.

SUMMARY BACKGROUND DATA

Gastrointestinal ischemia and hemorrhage represent a rare but devastating complication following heart surgery. The profile of patients referred for cardiac surgery has changed during the last decade, questioning the validity of previously reported incidence and risk factors.

METHODS

We retrospectively analyzed prospectively collected data from 4819 patients undergoing cardiac surgery between 1998 and 2004. Patients with GICs were compared with the entire patient population. Study endpoints were mortality, postoperative morbidities, and long-term survival.

RESULTS

GICs occurred in 51 (1.1%) patients. Etiologies were intestinal ischemia (n = 30; 59%) and hemorrhage (n = 21; 41%). The incidence decreased during the study period (1998-2001: 1.3%, 2002-2004: 0.7%; P = 0.04). The incidence per type of procedure was as follows: coronary artery bypass grafting (CABG)/valve (2.4%), aortic surgery (1.7%), valve surgery (1.0%), and CABG (0.5%; P = 0.001). Multivariate analysis revealed age (odds ratio [OR] = 2.1), myocardial infarction (OR = 2.5), CHF (OR = 2.4), hemodynamic instability (OR = 2.8), cardiopulmonary bypass time >120 minutes (OR = 6.2), peripheral vascular disease (OR = 2.2), renal (OR = 3.2), and hepatic failure (OR = 10.8) as independent predictors of GICs. The overall hospital mortality among patients with GICs was 33%. Long-term survival was significantly decreased in patients with GICs compared with the control group.

CONCLUSIONS

Gastrointestinal complications following cardiac surgery remain rare with an incidence <1% in a contemporary series. The key to a lower incidence of GICs lies in systematic application of preventive measures and new advances in intraoperative management. Identification of independent risk factors would facilitate the determination of patients who would benefit from additional perioperative monitoring. Future resources should therefore be redirected to mitigate GICs in high-risk patients.

[Neurological complications in cardiac surgery post-operative period]

The incidence of neurological complications after cardiac surgery continues to be elevated, although this is variable in the different studies published, fundamentally because of the different populations studied and the different definitions of neurological dysfunction. The etiology of these alterations is attributed to a multifactorial origin, aortic artherosclerosis, cerebral hypoperfusion and inflammatory phenomenon secondary to the technique. This review arises from the recognition of the personal, economic, and socio-health care repercussion entailed by these complications, with high rates of mortality and morbidity recorded, and it tries to give an objective view of the current literature on the subject. Having knowledge of the risk markers and understanding the pathogenesis is important to try to plan strategies that may minimize the appearance and development of these complications and contribute to the decrease of their serious consequences. The data and the experience obtained by our group are shown at the end of the review.

Screening Carotid Sonography Before Elective Coronary Artery Bypass Graft Surgery: Who Needs It

OBJECTIVE

The purpose of this study was to determine whether selection criteria for performing carotid sonographic screening before elective coronary artery bypass graft surgery can decrease the number of negative examinations without overlooking patients with significant carotid disease.

SUBJECTS AND METHODS

A history of peripheral vascular disease, a prior cerebrovascular event, smoking, diabetes, hypertension, cervical carotid disease, left main coronary disease, and patient sex were criteria prospectively gathered for 295 consecutive patients undergoing screening carotid sonography before elective coronary artery bypass surgery. Logistic regression modeling was used to determine if any single criterion or combination of criteria could be applied to decrease the number of screening examinations without sacrificing detection of significant (> or = 50% cross-sectional narrowing) carotid stenosis.

RESULTS

Smoking, diabetes, hypertension, a previous cerebrovascular event, peripheral vascular disease, left main coronary artery disease, and a history of cervical carotid disease were associated with significant carotid disease (chi-square test) in our subject population. Logistic modeling showed that the probability of detecting significant carotid disease increases 2.98 times for each additional selection criterion present. Possessing at least one selection criterion would still yield 100% examination sensitivity while increasing specificity to 30.0%.

CONCLUSION

Selection criteria should be applied when choosing patients for carotid sonographic screening before elective coronary artery bypass surgery. This approach would decrease the number of noncontributory examinations but would have little effect on the detection of significant carotid stenosis in this target population.

Improved neurologic outcome after implementing evidence-based guidelines for cardiac surgery

OBJECTIVE

A high incidence of neurologic complications was observed in the year 2001 in cardiac surgical patients in this department. This article attempts to show the impact of changing and optimizing management protocols on the incidence of neurologic morbidity after cardiac surgery.

DESIGN

An observational study of cardiac surgical patients.

SETTING

University hospital.

PARTICIPANTS

All cardiac surgical patients treated postoperatively in the cardiac surgical ICU in 2001 (n = 1,165, control group) and in 2003 (n = 1,222, intervention group) were evaluated.

INTERVENTIONS

A quality improvement program started at the beginning of 2002, based on the Task Force Committee Guidelines, included surgical and cardiopulmonary bypass recommendations as well as peri- and postoperative care (eg, use of epiaortic echo and strict perfusion protocol, avoidance of hyperthermia and hyperglycemia, and minimization of cerebral edema).

RESULTS

The number of neurologic complications decreased from 78 (6.7%) in 2001 to 33 (2.7%) in 2003 (p < 0.01), and corresponding numbers for ICU mortality were 44 (3.8%) and 24 (2.0%) (p < 0.01). The length of ICU stay also decreased (3.2 +/- 4.5 days in 2001 v 2.9 +/- 5.5 days in 2003, p < 0.001). In 2001, patients with neurologic complications consumed 853 ICU patient days (23% of all ICU patient days) and, in 2003, 549 (15% of all ICU patient days). According to logistic regression analysis that included 11 independent variables (treatment year, EuroSCORE, diabetes mellitus, history of stroke, and 7 different types of surgery), treatment in 2003 was independently associated with decreased risk for neurologic complications (odds ratio 0.30, 95% confidence intervals 0.19-0.47, p < 0.001).

CONCLUSIONS

The occurrences of neurologic complications, mortality, and ICU resource consumption by this patient group decreased after implementation of an optimized management protocol and evidence-based guidelines.

Resolving the blind spot of transoesophageal echocardiography: a new diagnostic device for visualizing the ascending aorta in cardiac surgery

BACKGROUND

Atherosclerosis of the ascending aorta (AA) and stroke after cardiac surgery are related. Knowledge of the location of AA-atherosclerosis pre-sternotomy allows changes in surgical strategy to avoid manipulation of the AA. The gold-standard for assessment of AA-atherosclerosis is intraoperative epiaortic ultrasound scanning (EUS). Transoesophageal echocardiography (TOE) is unable to detect atherosclerosis in the distal AA due to the 'blind spot'. A new method [A-View (Aortic-view) method] using a fluid-filled catheter may enhance the assessment of distal AA-atherosclerosis. The aim of this study was to evaluate whether the A-View method indeed visualizes the distal AA and to assess the safety of this technology.

METHODS

In a cross-sectional diagnostic study, 41 patients undergoing cardiac surgery including sternotomy underwent the same work-up including TOE, the A-View method, EUS, and routine operative monitoring.

RESULTS

With the A-View method, the distal AA was visible in all (100%) patients. There were no clinical important side-effects associated with the use of the A-View catheter; however, in one patient the endotracheal tube was accidentally dislocated leading to a decrease in Sa(O2). Severity of atherosclerosis visualized with the A-View method compared with EUS results showed good agreement between the two methods [Kappa of 0.69 (0.50-0.88)]. The Bland-Altman analysis showed poor agreement in plaque-size measurements (bias 0.05 cm2, limits of agreement - 0.63 to 0.74 cm2).

CONCLUSIONS

The A-View method offers a minimally invasive and safe approach to preoperatively resolving the blind spot of TOE. Compared with EUS, the A-View method yielded satisfactory results in the detection of AA-atherosclerosis. The A-View method seems a promising tool for patients undergoing cardiac surgery to direct surgical management.

Early results of a comprehensive operative and perfusion strategy to attenuate the incidence of adverse neurological outcomes in on-pump coronary artery bypass grafting (CABG) patients

Adverse neurological events, both focal (Type I) and non-focal (Type II), have been appreciated in postoperative on-pump coronary artery bypass grafting (CABG) patients for many years. Advanced age is a significant risk factor for adverse neurological events following CABG surgery. With full knowledge that our elderly population of patients was at high risk for these untoward neurological events, we adopted a comprehensive operative and perfusion strategy in an attempt to attenuate the incidence of these complications. Our strategy included efforts to minimise the number of emboli generated during the operation, avoid cerebral hypoperfusion, and attenuate the systemic inflammatory response. From 15 August 2002 to 31 December 2005, we performed 355 on-pump CABG operations. The incidence of Type I focal injury was 0/355 (0%), the incidence of Type II non-focal injury was 9/355 (2.5%), and postoperative mortality was 2/355 (0.6%). These results compared favorably to the results predicted by the Society of Thoracic Surgeons' (STS) model, and may suggest efficacy.

Surgical management of the atherosclerotic ascending aorta: is endoaortic balloon occlusion safe?

BACKGROUND

Occlusion of the atherosclerotic ascending aorta by an endoaortic inflatable balloon has been proposed as an alternative to conventional cross-clamping to prevent injury to the vessel and distal embolization of debris. The safety and the effectiveness of endoaortic occlusion have not been documented in this setting.

METHODS

Endoaortic occlusion was employed in 52 of 2,172 consecutive patients. Surgeon's choice was based on preoperative identification of aortic calcifications or intraoperative epiaortic ultrasonographic scanning. Deaths and strokes were analyzed casewise and in aggregate.

RESULTS

In 10 patients (19.2%), the endoaortic balloon had to be replaced by the ordinary cross-clamp because of incomplete occlusion (n = 5), hindered exposure (n = 2), or balloon rupture (n = 3). In-hospital death occurred in 13 patients (25%), and stroke on awakening from anesthesia in 2 (3.8%). The death rate of patients treated by endoaortic occlusion was significantly higher compared with all other patients (4.2%, p < 0.0001) and with the expected estimate by European System for Cardiac Operative Risk Evaluation (10.5%, p = 0.05). By multivariable analysis, use of endoaortic occlusion was independently associated with in-hospital death (odds ratio = 5.609, 95% confidence interval: 2.684 to 11.719). Although the stroke rate was higher in the endoaortic occlusion group compared with all other patients, the difference was only possibly significant (3.8% versus 0.8%, p = 0.067).

CONCLUSIONS

In this series, the endoaortic occlusion was frequently ineffective, and was associated with a significantly higher risk of in-hospital death and a numerically higher risk of stroke.

Central nervous system injury associated with cardiac surgery

Millions of individuals with coronary artery or valvular heart disease have been given a new chance at life by heart surgery, but the potential for neurological injury is an Achilles heel. Technological advancements and innovations in surgical and anaesthetic technique have allowed us to offer surgical treatment to patients at the extremes of age and infirmity-the group at greatest risk for neurological injury. Neurocognitive dysfunction is a complication of cardiac surgery that can restrict the improved quality of life that patients usually experience after heart surgery. With a broader understanding of the frequency and effects of neurological injury from cardiac surgery and its implications for patients in both the short term and the long term, we should be able to give personalised treatments and thus preserve both their quantity and quality of life. We describe these issues and the controversies that merit continued investigation.

Propensity Case-Matched Analysis of Off-Pump Versus On-Pump Coronary Artery Bypass Grafting in Patients With Atheromatous Aorta

BACKGROUND

Patients with severe atheromatous disease of the aorta who underwent coronary artery bypass grafting have an increased risk of stroke and death. We hypothesize that in these high-risk patients off-pump coronary artery bypass grafting is associated with lower rates of stroke and mortality.

METHODS

From January 1995 through June 2004, a total of 24,107 patients underwent coronary artery bypass grafting. Routine intraoperative transesophageal echocardiography was performed in 18,501, of which 6,991 (29.0%) were found to have severe atheromatous disease in the ascending aorta or aortic arch. Propensity matched-pairs analysis was used to match patients undergoing off-pump coronary artery bypass grafting (n = 3,000) with 3,000 patients undergoing conventional coronary artery bypass grafting by age, sex, ejection fraction, diabetes, preoperative intraaortic balloon pump, congestive heart failure, chronic obstructive pulmonary disease, acute myocardial infarction, peripheral vascular disease, history of stroke or cerebrovascular disease, renal disease, carotid artery disease, atrial fibrillation, emergency surgery, or previous cardiac surgery.

RESULTS

Univariate analysis revealed decreased hospital mortality (1.4% versus 3.3%; p < 0.001) and stroke prevalence (0.50% versus 0.97%; p = 0.05) in off-pump coronary artery bypass grafting compared with conventional coronary artery bypass grafting. Multivariate analysis revealed that increased mortality was associated with conventional coronary artery bypass grafting (odds ratio, 2.6; p = 0.001), age (odds ratio, 2.1; p = 0.003), acute myocardial infarction (odds ratio, 1.8; p = 0.03), history of stroke or cerebrovascular disease (odds ratio, 1.6; p = 0.04), congestive heart failure (odds ratio, 2.1; p = 0.04), and diabetes mellitus (odds ratio, 1.9; p = 0.03). Multivariate analysis showed that off-pump coronary artery bypass grafting technique was the only independent predictor of decreased stroke rate (odds ratio, 1.4; p = 0.05).

CONCLUSIONS

Off-pump coronary artery bypass grafting surgery in patients with atheromatous disease of the aorta is associated with lower risk of stroke and death. Routine intraoperative evaluation of the aorta is helpful in identifying the disease and directs the appropriate surgical technique.