Atherosclerosis of the ascending aorta. Prevalence and role as an independent predictor of cerebrovascular events in cardiac patients

Assessment of silent brain injury in patients undergoing elective percutaneous coronary intervention due to chronic total occlusion

Objective: Silent brain infarcts (SBI) are thromboembolic complications associated with cardiac surgery, diagnostic angiography, and percutaneous interventions. Serum neuron-specific enolase (NSE) is the proven biomarker for measuring neuronal damage. This study aimed to evaluate the incidence of SBI, defined as elevated NSE after coronary chronic total occlusion (CTO) intervention and elective coronary stenting. Design: The study population consisted of two patient groups: the CTO group included consecutive patients with coronary CTO intervention, and the control group consisted of patients who underwent elective coronary intervention. NSE blood levels were measured before and 12-18 h after the procedure. NSE blood levels of >20 ng/mL were considered SBI. Results: A total of 108 patients were included in the study. Of these, 55 (50.9%) had SBI after the procedure. The SBI rate was 59.7% in the CTO group and 39.1% in the control group. Patients with SBI were more likely to have diabetes mellitus, hyperlipidemia, higher HbA1c, higher total stent length, and longer procedural time. Multivariate logistic regression analysis showed that CTO procedure (odds ratio [OR]: 3.129; 95% confidence interval [CI]: 1.246-7.858; p < 0.015) and diabetes mellitus (OR: 2.93; 95% CI: 1.185-7.291; p < 0.020) are independent predictors of SBI. Conclusion: Our data suggest that SBI occurs more frequently after CTO intervention than after non-CTO intervention. Intervention complexity and patient clinical characteristics may explain the increased incidence.

The brain-before-heart strategy for coronary artery bypass grafting in the severely atherosclerotic aorta: A single-institution experience

BACKGROUND

Severe atherosclerosis of the ascending aorta (SAA) in patients undergoing surgical revascularization by coronary artery bypass grafting (CABG) is becoming an increasing problem as more elderly patients are diagnosed with coronary artery disease. Strokes and other neurologic insults are common complications in this group, with devastating impacts on outcomes and prognoses.

HYPOTHESIS

Early detection of the atherosclerotic aorta and the application of a stroke prevention protocol will reduce the risk of stroke in patients with SAA.

METHODS

In 2012, we adopted a protocol devised to preemptively detect and manage patients suspected of having SAA. From the time of the application of the protocol, we compared the immediate and late outcomes of CABG in SAA in the 8 years preceding the protocol in a "control" group (30 patients) and in the 8 years following the protocol in a "brain" group (69 patients).

RESULTS

More patients with SAA were detected after the initiation of the protocol. They had significantly more history of stroke, renal dysfunction, and left main coronary disease. The percutaneous coronary intervention was utilized more after the protocol (26% vs. 7%) and there was far less utilization of replacement of the ascending aorta (12% vs. 37%). Postoperative stroke rates were significantly less after the protocol (2% vs. 18%), with an almost twofold reduction in stroke associated with SAA even after risk adjustment. The composite endpoints of cardiac death, nonfatal myocardial infarction, and stroke were significantly reduced after initiating the protocol at a median of 2.3 years from the time of revascularization.

CONCLUSION

Early detection of SAA and individualized therapeutic strategies for revascularization is effective in reducing athero-embolic brain injury and are associated with better prognosis.

A Cerebrovascular Incident Secondary to Extensive Aortic Arch Atheroma

Plaques can form across different parts of the aorta, from the aortic arch to the thoracic and abdominal aorta. Aortic arch atheroma, however, is highly associated with cerebrovascular insults due to their dislodgement. Although no concise management protocol has been defined for dealing with such presentations, antiplatelet agents and anticoagulants are most frequently used. In this case, we present a 78-year-old male with a known case of diabetes mellitus type 2, hypertension, and dyslipidemia who presented to the emergency department with acute onset of slurred speech. A CT angiography was performed that revealed extensive plaque formations across the aortic arch with a 90% occlusion of the distal left common carotid artery and carotid bifurcation along with 99% stenosis of the internal carotid artery. The patient underwent aspiration thrombectomy and was started on dual antiplatelets but passed away after developing decompensated heart failure.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

Sleep duration and vascular inflammation using hybrid positron emission tomography/magnetic resonance imaging: results from the Multi-Ethnic Study of Atherosclerosis (MESA)

STUDY OBJECTIVES

Short sleep duration (SD) is associated with cardiovascular disease (CVD). We investigated the relationship between objective SD and subclinical atherosclerosis employing hybrid PET/MRI with ¹⁸F-FDG tracer in the MESA cohort.

METHODS

We utilized data from MESA-SLEEP and MESA-PET ancillary studies. SD and sleep fragmentation index (SFI) were assessed using 7-day actigraphy. The primary and secondary outcomes were carotid inflammation, defined using target-to-background ratios (TBR), and measures of carotid wall remodeling (carotid wall thickness [CWT]), summarized by SD category. Multivariate linear regression was performed to assess the association between SD and SFI with the primary/secondary outcomes, adjusting for several covariates including apnea-hypopnea index (AHI), and CVD risk.

RESULTS

Our analytical sample (n=58) was 62% female (mean age 68±8.4 years). Average SD was 5.1±0.9 hours in the short SD group (≤6 hours/night, 31%), and 7.1±0.8 hours in the normal SD group (69%). Prevalence of pathologic vascular inflammation (TBRmax>1.6) was higher in the short SD group (89% vs. 53%, p=0.009). Those with short SD had a higher TBRmax (1.77 vs 1.71), though this was not statistically significant (p=0.39). CWT was positively correlated with SFI even after adjusting for covariates (Beta [SE]=0.073±[0.032], p=0.025).

CONCLUSIONS

Prevalence of pathologic vascular inflammation was higher among those who slept ≤6 hours, and vascular inflammation was higher among those with a SD of ≤6 hours. Interestingly, SFI was positively correlated with CWT even after adjustment for covariates. Our results are hypothesis-generating but suggest that both habitual SD and SFI should be investigated in future studies as potential risk factors for subclinical atherosclerosis.

Aortic Sources of Embolism

Aortic arch atheroma is a frequent finding in ischemic stroke patients. Its role as a source of cerebral emboli or a marker of atherosclerosis is unclear. Transesophageal echography is considered the gold standard for its detection, whereas computed tomography angiography is a good alternative; magnetic resonance and positron emission tomography could be proposed to better analyze plaque vulnerability. Despite the interest in this condition, the optimal antithrombotic treatment remains uncertain, while intensive lipid-lowering therapy should be recommended. This review aims to offer guidance on patients with aortic arch atheroma, about its causal role in stroke, diagnosis, and treatment based on current available evidence.

Coronary artery bypass grafting and perioperative stroke: imaging of atherosclerotic plaques in the ascending aorta with ungated high-pitch CT-angiography

Perioperative stroke is a devastating complication after coronary artery bypass graft (CABG) surgery, with atherosclerosis of the ascending aorta as important risk factor. During surgical manipulation, detachment of plaques can lead to consecutive embolization into brain-supplying arteries. High-pitch computed tomography angiography (HP-CTA) represents a non-invasive imaging modality, which provides the opportunity for comprehensive imaging of the ascending aorta, including plaque detection and advanced characterization. In our present retrospective study on 719 individuals, who had undergone HP-CTA within 6 months prior to CABG, atherosclerotic disease of the ascending aorta was evaluated with respect to perioperative stroke rates. For image analysis, the ascending aorta was divided into a proximal and distal part, consisting of four segments, and evaluated for presence and distribution of calcified and mixed plaques. All patients with perioperative stroke presented with atherosclerotic disease of the ascending aorta. The stroke rate was significantly associated with the presence and extent of atherosclerotic disease. Patients burdened with mixed plaques presented with significantly higher perioperative stroke rates. This study demonstrates that HP-CTA allows accurate evaluation of plaque extent and composition in the ascending aorta, and therefore may improve risk stratification of stroke prior to CABG.

Complexity of Aortic Arch Anatomy Affects the Outcomes of Transcarotid Artery Revascularization Versus Transfemoral Carotid Artery Stenting

BACKGROUND

Transcarotid artery revascularization (TCAR) has been shown to have half the rates of transient ischemic attack (TIA), stroke, and death compared with transfemoral carotid artery stenting (TFCAS). Successful outcomes of TFCAS require careful patient selection. The aim of this study was to determine the outcomes of TFCAS versus TCAR in both simple (type I) and complex (type II and III) aortic arches.

METHODS

A retrospective cohort study was performed comparing the outcomes of patients undergoing TFCAS versus TCAR with simple and complex aortic arches using the Vascular Quality Initiative registry from August 2011 to May 2019. The primary outcome was a composite of in-hospital TIA/stroke/death.

RESULTS

About 6,108 carotid artery interventions were analyzed, including 3,536 (57.9%) patients with type I, 2,013 (33.0%) with type II, and 559 (9.2%) with type III aortic arch. In 3,535 patients with a simple arch, 1,917 underwent TFCAS and 1,619 had TCAR. Mean age was 70.6 (±9.5) years, and 2,382 (67.4%) patients were males. The primary outcome of postoperative TIA/stroke/death was seen significantly less frequently in those undergoing TCAR compared with TFCAS in simple arches (odds ratio [OR], 0.63; 95% confidence interval [95% CI], 0.43-0.94; P = 0.0236). Although the individual outcome of death occurred less often in TCAR (P = 0.0025), there was no difference in the occurrence of in-hospital stroke (P = 0.8836) or TIA (P = 0.4608). On multivariable analysis, TCAR was associated with improved outcomes (P = 0.0062). A worse outcome was associated with increasing age (P < 0.001), a prior stroke (P < 0.0001), and increasing number of stents (P = 0.0483). In 2,572 patients with a complex arch, 1,416 underwent TFCAS and 1,156 had TCAR. Mean age was 73.0 (±9.1) years, and 1,655 (64.4%) were males. In complex arch anatomy, the primary outcome of in-hospital TIA/stroke/death was seen significantly less frequently in TCAR compared with TFCAS (OR, 0.49; 95% CI, 0.31-0.77; P = 0.0022). Again noted was a significant difference in death, with better outcomes in TCAR (P = 0.0133). Although the occurrence of in-hospital TIA was no different between the 2 approaches (P = 0.6158), there were significantly fewer strokes in those treated with TCAR (P = 0.0132). TCAR (P = 0.0146) was associated with improved outcomes. A worse outcome was seen with advancing age (P = 0.0003), prior strokes (P = 0.01), and a left-sided lesion (P = 0.0176).

CONCLUSIONS

TCAR has improved outcomes of TIA/stroke/death compared with TFCAS in both simple and complex aortic arch anatomy. In simple aortic arches, there is no difference in neurologic outcomes between both approaches. In complex arch anatomy, TCAR has fewer strokes.

Epiaortic Ultrasound for Assessment of Intraluminal Atheroma; Insights from the REGROUP Trial

OBJECTIVES

To assess the use of epiaortic ultrasound in contemporary cardiac surgery, as well as its impact on surgical cannulation strategy and cerebrovascular events.

DESIGN

Epiaortic ultrasound data was prospectively collected in the Randomized Endovein Graft Prospective (REGROUP) trial (VA Cooperative Studies Program #588, ClinicalTrials.gov, NCT01850082), which randomized 1,150 coronary artery bypass graft patients between 2014 and 2017 to endoscopic or open-vein graft harvest.

SETTING

Sixteen cardiac surgery programs within the Veterans Affairs Healthcare System with expertise at performing endoscopic vein-graft harvesting.

PARTICIPANTS

Veterans Affairs patients, greater than 18 years of age, undergoing elective or urgent coronary artery bypass grafting with cardiopulmonary bypass and cardioplegic arrest with at least one planned saphenous vein graft were eligible for enrollment.

INTERVENTIONS

Epiaortic ultrasound was performed by the surgeon using a high frequency (>7 MHz) ultrasound transducer. Two-dimensional images of the ascending aorta in multiple planes were acquired before aortic cannulation and cross-clamping.

MEASUREMENTS AND MAIN RESULTS

Epiaortic ultrasound was performed in 34.1% (269 of 790) of patients in REGROUP. Among these patients, simple intraluminal atheroma was observed in 21.9% (59 269), and complex intraluminal atheroma comprised 2.2% (6 of 269). The aortic cannulation or cross-clamp strategy was modified based on these findings in 7.1% of cases (19 of 269). There was no difference in stroke between patients who underwent epiaortic ultrasound and those who did not (1.9% v 1.2% p = 0.523).

CONCLUSIONS

Despite current guidelines recommending routine use of epiaortic ultrasound (IIa/B) to reduce the risk of stroke in cardiac surgery, in this contemporary trial, use remains infrequent, with significant site-to-site variability.

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.

Thoracic aortic calcium, cardiovascular disease events, and all-cause mortality in asymptomatic individuals with zero coronary calcium: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

TAC is associated with incident CVD and all-cause mortality. Nevertheless, the independent 10-year prognostic value of TAC in individuals with CAC = 0 beyond traditional risk factors is not well established.

METHODS

3415 MESA participants with baseline CAC = 0 were followed for CHD, CVD events and all-cause mortality. TAC was measured in the ascending and descending aorta in all participants and quantified using Agatston's score. Multivariable Cox proportional hazards regression models were used to study the associations between TAC and incident CHD, CVD events and all-cause mortality. Likelihood ratio tests were used to compare prediction models including traditional risk factors plus TAC versus risk factors alone.

RESULTS

406 participants (11.9%) had TAC>0 at baseline. Over a median follow-up of 11.3 years, unadjusted event rates per 1000 person-years were higher in TAC>0 than in TAC = 0 participants: CHD 2.18 vs. 2.03; CVD 6.85 vs. 3.42; all-cause mortality 12.84 vs. 4.96. However, in multivariable Cox regression analyses adjusting for CVD risk factors, neither TAC>0, TAC>100 nor log(TAC+1) were independently associated with any of the study outcomes, nor improved their prediction compared to traditional risk factors alone (p value of likelihood ratio tests >0.05).

CONCLUSIONS

In a multi-ethnic, modern US population of asymptomatic individuals with CAC = 0 at baseline, the prevalence of TAC>0 was low, and TAC did not improve 10-year estimation of prognosis beyond traditional risk factors. In the presence of CAC = 0, measurement of TAC is unlikely to provide sufficient additional prognostic information to further improve risk assessment.

Aortic Arch Atheroma: Stroke Reduction in Cardiac Surgical Patients

Cardiac surgery is increasingly performed on elderly patients with extensive coronary artery abnormalities who have impaired left ventricular function, decreased physiologic reserve, and multiple comorbid conditions. Considerable numbers of these patients develop perioperative neurologic complications ranging from subtle cognitive dysfunction to more evident postoperative confusion, delirium, and, less commonly, clinically apparent stroke. Magnetic resonance imaging studies have elucidated that a considerable number of patients have new ischemic brain infarcts, particularly after conventional coronary artery bypass graft surgery. Mechanisms of cerebral injury during and after cardiac surgery are discussed. Intraoperative transesophageal echocardiography and epiaortic scanning for detection of atheromatous disease of the proximal thoracic aorta is paramount in identifying patients at high risk from neurologic injury. It is important to recognize that our efforts to minimize neurologic injury should not be limited to the intraoperative period. Particular efforts should be directed to temperature management, glycemia control, and pharmacologic neuroprotection extending into the postoperative period. Preoperative magnetic resonance angiography may be of value for screening patients with significant atheroma of the proximal thoracic aorta. It is likely that for patients with no significant atheromatous disease, conventional coronary artery revascularization is the most effective long-term strategy, whereas patients with atheromatous thoracic aorta may be better managed with beating heart surgery, hybrid techniques, or medical therapy alone. Patient stratification based on the aortic atheromatic burden should be addressed in future trials designed to tailor treatment strategies to improve long-term outcomes of coronary heart disease and reduce the risks of perioperative neurologic injury.

Management of the Ascending Aorta in Routine Cardiac Surgery

It is well known that subtle neurologic and neuropsychologic adverse effects are associated with cardiac surgery. Microgaseous emboli may arise from the cardiac pulmonary bypass apparatus; however, most particulate emboli arise from the ascending aorta. Atherosclerosis of the ascending aorta may effect up to 38% of cardiac surgical patients greater than 50 years of age. In addition to avoiding cardiopulmonary bypass with off-pump procedures, avoiding manipulation of the ascending aorta in any way is also associated with a reduction in embolic complications. Epiaortic scanning is the most accurate way to assess the location and severity of atheromata in the ascending aorta. Management of the atheromatous ascending aorta may include changes to cannulation options for cardiopulmonary bypass, such as femoral or axillary cannulation. Complete avoidance of the cross-clamp may be entertained. Aorta cannulae incorporate a number of filtration and deflection devices that may offer some protection to the brachiocephalic vessels. In some cases, replacement of the ascending aorta under deep hypothermic circulatory arrest is appropriate. Avoidance of the ascending aorta by using arterial revascularization as sequential or Y grafts, or placing proximal anastomoses on the subclavian arteries, may allow for complete revascularization without touching the ascending aorta. A full appreciation of the information obtained with epiaortic scanning or transesophageal echocardiography allows for decisions to be made to tailor each procedure to the patient's unique needs and circumstances for optimal outcomes.

Applied Neuromonitoring and Improving CNS Outcomes

Despite an overall decrease in perioperative morbidity and mortality, evidence of some degree of central nervous system dysfunction associated with coronary artery bypass graft (CABG) surgery—with or without cardiopulmonary bypass— has steadily mounted. From preoperative studies of CABG patients, it is apparent that over 50% of patients who present for cardiac surgery have evidence of either extracranial or intracranial atherosclerotic disease. Patient-specific factors thus have a fundamental impact on the risks of a brain injury developing after CABG surgery. Cerebral embolization and/or ischemic hypoperfusion are the most likely etiologic mechanisms for perioperative brain injury associated with cardiac surgery, and these factors are closely interrelated. Various monitoring techniques can decrease risk of intraoperative cerebral embolization and hypoperfusion and are associated with improved outcomes. Ultrasound guided aortic instrumentation (epiaortic scanning) can markedly decrease atheroembolic load and risk of stroke. Unrecognized sources of microgaseous emboli, including air entrainment from surgical purse string sutures and perfusionist interventions, can be identified and reduced by transcranial Doppler monitoring. Cerebral hypoperfusion from unrecognized cerebral venous obstruction, inadequate mean arterial pressure, or from hypocapnic cerebral alkalosis can be identified by multimodality neuromonitoring using regional cerebral oxygen saturation and transcranial Doppler. Overall patient outcomes can be improved, and hospital length of stay shortened, by applied neuromonitoring techniques.

Strategies and Techniques for Neuroprotection in Coronary Artery Surgery

Patients undergoing coronary artery bypass grafting are at higher risk of neurologic events than demographi cally similar patients undergoing noncardiac surgery. Postoperative stroke has been shown to occur two to three times more frequently than in age-, gender-, and education-matched patients undergoing noncardiac vas cular or thoracic surgery. The incidence of more subtle brain syndromes, giving rise to symptoms of memory loss and cognitive deterioration as documented in up to 79% of coronary bypass patients, varies depending on whether prospective or retrospective data are analyzed, and whether or not serial cognitive testing is used, and is also significantly higher in coronary bypass patients. Various factors have been identified as causative in the genesis of perioperative neurologic injury in these pa tients. Although there is evidence that microgaseous and microparticulate emboli are instrumental in the production of postoperative cognitive impairment, the role of ascending aortic atherosclerosis is increasingly recognized as being the greatest single risk factor for postoperative stroke.

Pathophysiological Basis of CNS Injury in Cardiac Surgical Patients: Detection and Prevention

The current understanding of adverse central nervous system (CNS) events following cardiac surgery involves several identifiable, evidence-based mechanisms: athero-sclerotic emboli, microgaseous and microparticulate emboli, and hypoperfusion.1 Secondary factors, including patient co-morbidities and inherent genetic susceptibilities, as well as systemic inflammatory processes and a suboptimal metabolic milieu may interact to potentiate the extent of injury.2 In this review a number of these factors and their potential interactions will be explored with a view towards developing a comprehensive management strategy to minimize CNS injury.

Evaluation of coated oxygenators in cardiopulmonary bypass systems and their impact on neurocognitive function

Introduction: Coronary artery bypass graft surgery (CABG) using cardiopulmonary bypass (CPB) is assumed to be associated with a decline of neurocognitive functions. This study was designed to analyse the neurocognitive function of patients with coronary heart disease before and after CABG and to determine possible protective effects of oxygenator surface coating on neurological outcome.

Methods: Forty patients scheduled for selective CABG were prospectively randomized into two groups of 20 patients each according to the type of hollow-fibre membrane oxygenator used. Non-coated oxygenators (Group A) were compared to phosphorylcholine (PC)- coated oxygenators (Group B). A battery of six neurological tests was administered preoperatively, 7 - 10 days and 4 - 6 months after surgery.

Results: One patient of Group A suffered from a perioperative stroke and died on postoperative day 3, presumably because of sudden heart failure. Two patients of Group A (10%) developed a symptomatic transitory delirious psychotic syndrome (STPT) on postoperative days 3 and 5. None of the patients of Group B had perioperative complications. The test analysis revealed a trend of declined neurocognitive function early after CABG, but did not show any difference in neurocognitive outcome between the two groups.

Discussion: PC coating of the oxygenators did not show any significant benefit on neurocognitive function after CABG using CPB.

Association of Dietary Factors with Progression of AA in Stroke/TIA Patients

OBJECTIVE

To investigate the effect of dietary factors such as calorie intake and dietary fats on the progression of aortic arch atheroma (AA).

BACKGROUND

In stroke/TIA patients, progression of AA is associated with recurrent vascular events.

DESIGN/METHODS

Consecutive patients with measurable (>1 mm) AA atheroma on baseline transesophageal echocardiogram (TEE) evaluation consented to a protocol mandated follow-up TEE at 12 months. Patients that had adequate paired AA images were assessed for progression, defined as Δ ≥ 1 grade worsening (based on plaque thickness over 12 months). Stroke risk factors and fasting lipid profile were assessed at baseline. The patient's nutritional intake was measured at baseline using the Gladys Block Food Frequency Questionnaire.

RESULTS

One-hundred-nine patients (70 strokes, 33 TIAs) had sequential TEEs, of whom 27% (N=30) progressed and 73% (N=79) did not. Patients with progression had higher daily calorie (1778 ± 623 vs. 1378 ± 406 Calories, p=0.008), fat (76 ± 33 vs. 52 ± 23 grams, p=0.0002), carbohydrate (208 ± 78 vs. 169 ± 57 grams, p=0.01) and protein (73 ± 26 vs. 57 ± 21 grams, p=0.005) intake. On Further analysis among different fats showed a higher consumption of saturated fats (25 ± 12 vs. 17 ±8 grams, p=0.00051) as well as unsaturated fats (44 ± 20 vs. 30 ± 13 grams, p=0.002). These differences remained significant after we adjusted for the medication use. However the significance of these differences was attenuated after adjusting for the calorie intake. Cholesterol consumption did not differ between the progression and no-progression group (262 ± 125 vs. 213 ± 149 mg, p=0.2).

CONCLUSIONS/RELEVANCE

Calorie intake plays a significant role in the progression of AA. Further studies are needed to confirm these findings and determine the specific dietary modifications that may prevent AA progression and associated recurrent vascular events.

Usefulness of Neuron-Specific Enolase to Detect Silent Neuronal Ischemia After Percutaneous Coronary Intervention

Increased plasma levels of neuron-specific enolase (NSE) are related to damage of neurons and neuroendocrine cells. We aimed to investigate elevation of NSE after elective percutaneous coronary intervention (PCI) on the prediction of silent cerebral infarct (SCI). Study population consisted of 2 groups of patients. Group 1 included 92 consecutive patients with normal coronary angiograms, whereas group 2 consisted of 89 patients who underwent elective coronary stenting. NSE levels were studied before and 12 hours after the procedure. Elevation of >0.12 μg/L was considered as SCI. Forty-seven of 181 study patients (26%) had SCI after the procedure. NSE elevation was significantly more prevalent in patients with PCI than that of controls. Elevation of NSE was observed in 42% of patients who underwent elective PCI (n = 37) and 11% of the normal coronary artery group (n = 10) (p <0.001). The incidence of SCI was higher in active smokers and patients who had history of myocardial infarction (MI) (55% vs 10%, p <0.001 for active smokers and 40% vs 8%, p <0.001 for history of MI, respectively). Multivariate analysis demonstrated history of smoking (odds ratio [OR] 9.9; 95% confidence interval [CI] 3.7 to 26.9; p <0.001) and previous MI (OR 4.4; 95% CI 1.7 to 11.4; p = 0.01) as independent predictors of SCI. For patients who underwent elective PCI, NSE levels after procedure increases. Invasive coronary procedures have risk of SCIs, even in patients with normal coronary arteries. In conclusion, increased diagnosis of SCIs might improve understanding of their relation with invasive cardiac procedures, facilitate to prevent occurrence of silent microemboli and decrease the risk of adverse neurologic events.

Correlation of VEGF genetic polymorphisms and lipid profile to aortic calcification

BACKGROUND

Aortic calcification is developed due to accumulation of a large amount of calcium in the aorta of the heart and it is the leading cause of aortic valve replacement and third leading cause of cardiovascular disease. The purpose of this study was to investigate the relation between aortic calcification and VEGF SNPs (-2578C>A, -1154G>A and +936C>T) and to evaluate the association of these SNPs with biochemical parameter in relation to aortic calcification.

METHODS

Aortic calcification was diagnosed by examining the posteroanterior chest X-rays by a radiologist and graded into four groups. The real-time polymerase chain reaction with melting curve analysis in LightCycler was used to genotype the VEGF SNPs.

RESULTS

Among the VEGF SNPs, a significant genetic difference was found only between the aortic calcification and control group with VEGF SNP -2578C>A but haplotypes T-A-A of (+936/-1154/-2578) were significantly different in control and aortic calcification and could enhance the aortic calcification development. By regression analysis, it was found that age, hypertension, diabetes, dyslipidemia, and hyperhomocysteinemia were found significantly different with the different genotypes of VEGF SNPs which may induce aortic calcification development.

CONCLUSION

Age, hypertension, diabetes, dyslipidemia, and hyperhomocysteinemia were established as aggravating factors for the aortic calcification in association with different VEGF genotypes.

Aortic arch atheroma and the risk of stroke: a meta-analysis

BACKGROUNDS AND OBJECTIVES

Epidemiological studies have suggested that aortic atheroma may play a role in cerebral embolization; however, no meta-analysis was conducted to evaluate the relationship between aortic atheroma and risk of stroke. The aim of this study was to investigate the association between the presence of aortic atheroma and risk of stroke.

METHODS

We performed a comprehensive search of observational studies reporting the relationship between the presence of aortic atheroma and stroke using the PubMed, EMbase, the China National Knowledge Infrastructure database (CNKI), Chinese Technical Periodicals (VIP), and WanFang Data databases. Two reviewers independently assessed the eligibility and extracted data from the included studies. We performed the meta-analysis to estimate the strength of the association according to Meta-analysis of Observational Studies in Epidemiology (MOOSE) guideline and assessed the study quality by the Newcastle-Ottawa Scale (NOS).

RESULTS

We identified 12 eligible studies with 3918 participants. The scores of the NOS of the included studies ranged from 5 to 9. The pooled estimate of strength of the association between the presence of aortic atheroma and stroke was statistical significant (OR = 3.93, 95%CI 2.86 to 5.40). In subgroup analysis according to plaques' morphology, complex aortic atheroma had significantly higher (OR = 5.90, 95%CI 4.14 to 8.41) risk of stroke than protruding atheroma (OR = 3.75, 95%CI 3.05 to 4.61).

CONCLUSIONS

This study indicated that aortic atheroma significantly increased the risk of stroke by about four times. Patients with complex aortic atheroma have a higher risk of stroke than protruding atheroma.

Embolic strokes of undetermined source: the case for a new clinical construct

Cryptogenic (of unknown cause) ischaemic strokes are now thought to comprise about 25% of all ischaemic strokes. Advances in imaging techniques and improved understanding of stroke pathophysiology have prompted a reassessment of cryptogenic stroke. There is persuasive evidence that most cryptogenic strokes are thromboembolic. The thrombus is thought to originate from any of several well established potential embolic sources, including minor-risk or covert cardiac sources, veins via paradoxical embolism, and non-occlusive atherosclerotic plaques in the aortic arch, cervical, or cerebral arteries. Accordingly, we propose that embolic strokes of undetermined source are a therapeutically relevant entity, which are defined as a non-lacunar brain infarct without proximal arterial stenosis or cardioembolic sources, with a clear indication for anticoagulation. Because emboli consist mainly of thrombus, anticoagulants are likely to reduce recurrent brain ischaemia more effectively than are antiplatelet drugs. Randomised trials testing direct-acting oral anticoagulants for secondary prevention of embolic strokes of undetermined source are warranted.

Coronary artery bypass grafting: Part 2--optimizing outcomes and future prospects

Since first introduced in the mid-1960s, coronary artery bypass grafting (CABG) has become the standard of care for patients with coronary artery disease. Surprisingly, the fundamental surgical technique itself did not change much over time. Nevertheless, outcomes after CABG have dramatically improved over the first 50 years. Randomized trials comparing percutaneous coronary intervention (PCI) to CABG have shown converging outcomes for select patient populations, providing more evidence for wider use of PCI. It is increasingly important to focus on the optimization of the short- and long-term outcomes of CABG and to reduce the level of invasiveness of this procedure. This review provides an overview on how new techniques and widespread consideration of evolving strategies have the potential to optimize outcomes after CABG. Such developments include off-pump CABG, clampless/anaortic CABG, minimally invasive CABG with or without extending to hybrid procedures, arterial revascularization, endoscopic vein harvesting, intraprocedural epiaortic scanning, graft flow assessment, and improved secondary prevention measures. In addition, this review represents a framework for future studies by summarizing the areas that need more rigorous clinical (randomized) evaluation.

From accuracy to patient outcome and cost-effectiveness evaluations of diagnostic tests and biomarkers: an exemplary modelling study

BACKGROUND

Proper evaluation of new diagnostic tests is required to reduce overutilization and to limit potential negative health effects and costs related to testing. A decision analytic modelling approach may be worthwhile when a diagnostic randomized controlled trial is not feasible. We demonstrate this by assessing the cost-effectiveness of modified transesophageal echocardiography (TEE) compared with manual palpation for the detection of atherosclerosis in the ascending aorta.

METHODS

Based on a previous diagnostic accuracy study, actual Dutch reimbursement data, and evidence from literature we developed a Markov decision analytic model. Cost-effectiveness of modified TEE was assessed for a life time horizon and a health care perspective. Prevalence rates of atherosclerosis were age-dependent and low as well as high rates were applied. Probabilistic sensitivity analysis was applied.

RESULTS

The model synthesized all available evidence on the risk of stroke in cardiac surgery patients. The modified TEE strategy consistently resulted in more adapted surgical procedures and, hence, a lower risk of stroke and a slightly higher number of life-years. With 10% prevalence of atherosclerosis the incremental cost-effectiveness ratio was € 4,651 and € 481 per quality-adjusted life year in 55-year-old men and women, respectively. In all patients aged 65 years or older the modified TEE strategy was cost saving and resulted in additional health benefits.

CONCLUSIONS

Decision analytic modelling to assess the cost-effectiveness of a new diagnostic test based on characteristics, costs and effects of the test itself and of the subsequent treatment options is both feasible and valuable. Our case study on modified TEE suggests that it may reduce the risk of stroke in cardiac surgery patients older than 55 years at acceptable cost-effectiveness levels.

Thoracic aortic calcification and coronary heart disease events: the multi-ethnic study of atherosclerosis (MESA)

BACKGROUND

The presence and extent of coronary artery calcium (CAC) is an independent predictor of coronary heart disease (CHD) morbidity and mortality. Few studies have evaluated interactions or independent incremental risk for coronary and thoracic aortic calcification (TAC). The independent predictive value of TAC for CHD events is not well-established.

METHODS

This study used risk factor and computed tomography scan data from 6807 participants in the multi-ethnic study of atherosclerosis (MESA). Using the same images for each participant, TAC and CAC were each computed using the Agatston method. The study subjects were free of incident CHD at entry into the study.

RESULTS

The mean age of the study population (n=6807) was 62±10 years (47% males). At baseline, the prevalence of TAC and CAC was 28% (1904/6809) and 50% (3393/6809), respectively. Over 4.5±0.9 years, a total of 232 participants (3.41%) had CHD events, of which 132 (1.94%) had a hard event (myocardial infarction, resuscitated cardiac arrest, or CHD death). There was a significant interaction between gender and TAC for CHD events (p<0.05). Specifically, in women, the risk of all CHD event was nearly 3-fold greater among those with any TAC (hazard ratio: 3.04, 95% CI: 1.60-5.76). After further adjustment for increasing CAC score, this risk was attenuated but remained robust (HR: 2.15, 95% CI: 1.10-4.17). Conversely, there was no significant association between TAC and incident CHD in men. In women, the likelihood ratio chi square statistics indicate that the addition of TAC contributed significantly to predicting incident CHD event above that provided by traditional risk factors alone (chi square=12.44, p=0.0004) as well as risk factors+CAC scores (chi square=5.33, p=0.02). On the other hand, addition of TAC only contributed in the prediction of hard CHD events to traditional risk factors (chi-square=4.33, p=0.04) in women, without contributing to the model containing both risk factors and CAC scores (chi square=1.55, p=0.21).

CONCLUSION

Our study indicates that TAC is a significant predictor of future coronary events only in women, independent of CAC. On studies obtained for either cardiac or lung applications, determination of TAC may provide modest supplementary prognostic information in women with no extra cost or radiation.

Complex atheromatosis of the aortic arch in cerebral infarction

In many stroke patients it is not possible to establish the etiology of stroke. However, in the last two decades, the use of transesophageal echocardiography in patients with stroke of uncertain etiology reveals atherosclerotic plaques in the aortic arch, which often protrude into the lumen and have mobile components in a high percentage of cases. Several autopsy series and retrospective studies of cases and controls have shown an association between aortic arch atheroma and arterial embolism, which was later confirmed by prospectively designed studies. The association with ischemic stroke was particularly strong when atheromas were located proximal to the ostium of the left subclavian artery, when the plaque was ≥ 4 mm thick and particularly when mobile components are present. In these cases, aspirin might not prevent adequately new arterial ischemic events especially stroke. Here we review the evidence of aortic arch atheroma as an independent risk factor for stroke and arterial embolism, including clinical and pathological data on atherosclerosis of the thoracic aorta as an embolic source. In addition, the impact of complex plaques (≥ 4 mm thick, or with mobile components) on increasing the risk of stroke is also reviewed. In non-randomized retrospective studies anticoagulation was superior to antiplatelet therapy in patients with stroke and aortic arch plaques with mobile components. In a retrospective case-control study, statins significantly reduced the relative risk of new vascular events. However, given the limited data available and its retrospective nature, randomized prospective studies are needed to establish the optimal secondary prevention therapeutic regimens in these high risk patients.