Postoperative stroke in cardiac surgery is related to the location and extent of atherosclerotic disease in the ascending aorta

Benefits of prophylactic carotid revascularization in patients with asymptomatic carotid artery stenosis undergoing coronary artery bypass surgery: A narrative review

Patients undergoing coronary artery bypass grafting (CABG) are at increased risk of perioperative stroke. Carotid atherosclerosis has been identified as an independent risk factor for stroke during and in the early postoperative period of cardiac surgery. However, the pathogenesis of peri-CABG stroke is multifactorial and frequently involves other noncarotid causes, such as cardiac emboli and aortic atheroma. Therefore, routine population-wide screening of carotid stenosis is not recommended, but target screening of patients at high risk of carotid-related perioperative stroke can have benefits. Carotid duplex sonography is recommended as an initial screening tool. Elimination of carotid stenosis before cardiac surgery is indicated in patients in whom carotid atherosclerosis is suspected to be the primary contributor to perioperative stroke. In patients with advanced carotid atherosclerosis, an individualized revascularization approach, including simultaneous or staged procedures, is advocated. The prevailing consensus is that synchronous surgery is safer than staged procedures. Carotid artery stenting represents a less invasive alternative, but its role in high-risk patients requires further investigation. In conclusion, the risk of perioperative stroke in patients undergoing CABG involves different factors, and carotid artery stenosis is involved in its pathogenesis only in some patients. Therefore, individualized approaches and careful consideration of patient risk factors are essential in determining the need for carotid screening and revascularization before CABG.

Stroke outcomes following cardiac and aortic surgery are improved by the involvement of a stroke team

OBJECTIVES

Post-cardiac and aortic surgery stroke is often underreported. We detail our single-centre experience the following introduction of comprehensive consultant-led daily stroke service, to demonstrate the efficacy of a stroke team in recovery from stroke following cardiac and aortic surgeries.

METHODS

This retrospective, single-centre observational cohort study analysed consecutive patients undergoing cardiac and aortic surgery at our institution from August 2014 to December 2020. Main outcomes included stroke rate, predictors of stroke, and neurological deficit resolution or persistence at discharge and clinic follow-up.

RESULTS

A total of 12,135 procedures were carried out in the reference period. Among these, 436 (3.6%) suffered a stroke. Overall survival to discharge and follow-up were 86.0% and 84.0% respectively. Independent risk factors for post-operative stroke included advanced age (OR 1.033, 95% CI [1.023, 1.044], p < .001), female sex (OR 1.491, 95% [1.212, 1.827], p < .001), history of previous cardiac surgeries (OR 1.670, 95% CI [1.239, 2.218], p < .001), simultaneous coronary artery bypass graft + valve procedures (OR 1.825, 95% CI [1.382, 2.382], p < .001) and CPB time longer than 240 min (OR 3.384, 95% CI [2.413, 4.705], p < .001). Stroke patients managed by the multidisciplinary team demonstrated significantly higher rates of survival at discharge (87.3% vs. 61.9%, p = .001).

CONCLUSIONS

Perioperative stroke can be debilitating immediately long term. The involvement of specialist stroke teams plays a key role in reducing the long-term burden and mortality of this condition.

Preoperative Chest Computed Tomography Screening Reduces the Perioperative Stroke Rate in Patients at Risk of Aortic Calcification

OBJECTIVES

We evaluated the effect of preoperative chest computed tomography (CT) screening on the perioperative stroke rate in cardiosurgical patients at risk of aortic calcification.

METHODS

Between May 2019 and April 2020, 129 patients at risk of aortic calcification underwent non-contrast chest CT screening before their procedure. They were assigned to Group 1 and compared with a historical Group 2, who were treated the previous year without a preoperative CT scan. The primary endpoint was to determine postoperative stroke occurrence. The secondary outcomes were the rate reintubation/tracheostomy, the length of hospital stay, and any change in surgical strategy based on the CT findings.

RESULTS

Groups 1 and 2 comprised 129 and 261 patients, respectively. Group 1 had a lower left ventricular ejection fraction, less carotid stenosis, a history of carotid endarterectomy, and a longer cross-clamp time. The surgical strategy was changed for 6 patients in Group 1. Group 1 had a significantly lower stroke rate. No significant differences were observed in reintubation and tracheostomy rates, or length of hospital stay. Lack of CT screening, age, aortic valve surgery, aortic surgery, and rethoracotomy were identified as independent risk factors for a stroke.

CONCLUSIONS

Preoperative non-contrast chest CT screening of patients at risk of aortic calcification reduces postoperative stroke through adaptation of the surgical approach and should be used routinely in these patients.

Preoperative Nonselective Chest Computed Tomography Prior to Primary Cardiac Surgery Results in Meaningful Change to Surgical Management: Systematic Review and Pooled Prevalence Meta-Analysis

BACKGROUND

Routine screening chest computed tomography (CT) prior to primary cardiac surgery is advocated by some surgeons due to the purported benefits of identifying significant aortic calcification that impacts ongoing management, such as performing anaortic off-pump surgery or adjusting cannulation strategy. Additionally, axial imaging can identify incidental findings that may require concomitant or staged procedures such as ascending aortic dilatation or pulmonary lesions. The objective of this study was to quantify the impact that nonselective chest CT prior to primary cardiac surgery had on subsequent management.

METHOD

A systematic review and pooled prevalence meta-analyses were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Included studies performed non-selective chest CT prior to primary cardiac surgery.

RESULTS

A total of eight studies, including 2,250 patients were included. The rate of mortality and stroke was low (1% and 2%, respectively). Calcification of the ascending aorta was identified in 15% of patients (95% confidence interval [CI] 5.0-26.0). A significant change to the surgical plan such as cannulation strategy, off-pump surgery, cancellation, or an additional procedure was required in 7% (95% CI 2.0-12.0). Clinically relevant incidental findings requiring in-patient management or follow-up were identified in 10% (95% CI 6.0-14.0).

CONCLUSIONS

Nonselective CT chest prior to primary cardiac surgery identifies clinically relevant findings that result in a modification of the surgical plan in a significant population of patients to address the risk of stroke associated with aortic calcification as well as the identification of important incidental findings such as pulmonary lesions.

Perioperative and Long-Term Outcomes in Patients Undergoing Synchronous Carotid Endarterectomy and Coronary Artery Bypass Grafting: A Single-Center Experience

INTRODUCTION

Patients requiring coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA) can be managed with staged (CEA before CABG), reverse staged (CABG before CEA) or synchronous treatment. This single-center retrospective study evaluated the outcomes in patients undergoing planned synchronous CEA and CABG.

METHODS

Between 2000 and 2020 a total of 185 patients with symptomatic triple-vessel or left main coronary artery disease associated with 70-99% asymptomatic or 50-99% symptomatic uni- or bilateral internal carotid artery (ICA) stenosis underwent synchronous CEA and CABG at our institution. Study endpoints were defined as mortality, stroke and myocardial infarction at 30 days. Additionally, the composite endpoint of these events was investigated.

RESULTS

At 30 days, mortality, stroke and myocardial infarction rates were 5.9%, 8.1% (permanent [unresolved deficit at discharge] 5.4%) and 3.8%, respectively, and the composite endpoint was reached in 13.0% of patients. Patients suffering from a stroke more frequently had a contralateral 70-99% ICA stenosis (60.0% vs. 17.3%; p < 0.001), peripheral artery disease (73.3% vs. 38.9%; p = 0.013) and prolonged cardiopulmonary bypass time (mean 119 ± 62 min vs. 84 ± 29 min; p = 0.012). Multivariate logistic regression analysis revealed the duration of cardiopulmonary bypass (odds ratio [OR] 1.024; 95% confidence interval [CI] 1.002-1.046; p = 0.034), a history of type 2 diabetes mellitus (OR 5.097; 95% CI 1.161-22.367; p = 0.031) and peripheral artery disease (OR 5.814; 95% CI 1.231-27.457; p = 0.026) as independent risk factors for reaching the composite endpoint.

CONCLUSION

Patients undergoing synchronous CEA and CABG face an elevated risk of perioperative cardiovascular events, particularly an increased stroke risk in patients with symptomatic and bilateral ICA stenosis. Graphical Abstract available for this article.

Incidence Rate of Post Coronary Artery Shunt Complications; Age Dependent!

BACKGROUND

Numerous complications, such as postoperative arrhythmia and stroke, have been observed following coronary artery bypass graft (CABG) surgery.

AIMS

This study sought to examine the impact of aging on the incidence of post-coronary artery shunt complications.

OBJECTIVES

Aging is a physiological process experienced by every living cell, beginning early in development. Age plays a crucial role in determining postoperative complications, including those related to CABG.

MATERIALS AND METHODS

A retrospective analysis was conducted on 290 patients who underwent CABG at the Mordovian Republic Hospital between 2017 and 2021. The sample was divided into two age-based groups: the first group comprised 126 patients (mean age range: 55.21-60.00), and the second group included 163 patients (mean age range: 66.11-80.00). Statistical analyses employed in this study encompassed descriptive statistics, Chi-square test, T-test, one-way ANOVA test, ROC analysis, and Pearson correlation using Statistica 12 software.

RESULTS

Elderly patients in the second group demonstrated a higher incidence of post-CABG arrhythmia (p < 0.012528). Moreover, the second group experienced markedly longer ICU and total hospitalization days following CABG, with p-values of less than 0.000000 and 0.000072, respectively. Notably, elderly individuals in the second group faced an increased risk of developing psychosis after CABG surgery (p < 0.007379). Furthermore, psychosis was found to be significantly associated with longer ICU hospitalization (p < 0.000140). Postoperative stroke occurred more frequently among the elderly (second group) with a p-value of less than 0.037736. Consequently, postoperative stroke was associated with extended ICU hospitalization (p < 0.000747). The usage of internal thoracic arteries (ITAs) was lower among the elderly (second group), with a p-value of less than 0.016145. Regarding correlations, a direct association was observed between age and ICU days, total hospitalization days, and the number of complications, with correlation coefficients (r) of 0.189046, 0.141415, and 0.138565, respectively.

CONCLUSION

Elderly individuals in the second group who undergo CABG face a greater risk of developing psychosis, arrhythmia, prolonged total and ICU hospitalization, and stroke. The presence of arrhythmia, which is commonly observed in patients aged 63 years and older, significantly affects total hospitalization days. The number of complications is influenced by age, cardiopulmonary bypass (CPB) time, aortic cross-clamp time, ICU hospitalization, and total hospitalization duration.

Routine preoperative screening computed tomography of the thorax for cardiac surgery

Introduction

This study aimed to evaluate the role of screening computed tomography (CT) of the thorax in cardiac surgery by analysing the presence of CT aortic calcifications in association with changes in operative strategy and postoperative stroke, and the CT features of emphysema with development of pneumonia.

Methods

All patients who underwent cardiac surgery from January 2013 to October 2017 by a single surgeon were retrospectively studied. Patients who underwent screening CT thorax before cardiac surgery (CT group) were compared to those who did not (no CT group). Multivariate subgroup analyses were performed to determine significant association with postoperative outcomes.

Results

A total of 392 patients were included, of which 156 patients underwent preoperative screening CT thorax. Patients in the CT group were older (63.9 vs. 59.0 years, P = 0.001), had fewer recent myocardial infarctions preoperatively (41% vs. 56.4%, P = 0.003) and had better ejection fraction (>30%; P = 0.02). Operative strategy was changed in 4.3% of patients, and 4.9% of patients suffered stroke postoperatively. The presence of CT aortic calcifications was significantly associated with change in operative strategy (P = 0.016) but not with postoperative stroke (P = 0.33). Age was an independent risk factor for change in operative strategy among patients with CT thorax (P = 0.02). Multivariate age-adjusted analysis showed only palpable plaque to be significantly associated with change in operative strategy (P < 0.001). None of the patients with CT emphysema features developed pneumonia.

Conclusion

The results of this study do not support routine use of preoperative screening CT thorax. Contrasted CT may be advisable in older patients and for other operative planning purposes.

The Rationalisation of Intra-Operative Imaging During Cardiac Surgery: A Systematic Review

INTRODUCTION

One critical complication of cardiac surgery is cerebrovascular accidents (CVAs). Ascending aorta atherosclerosis poses a significant risk of embolisation to distal vessels and to cerebral arteries. Epi-aortic ultrasonography (EUS) is thought to offer a safe, high-quality accurate visualisation of the diseased aorta to guide the surgeon on the best surgical approach to the planned procedure and potentially improve neurological outcomes post-cardiac surgery.

METHOD

The authors conducted a comprehensive search of PubMed, Scopus and Embase. Studies that reported on epi-aortic ultrasound use in cardiac surgery were included. Major exclusion criteria were: (1) abstracts, conference presentations, editorials, literature reviews; (2) case series with <5 participants; (3) epi-aortic ultrasound in trauma or other surgeries.

RESULTS

A total of 59 studies and 48,255 patients were included in this review. Out of the studies that reported patient co-morbidities prior to cardiac surgery, 31.6% had diabetes, 59.5% had hyperlipidaemia and 66.1% had a diagnosis of hypertension. Of those that reported significant ascending aorta atherosclerosis found on EUS, this ranged from 8.3% of patients to 95.2% with a mean percentage of 37.8%. Hospital mortality ranged from 7% to 13%; four studies reported zero deaths. Long-term mortality and stroke rate varied significantly with hospital duration.

CONCLUSION

Current data have shown EUS to have superiority over manual palpation and transoesophageal echocardiography in the prevention of CVAs following cardiac surgery. Yet, EUS has not been implemented as a routine standard of care. Extensive adoption of EUS in clinical practice is warranted to aid large, randomised trials before making prospective conclusions on the efficacy of this screening method.

The routine use of preoperative non-contrast chest computerized tomography and carotid arteries Doppler prior to cardiac surgery

Introduction

There is no consensus as to which patients should undergo Non-Contrast Chest Computerized Tomography (NCCCT) and carotid arteries Doppler (CD) prior to cardiac surgery. The objective of this study was to examine whether preoperative imaging modalities provide clinical benefits and a change in surgical strategy.

Methods

We routinely performed NCCCT and CD in all non-urgent cardiac surgery patients. Major NCCCT/CD findings related to cardiovascular findings (aortic calcification/atherosclerosis, carotid artery plaque/stenosis), or other incidental findings (lung kidney, thyroid, adrenal, gastrointestinal sites etc.) were documented. The results were divided into 3 categories: (A) findings requiring both changes in surgical strategy and post-operative evaluation/treatment; (B) findings requiring changes in surgical strategy, but not requiring a specific post-operative evaluation/treatment; (C) findings not requiring changes in surgical strategy but requiring post-operative evaluation/treatment.

Results

In this cohort, 93 (18.6%) out of 500 patients had significant cardiac and extra-cardiac findings on NCCCT and/or CD. Among the 93 patients with significant findings, 33.33% (31 patients, 6.2% of all patients) were in group A, 7.5% (7 patients, 1.4% of all patients) were in group B, and 59.14% (55 patients, 11% of all patients) were in group C. Change in surgical strategies included, for example, switching from planned on-pump Coronary Artery Bypass Graft surgery (CABG) to off-pump CABG and performing additional procedures to the originally planned heart surgery.

Conclusion

Routine preoperative NCCCT and CD evaluation in all non-urgent cardiac surgical patients is an effective measure for uncovering cardiac and extra-cardiac findings prior to surgery.

Use of computed tomography (CT) for preoperative planning in patients undergoing coronary artery bypass grafting (CABG)

Surgical planning for coronary artery bypass grafting (CABG) can be enhanced with the use of computed tomographic (CT) imaging to better understand the surgical field for optimal conduct of the case as well as risk assessment for outcomes. CABG via primary sternotomy, redo sternotomy, and minimally-invasive thoracotomy each pose unique surgical considerations and risks that can be better characterized with a preoperative CT scan. CT and CT angiographic (CTA) techniques with or without intravenous (IV) contrast can provide a noninvasive assessment of the vascular and bony structures and direct surgical planning techniques. Herein we discuss the role of CT/CTA imaging of the chest in preoperative planning of different strategies of CABG.

Left main coronary disease: evolving management concepts

Remarkable advances in the management of coronary artery disease have enhanced our approach to left main coronary artery (LMCA) disease. The traditional role of coronary artery bypass graft surgery has been challenged by the less invasive percutaneous coronary interventional approach. Additionally, major strides in optimal medical therapy now provide a rich menu of treatment choices in selected circumstances. Although a LMCA stenosis >70% is an acceptable threshold for revascularization, those patients with a LMCA narrowing between 40 and 69% present a more complex scenario. This review examines the relative merits of the different treatment options, addresses key diagnostic and therapeutic unknowns, and identifies future work likely to advance progress.

Predictors and clinical outcomes of post-coronary artery bypass grafting cerebrovascular strokes

BACKGROUND

Despite the improved medical and surgical managements, still there is a significant risk of developing acute cerebrovascular strokes after coronary artery bypass grafting (CABG). Our objectives were to study the immediate and long-term outcomes after CABG and to identify the possible predictors of post-CABG strokes.

RESULTS

Between January 2016 and August 2020, 410 adult patients, mostly males (82.2%), were retrospectively enrolled after CABG. Acute postoperative strokes occurred in 31 (7.5%) patients; of them, 30 (96.8%) patients had ischemic stroke, while 1 (3.2%) had hemorrhagic stroke. Mechanical thrombectomy was done in two cases. The patients who developed acute cerebral stroke had significantly higher admission (p = 0.02) and follow-up (p < 0.001) SOFA scores, higher arterial blood lactate level (p < 0.001), longer hospitalization (p < 0.001) and more hospital mortality (p < 0.001) compared with the patients who did not develop stroke. Kaplan-Meier curves for 5-year mortality showed increased risk in those patients with postoperative stroke (HR: 23.03; 95% CI: 6.10-86.92, p < 0.001). After multivariate regression, the predictors of early postoperative stroke were carotid artery stenosis (CAS), postoperative atrial fibrillation, cardiopulmonary bypass time, prior cerebral stroke, admission SOFA score and chronic kidney disease (CKD). The predictors of late cerebrovascular stroke were CAS, combined CABG and valve surgery, CKD, atrial fibrillation, prior stroke and HbA1c.

CONCLUSIONS

The development of post-CABG acute cerebrovascular stroke is associated with longer hospitalization, multiple morbidities and increased mortality. Careful assessment and management of risk factors especially atrial fibrillation and carotid artery stenosis should be implemented to decrease this substantial complication after CABG.

Concomitant anaortic OPCAB and transfemoral TAVR for high-risk patients: A case series

BACKGROUND

Combined on-pump coronary artery bypass (ONCAB) and surgical aortic valve replacement (SAVR) is the treatment of choice for concomitant severe aortic stenosis and coronary artery disease not amenable to percutaneous coronary intervention. Extensive aortic calcification and atheromatous disease may prohibit cardiopulmonary bypass and aortic cross-clamping. In these cases, anaortic off-pump coronary artery bypass (OPCAB) is a Class I (EACTS 2018) and Class IIA (AHA 2021) indication for surgical coronary revascularization. Transcatheter aortic valve replacement (TAVR) has similar benefits when compared with SAVR for this population (Partner 2 & 3). Herewith we describe a case series of concomitant Anaortic OPCAB and TAVR via the transfemoral approach for patients with coronary artery and valve disease considered too high risk for traditional coronary artery bypass grafting and SAVR due to severe aortic disease.

METHODS/RESULTS

Eight patients underwent anaortic OPCAB and transfemoral TAVR during the same anesthetic in a hybrid operating room. Seven patients with multivessel disease had anaortic OPCAB via a sternotomy using composite grafts, one patient with LAD disease had anaortic OPCAB using a Da Vinci-assisted MIDCAB approach. All patients then had an Edwards Sapien 3 TAVR placed percutaneously via the common femoral artery. There was no 30 mortality or CVA in the series and all patients were discharged to home or a rehabilitation facility on Day 4-13.

CONCLUSIONS

Combined anaortic OPCAB and transfemoral TAVR is a safe and feasible approach to treating concomitant extensive coronary artery disease and severe aortic stenosis. The aortic no-touch technique provides benefits in the elderly high-risk patients by reducing the risk of postoperative myocardial infarction and cerebrovascular stroke.

Mortality Reduction After a Preincision Safety Check Before Cardiac Surgery: Is It the Aorta?

OBJECTIVES

The introduction and use of a preincision safety check were associated with lower mortality after mixed adult cardiac surgery; however, an explanatory mechanism is lacking. Stroke, one of the most severe complications after cardiac surgery, with high mortality, may be reduced by adapting the surgical handling of the ascending aorta. This study assessed the prevalence and predictors of this adaptation after a preincision safety check and the subsequent effect on outcome.

DESIGN

A prospective, single-center, observational study comparing adaptation with no-adaptation. The primary outcome measure was 30-day mortality. Multivariate analyses were performed to determine independent predictors of adaptation. To study the effect of adaptation on outcome, a propensity score-matched cohort was constructed in a 1:3 intervention:control ratio.

SETTING

At Isala Zwolle (NL), a large, nonacademic teaching hospital.

PARTICIPANTS

All consecutive cardiac surgery procedures from 2012 until 2015, including 4,752 surgeries.

INTERVENTIONS

The adaptation of surgical handling of the ascending aorta.

MEASUREMENTS AND MAIN RESULTS

In 283 cardiac surgeries (5.9%), adaptation was indicated. The most important independent predictors for adaptation were extracardiac atherosclerosis, current smoking, and increasing age. In the propensity score-matched cohort consisting of 1,069 procedures, there were no significant differences in outcome. After correction for propensity score, the hazard ratio of adaptation for 30-day mortality was 1.8 (0.85-3.79).

CONCLUSIONS

The adaptation of aortic surgical handling after a preincision safety check was necessary for 5.9% of cardiac surgeries, with extracardiac atherosclerosis as the strongest predictor. Outcome was not significantly different between patients with and without adaptation. Although promising, it remains unclear whether adaptation may fully explain mortality reduction after the use of a preincision safety check.

Vascular biomechanics and molecular disease activity in the thoracic aorta: a novel imaging method

AIMS

The influence haemodynamics have on vessel wall pathobiology in aortic disease is incomplete. This aim of this study was to develop a repeatable method for assessing the relationship between aortic wall shear stress (WSS) and disease activity by fusing 4D flow cardiovascular magnetic resonance (CMR) with hybrid positron emission tomography (PET).

METHODS AND RESULTS

As part of an ongoing clinical trial, patients with bicuspid aortic valve (BAV) were prospectively imaged with both 18F-sodium fluoride (18F-NaF) PET, a marker of calcification activity, and 4D flow CMR. We developed novel software allowing accurate 3D co-registration and high-resolution comparison of aortic peak systolic WSS and 18F-NaF PET uptake (maximum tissue-to-background ratio). Intra-observer repeatability of both measurements was determined using Bland-Altman plots and intra-class correlation coefficients (ICCs). The relationship between localized WSS and 18F-NaF uptake was analysed using linear mixed-effect models. Twenty-three patients with BAV (median age 50 [44-55] years, 22% female) were included. Intra-observer repeatability for WSS (ICC = 0.92) and 18F-NaF (ICC = 0.91) measurements obtained within 1.4 ± 0.6 cm2 regions of interest was excellent. On multivariable analysis, 18F-NaF PET uptake was independently and negatively associated with WSS as well as diastolic blood pressure (both P < 0.05), adjusted for age.

CONCLUSION

Fused assessment of WSS and 18F-NaF PET uptake is feasible and repeatable, demonstrating a clear association between these two factors. This high spatial resolution approach has major potential to advance our understanding of the relationship between vascular haemodynamics and disease activity.

Hypothermic Fibrillatory Arrest During Coronary Artery Bypass Grafting in a Man With Calcified Aorta and Ventricular Fibrillation

A 67-year-old man undergoing coronary artery bypass grafting had aortic calcification that prohibited aortic cross-clamping. When ventricular fibrillation developed during surgery, we instituted hypothermic fibrillatory arrest to avoid aortic cross-clamping. In addition to our patient's case, we discuss the advantages and disadvantages of using hypothermic fibrillatory arrest during cardiac surgery.

Surgical strategies for severely atherosclerotic (porcelain) aorta during coronary artery bypass grafting

Porcelain aorta (PA) is an asymptomatic atherosclerotic disease, characterized by circumferential calcification throughout the whole perimeter of the aorta. It is seen in 2% to 9.3% of patients undergoing elective coronary artery bypass grafting (CABG) and makes manipulation of the ascending aorta impossible. It has been clearly shown that most emboli seen and detected during the CABG procedure occur during aortic cross-clamping and aortic side-clamping. Manipulation of porcelain or a severely atherosclerotic aorta increases the risk of perioperative stroke. The incidence of stroke after CABG is between 0.48% and 2.9%, and the risk is correlated with the extent and severity of the atherosclerotic disease. A conventional CABG procedure involves successive steps that include cannulation of the ascending aorta, application of a cross-clamp to the aorta, and partial clamping of the aorta to create the proximal anastomosis. Therefore in procedures that involve cannulation, clamping, or proximal anastomosis, and where aortic manipulation is inevitable, preassessment of the atherosclerotic aortic plaques is crucial. Although many surgeons still rely on intraoperative manual aortic palpation, this approach has very low sensitivity and underestimates the severity of the atherosclerotic illness. Imaging methods including preoperative computed tomography or intraoperative epiaortic ultrasonography enable modification of the surgical technique according to the severity of atherosclerosis. Various surgical techniques have been described to reduce the risk of atheroembolism that may lead to cerebrovascular events in patients with severely atherosclerotic ascending aorta. Anaortic or "no-touch" techniques that do not utilize aortic manipulation may significantly decrease the development of neurological complications by avoiding aortic maneuvers known to cause emboli. In cases where severe atherosclerotic disease or other factors preclude safe use of the ascending aorta, modifications in the surgical techniques, such as switching to different cannulation sites including the axillary/subclavian, femoral and innominate arteries, or using hypothermic ventricular fibrillation and in-situ pedicled arterial grafts, or performing proximal anastomoses at alternative anatomical locations will enable CABG operations to be performed safely with low morbidity and mortality rates in patients with porcelain aortas.

Intimal aortic atherosclerosis in cardiac surgery: surgical strategies to prevent embolic stroke

 

OBJECTIVES

Although the incidence of perioperative stroke after cardiac surgery gradually decreased over the last decades, there is much variation between centres. This review aimed to create a concise overview of the evidence on possible surgical strategies to prevent embolic stroke in patients with intimal aortic atherosclerosis.

METHODS

The PubMed and EMBASE databases were searched for studies on surgical management of aortic atherosclerosis and the association with perioperative stroke in cardiac surgery, including specific searches on the most common types of surgery. Articles were screened with emphasis on studies comparing multiple strategies and studies reporting on the patients’ severity of aortic atherosclerosis. The main findings were summarized in a figure, with a grade of the corresponding level of evidence.

RESULTS

Regarding embolic stroke risk, aortic atherosclerosis of the tunica intima is most relevant. Although several strategies in general cardiac surgery seem to be beneficial in severe disease, none have conclusively been proven most effective. Off-pump surgery in coronary artery bypass grafting should be preferred with severe atherosclerosis, if the required expertise is present. Although transcatheter aortic valve replacement is used as an alternative to surgery in patients with a porcelain aorta, the risk profile concerning intimal atherosclerosis remains poorly defined.

CONCLUSIONS

A tailored approach that uses the discussed alternative strategies in carefully selected patients is best suited to reduce the risk of perioperative stroke without compromising other outcomes. More research is needed, especially on the perioperative stroke risk in patients with moderate aortic atherosclerosis.

Flow analysis during mock circulation in normal and aortic arch aneurysm models through an aortic cannula toward the aortic arch and root

The aim of this study was to elucidate flow patterns of two different types of aortic cannulas inserted from the ascending aorta toward the aortic arch and root by mock circulation in a normal aortic arch and an aortic arch aneurysm model. Extracorporeal circulation was established using a centrifugal pump, a transparent glass normal aortic arch model, and an aortic arch aneurysm model for measurement by particle image velocimetry. The Stealthflow and Dispersion cannulas were used to elucidate the characteristics of the flow pattern and velocity under the condition of the cannula tip toward the aortic arch and aortic root. In the normal aortic arch model, high-velocity exit flow ranging from 0.7 to 0.8 m/s was detected in the proximal aortic arch by directing the cannula tip toward the aortic arch, whereas flow velocity in the aortic arch was < 0.2 m/s by directing the cannula tip toward the aortic root. In the aortic arch aneurysm model, high-velocity exit flow ranging from 0.5 to 0.8 m/s was detected in the aortic arch by directing the cannula tip toward the aortic arch, whereas flow velocity in the aortic arch was decreased to less than 0.2 m/s by directing the cannula tip toward the aortic root. Directing the aortic cannula tip toward the aortic root allowed the high-velocity exit flow to attenuate in velocity, so that flow velocity in the aortic arch was sufficiently reduced by reversed flow and vortex formation in both the normal and aortic arch aneurysm models.

Impact of standardized computed tomographic angiography for minimally invasive mitral and tricuspid valve surgery

Background

Femoral cannulation for extracorporeal circulation (ECC) is a standard procedure for minimally invasive cardiac surgery (MICS) of the atrio-ventricular valves. Vascular pathologies may cause serious complications. Preoperative computed tomography-angiography (CT-A) of the aorta, axillary and iliac arteries was implemented at our department.

Methods

Between July 2017 and December 2018 all MICS were retrospectively reviewed (n = 143), and divided into 3 groups.

Results

In patients without CT (n = 45, 31.5%) ECC was applied via femoral arteries (91.1% right, 8.9% left). Vascular related complications (dissection, stroke, coronary and visceral ischemia, related in-hospital death) occurred in 3 patients (6.7%). In patients with non-contrast CT (n = 35, 24.5%) only femoral cannulation was applied (94.3% right) with complications in 4 patients (11.4%). CT-angiography (n = 63, 44.1%) identified 12 patients (19.0%) with vulnerable plaques, 7 patients (11.1%) with kinking of iliac vessels, 41 patients (65.1%) with multiple calcified plaques and 5 patients (7.9%) with small femoral artery diameter (d ≤ 6 mm). In 7 patients (11.1%) pathologic findings led to alternative cannulation via right axillary artery, additional 4 patients (6.3%) were cannulated via left femoral artery. Only 2 patients (3.2%) suffered from complications.

Conclusions

CT-A identifies vascular pathologies otherwise undetectable in routine preoperative preparation. A standardized imaging protocol may help to customize the operative strategy.

Plaster pipes and crystalized graphite: Open transventricular transcatheter aortic valve replacement for failed mechanical aortic valve prostheses in the porcelain aorta

Patients with a true porcelain aorta and a failed mechanical aortic valve prosthesis have limited treatment options. Using a hybrid of an open trans-ventricular approach with peripheral cardiopulmonary bypass and integration of transcatheter techniques this challenge can be overcome. Trans-ventricular mechanical valve extraction (with transcatheter endovascular occlusion and cardioplegia) followed by direct ante-grade transcatheter heart valve implantation offers a potential solution to this conundrum. The procedure described is a novel technique that allows for the effective treatment of patients with failed mechanical surgical aortic valve prostheses in the setting of an inoperable porcelain aorta. In addition, a collaborative integrated multi-disciplinary heart team environment is required for the management of these complex patients.

Preoperative evaluation of aortic calcification by computed tomography in thoracic aortic disease

BACKGROUND

Computed tomography (CT) is a useful tool for the identification of calcified lesions in the aorta. However, no quantitative evaluation has been established to assess the applicability of simple anastomosis preoperatively. We conducted this retrospective study to establish a reference range of maximal CT attenuation values for application of simple anastomosis.

METHODS

A total of 122 consecutive patients underwent replacement of the thoracic aorta between 2007 and 2011, excluding those with acute aortic dissection. The patients were divided into two groups: those who underwent simple anastomosis (simple group: n = 105), and those who required endarterectomy before anastomosis (manipulation group: n = 17). The maximal CT attenuation values at the anastomosis site were calculated by imaging software.

RESULTS

The mean maximal CT attenuation values (Hounsfield unit [HU]) was significantly higher in the manipulation group (638.1 ± 269.5 [166-1304]) than in the simple group (94.7 ± 171.5 [0-790]; p < .0001). The maximal CT attenuation values enabled us to predict the simple anastomosis with the area under the receiver operating characteristic curve of 0.96 (p < .0001). The cut-off value was 325 HU (sensitivity 94.1%, specificity 81.7%). The 10-year survival rate was significantly lower in the manipulation group (11.8%) than in the simple group (43.2%). In the multivariate analysis, age (hazard ratio [HR]: 1.073), hypertension (HR: 2.382), and maximal CT attenuation values (HR: 1.001) were independently associated with long-term mortality.

CONCLUSIONS

Preoperative evaluation of the maximal CT attenuation values is a useful tool in predicting whether simple anastomosis is applicable or not. Maximal CT attenuation values is a risk factor for long-term mortality.

Preoperative Computed Tomography in the Adult Cardiac Surgery Patient

Increasingly, computed tomography is requested for preoperative planning prior to cardiac surgery. Common pathologies, such as aortic and mitral annular calcification, can influence the choice of surgical technique or approach. In this article, we present a case-based review of primary and reoperative sternotomies that focuses on the clinical relevance of the common pathologies and findings in pre-operative computed tomography images, with respect to surgical decision-making and management.

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.

The evolving role of the modern perfusionist: insights from transesophageal echocardiography

Transesophageal echocardiography is a relatively non-invasive, mobile, safe imaging technique that is ideal for providing real-time information on cardiac anatomy and function during heart surgery. The technology has evolved from two-dimensional to real-time three-dimensional imaging during cardiac procedures, which has significantly benefited preoperative planning, intraoperative guidance, evaluation, and postoperative follow-up. Transesophageal echocardiography may serve the clinical perfusionist by providing imaging guidance for identifying potential problems before cardiopulmonary bypass, guiding the proper placement of cannulas, monitoring cardiac performance on cardiopulmonary bypass, and providing useful feedback during weaning from cardiopulmonary bypass. Although the perfusionist should be able to understand all echocardiographic images and measurements in depth, perfusion-related echocardiographic information can or should be used to optimize the clinical practice of the modern perfusionist. Vice versa, whenever the perfusionist suspects a problem, the surgical team including the sonographer should verify this "clinical treat" by echocardiography whenever possible.

Clinical evaluation of a new dispersive aortic cannula

INTRODUCTION

Cerebral injury is a serious complication in open-heart surgery. Once it occurs, it causes significant disability and death. We developed a novel dispersive aortic cannula named the Stealth Flow cannula and used it as a standard aortic cannula in cardiopulmonary bypass. The aim of this study was to evaluate the efficiency of this aortic cannula.

METHODS

A total of 182 consecutive patients undergoing cardiac surgery using cardiopulmonary bypass were studied. The patients were divided into two groups: the Soft-Flow cannula group (n = 89) and the Stealth Flow cannula group (n = 93). Patients with a shaggy aortic arch were excluded from this study because the cannulae were inserted at the ascending aorta with a cannula tip directed toward the aortic root in these cases. Patients with multiple arterial perfusion sites were also excluded. Complications including early mortality, perioperative stroke, and intraoperative aortic injury were compared between the two groups.

RESULTS

Age, operative procedure, cardiopulmonary bypass time, and the Japan SCORE were not significantly different between the groups. In comparisons between the Stealth Flow and Soft-Flow groups, the incidences of early mortality, perioperative stroke, intraoperative aortic dissection, and all complications were 1.08% versus 1.12% (p = 0.98), 1.1% versus 2.2% (p = 0.53), 0% versus 1.1% (p = 0.33), and 1.1% versus 3.4% (p = 0.29), respectively. The incidence of major cardiovascular events, including early death, perioperative stroke, and aortic dissection, was not different.

CONCLUSIONS

The Stealth Flow cannula, which was designed based on our previous experimental study, contributed to reducing cerebral and aortic events as much as the Soft-Flow cannula in the present clinical study.

Cerebral atherosclerosis and early ischemic stroke after left-sided valve replacement surgery

OBJECTIVE

Studies have rarely investigated whether cerebral atherosclerosis increases the risk of stroke after valve replacement surgery. This study evaluated the influence of cerebral atherosclerosis on the risk of stroke after left-sided valve replacement surgery.

METHODS

Between 2005 and 2015, preoperative magnetic resonance angiography was performed for 2085 patients who underwent left-sided valve replacement surgery in a tertiary single center to assess intracranial and extracranial cerebral atherosclerosis. The severity was retrospectively assessed on the basis of the atherosclerosis score, determined by the number of steno-occlusions of the cerebral arteries and the degree of atherosclerosis. Associations between cerebral atherosclerosis and postoperative stroke (within 30 days) were evaluated; the overall influence of total cerebral atherosclerosis, and the individual effects of intracranial and extracranial cerebral atherosclerosis on the risk of postoperative stroke were assessed using multivariable models.

RESULTS

Preoperative cerebral atherosclerosis was identified in 626 (30.0%) patients, whereas intracranial cerebral atherosclerosis and extracranial cerebral atherosclerosis were identified in 367 (17.1%) and 412 (19.8%) patients, respectively. Stroke occurred in 54 (2.6%) patients, and the total cerebral atherosclerosis score was independently associated with an increased risk of stroke (odds ratio, 1.23; 95% confidence interval, 1.06-1.44). The intracranial cerebral atherosclerosis scores (odds ratio, 1.44; 95% confidence interval, 1.16-1.78), but not the extracranial cerebral atherosclerosis scores, independently predicted the incidence of stroke.

CONCLUSIONS

Intracranial cerebral atherosclerosis was an important predictor of postoperative stroke, suggesting the necessity of further studies on the feasibility of preoperative screening for cerebral atherosclerosis in patients undergoing left-sided valve replacement surgery.

Aortic calcifications on routine preoperative chest X-ray and perioperative stroke during cardiac surgery: a nested matched case-control study

OBJECTIVES

Perioperative stroke in cardiac surgery is most often embolic in origin. Preoperative chest X-ray (CXR) is routinely used amongst others to screen for relevant aortic calcification, a potential source of embolic stroke. We performed a nested matched case-control study to examine the relationship between aortic calcifications on CXR and the occurrence of embolic stroke.

METHODS

Among all consecutive patients undergoing cardiac surgery in our hospital between January 2014 and July 2017, we selected all patients with perioperative embolic stroke (cases). Controls, all patients without perioperative stroke, were matched on age, sex and type of surgery. All preoperative CXRs were scored for aortic calcifications (none, mild, severe) in the ascending aorta, arch, aortic knob and descending aorta.

RESULTS

Out of the 3038 eligible patients, 27 cases were detected and 78 controls were selected. In the stroke group, mild-to-severe calcifications were found least often in the ascending aorta [9% of patients, 95% confidence interval (CI) 1-29%] and most frequently in the aortic knob (63% of patients, 95% CI 44-78%). The distribution of aortic calcification was comparable in cases versus controls.

CONCLUSIONS

Calcification burden was comparable between the cases and their matched controls. In our study population, CXR findings on aortic calcification were not related to the risk of embolic stroke. In these patients, the correlation between findings on the preoperative CXR and the risk of stroke might, therefore, be too weak to use the CXR directly for the assessment of the safety of manipulating the ascending aorta during surgery.

Impact of Aortic Atherosclerosis Burden on Outcomes of Surgical Aortic Valve Replacement

BACKGROUND

Epiaortic ultrasound detects and localizes ascending aortic atherosclerosis. In this analysis we investigated the association between epiaortic ultrasound-based atheroma grade during surgical aortic valve replacement (SAVR) and perioperative adverse outcomes.

METHODS

SAVR patients in a randomized trial of 2 embolic protection devices underwent a protocol-defined 5-view epiaortic ultrasound read at a core laboratory. Aortic atherosclerosis was quantified with the Katz atheroma grade, and patients were categorized as mild (grade I-II) or moderate/severe (grade III-V). Multivariable logistic regression was used to estimate associations between atheroma grade and adverse outcomes, including death, clinically apparent stroke, cerebral infarction on diffusion-weighted magnetic resonance imaging, delirium, and acute kidney injury (AKI) by 7 and 30 days.

RESULTS

Precannulation epiaortic ultrasound data were available for 326 of 383 randomized patients (85.1%). Of these, 106 (32.5%) had moderate/severe Katz atheroma grade at any segment of the ascending aorta. Although differences in the composite of death, stroke, or cerebral infarction on diffusion-weighted magnetic resonance imaging by 7 days were not statistically significant, moderate/severe atheroma grade was associated with a greater risk of AKI by 7 days (adjusted odds ratio, 2.63; 95% confidence interval, 1.24-5.58; P = .01). At 30 days, patients with moderate/severe atheroma grade had a greater risk of death, stroke, or AKI (adjusted odds ratio, 1.97; 95% confidence interval, 1.04-3.71; P = .04).

CONCLUSIONS

Moderate/severe aortic atherosclerosis was associated with an increased risk of adverse events after SAVR. Epiaortic ultrasound may serve as a useful adjunct for identifying patients who may benefit from strategies to reduce atheroembolic complications during SAVR.

MDCT prior to median re-sternotomy in cardiovascular surgery: our experiences, infrequent findings and the crucial role of radiological report

Resternotomy (RS) is a common occurrence in cardiac surgical practice. It is associated with an increased risk of injury to old conduits, cardiac structures, catastrophic hemorrhage and subsequent high morbidity and mortality rate in the operating room or during the recovery period. To mitigate this risk, we evaluated the role of multidetector CT (MDCT) in planning repeat cardiac surgery. We evaluated sternal compartment abnormalities, sternal/ascending aorta distance, pre-reoperative assessment of the aorta (wall, diameters, lumen, valve), sternal/right ventricle distance, diaphragm insertion, pericardium and cardiac chambers, sternal/innominate vein distance, connection of the grafts to the predicted median sternotomy cut, graft patency and anatomic course, possible aortic cannulation and cross-clamping sites and additional non-cardiovascular significant findings. Based on the MDCT findings, surgeons employed tailored operative strategies, including no-touch technique, clamping strategy and cardiopulmonary bypass (CPB) via peripheral cannulation assisted resternotomy. Our experience suggests that MDCT provides information which contributes to the safety of re-operative heart surgery reducing operative mortality and adverse outcomes. The radiologist must be aware of potential surgical options, including in the report any findings relevant to possible resternotomy complications.

Neural network imaging to characterize brain injury in cardiac procedures: the emerging utility of connectomics

Cognitive dysfunction is a poorly understood but potentially devastating complication of cardiac surgery. Clinically meaningful assessment of cognitive changes after surgery is problematic because of the absence of a means to obtain reproducible, objective, and quantitative measures of the neural disturbances that cause altered brain function. By using both structural and functional connectivity magnetic resonance imaging data to construct a map of the inter-regional connections within the brain, connectomics has the potential to increase the specificity and sensitivity of perioperative neurological assessment, permitting rational individualized assessment and improvement of surgical techniques.

Distribution of Thoracic Aortic Calcifications in Patients Undergoing Coronary Artery Bypass Grafting

Background

In procedures involving surgical maneuvers such as cannulation, clamping, or proximal anastomosis where aortic manipulation is inevitable, a preliminary assessment of atherosclerotic plaques bears clinical significance. In the present study, our aim was to evaluate the frequency and distribution of aortic calcifications in patients undergoing coronary artery bypass grafting (CABG) surgery to propose a morphological classification system.

Methods

A total of 443 consecutive patients with coronary artery disease were included in this study. Preoperative non-contrast enhanced computed tomography images, in-hospital follow-up data, and patient characteristics were retrospectively evaluated.

Results

Whereas 33% of patients had no calcifications at any site in the aorta, 7.9%, 75.4%, and 16.7% had calcifications in the ascending aorta, aortic arch, and descending aorta, respectively. Focal small calcifications were the most common type of lesions in the ascending aorta (3.9%), whereas 9 patients (1.4%) had porcelain ascending aorta. We defined four types of patients with increasing severity and extent of calcifications.

Conclusions

Based on the frequency and distribution of calcifications in the thoracic aorta, we propose a classification system from least to most severe for coronary artery disease patients who are candidates for CABG.

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.

Frequency of abnormal findings on routine chest radiography before cardiac surgery

OBJECTIVE

Preoperative chest radiograph screening is widely used before cardiac surgery. The objective of this study was to investigate the frequency of abnormal findings on a routine chest radiograph before cardiac surgery.

METHODS

In this retrospective cohort study, 1136 patients were included. Patients were scheduled for cardiac surgery and underwent a preoperative chest radiograph. The primary outcome was the frequency of abnormalities on the chest radiograph. Secondary outcome was the effect of those abnormalities on surgery.

RESULTS

One half of the patients (570/1136; 50%) had 1 or more abnormalities on the chest radiograph. Most frequent abnormalities were cardiomegaly, aortic elongation, signs of chronic obstructive pulmonary disease, vertebral fractures or height loss, possible pulmonary or mediastinal mass, pleural effusion, and atelectasis. In 2 patients (2/1136; 0.2%), the chest radiograph led to postponement of surgery, whereas in none of the patients the surgery was cancelled. In 1 patient (1/1136; 0.1%) the surgical approach was altered and in 15 patients (15/1136; 1.3%) further analysis was performed without having an impact on the planned surgical approach.

CONCLUSIONS

Although abnormalities are frequently found on preoperative chest radiographs before cardiac surgery, change in clinical management with regard to planned surgery or surgical approach occurs infrequently.

'Porcelain aorta': a proposed definition and classification of ascending aortic calcification

Introduction

‘Porcelain aorta’ is listed in the second consensus document of the Valve Academic Research Consortium as a risk factor in aortic valve replacement. However, the extent of circumferential involvement is poorly defined with great variability in reported incidence. We present a simple, reproducible classification to describe the extent of aortic calcification and thus appropriately define ‘porcelain aorta’, aiding clinical decision-making and registry data collection.

Methods

175 consecutive CT aortograms were reviewed. The aorta was divided into three sections, and each section divided into quadrants. These were individually scored using a 5-point scale (0—no calcification, 5—complete contiguous calcification).

Results for each quadrant were summated for each segment to provide an indication of the distribution of calcification.

Results

Only one patient (0.6%) had a ‘true’ porcelain aorta, defined as contiguous calcification across all quadrants at any aortic level. Intraobserver and interobserver variation was excellent for the ascending aorta (K=0.85–0.88 and 0.81–0.96, respectively) while the interobserver variation in the transverse arch was good at 0.75.

Conclusions

Our data suggest the incidence of ‘true’ porcelain aorta may be significantly lower than reported in the literature. The predominance of calcification within the anterior wall of the proximal ascending aorta and the superior wall of the transverse arch may be clinically important. Application of this quick, simple and reproducible grading system, with no requirement for advanced software, may provide a tool to support accurate assessment of focal aortic calcification and its relationship to subsequent procedural risk.

Effectiveness and Safety of Transcatheter Aortic Valve Implantation for Aortic Stenosis in Patients With "Porcelain" Aorta

Surgical aortic valve replacement (SAVR) in patients with porcelain aorta is considered a high-risk procedure. Hence, transcatheter aortic valve implantation (TAVI) is emerging as the intervention of choice. However, there is a paucity of data directly comparing TAVI with SAVR in patients with porcelain aorta. We compared outcomes of TAVI versus SAVR in high-risk patients with porcelain between March 2012 and June 2015. The TAVI group included 54 patients, whereas 130 SAVR patients with porcelain aorta were identified (operated on between 2004 and 2015). Both groups were matched 1:1 based on the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score with a 0.5% a priori caliper, resulting in 52 matched pairs. The mean STS-PROM was 7.3 ± 3.9 for both groups (p = 0.98), whereas mean age was 77.5 years for TAVI and 78.8 years for SAVR (p = 0.46). Compared with SAVR, TAVI patients had lower operative mortality (3.8% vs 17.3%; p = 0.052), significantly shorter median intensive care unit (40 vs 107 hours; p < 0.001) and hospital (5 vs. 7 days; p < 0.001) length of stay (LOS), but similar postoperative stroke rates (7.7% vs 11.5%; p = 0.74). One-year unadjusted survival was 81.7% (95% confidence interval [CI]: 69.8% to 93.5%) in the TAVI group versus 71.2% (95% CI: 61.0% to 85.1%) in the SAVR group, p = 0.093. Cox proportional hazard modeling identified preoperative chronic kidney disease (hazard ratio: 2.63 [95% CI: 1.03 to 6.70]; p = 0.043) and SAVR (hazard ratio: 2.641 [95% CI: 1.07 to 6.51]; p = 0.035) as significant predictors for decreased survival. Overall, TAVI was associated with reduced operative mortality, increased survival, and shorter intensive care unit and hospital length of stay compared with SAVR in patients with porcelain aorta. This study demonstrates that TAVI is a safe intervention in this high-risk population.

SYNTAX score may predict the severity of atherosclerosis of the ascending aorta

Background

The objective of this study was to investigate the association of the coronary SYNTAX score with the degree of atherosclerosis of the ascending aorta in patients who underwent coronary artery bypass grafting (CABG).

Methods

A total of 152 patients (mean age 65 years, 66% male) were analyzed who underwent isolated CABG with both SYNTAX score and the intraoperative 5-point scale grading of the severity of atherosclerosis in the ascending aorta available. The patient were stratified into low, intermediate, and high SYNTAX score groups [≤22 (n=36), 22-33 (n=42), and ≥33 (n=76)].

Results

The mean SYNTAX score was 31±11. Patient demographics and comorbidity were comparable in each group. The prevalence of severe atherosclerosis (Grade ≥III) in the ascending aorta was 17.5% (n=27) in the whole population and was different in each group with higher prevalence in higher score groups (8.3% vs. 9.5% vs. 26.3%, P=0.018). After adjusting for age, sex and other relevant comorbidity, SYNTAX score remained a predictor of severe atherosclerosis [adjusted OR 1.63, 95% CI: 1.01-2.62, P=0.046 (per 10 point increase); adjusted OR 5.20, 95% CI: 1.15-23.5, P=0.032 (high vs. low score)].

Conclusions

SYNTAX score was associated with the severity of atherosclerosis in the ascending aorta. Patients with high scores have a 5 times higher chance of severe disease compared to patients with low scores and should warrant preoperative and intraoperative comprehensive assessment of the ascending aorta.

Tin-filtered low-dose chest CT to quantify macroscopic calcification burden of the thoracic aorta

OBJECTIVES

To compare a low-dose, tin-filtered, nonenhanced, high-pitch Sn100 kVp CT protocol (Sn100) with a standard protocol (STP) for the detection of calcifications in the ascending aorta in patients scheduled for cardiac surgery.

METHODS

Institutional Review Board approval for this retrospective study was waived and the study was HIPAA-compliant. The study included 192 patients (128 men; age 68.8 ± 9.9 years), of whom 87 received the STP and 105 the Sn100 protocol. Size-specific dose estimates (SSDE) and radiation doses were obtained using dose monitoring software. Two blinded readers evaluated image quality on a scale from 1 (low) to 5 (high) and the extent of calcifications of the ascending aorta on a scale from 0 (none) to 10 (high), subdivided into 12 anatomic segments.

RESULTS

The Sn100 protocol achieved a mean SSDE of only 0.5 ± 0.1 mGy and 0.20 ± 0.04 mSv compared with the mean SSDE of 5.4 ± 2.2 mGy achieved with the STP protocol (p < 0.0001). Calcification burden was associated with age (p < 0.0001), but was independent of protocol with mean calcification scores of 0.48 ± 1.23 (STP) and 0.55 ± 1.25 (Sn100, p = 0.18). Reader agreement was very good (STP κ = 0.87 ± 0.02, Sn100 κ = 0.88 ± 0.01). The STP protocol provided a higher subjective image quality than the Sn100 protocol: STP median 4, interquartile range 4-5, vs. SN100 3, 3-4; p < 0.0001) and a slightly better depiction of calcification (STP 5, 4-5, vs. Sn100 4, 4-5; p < 0.0001).

CONCLUSIONS

The optimized Sn100 protocol achieved a mean SSDE of only 0.5 ± 0.1 mGy while the depiction of calcifications remained good, and there was no systematic difference in calcification burden between the two protocols.

KEY POINTS

• Tin-filtered, low-dose CT can be used to assess aortic calcifications before cardiac surgery • An optimized Sn100 protocol achieved a mean SSDE of only 0.5 ± 0.1 mGy • The depiction of atherosclerosis of the thoracic aorta was similar with both protocols • The depiction of relevant thoracic pathologies before cardiac surgery was similar with both protocols.

Impact of Modified Transesophageal Echocardiography on Mortality and Stroke after Cardiac Surgery: A Large Cohort Study

The aim of this study was to investigate the impact of perioperative screening with modified transesophageal echocardiography (A-View method). We compared, in consecutive patients who underwent cardiac surgery between 2006 and 2014, 30-day mortality and in-hospital stroke incidence, operated either with perioperative modified TEE screening (intervention group) or only with conventional TEE screening (control group). Of the 8,605 study patients, modified TEE was applied in 1,391 patients (16.2%). Patients in the intervention group were on average older (71 versus 68 years, p < 0.001) and more often females (31.0% versus 28.0%, p < 0.001) and had a higher predicted mortality (EuroSCORE I: 5.9% versus 4.0%, p < 0.001). The observed 30-day mortality was 2.2% and 2.5% in both groups, respectively, with multivariable and propensity-score adjusted relative risks (RRs) of 0.70 (95% CI: 0.50–1.00, p = 0.05) and 0.67 (95% CI: 0.45–0.98, p = 0.04). In-hospital stroke was 2.9% and 2.1% in both groups, respectively, with adjusted RRs of 1.03 (95% CI: 0.73–1.45) and 1.01 (95% CI: 0.71–1.43). In patients undergoing cardiac surgery, use of perioperative screening for aortic atherosclerosis with modified TEE was associated with lower postoperative mortality, but not stroke, as compared to patients operated on without such screening.

Diagnostic accuracy of chest X-ray dose-equivalent CT for assessing calcified atherosclerotic burden of the thoracic aorta

OBJECTIVE

To determine the value of ultralow-dose chest CT for estimating the calcified atherosclerotic burden of the thoracic aorta using tin-filter CT and compare its diagnostic accuracy with chest direct radiography.

METHODS

A total of 106 patients from a prospective, IRB-approved single-centre study were included and underwent standard dose chest CT (1.7 ± 0.7 mSv) by clinical indication followed by ultralow-dose CT with 100 kV and spectral shaping by a tin filter (0.13 ± 0.01 mSv) to achieve chest X-ray equivalent dose in the same session. Two independent radiologists reviewed the CT images, rated image quality and estimated presence and extent of calcification of aortic valve, ascending aorta and aortic arch. Conventional radiographs were also reviewed for presence of aortic calcifications.

RESULTS

The sensitivity of ultralow-dose CT for the detection of calcifications of the aortic valve, ascending aorta and aortic arch was 93.5, 96.2 and 96.2%, respectively, compared with standard dose CT. The sensitivity for the detection of thoracic aortic calcification was significantly lower on chest X-ray (52.3%) compared with ultralow-dose CT (p < 0.001).

CONCLUSION

A reliable estimation of calcified atherosclerotic burden of the thoracic aorta can be achieved with modern tin-filter CT at dose values comparable to chest direct radiography. Advances in knowledge: Our findings suggest that ultralow-dose CT is an excellent tool for assessing the calcified atherosclerotic burden of the thoracic aorta with higher diagnostic accuracy than conventional chest radiography and importantly without the additional cost of increased radiation dose.