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

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.

Postoperative stroke assessment inconsistencies in cardiac surgery: Contributors to higher stroke-related mortality?

OBJECTIVES

In-hospital stroke mortality is surprisingly much worse than for strokes occurring outside of the hospital. Cardiac surgery patients are amongst the highest risk groups for in-hospital stroke and experience high stroke-related mortality. Variability in institutional practices appears to play an important role in the diagnosis, management, and outcome of postoperative stroke. We therefore tested the hypothesis that variability in postoperative stroke management of cardiac surgical patients exists across institutions.

MATERIALS AND METHODS

A 13 item survey was employed to determine postoperative stroke practice patterns for cardiac surgical patients across 45 academic institutions.

RESULTS

Less than half (44%) reported any formal clinical effort to preoperatively identify patients at high risk for postoperative stroke. Epiaortic ultrasonography for the detection of aortic atheroma, a proven preventative measure, was routinely practiced in only 16% of institutions. Forty-four percent (44%) reported not knowing whether a validated stroke assessment tool was utilized for the detection of postoperative stroke, and 20% reported that validated tools were not routinely used. All responders, however, confirmed the availability of stroke intervention teams.

CONCLUSIONS

Adoption of a best practices approach to the management of postoperative stroke is highly variable and may improve outcomes in postoperative stroke after cardiac surgery.

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.

Effects of Bunao-Fuyuan decoction serum on proliferation and migration of vascular smooth muscle cells in atherosclerotic

Atherosclerosis (AS) is a chronic inflammatory disease, the main causes of which include abnormal lipid metabolism, endothelial injury, physical and chemical injury, hemodynamic injury, genetic factors and so on. These causes can lead to inflammatory injury of blood vessels and local dysfunction. Bunao-Fuyuan decoction (BNFY) is a traditional Chinese medicine compound that can treat cardiovascular and cerebrovascular diseases, but its effect on AS is still unknown. The aim of this study was to investigate the effect and mechanism of BNFY in proliferation and migration of vascular smooth muscle cells (VSMCs) on AS. At first, the expression of α-SMA protein in ox-LDL-induced VSMCs, which was detected by immunofluorescence staining and western blot. CCK-8 technique and cloning technique were used to detect the cell proliferation of ox-LDL-induced VSMCs after adding BNFY. Meanwhile, the expression of proliferating protein Ki67 was detected by immunofluorescence staining. Western blot was also used to detect the expression of proliferation-related proteins CDK2, CyclinE1 and P27. Flow cytometry was used to detect the effect of BNFY on cell cycle. The effects of BNFY on proliferation and migration of cells were detected by cell scratch test and Transwell. Western blot was used to detect the expression of adhesion factors ICAM1, VCAM1, muc1, VE-cadherin and RHOA/ROCK-related proteins in cells. We found that the expression of AS marker α-SMA protein increased significantly and cells shriveled and a few floated on the medium after induction of ox-LDL on VSCMs. The proliferation rate of ox-LDL VSMCs decreased significantly after adding different doses of BNFY, and BNFY can inhibit cell cycle. Meanwhile, we also found that cell invasion and migration rate were significantly inhibited and related cell adhesion factors ICAM1, VCAM1, muc1 and VE-cadherin were inhibited too by BNFY. Finally, we found that BNFY inhibited the expression of RHOA, ROCK1, ROCK2, p-MLC proteins in the RHOA/ROCK signaling pathway. Therefore, we can summarize that BNFY may inhibit the proliferation and migration of atherosclerotic vascular smooth muscle cells by inhibiting the activity of RHOA/ROCK signaling pathway.

Timing of Recognition for Perioperative Strokes Following Cardiac Surgery

INTRODUCTION

More than half of reported perioperative strokes following cardiac surgery are identified beyond postoperative day one. The objective of our study was to determine preoperative and intraoperative factors that are associated with stroke following cardiac surgery and to identify factors that may contribute delayed recognition of perioperative stroke.

METHODS

Patients undergoing coronary artery bypass surgery or isolated valve surgery from January 2, 2015 to April 28, 2017 at an academic health system were identified from the Society of Thoracic Surgeons Registry. We determined preoperative and intraoperative factors associated with perioperative stroke. Two neurologists performed retrospective chart reviews on perioperative stroke patients to determine the last seen well time and the stroke cause.

RESULTS

During the study period, 2795 patients underwent coronary artery bypass surgery or isolated valve surgery (mean age 64 ± 11 years, 71% male, 72% Caucasian, 9% history of stroke), of which 43 (1.5%) had a perioperative stroke; 31 (72%) patients had an embolic mechanism of stroke based on neuroimaging. In multivariable analysis, perioperative strokes were independently associated with increasing age (OR 1.04, 95% 1.01-1.07), history of stroke (OR 2.73, 95% CI 1.47-5.06), and history of thoracic aorta disease (OR 3.36, 95% CI 1.16-9.71). Strokes were identified after postoperative day one in 32 (74%) patients of which 26 (81%) had a preoperative last seen well time.

CONCLUSION

Given the high frequency of preoperative last seen well time in perioperative stroke patients who are identified after postoperative day one, delayed stroke recognition may contribute to the bimodal distribution in timing of perioperative stroke. Frequent neurological monitoring within 24 hours after CABG or isolated valve surgery should be considered for all patients undergoing cardiac surgery, particularly elderly patients and those with a history of stroke or thoracic aorta disease, to improve early stroke recognition.

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.