Subtle aortic dissection in a patient with severe aortic regurgitation and undiagnosed bicuspid aortic valve: A case report with a literature review.

BACKGROUND AND AIM OF THE STUDY: A subtle aortic dissection can be challenging to detect despite the availability of multiple diagnostic modalities. Whilst rare, the inability to detect this variant of aortic dissection can lead to a dismal prognosis. We present an extremely rare case of a subtle aortic dissection with supra-annular aortic root intimal tear and acute severe aortic regurgitation in a patient with a bicuspid aortic valve. METHODS: Case report and literature review conserning subtle aortic dissection is provided. RESULTS: Initial concerns were either aortic dissection or infective endocarditis. Despite advanced multimodality preoperative imaging, diagnosis was made intraoperatively and a Bentall procedure with a mechanical aortic valve was performed. CONCLUSIONS: Our case along with the review of current literature emphasizes that current imaging techniques may be inadequate for diagnosis of this rare variant of aortic dissection.

Organ dysfunction in patients with left ventricular impairment: what is the effect of cardiopulmonary bypass?

OBJECTIVE: We have previously demonstrated that avoidance of cardiopulmonary bypass may reduce early mortality and cardiac related complications in patients with left ventricular dysfunction. This study examines the impact of cardiopulmonary bypass in the same subgroup in terms of organ dysfunction and non-cardiac related complications METHODS: A systematic literature review identified 24 studies including 7,976 patients. Data was extracted for the following outcomes of interest: stroke, renal failure, ventilation time, pulmonary complications and sternal wound infection. Random effects meta-analysis was used to aggregate the data. Sensitivity and heterogeneity were assessed. RESULTS: Meta-analysis through subgroup analysis of the highest quality studies revealed that the off-pump technique is associated with significantly lower incidence of stroke, renal failure, ventilation time and sternal wound infection. CONCLUSION: These results highlight an important link between cardiopulmonary bypass and the incidence of multi-organ dysfunction in patients with left ventricular dysfunction. The results add to the growing body of evidence that off-pump surgery is more beneficial in high-risk patients. Even in the light of mixed reports on graft patency and completeness of revascularisation, the technique may be justified in selected patients in attempt to reduce organ dysfunction.

The genetic basis of thoracic aortic disease: The future of aneurysm classification?

The expansion in the repertoire of genes linked to thoracic aortic aneurysms (TAA) has revolutionised our understanding of the disease process. The clinical benefits of such progress are numerous, particularly helping our understanding of non-syndromic hereditary causes of TAA (HTAAD) and further refinement in the subclassification of disease. Furthermore, the understanding of aortic biomechanics and mechanical homeostasis has been significantly informed by the discovery of deleterious mutations and their effect on aortic phenotype. The drawbacks in genetic testing in TAA lie with the inability to translate genotype to accurate prognostication in the risk of thoracic aortic dissection (TAD), which is a life-threatening condition. Under current guidelines, there are no metrics by which those at risk for dissection with normal aortic diameters may undergo preventive surgery. Future research lies with more advanced genetic diagnosis of HTAAD and investigation of the diverse pathways involved in its pathophysiology, which will i) serve to improve our understanding of the underlying mechanisms, ii) improve guidelines for treatment and iii) prevent complications for HTAAD and sporadic aortopathies.

Mid-term outcomes of aortic valve repair using an anatomically shaped internal annuloplasty ring.

OBJECTIVES: The Hemispherical Aortic Annuloplasty Reconstructive Technology (HAART) ring is a rigid, internal and geometric device. The objective of this article is to assess the mid-term outcomes of aortic valve repair (AVr) using this prosthesis. METHODS: A prospectively maintained database was used to obtain outcomes for adult patients undergoing AVr using the HAART ring between September 2017 and June 2023. All aortic patients at our institution undergo life-long surveillance with regular assessment and valve imaging. RESULTS: Seventy-one patients underwent AVr using the HAART device: 53 had a trileaflet valve and 18 a bicuspid valve. The median age was 54 years, and most were male (79%). Many required concomitant intervention: 46% had a root procedure and 77% an arch repair. There were no in-hospital deaths, and the median postoperative stay was 5 days. At a mean follow-up of 3.9 (±1.1) years, freedom from reoperation was 94%. Late imaging demonstrated: zero trace (25%), 1+ (54%), 2+ (15%) and 4+ (6%) aortic insufficiency (AI). Eleven patients have ≥moderate AI under surveillance, all of whom have a trileaflet valve (21% of trileaflet patients). Four patients required reoperation: 3 for ring dehiscence and 1 for endocarditis. CONCLUSIONS: Although early results using the HAART device are encouraging, mid-term results raise concern as 21% of trileaflet patients developed recurrent ≥moderate AI by 4 years post-repair. We experienced 3 incidences of ring dehiscence requiring reoperation. Based on this, we recommend caution using the sub-annular approach for stabilization in patients with trileaflet aortic valves. Long-term results are needed to assess outcomes against established techniques.

Geometry and flow in ascending aortic aneurysms are influenced by left ventricular outflow tract orientation: Detecting increased wall shear stress on the outer curve of proximal aortic aneurysms.

BACKGROUND: The geometrical characterization of ascending thoracic aortic aneurysms in clinical practice is limited to diameter measurements. Despite growing interest in hemodynamic assessment, its relationship with ascending thoracic aortic aneurysm pathogenesis is poorly understood. This study examines the relationship between geometry of the ventriculo-aortic junction and blood flow patterns in ascending thoracic aortic aneurysm disease. METHODS: Thirty-three patients with ascending thoracic aortic aneurysms (exclusions: bicuspid aortic valves, connective tissue disease) underwent 4-dimensional flow magnetic resonance imaging. After image segmentation, geometrical parameters were measured, including aortic curvature, tortuosity, length, and diameter. A unique angular measurement made by the trajectory of the left ventricular outflow tract axis and the proximal aorta was also conducted. Velocity profiles were quantitatively and qualitatively analyzed. In addition, 11 patients (33%) underwent wall shear stress mapping of the ascending thoracic aortic aneurysm region using computational fluid dynamics simulation. RESULTS: Greater left ventricular outflow tract aortic angles were associated with larger aortic diameters at the levels of the sinus (coefficient = 0.387, P = .014) and ascending aorta (coefficient = 0.284, P = .031). Patients with left ventricular outflow tract aortic angles greater than 60° had marked asymmetric flow acceleration on the outer curvature in the proximal aorta, ascertained from 4-dimensional flow analysis. For patients undergoing computational fluid dynamics assessment, regression analysis found that higher left ventricular outflow tract aortic angles were associated with significantly higher wall shear stress values in the outer curve of the aorta (coefficient 0.07, 95% confidence interval 0.04-0.11, P = .002): Angles greater than 50° yielded time-averaged wall shear stress values greater than 2.5 Pa, exhibiting a linear relationship. CONCLUSIONS: Our findings strengthen the hypothesis of flow-mediated ascending thoracic aortic aneurysm disease progression and that left ventricular outflow tract aortic angle may be a predictor of disease severity.

Thoracoscopic esophagectomy in the prone position.

BACKGROUND: Minimally invasive esophageal surgery has arisen in an attempt to reduce the significant complications associated with esophagectomy. Despite proposed technical and physiological advantages, the prone position technique has not been widely adopted. This article reviews the current status of prone thoracoscopic esophagectomy. METHODS: A systematic literature search was performed to identify all published clinical studies related to prone esophagectomy. Medline, EMBASE and Google Scholar were searched using the keywords "prone," "thoracoscopic," and "esophagectomy" to identify articles published between January 1994 and September 2010. A critical review of these studies is given, and where appropriate the technique is compared to the more traditional minimally invasive technique utilising the left lateral decubitus position. RESULTS: Twelve articles reporting the outcomes following prone thoracoscopic oesophagectomy were tabulated. These studies were all non-randomised single-centre prospective or retrospective studies of which four compared the technique to traditional minimally invasive surgery. Although prone esophagectomy is demonstrated as being both feasible and safe, there is no convincing evidence that it is superior to other forms of esophageal surgery. Most authors comment that the prone position is associated with superior surgical ergonomics and theoretically offers a number of physiological benefits. CONCLUSION: The ideal approach within minimally invasive esophageal surgery continues to be a subject of debate since no single method has produced outstanding results. Further clinical studies are required to see whether ergonomic advantages of the prone position can be translated into improved patient outcomes.

Determining the genetic contribution in patients with non-syndromic ascending thoracic aortic aneurysms: Correlation with findings from computational pathology.

OBJECTIVES: This study aims to identify the clinical utility of targeted-genetic sequencing in a cohort of patients with TAA and establish a new method for regional histological characterisation of TAA disease. METHODS: Fifty-four patients undergoing surgery for proximal TAA were recruited. EXCLUSIONS: connective tissue disease, bicuspid aortic valves, redo surgery. All patients underwent next generation sequencing (NGS) using a custom gene panel containing 63 genes previously associated with TAA on Illumina MiSeqor NextSeq550 platforms. Explanted TAA tissue was obtained en-bloc from 34/54 patients, and complete circumferential strips of TAA tissue processed into whole slides which were subsequently digitalised. Computational pathology methods were employed to quantify elastin, cellularity and collagen in six equally divided regions across the whole aneurysm circumference. RESULTS: Of 54 patients, clearly pathogenic or potentially pathogenic variants were found in 7.4%: namely LOX, PRKG1, TGFBR1 and SMAD3 genes. 55% had at least one variant of unknown significance (VUS) and seven of the VUSs were in genes with a strong disease association (category A) genes, whilst 15 were from moderate risk (category B) genes. Elastin and collagen abundance displayed high regional variation throughout the aneurysm circumference. In patients with <60% total elastin, the loss of elastin was more significant on the outer curve (38.0% vs 47.4%, p = 0.0094). The presence of VUS, higher pulse wave velocity and advancing age were predictors of elastin loss (regression analysis: p < 0.05). CONCLUSIONS: These findings demonstrate the heterogeneity of TAA disease microstructure and the potential link between histological appearance and clinical factors, including genetic variation.

High Wall Shear Stress can Predict Wall Degradation in Ascending Aortic Aneurysms: An Integrated Biomechanics Study.

Background: Blood flow patterns can alter material properties of ascending thoracic aortic aneurysms (ATAA) via vascular wall remodeling. This study examines the relationship between wall shear stress (WSS) obtained from image-based computational modelling with tissue-derived mechanical and microstructural properties of the ATAA wall using segmental analysis. Methods: Ten patients undergoing surgery for ATAA were recruited. Exclusions: bicuspid aortopathy, connective tissue disease. All patients had pre-operative 4-dimensional flow magnetic resonance imaging (4D-MRI), allowing for patient-specific computational fluid dynamics (CFD) analysis and anatomically precise WSS mapping of ATAA regions (6-12 segments per patient). ATAA samples were obtained from surgery and subjected to region-specific tensile and peel testing (matched to WSS segments). Computational pathology was used to characterize elastin/collagen abundance and smooth muscle cell (SMC) count. Results: Elevated values of WSS were predictive of: reduced wall thickness [coef -0.0489, 95% CI (-0.0905, -0.00727), p = 0.022] and dissection energy function (longitudinal) [-15,0, 95% CI (-33.00, -2.98), p = 0.048]. High WSS values also predicted higher ultimate tensile strength [coef 0.136, 95% CI (0 0.001, 0.270), p = 0.048]. Additionally, elevated WSS also predicted a reduction in elastin levels [coef -0.276, 95% (CI -0.531, -0.020), p = 0.035] and lower SMC count ([oef -6.19, 95% CI (-11.41, -0.98), p = 0.021]. WSS was found to have no effect on collagen abundance or circumferential mechanical properties. Conclusions: Our study suggests an association between elevated WSS values and aortic wall degradation in ATAA disease. Further studies might help identify threshold values to predict acute aortic events.

Challenges and satisfaction in Cardiothoracic Surgery Residency Programmes: insights from a Europe-wide survey.

OBJECTIVES: The increasing complexity of surgical patients and working time constraints represent challenges for training. In this study, the European Association for Cardio-Thoracic Surgery Residents' Committee aimed to evaluate satisfaction with current training programmes across Europe. METHODS: We conducted an online survey between October 2018 and April 2019, completed by a total of 219 participants from 24 countries. RESULTS: The average respondent was in the fourth or fifth year of training, mostly on a cardiac surgery pathway. Most trainees follow a 5-6-year programme, with a compulsory final certification exam, but no regular skills evaluation. Only a minority are expected to take the examination by the European Board of Cardiothoracic Surgery. Participants work on average 61.0 ± 13.1 h per week, including 27.1 ± 20.2 on-call. In total, only 19.7% confirmed the implementation of the European Working Time Directive, with 42.0% being unaware that European regulations existed. Having designated time for research was reported by 13.0%, despite 47.0% having a postgraduate degree. On average, respondents rated their satisfaction 7.9 out of 10, although 56.2% of participants were not satisfied with their training opportunities. We found an association between trainee satisfaction and regular skills evaluation, first operator experience and protected research time. CONCLUSIONS: On average, residents are satisfied with their training, despite significant disparities in the quality and structure of cardiothoracic surgery training across Europe. Areas for potential improvement include increasing structured feedback, research time integration and better working hours compliance. The development of European guidelines on training standards may support this.

The risk of misdiagnosis in acute thoracic aortic dissection: a review of current guidelines.

Acute aortic syndrome and in particular aortic dissection (AAD) persists as a cause of significant morbidity and mortality despite improvements in surgical management. This clinical review aims to explore the risks of misdiagnosis, outcomes associated with misdiagnosis and evaluate current diagnostic methods for reducing its incidence.Due to the nature of the pathology, misdiagnosing the condition and delaying management can dramatically worsen patient outcomes. Several diagnostic challenges exist, including low prevalence, rapidly propagating pathology, non-discrete symptomatology, non-specific signs, analogy with other acute conditions and lack of management infrastructure. A similarity to acute coronary syndromes is a specific concern and risks patient maltreatment. AAD with malperfusion syndromes are both a cause of misdiagnosis and marker of disease complication, requiring specifically tailored management plans from the emergency setting.Despite improvements in diagnostic measures, including imaging modalities and biomarkers, misdiagnosis of AAD remains commonplace and current guidelines are relatively limited in preventing its occurrence. This paper recommends the early use of AAD risk scoring, focused echocardiography and most importantly, fast-tracking patients to cross-sectional imaging where the suspicion of AAD is high. This has the potential to improve the diagnostic process for AAD and limit the risk of misdiagnosis. However, our understanding remains limited by the lack of large patient datasets and an adequately audited processes of emergency department practice.

Phase-contrast magnetic resonance imaging and computational fluid dynamics assessment of thoracic aorta blood flow: a literature review.

The death rate from thoracic aortic disease is on the rise and represents a growing global health concern as patients are often asymptomatic before acute events, which have devastating effects on health-related quality of life. Biomechanical factors have been found to play a major role in the development of both acquired and congenital aortic diseases. However, much is still unknown and translational benefits of this knowledge are yet to be seen. Phase-contrast cardiovascular magnetic resonance imaging of thoracic aortic blood flow has emerged as an exceptionally powerful non-invasive tool enabling visualization of complex flow patterns, and calculation of variables such as wall shear stress. This has led to multiple new findings in the areas of phenotype-dependent bicuspid valve flow patterns, thoracic aortic aneurysm formation and aortic prosthesis performance assessment. Phase-contrast cardiovascular magnetic resonance imaging has also been used in conjunction with computational fluid modelling techniques to produce even more sophisticated analyses, by allowing the calculation of haemodynamic variables with exceptional temporal and spatial resolution. Translationally, these technologies may potentially play a major role in the emergence of precision medicine and patient-specific treatments in patients with aortic disease. This clinically focused review will provide a systematic overview of key insights from published studies to date.

Can activity monitors predict outcomes in patients with heart failure? A systematic review.

Actigraphy is increasingly incorporated into clinical practice to monitor intervention effectiveness and patient health in congestive heart failure (CHF). We explored the prognostic impact of actigraphy-quantified physical activity (AQPA) on CHF outcomes. PubMed and Medline databases were systematically searched for cross-sectional studies, cohort studies or randomised controlled trials from January 2007 to December 2017. We included studies that used validated actigraphs to predict outcomes in adult HF patients. Study selection and data extraction were performed by two independent reviewers. A total of 17 studies (15 cohort, 1 cross-sectional, 1 randomised controlled trial) were included, reporting on 2,759 CHF patients (22-89 years, 27.7% female). Overall, AQPA showed a strong inverse relationship with mortality and predictive utility when combined with established risk scores, and prognostic roles in morbidity, predicting cognitive function, New York Heart Association functional class and intercurrent events (e.g. hospitalisation), but weak relationships with health-related quality of life scores. Studies lacked consensus regarding device choice, time points and thresholds of PA measurement, which rendered quantitative comparisons between studies difficult. AQPA has a strong prognostic role in CHF. Multiple sampling time points would allow calculation of AQPA changes for incorporation into risk models. Consensus is needed regarding device choice and AQPA thresholds, while data management strategies are required to fully utilise generated data. Big data and machine learning strategies will potentially yield better predictive value of AQPA in CHF patients.

Single stage repair for aortic root aneurysm in a patient with coexisting coarctation incorporating the Cabrol technique: a case report.

BACKGROUND: A 44 year old man who presented with a history of chest pain and dyspnoea was found to have an aneurysm of the aortic root, aortic valve insufficiency, and coarctation of the aorta. CASE PRESENTATION: The patient underwent a single stage procedure to treat the aortic root, valve and coarctation with a composite valved conduit and extra-anatomic bypass of the coarctation. The modified Cabrol technique was necessary to attach the coronary buttons due to grossly abnormal anatomy. The patient made a remarkable recovery and was discharged on the 8th post-operative day. CONCLUSION: This case report highlights the feasibility and efficacy of performing a single stage procedure on complex coarctation with associated cardiac defects. To the best of our knowledge, this is the first report of the modified Cabrol technique being used in this particular setting.

Vivien Theodore Thomas (1910-1985): An African-American laboratory technician who went on to become an innovator in cardiac surgery.

Vivien Theodore Thomas (1910-1985) was an African-American laboratory technician and instructor of surgery at Johns Hopkins University, Baltimore. He was born as the grandson of a slave in Lousiana, working as a carpenter and subsequently as a laboratory technician after the great depression and the loss of his savings derailed his plans to become a doctor. In his role as a laboratory technician, he overcame challenging personal circumstances to become an innovator in paediatric cardiac surgery, despite having no formal college education. He played an important role in assisting Alfred Blalock and Helen Taussig in the development of the 'Blalock-Taussig' shunt, a procedure used to improve the survival of children with cyanotic congenital heart defects. He also contributed to major breakthroughs in research covering a spectrum of disorders such as traumatic shock, coarctation of the aorta and transposition of the great arteries. He acted as a teacher and mentor to a generation of surgical residents and technicians who went on to become leaders in their field across the USA. A television film based on his life was premiered by HBO in 2004 titled 'Something the Lord made'.

Quality of life after mitral valve intervention.

Advancements in surgical technique and understanding of the pathophysiology of mitral valve (MV) dysfunction have led to improved outcomes. Seen as a development beyond measures of morbidity and mortality, health-related quality-of-life (HRQOL) outcome measures are becoming increasingly popular. These measures are important because complications following routine (i.e. low-risk) operations on the MV are uncommon and further markers of outcome are needed. Surgeons are increasingly operating earlier on asymptomatic patients and will need to prove that HRQOL is not impacted. Novel minimally invasive and transcatheter technologies will also need to demonstrate satisfactory HRQOL outcomes prior to widespread use. This systematic review provides an overview of all available literature detailing HRQOL in patients receiving MV interventions. In the 43 studies included, 6865 patients underwent procedures ranging from open replacement to percutaneous repair using devices such as the Mitraclip Clip Delivery System (MitraClip) (Abbott Vascular, Santa Clara, CA, USA). Most studies performed baseline HRQOL assessment, allowing postinterventional comparison. While the underlying literature had deficiencies, most studies report acceptable postintervention HRQOL that was comparable to that of matched general populations. Patient-specific (e.g. female gender, renal dysfunction) and surgical-specific factors (e.g. replacement instead of repair, elevated transmitral gradient) were identified that predispose patients to poorer long-term HRQOL outcomes. These factors are important for clinicians developing strategies to maximize their HRQOL outcomes. Future randomized studies would benefit from HRQOL measurements at specific time points to allow large-scale comparisons. Establishing a common HRQOL instrument for use in MV intervention studies may support detailed comparisons between specific techniques. Physical activity monitors, physiological biomarkers and radiological markers could also be used as innovative indicators of functional outcome.

Frozen elephant trunk reconstruction for right-sided aortic arch with aberrant left subclavian artery and aneurysm of the descending aorta: a case report.

BACKGROUND: A 59-year old man being investigated for back pain was found to have aneurysmal dilatation of a right-sided aortic arch and descending thoracic aorta together with an aberrant left subclavian artery. CASE PRESENTATION: He underwent repair of this utilising the frozen elephant trunk technique, which dealt with all three pathologies in one-stage. He made an unremarkable recovery and was discharged home on the 8th post-operative day. CONCLUSIONS: This case report further demonstrates the flexibility and safety of the frozen elephant trunk in dealing with complex aortic pathology as a single-stage procedure.

A review of the surgical management of right-sided aortic arch aneurysms.

Aneurysms and dissections of the right-sided aortic arch are rare and published data are limited to a few case reports and small series. The optimal treatment strategy of this entity and the challenges associated with their management are not yet fully investigated and conclusive. We performed a systematic review of the literature to identify all patients who underwent surgical or endovascular intervention for right aortic arch aneurysms or dissections. The search was limited to the articles published only in English. We focused on presentation and critically assessed different management strategies and outcomes. We identified 74 studies that reported 99 patients undergoing surgical or endovascular intervention for a right aortic arch aneurysm or dissection. The median age was 61 years. The commonest presenting symptoms were chest or back pain and dysphagia. Eighty-eight patients had an aberrant left subclavian artery with only 11 patients having the mirror image variant of a right aortic arch. The commonest pathology was aneurysm arising from a Kommerell's diverticulum occurring in over 50% of the patients. Twenty-eight patients had dissections, 19 of these were Type B and 9 were Type A. Eighty-one patients had elective operations while 18 had emergency procedures. Sixty-seven patients underwent surgical treatment, 20 patients had hybrid surgical and endovascular procedures and 12 had totally endovascular procedure. There were 5 deaths, 4 of which were in patients undergoing emergency surgery and none in the endovascular repair group. Aneurysms and dissections of a right-sided aortic arch are rare. Advances in endovascular treatment and hybrid surgical and endovascular management are making this rare pathology amenable to these approaches and may confer improved outcomes compared with conventional extensive repair techniques.

Quality of life after intervention on the thoracic aorta.

Surgery on the thoracic aorta is challenging and historically associated with significant mortality and morbidity. In recent times, there has been increased emphasis on the importance of health-related quality of life (HRQOL) measures. It is seen as a development beyond isolated markers of outcome such as operative mortality and is particularly applicable to aortic surgery given the number of asymptomatic patients operated on (for prognostic grounds), and rapidly advancing endovascular technologies which require proper assessment. This systematic review provides an outline of all available literature detailing HRQOL in patients receiving intervention (both open and endovascular) on the thoracic aorta. In total, 30 studies were identified encompassing 4746 patients undergoing a variety of procedures from aortic root replacement to thoracoabdominal aortic aneurysm repair. While there were deficiencies in the underlying literature such as lack of baseline HRQOL assessment, the majority of the studies confirm that HRQOL after major aortic surgery (including on the elderly and in emergency situations) is acceptable and compares well to matched general populations. Strategies for improving the HRQOL in aortic surgery are summarized and include the need for surgeons to plan cerebral protection methods more carefully and to develop operative strategies to avoid reoperation or reintervention, as this is associated with deterioration of long-term HRQOL. Randomized studies measuring baseline and follow-up HRQOL at specific set points are needed. Innovative research methods could be employed in future studies with the aim of correlating HRQOL with imaging or physiological/inflammation biomarkers, or other end points such as aortic stiffness or wall shear stress to characterize disease progression and prognosis.