Guilt by association: a paradigm for detection of silent aortic disease

Association of simple renal cysts to aneurysm sac shrinkage in true thoracic aortic aneurysms after thoracic endovascular aortic repair

BACKGROUND

An increased prevalence of thoracic aortic aneurysms (TAA) has been demonstrated in patients with simple renal cysts (SRC); patients with SRC have a less elastic aortic wall than those without SRC. The purpose of this study was to evaluate aneurysm sac shrinkage after thoracic endovascular aortic repair (TEVAR) for true TAA in patients with and without SRC.

METHODS

One hundred three patients with true aneurysms of the thoracic aorta who underwent TEVAR at our university hospital from November 2013 to December 2021 were included in this study. Aneurysm sac size was compared between that on baseline preoperative computed tomography and that on postoperative computed tomography scans at 1 year. A change in aneurysm sac size ≥5 mm was considered to be significant, whether due to expansion or shrinkage.

RESULTS

The patients were divided into two groups: those with SRC (46 patients [45%]) and those without SRC (57 patients [55%]). At 1 year, there was a significant difference in the proportion of aneurysm sac shrinkage between patients with SRC and those without SRC (23.9% vs 59.6%; P < .001). Patients with SRC showed significantly less aneurysm sac shrinkage than those without SRC (-1.8 ± 5.6 mm vs -5.1 ± 6.6 mm; P = .009). Univariable and multivariable analyses showed that the initial sac diameter (odds ratio, 1.08; 95% confidence interval, 1.03-1.14; P = .002) and the presence of SRC (odds ratio, 0.15; 95% confidence interval, 0.06-0.40; P < .001) were positively and negatively associated with aneurysm sac shrinkage after TEVAR, respectively.

CONCLUSIONS

The presence of a SRC was independently associated with failure of aneurysm sac shrinkage after TEVAR for true TAA. This suggests that the presence of a SRC may be a predictor for the failure of aneurysm sac shrinkage after TEVAR.

The natural history of aortic root aneurysms

The aortic root has a different embryologic origin from all other segments of the human aorta, a feature that likely confers unique susceptibilities, anatomical patterns, and clinical behavior of aneurysm disease in this vital location. In this manuscript, we review the natural history of ascending aortic aneurysm, with a specific focus on the aortic root. The specific central message is that root dilatation is more malignant than ascending dilatation.

Aortic arch surgery for type B aortic dissection: How far should we go? The value of a hybrid approach

Traditionally, the management of type B aortic dissection has been the domain of the vascular surgeons. Timing and type of intervention still generate debate. We sought to review our early experience with the treatment of this condition based on a hybrid approach following an aortic multi-disciplinary team meeting involving close cooperation between cardiac surgeons, vascular surgeons, interventional radiologists, vascular anesthetists, and cardiac anesthetists. Four patients (age 41-56 years; 3 males; 1 female) with type B aortic dissection underwent aortic arch surgery through a hybrid approach: one elective procedure consisting of ascending aorta and hemi-arch replacement with debranching followed by thoracic endovascular aortic repair (TEVAR); one redo procedure requiring aortic arch replacement with hybrid frozen elephant trunk; two acute presentations (aortic arch replacement and debranching followed by TEVAR; AVR with ascending aorta, arch, and proximal descending thoracic aorta replacement with conventional elephant trunk and debranching). Deep hypothermic circulatory arrest was required in three patients. Despite respiratory complications and slightly prolonged postoperative course, all patients survived without onset of stroke, paraplegia, malperfusion, endoleak, or need for re-exploration. Follow-up remains satisfactory. Different factors may affect outcome following complex aortic procedures. Nevertheless, close cooperation between cardiac surgeons, vascular surgeons, and interventional radiologists may reduce potential for complications and address aspects that may not be completely within the domain of individual specialists.

Existing and Emerging Approaches to Risk Assessment in Patients with Ascending Thoracic Aortic Dilatation

Ascending thoracic aortic aneurysm is a life-threatening disease, which is difficult to detect prior to the occurrence of a catastrophe. Epidemiology patterns of ascending thoracic aortic dilations/aneurysms remain understudied, whereas the risk assessment of it may be improved. The electronic databases PubMed/Medline 1966–2022, Web of Science 1975–2022, Scopus 1975–2022, and RSCI 1994–2022 were searched. The current guidelines recommend a purely aortic diameter-based assessment of the thoracic aortic aneurysm risk, but over 80% of the ascending aorta dissections occur at a size that is lower than the recommended threshold of 55 mm. Moreover, a 55 mm diameter criterion could exclude a vast majority (up to 99%) of the patients from preventive surgery. The authors review several visualization-based and alternative approaches which are proposed to better predict the risk of dissection in patients with borderline dilated thoracic aorta. The imaging-based assessments of the biomechanical aortic properties, the Young’s elastic modulus, the Windkessel function, compliance, distensibility, wall shear stress, pulse wave velocity, and some other parameters have been proposed to improve the risk assessment in patients with ascending thoracic aortic aneurysm. While the authors do not argue for shifting the diameter threshold to the left, they emphasize the need for more personalized solutions that integrate the imaging data with the patient’s genotypes and phenotypes in this heterogeneous pathology.

The Presence of Simple Renal Cysts Is Associated With Increased Arterial Stiffness in Patients With Abdominal Aortic Aneurysm

Simple renal cysts (SRC) are associated with the development of abdominal aortic aneurysms (AAA). We hypothesized that patients with AAA and SRC have increased arterial stiffness (AS) compared with patients without SRC. Patients (n=223) with an infrarenal AAA undergoing pulse wave analysis were recruited. Brachial-ankle pulse wave velocity (PWV) was measured (automated oscillometric method) as an index of AS. Participants were categorized into those with increased AS and those with normal/borderline AS (threshold: 1800 cm/s); 134 patients (60.1%) had increased AS and 89 (39.9%) patients had normal/borderline AS. Multivariable analyses showed that age ≥75 years (odds ratio [OR], 2.83; 95% confidence interval [CI], 1.51-5.72; P=.002), systolic blood pressure ≥140 mmHg (OR, 5.05; 95% CI, 2.35-10.83; P<.001), hypertension (OR, 2.28; 95% CI, 1.08-4.79; P=.030), and presence of SRC (OR, 1.89; 95% CI, 1.03-3.46; P=.040) were independent risk factors for increased AS. The presence of SRC is an independent risk factor for increased AS in patients with an AAA. This association suggests that patients with SRC may have severe aortic wall degeneration and thus the presence of SRC may be pathologically linked to the development of AAA.

An Emergent Nexus between Striae and Thoracic Aortic Dissection

Current approaches to stratify the risk for disease progression in thoracic aortic aneurysm (TAA) lack precision, which hinders clinical decision making. Connective tissue phenotyping of children with TAA previously identified the association between skin striae and increased rate of aortic dilation. The objective of this study was to analyze associations between connective tissue abnormalities and clinical endpoints in adults with aortopathy. Participants with TAA or aortic dissection (TAD) and trileaflet aortic valve were enrolled from 2016 to 2019 in the setting of cardiothoracic surgical care. Data were ascertained by structured interviews with participants. The mean age among 241 cases was 61 ± 13 years. Eighty (33%) had history of TAD. While most participants lacked a formal syndromic diagnosis clinically, connective tissue abnormalities were identified in 113 (47%). This included 20% with abdominal hernia and 13% with skin striae in atypical location. In multivariate analysis, striae and hypertension were significantly associated with TAD. Striae were associated with younger age of TAD or prophylactic aortic surgery. Striae were more frequent in TAD cases than age- and sex-matched controls. Thus, systemic features of connective tissue dysfunction were prevalent in adults with aortopathy. The emerging nexus between striae and aortopathy severity creates opportunities for clinical stratification and basic research.

Root Dilatation Is More Malignant Than Ascending Aortic Dilation

Background

Data from the International Registry of Acute Aortic Dissection indicate that the guideline criterion of 5.5 cm for ascending aortic intervention misses many dissections occurring at smaller dimensions. Furthermore, studies of natural behavior have generally treated the aortic root and the ascending aorta as 1 unit despite embryological, anatomical, and functional differences. This study aims to disentangle the natural histories of the aforementioned aortic segments, allowing natural behavior to define specific intervention criteria for root and ascending segments of the aorta.

Methods and Results

Diameters of the aortic root and mid‐ascending segment were measured separately. Long‐term complications (dissection, rupture, and death) were analyzed retrospectively for 1162 patients with ascending thoracic aortic aneurysm. Cox regression analysis suggested that aortic root dilatation (P=0.017) is more significant in predicting adverse events than mid‐ascending aortic dilatation (P=0.087). Short stature posed as a serious risk factor. The dedicated risk curves for the aortic root and the mid‐ascending aorta revealed hinge points at 5.0 and 5.25 cm, respectively.

Conclusions

The natural histories of the aortic root and mid‐ascending aorta are uniquely different. Dilation of the aortic root imparts a significant higher risk of adverse events. A diameter shift for intervention to 5.0 cm for the aortic root and to 5.25 cm for the mid‐ascending aorta should be considered at expert centers.

Identifying functionally relevant candidate genes for inflexible ethanol intake in mice and humans using a guilt-by-association approach

Gene prioritization approaches are useful tools to explore and select candidate genes in transcriptome studies. Knowing the importance of processes such as neuronal activity, intracellular signal transduction, and synapse plasticity to the development and maintenance of compulsive ethanol drinking, the aim of the present study was to explore and identify functional candidate genes associated with these processes in an animal model of inflexible pattern of ethanol intake. To do this, we applied a guilt-by-association approach, using the GUILDify and ToppGene software, in our previously published microarray data from the prefrontal cortex (PFC) and striatum of inflexible drinker mice. We then tested some of the prioritized genes that showed a tissue-specific pattern in postmortem brain tissue (PFC and nucleus accumbens (NAc)) from humans with alcohol use disorder (AUD). In the mouse brain, we prioritized 44 genes in PFC and 26 in striatum, which showed opposite regulation patterns in PFC and striatum. The most prioritized of them (i.e., Plcb1 and Prkcb in PFC, and Dnm2 and Lrrk2 in striatum) were associated with synaptic neuroplasticity, a neuroadaptation associated with excessive ethanol drinking. The identification of transcription factors among the prioritized genes suggests a crucial role for Irf4 in the pattern of regulation observed between PFC and striatum. Lastly, the differential transcription of IRF4 and LRRK2 in PFC and nucleus accumbens in postmortem brains from AUD compared to control highlights their involvement in compulsive ethanol drinking in humans and mice.

Association of hernia with subsequent aortic aneurysm in geriatric patients

OBJECTIVE

Although inguinal hernia and aortic aneurysm share similar pathogenic mechanisms of collagen and elastin destruction, their clinical association in geriatric patients is inconclusive. We assessed the association between hernia and the subsequent occurrence of aortic aneurysm in geriatric patients.

METHODS

Adult patients with hernias between 2000 and 2012 were identified from a longitudinal claims database of 1 million beneficiaries from Taiwan's National Health Insurance program, and a control group of patients without hernia were matched by propensity score in a ratio of 1:3. Patients previously diagnosed with aortic aneurysms or connective tissue diseases were excluded. Follow-up ended on December 31, 2013. The incidence rate of aortic aneurysm was compared between patients with hernia and those without. Cox proportional hazards models were used to estimate relative hazards.

RESULTS

After propensity score matching, there were 16,933 patients with hernia (aged 20-64 years: 10,326; ≥65 years: 6607) and 50,799 patients without hernia (aged 20-64: 30,978; ≥65: 19,821). Patients with hernia had a greater incidence rate and hazard ratio of aortic aneurysm than did patients without hernia (6.4 vs 4.8/10,000 person-years; adjusted subdistribution hazard ratio [sdHR], 1.34; 95% confidence interval [CI], 1.02-1.76; P = .03), especially for those aged ≥65 years (15.6 vs 10.4/10,000 person-years; adjusted sdHR, 1.44; 95% CI, 1.07-1.94; P = .01) In addition, geriatric patients with hernia were associated with a marginally greater risk of thoracic (adjusted sdHR, 1.66; 95% CI, 0.96-2.86) and abdominal (adjusted sdHR, 1.36; 95% CI, 0.96-1.94) aortic aneurysm rupture.

CONCLUSIONS

Geriatric patients with hernia were associated with a greater incidence of aortic aneurysm than were those without.

Aortic root and ascending aorta dimensions in acute aortic dissection

Objectives:

Aim of this study was to evaluate ascending aorta and aortic root dimension at acute type A dissection (acute aortic dissection) and to identify demographics elements being allied to the acute event.

Methods:

In a period between 2009 and 2017, 225 (n = 71, 32% female, mean age = 63 ± 12 years) patients eligible for analysis of ascending aorta and 223 (n = 70, 31% female, mean age = 63 ± 13 years) of aortic root were included in this study. Aortic diameter was assessed in preoperative computed tomography scan. The predissection diameters were modeled from the diameters obtained at diagnosis, assuming 30% augmentation of the diameter at acute event.

Results:

The mean diameter of the ascending aorta at dissection was 46 ± 8 mm and the modeled diameter was 32.3 ± 5.7 mm. The diameter of the aortic root at dissection was 42 ± 8 mm and modeled diameter was 29.5 ± 5.6 mm. In multivariate analysis, female gender (p = 0.026) and history of cerebrovascular event (p = 0.001) were associated with acute aortic dissection in small aortic root. Patient age (p < 0.001) and history of inguinal hernia (p = 0.001) in ascending aorta <55 mm correlated with acute aortic dissection.

Conclusion:

Modeling indicates that more than 90% of patients had aortic root and ascending aorta diameter <45 mm. It seems that the aortic diameter expansion over the 55 mm in development of acute aortic dissection is overestimated. Parameters other than aortic size were identified, which may be considered when patients at high risk for dissection were identified.

Symptoms Matter: A Symptomatic but Radiographically Elusive Ascending Aortic Dissection

Symptoms attributable to a thoracic aortic aneurysm (TAA) are a separate indication for prophylactic repair, irrespective of aortic size. We present the case of a 56-year-old female with a history of a thoracic ascending aortic aneurysm (TAAA) and four other heart and arch vessel abnormalities who presented to us with chest pain radiating to her back. Computed Tomography and echocardiography showed no evidence of a dissection and revealed a maximal ascending aortic diameter of 4.2 cm. The patient subsequently underwent root-sparing ascending aortic and hemiarch replacement due to her threatening symptomatology. A focal dissection was discovered intraoperatively, resembling a similar case previously reported by our team.

Simple renal cysts and bovine aortic arch: markers for aortic disease

Objective

This study aimed to assess the prevalence of thoracic aortic disease (TAD) and abdominal aortic aneurysms (AAA) among patients with simple renal cyst (SRC) and bovine aortic arch (BAA).

Methods

Through a retrospective search for patients who underwent both chest and abdominal CT imaging at our institution from 2012 to 2016, we identified patients with SRC and BAA and propensity score matched them to those without these features by age, gender and presence of hypertension, hyperlipidaemia, diabetes and chronic kidney disease.

Results

Of a total of 35 498 patients, 6366 were found to have SRC. Compared with the matched population without SRC, individuals with SRC were significantly more likely to have TAD (10.1% vs 3.9%), ascending aortic aneurysm (8.0% vs 3.2%), descending aortic aneurysm (3.3% vs 0.9%), type A aortic dissection (0.6% vs 0.2%), type B aortic dissection (1.1% vs 0.3%) and AAA (7.9% vs 3.3%). The 920 patients identified with BAA were significantly more likely to have TAD (21.8% vs 4.5%), ascending aortic aneurysm (18.4% vs 3.2%), descending aortic aneurysm (6.5% vs 2.0%), type A aortic dissection (1.4% vs 0.4%) and type B aortic dissection (2.4% vs 0.7%) than the matched population without BAA. SRC and BAA were found to be significantly associated with the presence of TAD (OR=2.57 and 7.69, respectively) and AAA (OR=2.81 and 2.56, respectively) on multivariable analysis.

Conclusions

This study establishes a substantial increased prevalence of aortic disease among patients with SRC and BAA. SRC and BAA should be considered markers for aortic aneurysm development.

Ruptured Sinus of Valsalva Aneurysm Associated with Situs Ambiguus, Isolated Levocardia, and Polysplenia

Aneurysm of the sinus of Valsalva, a rare cardiac condition, results from dilation of an aortic sinus. Sudden aneurysm rupture can trigger rapidly progressive heart failure. We discuss the case of a 57-year-old woman with situs ambiguus, isolated levocardia, and polysplenia who presented with acute-onset heart failure. Transesophageal echocardiograms revealed an aneurysm of the right coronary sinus of Valsalva that had ruptured into the right atrial cavity. The patient underwent successful surgical repair. To our knowledge, this is the first report of a sinus of Valsalva aneurysm in a patient with this combination of congenital abnormalities. We briefly review the association between congenital heart disease, situs ambiguus, and ciliary dysfunction.

Height alone, rather than body surface area, suffices for risk estimation in ascending aortic aneurysm

BACKGROUND

In international guidelines, risk estimation for thoracic ascending aortic aneurysm (TAAA) is based on aortic diameter. We previously introduced the aortic size index (ASI), defined as aortic size/body surface area (BSA), as a predictor of aortic dissection, rupture, and death. However, weight might not contribute substantially to aortic size and growth. We seek to evaluate the height-based aortic height index (AHI) versus ASI for risk estimation and revisit our natural history calculations.

METHODS

Aortic diameters and long-term complications of 780 patients with TAAA were analyzed. Growth rate estimates, yearly complication rates, and survival were assessed. Risk stratification was performed using regression models. The predictive value of AHI and ASI was compared.

RESULTS

Patients were stratified into 4 categories of yearly risk of complications based on their ASI and AHI. ASIs (cm/m²) of ≤2.05, 2.08 to 2.95, 3.00 to 3.95 and ≥4, and AHIs (cm/m) of ≤2.43, 2.44 to 3.17, 3.21 to 4.06, and ≥4.1 were associated with a 4%, 7%, 12%, and 18% average yearly risk of complications, respectively. Five-year complication-free survival was progressively worse with increasing ASI and AHI. Both ASI and AHI were shown to be significant predictors of complications (P < .05). AHI categories 3.05 to 3.69, 3.70 to 4.34, and ≥4.35 cm/m were associated with a significantly increased risk of complications (P < .05). The overall fit of the model using AHI was modestly superior according to the concordance statistic.

CONCLUSIONS

Compared with indices including weight, the simpler height-based ratio (excluding weight and BSA calculations) yields satisfactory results for evaluating the risk of natural complications in patients with TAAA.

Is there a role for biomarkers in thoracic aortic aneurysm disease?

Thoracic aortic aneurysm (TAA) represents a major cause of mortality and morbidity in Western countries. The natural history of TAA is indolent, with patients usually being asymptomatic until a catastrophic event such as rupture or dissection ensues. As such, early diagnosis is crucial and the search is ongoing for a biomarker that can indicate the presence of TAA with sufficient accuracy to act as a screening tool. To date, no such marker has been developed for the diagnosis of non-familial or 'sporadic' TAA. However, our increased understanding of the pathogenesis of both familial and sporadic TAA has suggested potential candidates for diagnostic biomarkers. Many markers/pathways have been shown to have differential activity levels or expression in the aortic tissue of TAA. However, priority is given to markers that have shown differential levels in blood plasma, as blood tests represent the easiest route for mass screening for TAA. This review aims to evaluate the efficacy of clinical tests already in use in diagnosing TAA, explore novel proposed biomarkers and identify key areas of future interest.

Differentially expressed genes and canonical pathways in the ascending thoracic aortic aneurysm - The Tampere Vascular Study

Ascending thoracic aortic aneurysm (ATAA) is a multifactorial disease with a strong inflammatory component. Surgery is often required to prevent aortic rupture and dissection. We performed gene expression analysis (Illumina HumanHT-12 version 3 Expression BeadChip) for 32 samples from ATAA (26 without/6 with dissection), and 28 left internal thoracic arteries (controls) collected in Tampere Vascular study. We compared expression profiles and conducted pathway analysis using Ingenuity Pathway Analysis (IPA) to reveal differences between ATAA and a healthy artery wall. Almost 5000 genes were differentially expressed in ATAA samples compared to controls. The most downregulated gene was homeobox (HOX) A5 (fold change, FC = -25.3) and upregulated cadherin-2 (FC = 12.6). Several other HOX genes were also found downregulated (FCs between -25.3 and -1.5, FDR < 0.05). 43, mostly inflammatory, canonical pathways in ATAA were found to be significantly (p < 0.05, FDR < 0.05) differentially expressed. The results remained essentially the same when the 6 dissected ATAA samples were excluded from the analysis. We show for the first time on genome level that ATAA is an inflammatory process, revealing a more detailed molecular pathway level pathogenesis. We propose HOX genes as potentially important players in maintaining aortic integrity, altered expression of which might be important in the pathobiology of ATAA.

Painless Aortic Dissection-Diagnostic Dilemma With Fatal Outcomes: What Do We Learn?

Aortic dissection is the most catastrophic clinical condition that involves the aorta. It has a high mortality as well as high rate of misdiagnosis due to frequent unusual presentation. Typically, it presents with acute chest, back, and tearing abdominal pain. However, it can present atypically with minimal or no pain, making diagnosis difficult. Physicians should always suspect acute aortic dissection in patients with certain clinical conditions like difficult-to-control hypertension, giant cell arteritis, bicuspid aortic valve, intracranial aneurysms, simple renal cysts, family history of aortic disease, and Marfan syndrome, especially when a patient presents with ischemic symptoms involving multiple organ without an obvious cause.