The effect of beta-blocker therapy on clinical outcome in patients with Marfan's syndrome: a meta-analysis

Investigation of Strategies to Block Downstream Effectors of AT1R-Mediated Signalling to Prevent Aneurysm Formation in Marfan Syndrome

Cardiovascular outcome in Marfan syndrome (MFS) patients most prominently depends on aortic aneurysm progression with subsequent aortic dissection. Angiotensin II receptor blockers (ARBs) prevent aneurysm formation in MFS mouse models. In patients, ARBs only slow down aortic dilation. Downstream signalling from the angiotensin II type 1 receptor (AT1R) is mediated by G proteins and β-arrestin recruitment. AT1R also interacts with the monocyte chemoattractant protein-1 (MCP-1) receptor, resulting in inflammation. In this study, we explore the targeting of β-arrestin signalling in MFS mice by administering TRV027. Furthermore, because high doses of the ARB losartan, which has been proven beneficial in MFS, cannot be achieved in humans, we investigate a potential additive effect by combining lower concentrations of losartan (25 mg/kg/day and 5 mg/kg/day) with barbadin, a β-arrestin blocker, and DMX20, a C-C chemokine receptor type 2 (CCR2) blocker. A high dose of losartan (50 mg/kg/day) slowed down aneurysm progression compared to untreated MFS mice (1.73 ± 0.12 vs. 1.96 ± 0.08 mm, p = 0.0033). TRV027, the combination of barbadin with losartan (25 mg/kg/day), and DMX-200 (90 mg/kg/day) with a low dose of losartan (5 mg/kg/day) did not show a significant beneficial effect. Our results confirm that while losartan effectively halts aneurysm formation in Fbn1C1041G/+ MFS mice, neither TRV027 alone nor any of the other compounds combined with lower doses of losartan demonstrate a notable impact on aneurysm advancement. It appears that complete blockade of AT1R function, achieved by administrating a high dosage of losartan, may be necessary for inhibiting aneurysm progression in MFS.

Aorta pathology and pregnancy-related risks in adult congenital cardiac disease: does the aorta dilate during pregnancy?

Background

Aortic dilatation and pregnancy are major concerns in women with aortopathy (AOP). This single-centre retrospective analysis focuses on the evolution of aortic diameters during and after pregnancy in women with Marfan syndrome (MS), Turner syndrome (TS) and bicuspid aortic valve (BAV) aortopathy.

Methods and results

Thirty-eight women who had one or more single pregnancies were included. The ascending aorta was measured during pregnancy and postpartum. During pregnancy, a significant increase of diameters of the sinus aortae (median 1.4 mm; [-1.3; 3.8]) and ascending aorta (median 2.1 mm; [0.0; 4.0]) was noted. Systemic hypertension gives dilation of the aorta, but it did not influence the overall trajectory during pregnancy.

Conclusion

Significant aortic dilatation is noted during pregnancy in women with underlying AOP, even persisting in the long term. Pre-existing systemic hypertension is associated with larger aortic diameters prior to pregnancy. More research on a larger study population however is needed.

Drug-based cardiovascular prevention in patients with Marfan Syndrome: a systematic review

INTRODUCTION

Marfan Syndrome (MFS) is a rare and complex genetic disorder associated with increased aortic growth and aortic disease. The effectiveness of cardiovascular medical therapies aiming to slow down aortic growth has been tested in several trials, particularly beta-blockers and angiotensin receptor blockers, however showing conflicting results.

EVIDENCE ACQUISITION

We conducted a systematic review on PubMed (Medline), Cochrane library, Google Scholar, and Biomed Central databases between January and February 2022. We selected relevant articles focusing on patients with MFS treated with beta-blockers, angiotensin receptors blockers, or both, and reporting data on the effect of the drugs on 1) slowing down aortic dilatation; 2) the reduction of aortic complication (aortic dissection, mortality, aortic surgery); and with a 3) follow-up length of at least two years. A total of 16 studies were selected.

EVIDENCE SYNTHESIS

Beta-blockers remain the mainstay of therapy as they have proven to slow aortic enlargement. Angiotensin receptor blockers are a useful alternative and with proven benefit as an add-on therapy to limit aortic growth. Neither beta-blockers, nor angiotensin receptor blockers have shown meaningful results on clinical aortic endpoints.

CONCLUSIONS

The current evidence of pharmacological treatment for MFS patients is conflicting due to the lack of large, randomized clinical trials with adequate follow-up studies and homogeneous age grouping. Beta-blockers and angiotensin receptor blockers are the only available treatments to reduce aortic growth. A recently published patient-level meta-analysis confirmed that angiotensin receptor blockers and beta-blockers have a similar effect on reducing the rate of increase of the aortic root Z score, used singularly or as add-on therapy. Considering the current evidence on new features related with MFS (such as mitral annular disjunction - MAD) bearing a potential additional increased arrhythmic risk, it is of paramount importance to establish the role of beta-blockers and angiotensin receptor blockers in clinical endpoints of this population as well.

Multi-omics in thoracic aortic aneurysm: the complex road to the simplification

BACKGROUND

Thoracic aortic aneurysm (TAA) is a serious condition that affects the aorta, characterized by the dilation of its first segment. The causes of TAA (e.g., age, hypertension, genetic syndromes) are heterogeneous and contribute to the weakening of the aortic wall. This complexity makes treating this life-threatening aortopathy challenging, as there are currently no etiological therapy available, and pharmacological strategies, aimed at avoiding surgical aortic replacement, are merely palliative. Recent studies on novel therapies for TAA have focused on identifying biological targets and etiological mechanisms of the disease by using advanced -omics techniques, including epigenomics, transcriptomics, proteomics, and metabolomics approaches.

METHODS

This review presents the latest findings from -omics approaches and underscores the importance of integrating multi-omics data to gain more comprehensive understanding of TAA.

RESULTS

Literature suggests that the alterations in TAA mediators frequently involve members of pro-fibrotic process (i.e., TGF-β signaling pathways) or proteins associated with cell/extracellular structures (e.g., aggrecans). Further analyses often reported the importance in TAA of processes as inflammation (PCR, CD3, leukotriene compounds), oxidative stress (chromatin OXPHOS, fatty acids), mitochondrial respiration and glycolysis/gluconeogenesis (e.g., PPARs and HIF1a). Of note, more recent metabolomics studies added novel molecular markers to the list of TAA-specific detrimental mediators (proteoglycans).

CONCLUSION

It is increasingly clear that integrating data from different -omics branches, along with clinical data, is essential as well as complicated both to reveal hidden relevant information and to address complex diseases such as TAA. Importantly, recent progresses in metabolomics highlighted novel potential and unprecedented marks in TAA diagnosis and therapy.

Angiotensin receptor blockers and β blockers in Marfan syndrome: an individual patient data meta-analysis of randomised trials

BACKGROUND

Angiotensin receptor blockers (ARBs) and β blockers are widely used in the treatment of Marfan syndrome to try to reduce the rate of progressive aortic root enlargement characteristic of this condition, but their separate and joint effects are uncertain. We aimed to determine these effects in a collaborative individual patient data meta-analysis of randomised trials of these treatments.

METHODS

In this meta-analysis, we identified relevant trials of patients with Marfan syndrome by systematically searching MEDLINE, Embase, and CENTRAL from database inception to Nov 2, 2021. Trials were eligible if they involved a randomised comparison of an ARB versus control or an ARB versus β blocker. We used individual patient data from patients with no prior aortic surgery to estimate the effects of: ARB versus control (placebo or open control); ARB versus β blocker; and indirectly, β blocker versus control. The primary endpoint was the annual rate of change of body surface area-adjusted aortic root dimension Z score, measured at the sinuses of Valsalva.

FINDINGS

We identified ten potentially eligible trials including 1836 patients from our search, from which seven trials and 1442 patients were eligible for inclusion in our main analyses. Four trials involving 676 eligible participants compared ARB with control. During a median follow-up of 3 years, allocation to ARB approximately halved the annual rate of change in the aortic root Z score (mean annual increase 0·07 [SE 0·02] ARB vs 0·13 [SE 0·02] control; absolute difference -0·07 [95% CI -0·12 to -0·01]; p=0·012). Prespecified secondary subgroup analyses showed that the effects of ARB were particularly large in those with pathogenic variants in fibrillin-1, compared with those without such variants (heterogeneity p=0·0050), and there was no evidence to suggest that the effect of ARB varied with β-blocker use (heterogeneity p=0·54). Three trials involving 766 eligible participants compared ARBs with β blockers. During a median follow-up of 3 years, the annual change in the aortic root Z score was similar in the two groups (annual increase -0·08 [SE 0·03] in ARB groups vs -0·11 [SE 0·02] in β-blocker groups; absolute difference 0·03 [95% CI -0·05 to 0·10]; p=0·48). Thus, indirectly, the difference in the annual change in the aortic root Z score between β blockers and control was -0·09 (95% CI -0·18 to 0·00; p=0·042).

INTERPRETATION

In people with Marfan syndrome and no previous aortic surgery, ARBs reduced the rate of increase of the aortic root Z score by about one half, including among those taking a β blocker. The effects of β blockers were similar to those of ARBs. Assuming additivity, combination therapy with both ARBs and β blockers from the time of diagnosis would provide even greater reductions in the rate of aortic enlargement than either treatment alone, which, if maintained over a number of years, would be expected to lead to a delay in the need for aortic surgery.

FUNDING

Marfan Foundation, the Oxford British Heart Foundation Centre for Research Excellence, and the UK Medical Research Council.

Beta-blocker Use After Thoracic Endovascular Aortic Repair in Patients with Type B Aortic Dissection Is Associated with Improved Early Aortic Remodeling

OBJECTIVE

Beta-blockers are first-line anti-impulse therapy in patients presenting with acute type B aortic dissection (TBAD). However, little is understood about their impact after aortic repair. The aim of this study was to evaluate the role of postoperative beta-blocker use on outcomes of thoracic endovascular aortic repair (TEVAR) in TBAD.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing TEVAR for TBAD from 2012 to 2020. Aortic-related reintervention, all-cause mortality and effect of TEVAR on false lumen thrombosis of the treated aortic segment were assessed and compared between patients treated with and without beta-blocker postoperatively. Cox proportional hazards models were used to estimate the effect of beta-blocker therapies on outcomes.

RESULTS

1,114 patients undergoing TEVAR for TBAD were identified with a mean follow-up of 18±12 months. The mean age was 61.1±11.9 years, and 791 (71%) were male. 935 (84%) patients were maintained on beta-blocker at discharge and follow-up. Patients on beta-blocker were more likely to have an entry tear originating in zones 1-2 (22% vs 13%; P=.022). The prevalence of acute, elective and symptomatic AD, concurrent aneurysm, number of endografts used, distribution of the proximal and distal zones of dissection and operative time were comparable between the two cohorts. At 18-months, significantly more complete false lumen thrombosis (58 vs 47%; log-rank P=.018) was observed in patients on beta-blocker while the rates of aortic-related reinterventions (13% vs 9%; log-rank P=.396) and mortality (0.2% vs 0.7%; log-rank P=.401) were similar in patients with and without beta-blocker, respectively. Even after adjusting for clinical and anatomic factors, postoperative beta-blocker use was associated with increased complete false lumen thrombosis (HR 1.56; 95% CI: 1.10-2.21; P=.012) but did not affect mortality or aortic-related reintervention. A secondary analysis of beta-blocker use in acute versus chronic TBAD showed a higher rate of complete false lumen thrombosis in patients on beta-blocker in chronic TBAD (59% vs 38%; log-rank P=.038). In contrast, there was no difference in the rate of complete false lumen thrombosis in acute TBAD between the two cohorts (58% vs 51%; log-rank P=.158). When analyzed separately, postoperative ACE inhibitor use did not affect the rates of complete false lumen thrombosis, mortality and aortic-related reintervention.

CONCLUSIONS

Beta-blocker use was associated with promotion of complete false lumen in patients undergoing TEVAR for TBAD. In addition to its role in acute setting, anti-impulse control with beta-blocker appears to confer favorable aortic remodeling and may improve outcomes after TEVAR, particularly for chronic TBAD.

An update of medical care in Marfan syndrome

Marfan syndrome (MFS), a multisystemic connective disorder, caused by fibrillin 1 gene mutations with autosomal dominant inheritance. The disease spectrum is wide and the major causes of death are related to aortic root aneurysm or dissection. The purposes of medical treatment are to reduce structural changes in the aortic wall and slow aortic root dilatation. Advance in medical researches have provided new insights into the pathogenesis of disease and opened up new horizons for treatments. Several medications such as angiotensin II type I receptor blockers, β-blockers, angiotensin-converting enzyme inhibitors, calcium channel blockers, tetracyclines, and statins have been studied for the purpose. Currently, the life expectancy of Marfan patients improves significantly and is closes to the general population with proper treatment. In this article, we review and update the medical treatments for patients with MFS.

The NO signalling pathway in aortic aneurysm and dissection

Recent studies have shown that NO is a central mediator in diseases associated with thoracic aortic aneurysm, such as Marfan syndrome. The progressive dilation of the aorta in thoracic aortic aneurysm ultimately leads to aortic dissection. Unfortunately, current medical treatments have neither halt aortic enlargement nor prevented rupture, leaving surgical repair as the only effective treatment. There is therefore a pressing need for effective therapies to delay or even avoid the need for surgical repair in thoracic aortic aneurysm patients. Here, we summarize the mechanisms through which NO signalling dysregulation causes thoracic aortic aneurysm, particularly in Marfan syndrome. We discuss recent advances based on the identification of new Marfan syndrome mediators related to pathway overactivation that represent potential disease biomarkers. Likewise, we propose iNOS, sGC and PRKG1, whose pharmacological inhibition reverses aortopathy in Marfan syndrome mice, as targets for therapeutic intervention in thoracic aortic aneurysm and are candidates for clinical trials.

Oxidative Stress-Related Susceptibility to Aneurysm in Marfan's Syndrome

The involvement of highly reactive oxygen-derived free radicals (ROS) in the genesis and progression of various cardiovascular diseases, including arrhythmias, aortic dilatation, aortic dissection, left ventricular hypertrophy, coronary arterial disease and congestive heart failure, is well-established. It has also been suggested that ROS may play a role in aortic aneurysm formation in patients with Marfan's syndrome (MFS). This syndrome is a multisystem disorder with manifestations including cardiovascular, skeletal, pulmonary and ocular systems, however, aortic aneurysm and dissection are still the most life-threatening manifestations of MFS. In this review, we will concentrate on the impact of oxidative stress on aneurysm formation in patients with MFS as well as on possible beneficial effects of some agents with antioxidant properties. Mechanisms responsible for oxidative stress in the MFS model involve a decreased expression of superoxide dismutase (SOD) as well as enhanced expression of NAD(P)H oxidase, inducible nitric oxide synthase (iNOS) and xanthine oxidase. The results of studies have indicated that reactive oxygen species may be involved in smooth muscle cell phenotype switching and apoptosis as well as matrix metalloproteinase activation, resulting in extracellular matrix (ECM) remodeling. The progression of the thoracic aortic aneurysm was suggested to be associated with markedly impaired aortic contractile function and decreased nitric oxide-mediated endothelial-dependent relaxation.

An Overview of Investigational and Experimental Drug Treatment Strategies for Marfan Syndrome

Marfan syndrome (MFS) is a heritable connective tissue disorder caused by pathogenic variants in the gene coding for the extracellular matrix protein fibrillin-1. While the disease affects multiple organ systems, the most life-threatening manifestations are aortic aneurysms leading to dissection and rupture. Other cardiovascular complications, including mitral valve prolapse, primary cardiomyopathy, and arrhythmia, also occur more frequently in patients with MFS. The standard medical care relies on cardiovascular imaging at regular intervals, along with pharmacological treatment with β-adrenergic receptor blockers aimed at reducing the aortic growth rate. When aortic dilatation reaches a threshold associated with increased risk of dissection, prophylactic surgical aortic replacement is performed. Although current clinical management has significantly improved the life expectancy of patients with MFS, no cure is available and fatal complications still occur, underscoring the need for new treatment options. In recent years, preclinical studies have identified a number of potentially promising therapeutic targets. Nevertheless, the translation of these results into clinical practice has remained challenging. In this review, we present an overview of the currently available knowledge regarding the underlying pathophysiological processes associated with MFS cardiovascular pathology. We then summarize the treatment options that have been developed based on this knowledge and are currently in different stages of preclinical or clinical development, provide a critical review of the limitations of current studies and highlight potential opportunities for future research.

Risk reduction and pharmacological strategies to prevent progression of aortic aneurysms

INTRODUCTION

While size thresholds exist to determine when aortic aneurysms warrant surgical intervention, there is no consensus on how best to treat this disease before aneurysms reach the threshold for intervention. Since a landmark study in 1994 first suggested ß-blockers may be useful in preventing aortic aneurysm growth, there has been a surge in research investigating different pharmacologic therapies for aortic aneurysms - with very mixed results.

AREAS COVERED

We have reviewed the existing literature on medical therapies used for thoracic and abdominal aortic aneurysms in humans. These include ß-blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors as well as miscellaneous drugs such as tetracyclines, macrolides, statins, and anti-platelet medications.

EXPERT OPINION

While multiple classes of drugs have been explored for risk reduction in aneurysm disease, with few exceptions results have been disappointing with an abundance of contradictory findings. The vast majority of studies have been done in patients with abdominal aortic aneurysms or thoracic aortic aneurysm patients with Marfan Syndrome. There exists a striking gap in the literature when it comes to pharmacologic management of non-Marfan Syndrome patients with thoracic aortic aneurysms. Given the differences in pathogenesis, this is an important future direction for aortic aneurysm research.

Aortic disease in Marfan syndrome is caused by overactivation of sGC-PRKG signaling by NO

Thoracic aortic aneurysm, as occurs in Marfan syndrome, is generally asymptomatic until dissection or rupture, requiring surgical intervention as the only available treatment. Here, we show that nitric oxide (NO) signaling dysregulates actin cytoskeleton dynamics in Marfan Syndrome smooth muscle cells and that NO-donors induce Marfan-like aortopathy in wild-type mice, indicating that a marked increase in NO suffices to induce aortopathy. Levels of nitrated proteins are higher in plasma from Marfan patients and mice and in aortic tissue from Marfan mice than in control samples, indicating elevated circulating and tissue NO. Soluble guanylate cyclase and cGMP-dependent protein kinase are both activated in Marfan patients and mice and in wild-type mice treated with NO-donors, as shown by increased plasma cGMP and pVASP-S239 staining in aortic tissue. Marfan aortopathy in mice is reverted by pharmacological inhibition of soluble guanylate cyclase and cGMP-dependent protein kinase and lentiviral-mediated Prkg1 silencing. These findings identify potential biomarkers for monitoring Marfan Syndrome in patients and urge evaluation of cGMP-dependent protein kinase and soluble guanylate cyclase as therapeutic targets.

Aortic aneurysm and dissection, the major problem linked to Marfan syndrome (MFS), lacks effective pharmacological treatment. Here, the authors show that the NO pathway is overactivated in MFS and that inhibition of guanylate cyclase and cGMP-dependent protein kinase reverts MFS aortopathy in mice.

Is Aortic Z-score an Appropriate Index of Beneficial Drug Effect in Clinical Trials in Aortic Aneurysm Disease?

Aortic Z-score (Z-score) is utilized in clinical trials to monitor the effect of medications on aortic dilation rate in Marfan (MFS) patients. Z-scores are reported in relation to body surface area and therefore are a function of height and weight. However, an information void exists regarding natural, non-pharmacological changes in Z-scores as children age. We had concerns that Z-score decrease attributed to "therapeutic" effects of investigational drugs for Marfan disease connective tissue diseases might simply reflect normal changes ("filling out" of body contour) as children age. This investigation studies natural changes with age in Z-score in normal and untreated MFS children, teasing out normal effects that might erroneously be attributed to drug benefit. (1) We first compared body mass index (BMI) and Z-scores (Boston Children's Hospital calculator) in 361 children with "normal" single echo exams in four age ranges (0 to 1, 5 to 7, 10 to 12, 15 to 18 years). Regression analysis revealed that aging itself decreases ascending Z-score, but not root Z-score, and that increase in BMI with aging underlies the decreased Z-scores. (2) Next, we examined Z-score findings in both "normal" and Marfan children (all pharmacologically untreated) as determined on sequential echo exams over time. Of 27 children without aortic disease with sequential echos, 19 (70%) showed a natural decrease in root Z-score and 24 (89%) showed a natural decrease in ascending Z- score, over time. Of 25 untreated MFS children with sequential echos, 12 (40%) showed a natural decrease in root Z-score and 10 (33%) showed a natural decrease in ascending Z-score. Thus, Z-score is over time affected by natural factors even in the absence of any aneurysmal pathology or medical intervention. Specifically, Z-score decreases spontaneously as a natural phenomenon as children age and with fill out their BMI. Untreated Marfan patients often showed a spontaneous decrease in Z-score. In clinical drug trials in aneurysm disease, decreasing Z-score has been interpreted as a sign of beneficial drug effect. These data put such conclusions into doubt.

Postpartum Stanford type B aortic dissection in a woman with Loeys-Dietz syndrome who underwent a prophylactic aortic root replacement before conception: A case report

OBJECTIVE

Loeys-Dietz syndrome (LDS) is associated with a higher risk of aortic dissections (ADs) during pregnancy and postpartum. However, there is limited evidence about the perinatal management of LDS patients who have undergone prophylactic aortic root replacements (ARRs) before conception.

CASE REPORT

We present the case of a 28-year-old nulliparous pregnant woman with LDS with a pathogenic variant within exon 5 of TGFBR2 (c.1379G > T, p.[Arg460Leu]), who underwent an ARR at 20 years of age. Cardiac echocardiography did not show any significant changes in the aorta during pregnancy, and her blood pressure remained normal. She had a cesarean section at 37 weeks of gestation. She developed an acute Stanford type B AD extending from the aortic arch to the infrarenal aorta 8 days postpartum and underwent a total arch replacement.

CONCLUSION

This case report suggests that patients with LDS after prophylactic ARRs still possess a risk for Stanford type B ADs.

Acute aortic dissection during pregnancy: Trials and tribulations

BACKGROUND

Type A acute aortic dissection (TAAD) during pregnancy is a life-threatening event for both the mother and the unborn baby. Pregnancy has been recognized as an independent risk factor for TAAD, postulated to be due to physiological changes that cause hyperdynamic circulation. This review seeks to outline the current controversies around this unique group.

METHODS

A comprehensive literature search was carried out across large databases to assimilate relevant papers regarding acute aortic dissection in pregnant women.

RESULTS

The presentation can be atypical in many cases and further concern from clinicians of fetal radiation exposure can result in missed or delayed diagnoses. Investigation via the quickest form of imaging, whether computed tomography, magnetic resonance imaging, or transesophageal echocardiography, should be carried out promptly due to the high risk of mortality. Surgical management of TAAD in pregnancy revolves primarily around the decision to deliver the fetus concomitantly or to perform the aortic repair with the fetus in utero.

CONCLUSIONS

Management of this group includes rapid and dynamic assessment without delay. From conception to postpartum, there are multiple stages in which to manage these women. Challenges in carrying out management in the form of operative techniques and cardiopulmonary bypass place the fetus at risk and must be approached with caution, particularly as there is little evidence-base for many of these decisions. Further research into reducing maternal and fetal mortality is necessary.

The Importance of Genetic Factors in the Management of Spontaneous Pneumothorax

Purpose of Review

Spontaneous pneumothoraces can be the presenting phenotype in a variety of different syndromic genetic conditions. Respiratory physicians therefore have the opportunity to diagnose and manage these patients early to prevent serious complications associated with these syndromes.

Recent Findings

The genetic syndromes that present with pneumothoraces can be split broadly between those resulting from defective extracellular matrix formation and those caused by defective tumour-suppressor pathways. When connective tissues are weakened, lifelong surveillance for arterial dilatation can be life-saving as surgical intervention is effective. Long-term aggressive treatment of blood pressure can also commence, although some controversy surrounds which drugs are most effective and precisely how these drugs modify disease progression. Rational treatments of syndromes in which tumour suppressor function is lost are being developed and, in some instances, can already be offered.

Summary

Careful clinical assessment of spontaneous pneumothorax may identify an underlying causal condition and facilitate life-saving intervention. Respiratory physicians must therefore be aware of these diseases and their diagnostic criteria.

Oxidant/Antioxidant Profile in the Thoracic Aneurysm of Patients with the Loeys-Dietz Syndrome

Patients with the Loeys-Dietz syndrome (LDS) have mutations in the TGF-βR1, TGF-βR2, and SMAD3 genes. However, little is known about the redox homeostasis in the thoracic aortic aneurysms (TAA) they develop. Here, we evaluate the oxidant/antioxidant profile in the TAA tissue from LDS patients and compare it with that in nondamaged aortic tissue from control (C) subjects. We evaluate the enzymatic activities of glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD) isoforms, and thioredoxin reductase (TrxR). We also analyze some antioxidants from a nonenzymatic system such as selenium (Se), glutathione (GSH), and total antioxidant capacity (TAC). Oxidative stress markers such as lipid peroxidation and carbonylation, as well as xanthine oxidase (ORX) and nuclear factor erythroid 2-related factor 2 (Nrf2) expressions, were also evaluated. TAA from LDS patients showed a decrease in GSH, Se, TAC, GPx, GST, CAT, and TrxR. The SOD activity and ORX expressions were increased, but the Nrf2 expression was decreased. The results suggest that the redox homeostasis is altered in the TAA from LDS patients, favoring ROS overproduction that contributes to the decrease in GSH and TAC and leads to LPO and carbonylation. The decrease in Se and Nrf2 alters the activity and/or expression of some antioxidant enzymes, thus favoring a positive feedback oxidative background that contributes to the TAA formation.

Repurposing of drugs approved for cardiovascular diseases: Opportunity or mirage?

Drug repurposing is a promising way in drug discovery to identify new therapeutic uses -different from the original medical indication- for existing drugs. It has many advantages over traditional approaches to de novo drug discovery, since it can significantly reduce healthcare costs and development timeline. In this review, we discuss the possible repurposing of drugs approved for cardiovascular diseases, such as β-blockers, angiotensin converting enzyme inhibitors (ACE-Is), angiotensin II receptor blockers (ARBs), statins, aspirin, cardiac glycosides and low-molecular-weight heparins (LMWHs). Indeed, numerous experimental and epidemiological studies have reported promising anti-cancer activities for these drugs. It is worth mentioning, however, that the results of these studies are often controversial and very few data were obtained by controlled prospective clinical trials. Therefore, no final conclusion has yet been reached in this area and no final recommendations can be made. Moreover, β-blockers, ARBs and statins showed promising results in randomised controlled trials (RCTs) where pathological conditions other than cancer were considered. The results obtained have led or may lead to new indications for these drugs. For each drug or class of drugs, the potential molecular mechanisms of action justifying repurposing, results obtained in vitro and in animal models and data from epidemiological and randomized studies are described.

Successful repair of acute type A aortic dissection during pregnancy at 16th gestational week with maternal and fetal survival: A case report and review of the literature

BACKGROUND

Aortic dissection during pregnancy is a rare but life-threatening event for mothers and fetuses. It often occurs in the third trimester of pregnancy and the postpartum period. Most patients have connective tissue diseases such as Marfan syndrome. Thus, the successful repair of a sporadic aortic dissection with maternal and fetal survival in the early second trimester is extremely rare.

CASE SUMMARY

A 28-year-old woman without Marfan syndrome presented with chest pain at the 16^th gestational week. Aortic computed tomographic angiography confirmed an acute type A aortic dissection (TAAD) with aortic arch and descending aorta involvement. Preoperative fetal ultrasound confirmed that the fetus was stable in the uterus. The patient underwent total arch replacement with a frozen elephant trunk using moderate hypothermic circulatory arrest with the fetus in situ. The patient recovered uneventfully and continued to be pregnant after discharge. At the 38^th gestational week, she delivered a healthy female infant by cesarean section. After 2.5 years of follow-up, the patient is uneventful and the child’s development is normal.

CONCLUSION

A fetus in the second trimester may have a high possibility of survival and healthy growth after aortic arch surgery.

Obstetric Management of Loeys-Dietz Syndrome

BACKGROUND

Loeys-Dietz syndrome is associated with arterial tortuosity and aortic dissection. Pregnancy may be a period of increased risk for aortic dissection.

CASE

A 16-year-old primigravid girl was referred to our center with a family history of aortic dissection. Loeys-Dietz syndrome was suspected, and genetic testing confirmed the TGFβ2 (c.988C>T) mutation. A cesarean delivery was performed at 36 weeks of gestation, with no cardiovascular complications. In this case, the uterine vessels were significantly tortuous; this may be an additional finding in Loeys-Dietz syndrome.

CONCLUSION

Women with Loeys-Dietz syndrome warrant special consideration in obstetric management secondary to the risk for aortic dissection. It is recommended that a multidisciplinary team with knowledge about connective tissue disorders and expertise in aortic surgery coordinate maternal obstetric and cardiovascular care.

Maternal and fetal outcomes in pregnancies complicated by Marfan syndrome

OBJECTIVES

Information to guide counselling and management for pregnancy in women with Marfan syndrome (MFS) is limited. We therefore conducted a UK multicentre study.

METHODS

Retrospective observational study of women with MFS delivering between January 1998 and March 2018 in 12 UK centres reporting data on maternal and neonatal outcomes.

RESULTS

In total, there were 258 pregnancies in 151 women with MFS (19 women had prior aortic root replacements), including 226 pregnancies ≥24 weeks (two sets of twins), 20 miscarriages and 12 pregnancy terminations. Excluding miscarriages and terminations, there were 221 live births in 139 women. Only 50% of women received preconception counselling. There were no deaths, but five women experienced aortic dissection (1.9%; one type A and four type B-one had a type B dissection at 12 weeks and subsequent termination of pregnancy). Five women required cardiac surgery postpartum. No predictors for aortic dissection could be identified. The babies of the 131 (65.8%) women taking beta-blockers were on average 316 g lighter (p<0.001). Caesarean section rates were high (50%), particularly in women with dilated aortic roots. In 55 women, echocardiographic aortic imaging was available prepregnancy and postpregnancy; there was a small but significant average increase in AoR size of 0.84 mm (Median follow-up 2.3 months) CONCLUSION: There were no maternal deaths, and the aortic dissection rate was 1.9% (mainly type B). There with no identifiable factors associated with aortic dissection in our cohort. Preconception counselling rates were low and need improvement. Aortic size measurements increased marginally following pregnancy.

The effects of losartan versus beta-blockers on cardiovascular protection in marfan syndrome: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Variable effects of beta-blockers (BB) and/or angiotensin receptor blockers (ARB) were reported to retard aortic root growth in Marfan syndrome (MFS). This study aimed to compare the effects of BB therapy and ARB-related therapies on cardiovascular protection in MFS.

METHODS

Studies of randomized control trials comparing the efficacy of only-BB and ARB-related (only-ARB or ARB-plus-BB) therapies for MFS published before July 31, 2018 in PubMed, Embase, and the Cochrane Library were selected. The outcomes included changes in aortic growth and cardiovascular events.

RESULTS

Eight trials involving 1381 patients were included. Patients received only-BB and ARB-related therapies did not differ significantly in changes in aortic growth (aortic root diameter: standardized mean difference [SMD] = 0.04, 95% confidence interval [CI]: -0.11-0.19, p = 0.63) or cardiovascular events (aortic dissection: Peto odds ratio [OR] = 1.67, 95% CI: 0.42-6.72, p = 0.47; aortic surgery: risk ratio = 0.97, 95% CI: 0.66-1.41, p = 0.86; death: Peto OR = 2.78, 95% CI: 0.39-19.82, p = 0.31). Subgroup analysis revealed that ARB-plus-BB therapy exhibited nonsignificantly better outcomes than only-BB therapy (aortic root diameter: SMD = 0.11, 95% CI: -0.22-0.45, p = 0.52; ascending aorta diameter: SMD = 0.10, 95% CI: -0.07-0.27, p = 0.26; aortic surgery: Peto OR = 1.10, 95% CI: 0.75-1.61, p = 0.62).

CONCLUSION

For cardiovascular protection in MFS, only-ARB therapy is not inferior to only-BB therapy. Moreover, the outcomes of ARB-plus-BB therapy seemed to be favourable to those of only-BB therapy.

Valvular Disease in Marfan Syndrome: Surgical Considerations and Management

PURPOSE OF REVIEW

Detail the current strategies for the management of valve dysfunction in Marfan syndrome (MFS), understand the limitations of surgical interventions, and delineate the likely direction of future innovations.

RECENT FINDINGS

Significant advances in both medical and surgical management of MFS have been made over the last 50 years. This has resulted in improved overall outcomes. As MFS patients age, new clinical challenges that were once rare have emerged and can require complex care strategies. Medical management has seen advances and focuses on anti-impulse and molecular-based pharmacotherapy, along with close monitoring with serial imaging to minimize acute aortic dissection risk by selecting appropriate timing of prophylactic surgical intervention with increasing aortic dimensions. Ongoing trials are evaluating other potential drug therapies with the ultimate goal of targeted treatment. Over the last 50 years, significant advances have been made in the understanding and management of MFS. A move to prophylactic surgery for aortopathy and valve disease has progressed from a valve replacement to a valve-sparing strategy in many cases. However, the durability of these repairs is variable and the possibility of reintervention looms.

In vivo characterization of doxycycline-mediated protection of aortic function and structure in a mouse model of Marfan syndrome-associated aortic aneurysm

Aortic aneurysm is the most life-threatening complication in Marfan syndrome (MFS) patients. Doxycycline, a nonselective matrix metalloproteinases inhibitor, was reported to improve the contractile function and elastic fiber structure and organization in a Marfan mouse aorta using ex vivo small chamber myography. In this study, we assessed the hypothesis that a long-term treatment with doxycycline would reduce aortic root growth, improve aortic wall elasticity as measured by pulse wave velocity, and improve the ultrastructure of elastic fiber in the mouse model of MFS. In our study, longitudinal measurements of aortic root diameters using high-resolution ultrasound imaging display significantly decreased aortic root diameters and lower pulse wave velocity in doxycycline-treated Marfan mice starting at 6 months as compared to their non-treated MFS counterparts. In addition, at the ultrastructural level, our data show that long-term doxycycline treatment corrects the irregularities of elastic fibers within the aortic wall of Marfan mice to the levels similar to those observed in control subjects. Our findings underscore the key role of matrix metalloproteinases during the progression of aortic aneurysm, and provide new insights into the potential therapeutic value of doxycycline in blocking MFS-associated aortic aneurysm.

The relationship between serum apelin levels and aortic dilatation in bicuspid aortic valve patients

OBJECTIVE

The bicuspid aortic valve (BAV) is the most common congenital heart disease. The process of aortic dilatation is not completely clear in patients with the BAV. Apelin is a peptide found at high levels in vascular endothelial cells which has a role in vascular regulation and cardiovascular function. The aim of this study was to determine the relationship between serum apelin levels and ascending aortic dilatation in adult patients with BAV.

DESIGN

This cross-sectional study included 62 patients with isolated BAV and to an age, gender, and body mass index-matched control group of 58 healthy volunteers with tricuspid aortic valve. Transesophageal echocardiography was performed on all patients to determine the type of BAV. Aortic diameters of the aortic root, sinus valsalva, sinotubular junction, and ascending aorta were evaluated with echocardiography. Patients with BAV were divided into two subgroups according to the aortic diameters, as the nondilated BAV group and the dilated BAV group. Serum apelin level was analyzed with ELISA method.

RESULTS

The serum apelin levels of the BAV patients were significantly lower than those of the control group (833.5, 25th-75th percentile (713.5-1745) pg/dL vs 1669 (936-2543) pg/dL; P = 0.006). In the subgroup analysis, serum apelin level was significantly different between the nondilated BAV group and the dilated BAV group [977 (790-2433) pg/dL vs 737 (693-870) pg/dL, P < 0.05] and between the dilated BAV group and the control group [737 (693-870) pg/dL vs 1669 (936-2543) pg/dL, P < 0.001]. In multivariate logistic regression analysis apelin [7.27 (95% CI: 1.73-30.42), P = 0.007] and age [1.05 (95% CI: 0.99-1.20), P = 0.049] were determined as independent predictors for ascending aortic dilatation.

CONCLUSION

Low serum apelin level was associated with dilatation of ascending aortic in BAV patients. However, apelin was not relevant to BAV without aortic dilatation.

Preconception Counseling for Patients With Thoracic Aortic Aneurysms

PURPOSE OF THE REVIEW

Acute aortic dissection is a potentially catastrophic cardiovascular emergency that is associated with a high mortality rate. Pregnancy, with its attendant hormonal and physiological changes, increases the risk of dissection in women with known thoracic aortic aneurysms. In this review, we highlight the importance of preconception counseling to help women with known thoracic aortic aneurysms better understand their risk of dissection and the heritable nature of thoracic aortic disease and its associated syndromes.

RECENT FINDINGS

The risk of aortic dissection during pregnancy differs according to the underlying etiology of thoracic aortic aneurysm and the degree of aortic dilatation at baseline. Guideline-specific management of women with thoracic aortic aneurysms in pregnancy reduces their risk of dissection. Management of pregnant women with thoracic aortic aneurysms requires an intensive multidisciplinary approach to maximize the chances of a successful outcome for both the mother and fetus. Preconception counseling provides an opportunity to optimize patients medically and to consider potential prophylactic aortic repair prior to pregnancy.

The 2017 Seventh World Congress of Pediatric Cardiology & Cardiac Surgery: week in review - adults with CHD

For the first time in 2017 adults with CHD was included in the World Congress of Pediatric Cardiology & Cardiac Surgery. With growing numbers and more complex patients reaching adulthood, there is a growing need for more attention to this subspecialty. Although survival is excellent and now over 90% of patients reach adulthood, many have residual problems and complications. Heart failure and arrhythmias are most commonly encountered. Life-expectancy is nearly normal for mild lesions, but remains reduced in moderate-complex lesions and re-interventions are often needed. As most patients want to live a normal life, sports participation and pregnancy become very important issues. Finally, although innovative treatments are being developed, including for end-stage heart failure, we have to refine strategies for optimal care, including during the end-stage lives of our patients. This article provides an overview of a selection of topics in the field of adults with CHD presented during the 2017 Seventh World Congress of Pediatric Cardiology & Cardiac Surgery (WCPCCS) in Barcelona.

Abnormal Longitudinal Growth of the Aorta in Children with Familial Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) is the most common type of congenital heart defect (CHD) and is associated with clinically significant cardiovascular complications including valve calcification and ascending aortopathy (AscAo), predominantly occurring in adulthood. While a limited number of genetic etiologies for BAV have been defined, family members of affected individuals display BAV along with other left-sided CHD. This has led to guidelines from the American Heart Association and American College of Cardiology that recommend echocardiographic screening of first-degree relatives of affected adults. While potentially beneficial in adults, the yield of such screening in children is unknown. The purpose of this study was to investigate a cohort of children with familial BAV to determine the frequency of development of AscAo, and to identify risk factors that contribute to abnormal aortic growth. Echocardiograms over a 10-year follow-up period were reviewed on 26 patients with familial BAV [22 male, 4 female; 22 with isolated BAV, 6 with BAV and aortic coarctation (CoA)]. All had a family history of CHD and were recruited from 2005 to 2010 as part of a genetics research study. Four aortic segments (annulus, root, sinotubular junction, ascending aorta) on parasternal long-axis echocardiographic images were measured by a single observer. The mean age at first echocardiogram was 7.1 ± 5.5 and that was 13.8 ± 6.2 years at the last echocardiogram. Only patients with > 2 echocardiograms in the 10-year period were included. Z score measurements of the aorta were plotted over time and based on these the cohort was divided into two groups: Group 1 (abnormal)-Z score for any segment > 2 or a change in Z score > 2 over follow-up; Group 2 (normal)-Z score < 2 throughout follow-up and change in Z score < 2. Nineteen out of 26 children displayed abnormal aortic growth or dilation of the aorta. BAV with right/left cusp fusion was more frequent in Group 1 (15/18) versus Group 2 (3/7) (p < 0.05). There were no significant differences in gender, aortic valve dysfunction, presence of CoA, family history, cardiac function, presence of left ventricular hypertrophy, or medication use between the 2 groups. In our longitudinal study of children with familial BAV, the majority display evidence of abnormal growth of the ascending aorta during the follow-up period consistent with AscAo and support the extension of current adult guidelines to the pediatric population. While we find that right/left cusp fusion is a risk factor for abnormal aortic growth, additional studies are needed to identify other factors to better select children who require serial screening.

Beta-blockers for preventing aortic dissection in Marfan syndrome

BACKGROUND

Marfan syndrome is a hereditary disorder affecting the connective tissue and is caused by a mutation of the fibrillin-1 (FBN1) gene. It affects multiple systems of the body, most notably the cardiovascular, ocular, skeletal, dural and pulmonary systems. Aortic root dilatation is the most frequent cardiovascular manifestation and its complications, including aortic regurgitation, dissection and rupture are the main cause of morbidity and mortality.

OBJECTIVES

To assess the long-term efficacy and safety of beta-blocker therapy as compared to placebo, no treatment or surveillance only in people with Marfan syndrome.

SEARCH METHODS

We searched the following databases on 28 June 2017; CENTRAL, MEDLINE, Embase, Science Citation Index Expanded and the Conference Proceeding Citation Index - Science in the Web of Science Core Collection. We also searched the Online Metabolic and Molecular Bases of Inherited Disease (OMMBID), ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) on 30 June 2017. We did not impose any restriction on language of publication.

SELECTION CRITERIA

All randomised controlled trials (RCTs) of at least one year in duration assessing the effects of beta-blocker monotherapy compared with placebo, no treatment or surveillance only, in people of all ages with a confirmed diagnosis of Marfan syndrome were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts for inclusion, extracted data and assessed trial quality. Trial authors were contacted to obtain missing data. Dichotomous outcomes will be reported as relative risk and continuous outcomes as mean differences with 95% confidence intervals. We assessed the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

One open-label, randomised, single-centre trial including 70 participants with Marfan syndrome (aged 12 to 50 years old) met the inclusion criteria. Participants were randomly assigned to propranolol (N = 32) or no treatment (N = 38) for an average duration of 9.3 years in the control group and 10.7 years in the treatment group. The initial dose of propranolol was 10 mg four times daily and the optimal dose was reached when the heart rate remained below 100 beats per minute during exercise or the systolic time interval increased by 30%. The mean (± standard error (SE)) optimal dose of propranolol was 212 ± 68 mg given in four divided doses daily.Beta-blocker therapy did not reduce the incidence of all-cause mortality (RR 0.24, 95% CI 0.01 to 4.75; participants = 70; low-quality evidence). Mortality attributed to Marfan syndrome was not reported. Non-fatal serious adverse events were also not reported. However, study authors report on pre-defined, non-fatal clinical endpoints, which include aortic dissection, aortic regurgitation, cardiovascular surgery and congestive heart failure. Their analysis showed no difference between the treatment and control groups in these outcomes (RR 0.79, 95% CI 0.37 to 1.69; participants = 70; low-quality evidence).Beta-blocker therapy did not reduce the incidence of aortic dissection (RR 0.59, 95% CI 0.12 to 3.03), aortic regurgitation (RR 1.19, 95% CI 0.18 to 7.96), congestive heart failure (RR 1.19, 95% CI 0.18 to 7.96) or cardiovascular surgery, (RR 0.59, 95% CI 0.12 to 3.03); participants = 70; low-quality evidence.The study reports a reduced rate of aortic dilatation measured by M-mode echocardiography in the treatment group (aortic ratio mean slope: 0.084 (control) vs 0.023 (treatment), P < 0.001). The change in systolic and diastolic blood pressure, total adverse events and withdrawal due to adverse events were not reported in the treatment or control group at study end point.We judged this study to be at high risk of selection (allocation concealment) bias, performance bias, detection bias, attrition bias and selective reporting bias. The overall quality of evidence was low. We do not know whether a statistically significant reduced rate of aortic dilatation translates into clinical benefit in terms of aortic dissection or mortality.

AUTHORS' CONCLUSIONS

Based on only one, low-quality RCT comparing long-term propranolol to no treatment in people with Marfan syndrome, we could draw no definitive conclusions for clinical practice. High-quality, randomised trials are needed to evaluate the long-term efficacy of beta-blocker treatment in people with Marfan syndrome. Future trials should report on all clinically relevant end points and adverse events to evaluate benefit versus harm of therapy.

Medical management of aortic disease in Marfan syndrome

Marfan syndrome (MFS) is a hereditary disorder with numerous pathophysiological effects, some specifically creating elastic dysfunction in cardiovascular organs. Aortic dilatation, dissection and rupture are major concerns in the management of MFS patients. Predilection to form aneurysms is an indication for prophylactic medical management of thoracic aortic aneurysm disease in these patients. The current guidelines describe β-blockers as the standard of care with angiotensin receptor blockers (ARBs) emerging as an equal, if not better alternative. We elaborate current evidence for and against different medical regimens used for the medical management of MFS patients.

The Genetics of Aortopathies in Clinical Cardiology

Aortopathies pose a significant healthcare burden due to excess early mortality, increasing incidence, and underdiagnosis. Understanding the underlying genetic causes, early diagnosis, timely surveillance, prophylactic repair, and family screening are keys to addressing these diseases. Next-generation sequencing continues to expand our understanding of the genetic causes of heritable aortopathies, rapidly clarifying their underlying molecular pathophysiology and suggesting new potential therapeutic targets. This review will summarize the pathogenetic mechanisms and management of heritable genetic aortopathies with attention to specific forms of both syndromic and nonsyndromic disorders, including Marfan syndrome, Loeys-Dietz syndrome, vascular Ehlers-Danlos syndrome, and familial thoracic aortic aneurysm and dissection.

Peripartum type B aortic dissection in patients with Marfan syndrome who underwent aortic root replacement: a case series study

OBJECTIVE

To investigate pregnancy outcomes, especially the risk of pregnancy-related aortic dissection (AD), in patients with Marfan syndrome (MFS) after prophylactic aortic root replacement (ARR).

DESIGN

Retrospective case series study.

SETTING

Tertiary perinatal care centre at a university hospital.

POPULATION

Pregnant women fulfilling the revised Ghent nosology (2010) criteria for MFS who were managed at our institute.

METHODS

The pregnancy outcomes of all patients with MFS managed at our institute between 1982 and September 2016 were reviewed retrospectively based on medical records.

MAIN OUTCOME MEASURES

Obstetrical management and complication including the incidence of AD throughout the peripartum period.

RESULTS

Among 22 patients (28 pregnancies) who had been managed as potential MFS or related disorders, 14 (17 pregnancies) fulfilled the revised Ghent nosology (2010) criteria for MFS and were enrolled in this study. Five patients (five pregnancies) had received ARR before conception: three (60%) developed type B aortic dissection [AD(B)] during the peripartum period, compared with only one of 10 patients (12 pregnancies) without ARR (P < 0.05, Chi-square test).

CONCLUSIONS

Our study results suggest that MFS patients after prophylactic ARR are still at high risk of AD(B) during the peripartum period. Careful pre-pregnancy counselling and multidisciplinary care throughout the peripartum period are essential for the management of MFS, even after surgical repair of an ascending aortic aneurysm.

TWEETABLE ABSTRACT

MFS patients after prophylactic ARR are still at high risk of type B aortic dissection during the peripartum period.

Aetiology and management of hereditary aortopathy

Aortic aneurysms are a major health problem because they account for 1-2% of all deaths in the Western population. Although abdominal aortic aneurysms (AAAs) are more prevalent than thoracic aortic aneurysms (TAAs), TAAs have been more exhaustively studied over the past 2 decades because they have a higher heritability and affect younger individuals. Gene identification in both syndromic and nonsyndromic TAA is proceeding at a rapid pace and has already pinpointed >20 genes associated with familial TAA risk. Whereas these genes explain <30% of all cases of familial TAA, their functional characterization has substantially improved our knowledge of the underlying pathological mechanisms. As such, perturbed extracellular matrix homeostasis, transforming growth factor-β signalling, and vascular smooth muscle cell contractility have been proposed as important processes in TAA pathogenesis. These new insights enable novel treatment options that are currently being investigated in large clinical trials. Moreover, together with the advent of next-generation sequencing approaches, these genetic findings are promoting a shift in the management of patients with TAA by enabling gene-tailored interventions. In this Review, we comprehensively describe the molecular landscape of familial TAA, and we discuss whether familial TAA, from a biological point of view, can serve as a paradigm for the genetically more complex forms of the condition, such as sporadic TAA or AAA.