Systemic artery to pulmonary artery aneurysm malformations associated with variants at MCF2L

Arteriovenous malformations (AVM) are characterized by abnormal vessels connecting arteries and veins resulting in a disruption of normal blood flow. Hereditary hemorrhagic telangiectasia (HHT) is the most common cause of pulmonary AVM characterized by a right to left shunt. Here we describe a distinct malformation where the flow of blood was from a systemic artery to the pulmonary artery (PA) resulting in a left to right shunt instead of the right to left shunt seen in individuals with HHT. This distinct malformation was identified in seven probands, one from a multiplex family containing 10 affected individuals from five generations. To identify the molecular basis of this distinct malformation, we performed exome sequencing (ES) on the seven probands and the affected paternal female cousin from the multiplex family. PhenoDB was used to prioritize candidate causative variants along with burden analysis. We describe the clinical and radiological details of the new systemic artery to PA malformation with or without pulmonary artery aneurysm (SA-PA(A)) and recommend distinct treatment techniques. Moreover, ES analysis revealed possible causative variants identified in three families with variants in a novel candidate disease gene, MCF2L. Further functional studies will be necessary to better understand the molecular mechanisms involved on SA-PA(A) malformation, however our findings suggest that MCF2L is a novel disease gene associated with SA-PA(A).

Assessment of pleural pressure during sleep in Marfan syndrome

STUDY OBJECTIVES

Patients with Marfan syndrome (MFS) have a high risk for aortic aneurysms. They are also susceptible to sleep-disordered breathing that may expose them to highly negative intrathoracic pressures known to increase aortic transmural pressure which may accelerate aortic dilatation. Our objective was to quantify overnight intrathoracic pressure changes during sleep in snoring patients with MFS, and the therapeutic effect of continuous positive airway pressure (CPAP).

METHODS

We used a questionnaire to identify self-reported snoring patients with MFS. In these patients, we monitored intrathoracic pressure using esophageal pressure (Pes) during overnight baseline and CPAP sleep studies. We defined a peak inspiratory Pes (Pes_peak-insp) < - 5 cmH₂O as greater than normal, and examined the distribution of Pes_peak-insp during baseline and CPAP studies.

RESULTS

In our sample of 23 MFS snorers, we found that 70% of sleep breaths exhibited Pes_peak-insp < -5 cmH₂O, with apneas/hypopneas accounting for only 12%, suggesting prevalent stable flow-limited breathing and snoring. In a subset (n=12) with Pes monitoring during CPAP night, CPAP lowered the mean proportion of breaths with Pes_peak-insp < -5 cmH₂O from 83.7±14.9% to 3.6±3.0% (p<0.001). In addition, contemporaneous aortic root diameter was associated with the mean Pes_peak-insp during IFL and apneas/hypopneas (β= -0.05, r=0.675, p=0.033).

CONCLUSIONS

The sleep state in MFS revealed prolonged exposure to exaggerated negative inspiratory Pes, which was reversible with CPAP. Since negative intrathoracic pressure can contribute to thoracic aortic stress and aortic dilatation, snoring may be a reversible risk factor for progression of aortic pathology in MFS.

Association of sleep apnoea risk and aortic enlargement in Marfan syndrome

Background

Marfan syndrome (MFS) is a connective tissue disorder characterised by complex aortic pathology and a high prevalence of obstructive sleep apnoea (OSA). OSA produces intrathoracic transmural stresses that may accelerate aortic injury. The current study was designed to examine the associations between OSA risk and markers of aortic enlargement in MFS.

Method

Consecutive patients with MFS were recruited at Johns Hopkins if they completed a STOP-BANG survey. Composite survey scores were categorised into those with low OSA risk (STOP-BANG <3) and high OSA risk (STOP-BANG ≥3). Participants’ aortic data were collated to ascertain aortic root diameter, dilatation and prior aortic root replacement. Regression analyses were used to examine associations between OSA risk strata and these aortic parameters.

Results

Of the 89 participants studied, 28% had a high OSA risk and 32% had aortic grafts. Persons with high OSA risk had greater aortic root diameter (mm) (ß=4.13, SE=1.81, p=0.027) and aortic root dilatation (ß=2.80, SE=1.34, p=0.046) compared with those with low OSA risk. In addition, the odds of prior aortic root replacement was three times greater in those with high OSA risk compared with those with low OSA risk.

Conclusion

In MFS, high OSA risk is associated with aortic enlargement and a threefold increased risk of having had prior aortic root replacement. These findings invite further exploration of the relationship between OSA and aortic disease in MFS, and studies to clarify whether targeted interventions for OSA might mitigate aortic disease progression in MFS.

Registration number

IRB00157483.

Massive ductal aneurysm in an asymptomatic child with Loeys-Dietz syndrome

An asymptomatic 3-year-old with Loeys-Dietz Syndrome (LDS) followed for a small patent ductus arteriosus and dilated aorta was found to have a massive ductal aneurysm on routine surveillance cardiac magnetic resonance. The aneurysm was successfully resected. Serial advanced imaging tools are useful in surveillance, diagnosis, and management in patients with LDS.

Predictors of Bicuspid Aortic Valve–Associated Aortopathy in Childhood

Background:

Bicuspid aortic valve (BAV) is the most prevalent congenital heart defect affecting 1% to 2% of the population. It is associated with ascending aorta dilatation. Valve morphology, aortic stenosis (AS), and aortic insufficiency (AI) have been proposed as potential risk factors; however, evaluating their role is difficult, as these factors are inherently related. The aim of this study was to determine whether BAV morphology and dysfunction are independent determinants for ascending aorta dilatation in pediatric patients.

Methods:

A multicenter, retrospective, cross-sectional study of pediatric BAV patients followed since 2004 was performed. Imaging data were assessed for BAV morphology, severity of AS and AI, history of coarctation, and aortic dimensions. Associations were determined using multivariable regression analysis. A subset of patients undergoing aortic interventions (balloon dilation or Ross) were assessed longitudinally.

Results:

Data were obtained from 2122 patients (68% male; median age 10.2 years). Fifty percent of patients had ascending aorta dilatation. Right and noncoronary cusp fusion, increasing AS and AI, and older age were independently associated with ascending aorta dilatation. A history of coarctation was associated with less ascending aorta dilatation. In patients with neither AS nor AI, 37% had ascending aorta dilatation (4% severe). No complications related to aortic dilatation occurred in this cohort. Aortic Z scores were determined, and a Z -score calculator was created for this population.

Conclusions:

In this large pediatric cohort of patients with BAV, valve morphology, AS, and AI are independently associated with ascending aorta dilatation, suggesting that hemodynamic factors influence aortopathy. However, even in BAVs with no AS or AI, there is significant ascending aorta dilatation independent of valve morphology. Interventions that led to changes in degree of AI and AS did not seem to influence change in aortic dimensions. The current BAV cohort can be used as a reference group for expected changes in aortic dimensions during childhood.

Correction: Arterial tortuosity syndrome: 40 new families and literature review

In the published version of this paper the author Neus Baena's name was incorrectly given as Neus Baena Diez. This has now been corrected in both the HTML and PDF versions of the paper.

Chronobiology of Acute Aortic Dissection in the Marfan Syndrome (from the National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions and the International Registry of Acute Aortic Dissection)

Marfan syndrome (MFS) is an autosomal dominant connective tissue disease associated with acute aortic dissection (AAD). We used 2 large registries that include patients with MFS to investigate possible trends in the chronobiology of AAD in MFS. We queried the International Registry of Acute Aortic Dissection (IRAD) and the Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) registry to extract data on all patients with MFS who had suffered an AAD. The group included 257 patients with MFS who suffered an AAD from 1980 to 2012. The chi-square tests were used for statistical testing. Mean subject age at time of AAD was 38 years, and 61% of subjects were men. AAD was more likely in the winter/spring season (November to April) than the other half of the year (57% vs 43%, p = 0.05). Dissections were significantly more likely to occur during the daytime hours, with 65% of dissections occurring from 6 a.m. to 6 p.m. (p = 0.001). Men were more likely to dissect during the daytime hours (6 a.m. to 6 p.m.) than women (74% vs 51%, p = 0.01). These insights offer a glimpse of the times of greatest vulnerability for patients with MFS who suffer from this catastrophic event. In conclusion, the chronobiology of AAD in MFS reflects that of AAD in the general population.

Ten-year longitudinal change in aortic stiffness assessed by cardiac MRI in the second half of the human lifespan: the multi-ethnic study of atherosclerosis

AIMS

Longitudinal determinants of aortic stiffness (AS) measured by magnetic resonance imaging (MRI) have not been assessed in a large community-based population. Our aim was to examine the determinants of change in thoracic AS over 10 years of follow-up in a multi-ethnic population of individuals 45 years of age and older measured by MRI.

METHODS AND RESULTS

We studied 1160 participants (mean age = 60 ± 9 years at baseline, 45% male) with aortic MRI at both the MESA Year 0 and Year 10 examinations. Ascending and descending aorta distensibility (AAD/DAD) and aortic arch pulse-wave velocity (PWV) were measured using MRI. Determinants of the change in AS parameters over 10 years were assessed using linear regression adjusted for baseline values, demographic variables, baseline risk factors and change in risk factors, and chronic risk exposure. AAD and DAD decreased slightly (5% decrease in median for AAD: 1.33-1.26 mmHg(-1) · 10(-3), P = 0.008; 5% decrease in median for DAD: 1.73-1.64 mmHg(-1) · 10(-3), P < 0.001), and PWV increased over 10 years (18% increase in median: 6.8-8.0 m/s P < 0.001). Baseline age was related to a reduction in AAD and DAD and an increase in PWV throughout the follow-up period. Baseline and change in mean blood pressure and continued smoking were associated with a reduction in AAD and an increase in PWV. Furthermore, baseline heart rate was also related to a reduction in AAD and DAD. Blood pressure normalization was related to less aortic stiffening throughout the follow-up period.

CONCLUSIONS

In our longitudinal, community-based cohort study of adult individuals aged 45 years or greater, greater mean blood pressure and a history of smoking history were associated with increased aortic stiffening over 10 years as assessed by MRI.

Utility of molecular analyses in the exploration of extreme intrafamilial variability in the Marfan syndrome

The diagnosis of Marfan syndrome may be hampered by the existence of very mild and atypical cases as well as by marked intrafamilial variability. In these instances, molecular analysis of the fibrillin-1 gene (FBN1) can be helpful to identify individuals at risk. The underlying molecular mechanism for the clinical variability is presently unknown. We performed clinical and molecular studies in 36 subjects from three unrelated families. Expression studies of both FBN1 alleles were performed and related to the clinical severity. In family 1, an overlapping phenotype between Marfan syndrome (MFS) and Weill-Marchesani syndrome is presented. The diagnosis necessitated molecular studies and clinical examination in first-degree relatives. In family 2, the young proband presented with a phenotype overlapping between MFS and the kyphoscoliotic type of Ehlers-Danlos syndrome. Follow-up over time and identification of a FBN1 mutation allowed confirmation of the diagnosis. Mutation analysis enabled us to identify family members with mild expression. Family 3 illustrates the extensive intrafamilial variability in the clinical severity of MFS. Identification of a FBN1 mutation was helpful to identify subjects with mild expression and for the timely diagnosis in a neonate. In families 2 and 3, the relative expression of both FBN1 alleles was not related to clinical severity. We demonstrated that confirmation of the diagnosis of MFS may require detailed and repeated clinical evaluation and thorough family history taking. FBN1 mutation analysis is supportive for the diagnosis in mild and atypical presentations.

Fetal aortic root dilation: a prenatal feature of the Loeys-Dietz syndrome

Loeys-Dietz syndrome is a recently described autosomal dominant disorder with cardinal manifestations in cardiovascular, craniofacial and skeletal systems. Although the disease has some phenotypic overlap with Marfan syndrome, the disease, that is caused by mutations in the transforming growth factor beta-receptor 1 (TGFBR1) or transforming growth factor beta-receptor 2 (TGFBR2) genes, presents many distinctive features and a particularly aggressive cardiovascular course. We describe prenatal identification of an aortic root aneurysm in a fetus of 19 week of gestation as an early marker of Loeys-Dietz syndrome.

A critical analysis of minor cardiovascular criteria in the diagnostic evaluation of patients with Marfan syndrome

PURPOSE

The prevalence of most minor cardiovascular manifestations in Marfan syndrome (MFS) is unknown. We assessed the prevalence of minor cardiovascular manifestations in MFS to evaluate their usefulness in a diagnostic setting.

METHODS

Seventy-seven patients with MFS (aged 4 months to 55 years) underwent echocardiography to assess the presence of mitral valve prolapse and the diameter of the main pulmonary artery. A subset of 29 adult patients with MFS also underwent magnetic resonance imaging evaluation of the diameters of the thoracoabdominal aorta.

RESULTS

Mitral valve prolapse was encountered in 66% of patients with MFS, with an equal distribution of classic and nonclassic mitral valve prolapse. The main pulmonary artery diameter was significantly larger in patients with MFS at all ages when compared with controls. In the adult group (> or = 14 years), we were able to provide a cutoff value of 23 mm to define pulmonary artery dilatation. The descending aorta was enlarged, but with substantial overlap with controls, thus precluding the use of a cutoff value.

CONCLUSIONS

Mitral valve prolapse and main pulmonary artery dilatation are common findings in MFS patients at all ages and are easy to assess with echocardiography. Cutoff values to define dilatation of the descending aorta are hard to define, making them of limited value in the diagnostic evaluation. We recommend echocardiographic evaluation of mitral valve prolapse and main pulmonary artery diameter in patients referred for cardiovascular diagnostic assessment for MFS.

Erich Fischer-brügge (28.12.1904-4.2.1951) -- founder of neurosurgery at the university of Münster

In 1936, Erich Fischer-Brügge, who worked as a surgeon at the University Clinic of Münster, Westfalia, Germany, visited Wilhelm Tönnis in Würzburg, to receive neurosurgical training. He commenced his work in the field of neurosurgery in Münster from 1937. In 1938 he published a new classification of the anterior circulation of cerebral arteries in states of tumorous mass lesions. From 1939 through to the end of WW II, Tönnis and Fischer-Brügge worked closely together, mainly in the field of war surgery. After WW II, in 1949, Fischer-Brügge published another relevant clinical contribution on the "Clivuskantensyndom". He recognised the ipsilateral osseous compression of the oculomotor nerve at the sphenoidal ridge in raised intracranial pressure. Paul Sunder-Plassmann, successor of Hermann Coenen as chief of surgery at the University Clinic in 1946, inhibited Fischer-Brügge's neurosurgical work massively. After numerous unsuccessful applications for newly installed neurosurgical units, Fischer-Brügge died at the age of only 46 years.

Growth rings in the roots of temperate forbs are robust annual markers

There is increasing interest in the analysis of annual growth rings in the secondary root xylem of perennial forbs (herb-chronology). Therefore, we need to verify whether these growth rings are always formed annually. To investigate the formation of root rings we performed common garden experiments at two distinct sites in Switzerland. We grew nine unrelated forb species from seed and subjected them to competition and clipping treatments. Anatomical developments in the roots of the individuals were tracked during five growing seasons. Across all species and treatments at least 94 % of the expected growth rings associated with full growing seasons were identifiable and the development of the anatomical patterns was consistently seasonal. While the distinctness of annual rings varied somewhat between species and sites, the treatments had no effect on the presence of annual rings. In no case were false rings developed. The results of this study demonstrate that the growth rings in the roots of northern temperate forbs represent robust annual growth increments and, hence, can reliably be used in herb-chronological studies of age- and growth-related questions in plant ecology.

Design and expression of chimeric U1/ribozyme transgenes

The U1snRNA/ribozyme/antisense construct (designated U1/ribozyme) is a chimeric transgene that has proven to be very useful for inhibiting the expression of targeted genes in vitro and in vivo. It consists of a combination of hammerhead ribozyme flanked by target-specific antisense sequences that are in turn flanked by the loops and promoter of U1 snRNA. To construct U1/ribozymes, antisense/ribozyme sequences are first designed corresponding to ribozyme-cleavage consensus "GUC" sequences that are present in the targeted mRNA. Antisense/ribozyme sequences are then inserted between the U1 snRNA loops, and the conceptual secondary structure of the encoded regulatory RNA is analyzed to ensure proper folding. Appropriate antisense/ribozymes are then synthesized as oligonucleotides, annealed, and ligated into the pU1 vector containing the U1 snRNA promoter and loops to yield the pU1/ribozyme expression vector. Constructs can then be transiently or stably expressed in vitro and in vivo to inhibit the expression of target genes. U1/ribozymes can also be expressed in viral vectors for more efficient transfection, or complexed to liposomes for systemic delivery.

Comparative analysis of growth rings in perennial forbs grown in an Alpine restoration experiment

Recent studies have demonstrated that growth rings are widespread in the roots of forbs, and there is evidence that the rings are formed annually. However, the annual nature and development of the growth rings has not yet been examined in comparative experimental studies. In this study growth rings were analysed in the main roots of four alpine forbs (Lotus alpinus, Trifolium thalii, Silene willdenowii and Potentilla aurea) that were grown in an alpine restoration experiment for 6 years. All individuals of L. alpinus and T. thalii, and some individuals of S. willdenowii showed six clearly demarcated growth rings, demonstrating that the rings were formed annually. P. aurea did not show distinguishable growth rings. In L. alpinus and T. thalii there were fluctuations in growth ring width that were consistent between individuals and also between species, and matched variations in climatic growth conditions. Results of the present study indicate that conclusions drawn from previous studies suggesting that growth rings in the roots of forb species are most likely formed annually are also valid for alpine plants. In terms of annual ring width patterns, this study also provides the first strong evidence for consistent responses of different forb species and individuals to commonly experienced variations in habitat conditions.

Biliary atresia: which factors predict the success of a Kasai operation? An analysis of 36 patients

Biliary atresia (BA) is one of the most frequent causes of neonatal cholestasis. Portoenterostomy is one therapeutic option in these patients with a success rate of 30-40%. To answer the question of therapy liver transplantation or Kasai operation - we analyzed 36 consecutive patients being followed in our center during the past 7 years. Two groups were formed: group I : patients developing cirrhosis within the first 2 years of life with the need for liver transplantation (n = 21). Group II: patients without need for transplantation within the first 2 years of life (n = 15). The two groups were compared regarding birth weight, age at diagnosis, age at Kasai-procedure, liver histology. The following biochemical parameters were analyzed at the time of diagnosis, 1 week and 5 weeks after Kasai: AST, ALT, gammaGT, and bilirubin. -

RESULTS

Clinical characteristics were similar in both groups. However BA was diagnosed in group I 8.2 weeks after birth compared to 5.6 wk in group II. gammaGT, ALT, AST, and bilirubin were similar in both groups at the time of diagnosis and 1 wk after Kasai. However 5 wk after Kasai gammaGT was 276 U/l in group I compared to 72 U/l in group II (p <0.001), bilirubin was 6.3mg/dl in group I compared to 2. 3mg/dl in group II (p <0.001). -

CONCLUSION

Kasai operation before the 7th wk of life increases the success rate of this technique significantly. Children with cirrhosis at the time of diagnosis should be evaluated for primary liver transplantation. gammaGT and bilirubin 5 weeks after Kasai operation may be useful markers for the success of this procedure. Patients with a gammaGT > 100 U/l and a bilirubin level >5mg/dl should be followed closely and should be evaluated for liver transplantation early.