Prevention of Cardiovascular Complications in the Marfan Syndrome

Marfan syndrome

PURPOSE

To provide an overview of Marfan syndrome (MFS), including diagnostic criteria, genetic factors involved, emerging theories for treatment, a case study, and an overview of genetic counseling for individuals and families of those with MFS.

DATA SOURCES

Selected research, review, and clinical articles.

CONCLUSIONS

MFS is a connective tissue disorder with distinct physical characteristics. Recent advances in the field of genetics have traced this disease process to certain gene mutations. Affecting the optical, skeletal and cardiovascular systems, MFS can cause significant morbidity and mortality if left untreated. Close surveillance and early treatment are necessary to ensure a normal life span.

IMPLICATIONS FOR PRACTICE

It is important for the advanced practice nurse (APN) to be aware of the complications in those with MFS. Attentive surveillance can decrease mortality and morbidity associated with this syndrome. A multidisciplinary approach, utilizing the expertize of the APN, is necessary for comprehensive care.

Marfan syndrome: clinical diagnosis and management

Marfan syndrome is a multisystem connective tissue disorder usually associated with mutation in fibrillin, and occasionally with mutation in TGFBR1 or 2. The clinical diagnosis is made using the Ghent nosology, which will unequivocally diagnose or exclude Marfan syndrome in 86% of cases. Use of a care pathway can help implementation of the nosology in the clinic. The penetrance of some features is age dependent, so the nosology must be used with caution in children. Molecular testing may be helpful in this context. The nosology cannot be used in families with isolated aortic dissection, or with related conditions such as Loeys-Dietz syndrome, although it may help identify families for further diagnostic evaluation because they do not fulfill the nosology, despite a history of aneurysm. Prophylactic medical (eg beta-blockade) and surgical intervention is important in reducing the cardiovascular complications of Marfan syndrome. Musculoskeletal symptoms are common, although the pathophysiology is less clear--for example, the correlation between dural ectasia and back pain is uncertain. Symptoms in other systems require specialist review such as ophthalmology assessment of refractive errors and ectopia lentis. Pregnancy is a time of increased cardiovascular risk for women with Marfan syndrome, particularly if the aortic root exceeds 4 cm at the start of pregnancy. High-intensity static exercise should be discouraged although low-moderate intensity dynamic exercise may be beneficial. The diagnosis and management of Marfan syndrome requires a multidisciplinary team approach, in view of its multisystem effects and phenotypic variability.

Current concepts of ocular manifestations in Marfan syndrome

Marfan syndrome is a widespread disorder of connective tissue. It is characterized by systemic and ocular features due to mutations in the fibrillin gene. Awareness and prompt recognition of the ocular complications of Marfan syndrome may enable improvement and preservation of sight. Studies have been performed in the last few years that enable a better understanding of the genetics of the syndrome, earlier diagnosis, and improvement in the surgical techniques and options.

Marfan syndrome: what internists and pediatric or adult cardiologists need to know

Marfan syndrome (MFS) is one of the most frequent connective tissue disorders, showing striking pleiotropism and clinical variability. There is autosomal dominant inheritance with complete penetrance but variable expression. Approximately 25% of MFS patients have no family history of the syndrome and represent sporadic cases due to new mutations. This hazardous condition is often associated with premature cardiovascular death unless surveillance and management are optimized. The fibrillin gene (FBN1) encodes the structure of the connective tissue protein fibrillin. MFS is caused by mutations in the fibrillin gene, located on chromosome 15 at locus 15q21. Fibrillin abnormalities reduce the structural integrity of different body systems, primarily involving the heart valves, blood vessels, lungs, bones, tendons, ligaments, cartilages, eyes, skin, spinal dura and the CNS. Patients with MFS are likely to have too little fibrillin within these structures, resulting in clinically relevant problems. For example, in the aortic wall, deficient fibrillin may trigger progressive aortic ectasia and may result in aortic dissection.

Obstetric complications in Marfan syndrome

OBJECTIVE

To investigate the obstetric maternal and neonatal outcome of pregnancy in women with Marfan syndrome.

METHODS

Retrospective observational multi-center study based on congenital heart disease registry.

RESULTS

Sixty-three of the 122 enrolled women with Marfan syndrome had been pregnant 142 times (including 111 pregnancies>20 weeks, 28 (20%) miscarriages and 3 elective abortions). In 40% of all completed pregnancies an obstetric and/ or neonatal complication occurred. The most important complications were an increased percentage of premature deliveries (n=17, 15%) mainly due to preterm premature rupture of membranes and cervical incompetence and a markedly increased combined fetal and neonatal mortality of 7.1%. An obstetric and/or neonatal complication occurred in a similar proportion of pregnancies in women with a diagnosis of Marfan syndrome before pregnancy versus women with a diagnosis of Marfan syndrome after pregnancy (39% vs. 41%, p=0.85, respectively).

CONCLUSION

In addition to cardiovascular complications, pregnancy in women with Marfan syndrome is associated with a high rate of premature deliveries, preterm premature rupture of membranes and increased mortality in the offspring.

A bioinformatics framework for genotype–phenotype correlation in humans with Marfan syndrome caused by FBN1 gene mutations

Mutations in the human FBN1 gene are known to be associated with the Marfan syndrome, an autosomal dominant inherited multi-systemic connective tissue disorder. However, in the absence of solid genotype-phenotype correlations, the identification of an FBN1 mutation has only little prognostic value. We propose a bioinformatics framework for the mutated FBN1 gene which comprises the collection, management, and analysis of mutation data identified by molecular genetic analysis (DHPLC) and data of the clinical phenotype. To query our database at different levels of information, a relational data model, describing mutational events at the cDNA and protein levels, and the disease's phenotypic expression from two alternative views, was implemented. For database similarity requests, a query model which uses a distance measure based on log-likelihood weights for each clinical manifestation, was introduced. A data mining strategy for discovering diagnostic markers, classification and clustering of phenotypic expressions was provided which enabled us to confirm some known and to identify some new genotype-phenotype correlations.