Pectus updates and special considerations in Marfan syndrome

Paediatric syndromic scoliosis: proceedings of the half-day course at the 57th annual meeting of the Scoliosis Research Society

There are some syndromes that present with unique manifestations pertaining to the spinal column. A good working understanding of these common syndromes is useful for the spinal deformity surgeons and related healthcare providers. This review attempts to encompass these unique features and discuss them in three broad groups: hypermobility syndromes, muscle pathology-related syndromes, and syndromes related to poor bone quality. This review explores the features of these syndromes underpinning the aspects of surgical and medical management. This review represents the proceedings of the Paediatric Half-Day Course at the 57th Annual Meeting of the Scoliosis Research Society.

Outcomes of the Nuss procedure in children with pectus excavatum: 14 years of experience

BACKGROUND

We aimed to assess the effectiveness of the Nuss procedure for pectus excavatum (PE) and explore the impacts of sex and age on outcomes.

METHODS

We retrospectively reviewed 594 consecutive children ≤18 years of age who underwent the thoracoscopy-assisted Nuss technique between January 2006 and July 2019. The severity of pectus deformity was calculated according to the Haller index (HI). The classification of PE and clinical data including complications was analyzed.

RESULTS

Of the 594 patients, 456 (76.8%) were boys and 138 (23.2%) were girls. The mean age at surgery was 10.0 ± 5.0 years. The most common types of PE were 1A and 2A2 according to Park classification. Intraoperative and postoperative complication rates were 2/594 (0.3%) and 74/594 (12.5%), respectively. The most common complication was bar displacement. The bar was removed in 414 patients 3.5 ± 0.8 years later. The mean preoperative HI, postoperative HI with bar, and HI after bar removal were 4.2 ± 1.7, 2.4 ± 0.3, and 2.7 ± 0.5, respectively. Compared to the preoperative HI, both the postoperative HI with bar and HI after bar removal were significantly lower ( p < 0.001). For preschool-age children, the preoperative HI was significantly higher ( p = 0.027) and the change in HI significantly improved compared to school-age children ( p = 0.004). Boys and adolescents needed significantly more bars and stabilizers.

CONCLUSION

Surgical correction of PE using the Nuss procedure is a safe procedure and improves the HI in children of different ages, even in those younger than 6 years of age.

Is physical activity a future therapy for patients with Marfan syndrome?

Introduction

The international recommendations tend to avoid physical activity (PA) for patients with Marfan syndrome (MFS). However, exceptions have recently been made in the most recent recommendations for these patients, suggesting benefits from doing PA at low intensity only. Furthermore, there is no evidence that moderate aerobic or weight training can worsen the disease symptoms and increase mortality of MFS patients. The present review sums up the work carried out in the field of PA and MFS. The review aims to (1) identify the different types of exercise testing and training protocols and (2) discuss the feasibility and potentially beneficial nature of PA as an innovative way to manage MFS patients.

Methods

The scientific literature was reviewed using the following words: Marfan syndrome, training, physical activity, evaluation, weight training, arterial disease, aneurysms, lung damage, aortic dissection, rupture. A total of 345 studies were prospected and 43 studies were included.

Conclusions

A limited number of studies were done in humans, however one demonstrated the feasibility of the management of MFS patients with PA. There were potential beneficial effects of PA on arterial structures, but this review also showed deleterious effects when PA was conducted at high intensities, corresponding to 75–85% of the maximal oxygen uptake. However, these effects have only been reported in animal studies.

The Musculoskeletal Manifestations of Marfan Syndrome: Diagnosis, Impact, and Management

Purpose of Review

Marfan syndrome (MFS) is an autosomal dominant heritable disorder of fibrillin-1 (FBN1) with predominantly ocular, cardiovascular, and musculoskeletal manifestations that has a population prevalence of approximately 1 in 5–10,000 (Chiu et al. Mayo Clin Proc. 89(1):34–42, 146, Dietz 3, Loeys et al. J Med Genet. 47(7):476–85, 4).

Recent Findings

The vascular complications of MFS still pose the greatest threat, but effective management options, such as regular cardiac monitoring and elective surgical intervention, have reduced the risk of life-threatening cardiovascular events, such as aortic dissection. Although cardiovascular morbidity and mortality remains high, these improvements in cardiovascular management have extended the life expectancy of those with MFS by perhaps 30–50 years from an estimated mean of 32 years in 1972 (Dietz 3, Gott et al. Eur J Cardio-thoracic Surg. 10(3):149–58, 147, Murdoch et al. N Engl J Med. 286(15):804–8, 148). The musculoskeletal manifestations of MFS, which to date have received less attention, can also have a significant impact on the quality of life and are likely to become more important as the age of the Marfan syndrome population increases (Hasan et al. Int J Clin Pract. 61(8):1308–1320, 127). In addition, musculoskeletal manifestations are often critically important in the diagnosis of MFS.

Summary

Here, we review the main clinically relevant and diagnostically useful musculoskeletal features of MFS, which together contribute to the “systemic features score” (referred to hereafter as systemic score), part of the revised Ghent nosology for MFS. We discuss current treatment strategies and highlight the need for a multidisciplinary approach to diagnosis and management. Finally, we review new pharmacological approaches that may be disease modifying and could help to improve the outcome for individuals with this syndrome.

Respiratory manifestations of Marfan syndrome: a narrative review

Objective

The prevalence of Marfan syndrome (MFS) is estimated to be 1 in 10,000 to 15,000 individuals, but the phenotype of MFS may not be apparent and hence its diagnosis may not be considered by clinicians. Furthermore, the effects of MFS on the lungs and breathing are underrecognized despite the high morbidity that can occur. The objective of this Narrative Review is to delineate the molecular consequences of a defective fibrillin-1 protein and the skeletal and lung abnormalities in MFS that may contribute to respiratory compromise. It is important for clinicians to be cognizant of these MFS-associated respiratory conditions, and a contemporaneous review is needed.

Background

MFS is an autosomal dominant, connective tissue disorder caused by mutations in the FIBRILLIN-1 (FBN1) gene, resulting in abnormal elastic fibers as well as increased tissue availability of transforming growth factor-beta (TGFβ), both of which lead to the protean clinical abnormalities. While these clinical characteristics are most often recognized in the cardiovascular, skeletal, and ocular systems, MFS may also cause significant impairment on the lungs and breathing.

Methods

We searched PubMed for the key words of “Marfan syndrome,” “pectus excavatum,” and “scoliosis” with that of “lung disease,” “breathing”, or “respiratory disease.” The bibliographies of identified articles were further searched for relevant articles not previously identified. Each relevant article was reviewed by one or more of the authors and a narrative review was composed.

Conclusions

Though the classic manifestations of MFS are cardiovascular, skeletal, and ocular, FBN1 gene mutation can induce a variety of effects on the respiratory system, inducing substantial morbidity and potentially increased mortality. These respiratory effects may include chest wall and spinal deformities, emphysema, pneumothorax, sleep apnea, and potentially increased incidence of asthma, bronchiectasis, and interstitial lung disease. Further research into approaches to prevent respiratory complications is needed, but improved recognition of the respiratory complications of MFS is necessary before this research is likely to occur.

Impact of chest wall deformity on cardiac function by CMR and feature-tracking strain analysis in paediatric patients with Marfan syndrome

Objectives

To evaluate systolic cardiac dysfunction in paediatric MFS patients with chest wall deformity using cardiac magnetic resonance (CMR) imaging and feature-tracking strain analysis.

Methods

Forty paediatric MFS patients (16 ± 3 years, range 8−22 years) and 20 age-matched healthy controls (16 ± 4 years, range 11−24 years) were evaluated retrospectively. Biventricular function and volumes were determined using cine sequences. Feature-tracking CMR was used to assess global systolic longitudinal (GLS), circumferential (GCS) and radial strain (GRS). A dedicated balanced turbo field echo sequence was used to quantify chest wall deformity by measuring the Haller index (HI).

Results

LV volumes and ejection fraction (EF) were similar in MFS patients and controls. There was a trend for lower right ventricular (RV) volume (75 ± 17 vs. 81 ± 10 ml/m², p = 0.08), RV stroke volume (41 ± 12 vs. 50 ± 5 ml/m², p < 0.001) and RVEF (55 ± 10 vs. 62 ± 6%, p < 0.01) in MFS patients. A subgroup of MFS patients had an increased HI compared to controls (4.6 ± 1.7 vs. 2.6 ± 0.3, p < 0.001). They demonstrated a reduced RVEF compared to MFS patients without chest wall deformity (50 ± 11% vs. 58 ± 8%, p = 0.01) and controls (p < 0.001). LV GLS was attenuated when HI ≥ 3.25 (- 16 ± 2 vs. - 18 ± 3%, p = 0.03), but not GCS and GRS. LV GLS (p < 0.01) and GCS (p < 0.0001) were attenuated in MFS patients compared to controls, but not GRS (p = 0.31). RV GLS was attenuated in MFS patients compared to controls (- 21 ± 3 vs. - 23 ± 3%, p < 0.05).

Conclusion

Chest wall deformity in paediatric MFS patients is associated with reduced RV volume, ejection fraction and GLS. Feature-tracking CMR also indicates impairment of systolic LV function in paediatric MFS patients.

Key Points

• Paediatric Marfan patients demonstrate reduced RV volume and ejection fraction compared to healthy controls.

• A concordant attenuation in RV global longitudinal strain was observed in Marfan patients, while the RV global circumferential strain was increased, indicating a possible compensatory mechanism.

• Subgroup analyses demonstrated alterations in RV ejection fraction and RV/LV global strain parameters, indicating a possible association of severe chest wall deformity with biventricular dysfunction in paediatric Marfan patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-020-07616-9.