Monitoring of congenital heart disease (CHD) and aortic dilatation in Turner syndrome: Italian experience

Increased prevalence of bicuspid aortic valve in Turner syndrome links with karyotype: the crucial importance of detailed cardiovascular screening

BACKGROUND

Bicuspid aortic valve (BAV) represents one of the strongest risk factors for aortic dissection in Turner syndrome (TS). An exact relation between the occurrence of BAV and a particular karyotype has not been established yet. The aim of this study was to determine the association between karyotype and prevalence of BAV.

METHODS

Sixty-seven TS patients aged between 6.6 and 32.5 years underwent cardiac magnetic resonance imaging (MRI) study. They were divided into four cytogenetic subgroups-45,X karyotype (n=27); 45,X/46,XX mosaicism (n=17); structural abnormalities of the X chromosome (n=10); and 45,X/structural abnormality of the X chromosome mosaicism (n=13). Prevalence of BAV and odds ratio (OR) compared with the general population in the whole study group, and statistical comparison of prevalences of BAV among the individual subgroups were determined.

RESULTS

Prevalence of BAV in the whole study group was established as 28.4% [OR 208.3 (95% CI - 103.8-418.0); p-value<0.0001]. Individuals with 45,X karyotype had the highest prevalence of BAV - 40.7%, p-value<0.0001. Presence of any 45,X cell line in karyotype significantly predisposed to BAV (p-value=0.05).

CONCLUSIONS

The 45,X karyotype is associated with the highest prevalence of BAV. Also, the presence of the 45,X cell line in any mosaic karyotype increases the probability of BAV.

Proximal aortic stiffening in Turner patients may be present before dilation can be detected: a segmental functional MRI study

BACKGROUND

To study segmental structural and functional aortic properties in Turner syndrome (TS) patients. Aortic abnormalities contribute to increased morbidity and mortality of women with Turner syndrome. Cardiovascular magnetic resonance (CMR) allows segmental study of aortic elastic properties.

METHOD

We performed Pulse Wave Velocity (PWV) and distensibility measurements using CMR of the thoracic and abdominal aorta in 55 TS-patients, aged 13-59y, and in a control population (n = 38;12-58y). We investigated the contribution of TS on aortic stiffness in our entire cohort, in bicuspid (BAV) versus tricuspid (TAV) aortic valve-morphology subgroups, and in the younger and older subgroups.

RESULTS

Differences in aortic properties were only seen at the most proximal aortic level. BAV Turner patients had significantly higher PWV, compared to TAV Turner (p = 0.014), who in turn had significantly higher PWV compared to controls (p = 0.010). BAV Turner patients had significantly larger ascending aortic (AA) luminal area and lower AA distensibility compared to both controls (all p < 0.01) and TAV Turner patients. TAV Turner had similar AA luminal areas and AA distensibility compared to Controls. Functional changes are present in younger and older Turner subjects, whereas ascending aortic dilation is prominent in older Turner patients. Clinically relevant dilatation (TAV and BAV) was associated with reduced distensibility.

CONCLUSION

Aortic stiffening and dilation in TS affects the proximal aorta, and is more pronounced, although not exclusively, in BAV TS patients. Functional abnormalities are present at an early age, suggesting an aortic wall disease inherent to the TS. Whether this increased stiffness at young age can predict later dilatation needs to be studied longitudinally.

Arterial hypertension in Turner syndrome: a review of the literature and a practical approach for diagnosis and treatment

Turner syndrome is a rare chromosomal disorder with complete or partial absence of one X chromosome that only occurs in women. Clinical presentation is variable, but congenital and acquired cardiovascular diseases are frequently associated diseases that add significantly to the increased morbidity and mortality in Turner syndrome patients. Arterial hypertension is reported in 13-58% of adult Turner syndrome patients and confers an increased risk for stroke and aortic dissection. Hypertension can be present from childhood on and is reported in one-quarter of the paediatric Turner syndrome patients. This article reviews the prevalence and cause of arterial hypertension in Turner syndrome and describes the relationship between blood pressure, aortic dilation and increased cardiovascular risk. We compare current treatment strategies and also propose an integrated practical approach for the diagnosis and treatment of hypertension in Turner syndrome applicable in daily practice.

Cardiovascular pathology in males and females with 45,X/46,XY mosaicism

CONTEXT

The phenotype of 45,X/46,XY mosaicism is heterogeneous ranging from females with Turner syndrome (TS) to apparently normal males. Males with 45,X/46,XY frequently show stigmata typically associated with TS. We hypothesised that males with 45,X/46,XY have similar cardiovascular pathology as females with 45,X/46,XY.

OBJECTIVE

To investigate cardiovascular abnormalities in 45,X/46,XY males and to compare them with 45,X/46,XY females.

DESIGN

Patients with 45,X/46,XY mosaicism were selected from the Belgian Registry for Growth and Puberty problems and via the multidisciplinary clinic for disorders of sexual development.

PATIENTS

EIGHTEEN PATIENTS WERE INCLUDED: 8 raised as females (F) and 10 as males (M).

INTERVENTION

Complete cardiac examination with blood pressure measurement, ECG, echocardiography and MRI.

MAIN OUTCOME MEASUREMENT

Cardiac parameters were registered for both groups. In a second phase, clinical features and external masculinisation score (EMS) were retrospectively collected from the medical files.

RESULTS

A structural heart defect was diagnosed before inclusion in 1 F with coarctation and 1 M with spontaneously closed VSD. A bicuspid aortic valve was found in 8 (3 F, 5 M). Dilation of the ascending aorta was present in 4 M and was severe in 2 young boys. QTc was prolonged in 3 F and 2 M.

CONCLUSION

Males with 45,X/46,XY mosaicism have similar cardiovascular pathology as 45,X/46,XY females. Dilation of the ascending aorta can be important, also in males. We advise cardiac screening and life-long monitoring in all males with 45,X/46,XY mosaicism according to the existing guidelines for Turner syndrome.