Aortic Root Dilatation in Mucopolysaccharidosis I–VII

Abstract

The prevalence of aortic root dilatation (ARD) in mucopolysaccharidosis (MPS) is not well documented. We investigated aortic root measurements in 34 MPS patients at the Children’s Hospital of Orange County (CHOC). The diagnosis, treatment status, age, gender, height, weight and aortic root parameters (aortic valve annulus (AVA), sinuses of Valsalva (SoV), and sinotubular junction (STJ)) were extracted by retrospective chart review and echocardiographic measurements. Descriptive statistics, ANOVA, and paired post-hoc t-tests were used to summarize the aortic dimensions. Exact binomial 95% confidence intervals (CIs) were constructed for ARD, defined as a z-score greater than 2 at the SoV. The patient age ranged from 3.4–25.9 years (mean 13.3 ± 6.1), the height from 0.87–1.62 meters (mean 1.24 ± 0.21), and the weight from 14.1–84.5 kg (mean 34.4 ± 18.0). The prevalence of dilation at the AVA was 41% (14/34; 95% CI: 25%–59%); at the SoV was 35% (12/34; 95% CI: 20%–54%); and at the STJ was 30% (9/30; 95% CI: 15%–49%). The highest prevalence of ARD was in MPS IVa (87.5%). There was no significant difference between mean z-scores of MPS patients who received treatment with hematopoietic stem cell transplantation (HSCT) or enzyme replacement therapy (ERT) vs. untreated MPS patients at the AVA (z = 1.9 ± 2.5 vs. z = 1.5 ± 2.4; p = 0.62), SoV (z = 1.2 ± 1.6 vs. z = 1.3 ± 2.2; p = 0.79), or STJ (z = 1.0 ± 1.8 vs. z = 1.2 ± 1.6; p = 0.83). The prevalence of ARD was 35% in our cohort of MPS I–VII patients. Thus, we recommend screening for ARD on a routine basis in this patient population.

Cardiac disease in mucopolysaccharidosis type III

“…In our cohort, there was no significantly higher incidence of ARD at the SoV compared to controls. In contrast, two recent publication reported a higher incidence of ARD in MPS patients, respectively in 39.1% and 35% . However, Poswar et al did not include any MPS III patients in their study, and Bolourchi et al reported the same mean ARD at the SoV in 6 MPS III patients as we report in our patients.…”

“…While CD was previously not considered to be present in MPS III, several recent studies reported cardiac involvement . In addition, CD may also be related to sudden unexpected death reported in some patients …”

“…CD in MPSs presents predominantly with valvulopathy, mainly involving the mitral and aortic valves. However, cardiomyopathy, arrhythmias, coronary artery disease, aortic root dilatation and conduction abnormalities have all been reported …”

“…However, cardiomyopathy, arrhythmias, coronary artery disease, aortic root dilatation and conduction abnormalities have all been reported. 4,[7][8][9] While CD was previously not considered to be present in MPS III, several recent studies reported cardiac involvement. [8][9][10][11][12][13] In addition, CD may also be related to sudden unexpected death reported in some patients.…”

“…4,[7][8][9] While CD was previously not considered to be present in MPS III, several recent studies reported cardiac involvement. [8][9][10][11][12][13] In addition, CD may also be related to sudden unexpected death reported in some patients. 12 As a number of disease-modifying treatment options for MPS III are currently being investigated, 14 probably leading to an increase in life expectancy with preservation of cognitive function in the near future, extensive knowledge on the prevalence and nature of CD in MPS III is important.…”