A cross-sectional observational study: assessment of cardiovascular damage in mucopolysaccharidoses mutation carriers

Mucopolysaccharidoses (MPS) are a group of lysosomal storage diseases. Cardiovascular pathology occurs in all types of MPS, represented by valvular defects, myocardial hypertrophy, and coronary artery disease. Cardiovascular abnormalities in parents of patients with MPS are poorly understood, which is the purpose of our work.

During January 2022 to October 2023, a cross-sectional observational study of MPS mutation carriers was conducted in the City Clinical Hospital No. 31, practice base of the Department of Propaedeutics of Internal Disease, Pirogov Russian National Research Medical University, Moscow, Russian Federation. There were 21 consecutive parents of children with MPS examined. All MPS carriers-parents underwent a standard clinical and laboratory examination, electrocardiography (ECG), echocardiography, 24-hour Holter ECG monitoring. Distributions of all parametric characteristics of the patients were not normal, non-parametric criteria were used in statistical calculations. Differences between nominal variables were compared using a Chi-squared test. Fisher's exact test was used when more than 20% of cells with expected frequencies less than 5. P value <0.05 was considered statistically significant. The analysis was performed by a biostatistician using the statistical software SPSS (version 26.0; SPSS Institute, USA) and STATISTICA (version 12.0; StatSoft, USA).

The median (25th and 75th percentiles) of age was 36 [33; 37] years. There were no confirmed myocardial and brain infarctions, nor diabetes mellitus in the examined carriers (81% female). A decrease in left ventricular (LV) ejection fraction <40% was found in 1 (4.8%), up to 40-50% in 2 (9.5%) carriers. LV wall thickness ≥1.5 cm was detected in 14 (66.7%) carriers, asymmetric LV hypertrophy in 18 (85.7%). Thickening of the mitral valve leaflets was detected in 16 (76.2%) carriers. Hydropericardium was detected in 5 (23.8%) carriers. Atrial flutter was registered in 1 (4.8%), paroxysmal supraventricular tachycardia in 7 (33.3%), sinus bradycardia in 3 (14.3%); conduction disorders in 15 (71.4%) carriers. A short PR interval was detected on the ECG in 2 (9.5%) carriers. A prolonged QT interval was registered in 3 (14.3%) of carriers, transient ST-segment depression in 10 (47.6%), ST-segment elevation in 3 (14.3%) carriers.

Our results suggested the possibility of clinical manifestations of cardiac involvement in MPS carriers. Further comparative studies are required in larger populations to assess the rate of progression of the identified abnormalities and the effectiveness of drug therapy in these patients.