Defining the cardiovascular phenotype of adults with Alström syndrome.

BACKGROUND: >40% of infants with Alström Syndrome (AS) present with a transient, severe cardiomyopathy in the first months of life, with apparent recovery in survivors. One in five individuals then develop a later-onset cardiomyopathy but wide clinical variability is observed, even within the same family. The rationale for this study is to provide a comprehensive evaluation of the cardiovascular phenotype in adults with AS. METHODS: Adults attending the National Centre for AS in England were studied. All patients underwent biochemical, 12- lead electrocardiography, echocardiography, and cardiovascular magnetic resonance imaging. RESULTS: 47 adults with AS (64% male; mean age 33 years; 66% white British) were studied. Seven (15%) survived infantile cardiomyopathy and 23 (49%) developed adult-onset cardiomyopathy. Conventional risk factors for cardiovascular disease were present in 39 (83%). Abnormalities were present on biomarkers in 16 (34%), ECG 30 (64%), echocardiography 19 (40%) and CMR 31 (66%). Coronary artery imaging was performed in six (13%), with abnormalities in two. Cardiac, renal, and liver markers were more often impaired in older patients, with impaired left ventricular ejection fraction, reduced global longitudinal strain and late enhancement. 6 (13%) had severe pulmonary hypertension (mean pulmonary artery pressure 46 mmHg) due to left heart disease on invasive testing. CONCLUSION: Cardiomyopathy is common in adults with AS, complicated in a significant proportion by atherosclerotic coronary artery disease and restrictive cardiomyopathy, confirmed on CMR and invasive testing. With advancing age, cardiovascular complications are compounded by contemporaneous renal and liver disease.

Phenoage and longitudinal changes on transthoracic echocardiography in Alström syndrome: a disease of accelerated ageing?

Alström syndrome (AS) is an ultra-rare disorder characterised by early-onset multi-organ dysfunction, such as insulin resistance, obesity, dyslipidaemia, and renal and cardiovascular disease. The objective is to explore whether AS is a disease of accelerated ageing and whether changes over time on echocardiography could reflect accelerated cardiac ageing. Cross-sectional measurement of Phenoage and retrospective analysis of serial echocardiography were performed between March 2012 and November 2022. The setting is a single national tertiary service jointly run by health service and patient charity. Forty-five adult patients aged over 16 years were included, 64% were male and 67% of White ethnicity. The median Phenoage was 48 years (interquartile range [IQR]: 35-72) in the 34 patients for whom this was calculable, which was significantly higher than the median chronological age of 29 years (IQR: 22-39, p<0.001). Phenoage was higher than chronological age in 85% (N=29) of patients, with a median difference of +18 years (IQR: +4, +34). On echocardiography, significant decreases were observed over time in left ventricular (LV) size at end-diastole (average of 0.046 cm per year, p<0.001) and end-systole (1.1% per year, p=0.025), with significant increase in posterior wall thickness at end-diastole (0.009 cm per year, p=0.008). LV systolic function measured by global longitudinal strain reduced (0.34 percentage points per year, p=0.020) and E/e'lat increased (2.5% per year, p=0.019). Most AS patients display a higher Phenoage compared to chronological age. Cardiac changes in AS patients were also reflective of accelerated ageing, with a reduction in LV size and increased wall thickening. AS may be a paradigm disease for premature ageing.