High Prevalence of Late-Onset Fabry Cardiomyopathy in a Cohort of 499 Non-Selective Patients with Left Ventricular Hypertrophy: The Asian Fabry Cardiomyopathy High-Risk Screening Study (ASIAN-FAME)

Left ventricular hypertrophy (LVH) caused by cardiac variant Fabry disease (FD) is typically late-onset and may mimic LVH caused by abnormal loading conditions. We aimed to determine the prevalence of FD in a non-selective patient population of everyday practice presenting with LVH, including those with hypertension and valve disease. We measured plasma alpha-galactosidase A activity using dried blood spot tests in 499 (age = 66 ± 13 years; 336 men) Hong Kong Chinese patients with LVH defined as maximal LV septal/posterior wall thickness ≥13 mm on echocardiography. Patients with low enzyme activity underwent mutation analysis of the GLA gene. Eight (age = 53−74 years; all men) unrelated patients (1.6%) had low plasma alpha-galactosidase A activity (0.57 ± 0.27 μmol/L wb/hr) and all were confirmed to have the GLA IVS4 + 919G > A mutation. FD patients presented with heart failure (n = 5), heart block (n = 2), ventricular tachycardia (n = 1), chest pain (n = 3), and/or murmur (n = 1). Uncontrolled hypertension (n = 4) and/or severe mitral/aortic valve pathology (n = 2) were frequent. Ethnic subgroups included Teochew (n = 5), Canton (n = 2), and Wenzhou (n = 1). Endomyocardial biopsy (n = 6) revealed hypertrophic myocytes with vacuolization and dense lamellar bodies. Late-onset IVS4 + 919G > A FD is prevalent among Chinese LVH patients, and should be considered as a cause of LVH in adult patients even when hypertension and/or valve pathology are present.

Glenoid bone loss: assessment with MR imaging

PURPOSE

To investigate the agreement among magnetic resonance (MR) imaging, computed tomography (CT), and arthroscopy in the measurement of glenoid bone loss.

MATERIALS AND METHODS

This study was approved by the institutional ethics committee. One hundred seventy-six patients (158 male and 18 female patients; mean age, 26.8 years ± 12.3) with anterior shoulder dislocation underwent both shoulder MR imaging and CT examination. Anterior straight line length, glenoid width, and best-fit bone loss were measured with MR imaging and CT. Sixty-five patients also underwent arthroscopy, which was used as the standard of reference. Assessment of glenoid bone loss at MR imaging was compared with that at CT and arthroscopy. Inter- and intrareader reproducibility of MR imaging-derived measurements of glenoid bone loss was evaluated.

RESULTS

There was excellent correlation between CT and MR imaging with regard to anterior straight line length (r = 0.97, P < .0001), glenoid width (r = 0.95, P < .0001), and severity of glenoid bone loss-particularly with use of best-fit circle width (r = 0.83, P < .0001) rather than best-fit circle area (r = 0.82, P < .0001). In the assessment of glenoid bone loss, the correlation between CT and arthroscopy (r = 0.91, P < .0001) was marginally better than that between MR imaging and arthroscopy (r = 0.84, P < .0001). The inter- and intrareader correlations of MR imaging-derived measurements of glenoid bone loss were excellent (R = 0.90-0.95).

CONCLUSION

MR imaging assessment of glenoid bone loss, particularly with use of glenoid width, is almost as accurate as CT assessment.