The Frequency of Fabry Disease in Patients with Cardiac Hypertrophy of Various Phenotypes Including Prominent Papillary Muscle: The TUCARFAB Study in Turkey.

BACKGROUND: The present study aimed to identify the frequency of Fabry disease in patients with cardiac hypertrophy of unknown etiology and to evaluate demographic and clinical characteristics, enzyme activity levels, and genetic mutations at the time of diagnosis. METHODS: This national, multicenter, cross-sectional, single-arm, observational registry study was conducted in adult patients with a clinical echocardiographic diagnosis of left ventricular hypertrophy and/or the presence of prominent papillary muscle. In both genders, genetic analysis was performed by DNA Sanger sequence analysis. RESULTS: A total of 406 patients with left ventricular hypertrophy of unknown origin were included. Of the patients, 19.5% had decreased enzyme activity (≤2.5 nmol/mL/h). Although genetic analysis revealed GLA (galactosidase alpha) gene mutation in only 2  patients (0.5%), these patients were considered to have probable but not 'definite Fabry disease' due to normal lyso Gb3 levels and gene mutations categorized as variants of unknown significance. CONCLUSION: The prevalence of Fabry disease varies according to the characteristics of the population screened and the definition of the disease used in these trials. From cardiology perspective, left ventricular hypertrophy is the major reason to consider screening for Fabry disease. Enzyme testing, genetic analysis, substrate analysis, histopathological examination, and family screening should be performed, when necessary, for a definite diagnosis of Fabry disease. The results of this study underline the importance of the comprehensive use of these diagnostic tools to reach a definite diagnosis. The diagnosis and management of Fabry disease should not be based solely on the results of the screening tests.

Detection of Early Right Ventricular Dysfunction in Young Patients With Thalassemia Major Using Tissue Doppler Imaging.

BACKGROUND: Myocardial iron overload is the most common cause of mortality in patients with thalassemia major (TM), also known as beta-thalassemia. T2* cardiovascular magnetic resonance imaging (MRI) is the best way of monitoring cardiac iron, and new echocardiographic techniques can be used to assess cardiac function. OBJECTIVES: The aim of this study was to assess the systolic and diastolic right ventricular (RV) function of patients with TM using tissue Doppler imaging (TDI) and to determine whether this echocardiographic technique is an adequate diagnostic tool for the screening and detection of subclinical cardiac dysfunction. PATIENTS AND METHODS: Eighty-four patients with TM were evaluated by conventional echocardiography and pulse-wave TDI. The data of the TM group (Group 1) were compared with that of 85 age- and sex-matched healthy controls (Group 2). Cardiovascular T2* MRI examinations were performed in 49 of the 85 patients. RESULTS: The patients with TM had significantly lower values for weight, height, body mass index, systolic arterial pressure, deceleration time, E'/A', and ejection time (ET) than the controls. Group 1 also had significantly higher values for peak early diastolic velocity (E) over peak late diastolic velocity (A), peak early diastolic velocity of TDI (E'), peak late diastolic velocity of TDI (A'), E/E', isovolumetric relaxation time, isovolumetric contraction time, and RV magnetic perfusion imaging (MPI) than Group 2. CONCLUSIONS: RV diastolic dysfunction occurs before systolic deterioration in patients with TM and cannot be screened with conventional echocardiographic techniques. In routine practice, TDI measurements, MPI (for global function) and the E/E' parameter (for diastolic function) can be used to screen and detect early RV dysfunction.