ABSTRACT
BACKGROUND: Hereditary transthyretin (ATTRv) p.Val142Ile (V122I) mutation is the most common inherited cause of cardiac amyloidosis and little is known about the phenotype and outcome of the rare homozygotic genotype. This study aimed to compare phenotypic characteristics and outcomes between heterozygous and homozygous patients with ATTRv V122I amyloidosis. MATERIAL AND METHODS: This monocentric, observational, retrospective study conducted at the French National Referral Centre for Cardiac Amyloidosis (Henri Mondor Hospital, Créteil), described clinical, electrocardiographic, cardiac imaging features and prognostic data for patients with ATTRv V122I amyloidosis. RESULTS: Among 185 ATTRv V122I patients identified, 161 were heterozygous and 24 were homozygous. The homozygous frequency was 13%. Onset occured significantly earlier in the homozygotes compared to heterozygotes with earlier median age at diagnosis (67[63-71] years vs 76[70-79] years, p < .001), age at first cardiac symptom (66[61-71] years vs 74[68-78] years, p < .001) and age at first extracardiac symptom (59[52-70] years vs 69[62-75] years, p = .003). Homozygous ATTRv V122I was also associated with greater disease burden with earlier events (death, transplant or hospitalisation for acute heart failure) compared with heterozygotes (71[67-74] vs 78[76-79] years, p = .018). CONCLUSION: This rare, homozygous V122I cohort confirmed the earlier age of onset, death and cardiac events in this population.
Subject(s)
Amyloid Neuropathies, Familial , Prealbumin , Humans , Middle Aged , Aged , Cohort Studies , Homozygote , Heterozygote , Retrospective Studies , Prealbumin/genetics , Amyloid Neuropathies, Familial/genetics , Amyloid Neuropathies, Familial/complicationsABSTRACT
Infiltrative cardiomyopathies are abnormal accumulations or depositions of different substances in cardiac tissue leading to its dysfunction, first diastolic, then systolic. The different infiltrative cardiomyopathies are amyloidosis (both light chain amyloidosis and transthyretin amyloidosis variants), lysosomal and glycogen storage disorders (Fabry-Anderson disease), and iron overload (hemochromatosis and thalassemia associated with blood transfusions), as well as inflammatory diseases such as sarcoidosis. We also evoke hypereosinophilic syndrome associated with endomyocardial fibrosis. Echocardiography is the first essential step after interrogatory and clinical examination and may help the cardiologist as a screening tool. Cardiac MRI is the second fundamental step towards the diagnosis especially due to the late gadolinium enhancement and to the T1-mapping. Cardiac amyloidosis diagnosis also requires the use of nuclear imaging. Cardiac CT-Scan may be useful for estimating the amyloid load, identify potential cardiac thrombus and rule out associated coronaropathy.
