Phenotypic Expression and Outcomes in Patients with the p.Arg301Gln GLA Variant in Anderson-Fabry Disease.

The p.Arg301Gln variant in the α -galactosidase A gene (GLA) has been poorly described in the literature. The few reports show controversial information, with both classical and nonclassical Anderson-Fabry Disease (AFD) presentation patterns. The aim of this study was to analyze the penetrance, clinical phenotype, and biochemical profile of an international cohort of patients carrying the p.Arg301Gln genetic variant in the GLA gene. This was an observational, international, and retrospective cohort case series study of patients carrying the p.Arg301Gln variant in the GLA gene associated with AFD disease. Forty-nine p.Arg301Gln GLA carriers, 41% male, were analyzed. The penetrance was 63% in the entire cohort and 1.5 times higher in men. The mean age of symptoms onset was 41 years; compared to women, men presented symptoms earlier and with a shorter delay to diagnosis. The typical clinical triad-cornea verticillate, neuropathic pain, and angiokeratomas-affected only 20% of the cohort, with no differences between genders. During follow-up, almost 20% of the patients presented some type of nonfatal cardiovascular and renal event (stroke, need for dialysis, heart failure, and arrhythmias requiring intracardiac devices), predominantly affecting men. Residual levels were the most common finding of α-GAL A enzyme activity, only a few women had a normal level; a small proportion of men had undetectable levels. The incidence of combined outcomes including all causes of death was 33%, and the cumulative incidence of all-cause mortality was 9% at the follow-up. Patients carrying the p.Arg301Gln GLA variant have a high penetrance, with predominantly cardiorenal involvement and clinical onset of the disease in middle age. Only a small proportion showed the classic clinical presentation of AFD. As in other X-linked diseases, males were more affected by severe cardiovascular and renal events. This genotype-phenotype correlation could be useful from a practical clinical point of view and for future decision making.

New Variant in Placophilin-2 Gene Causing Arrhythmogenic Myocardiopathy.

INTRODUCTION: Arrhythmogenic cardiomyopathy (ACM) is an inherited disease characterized by progressive fibroadipose replacement of cardiomyocytes. Its diagnosis is based on imaging, electrocardiographic, histological and genetic/familial criteria. The development of the disease is based mainly on desmosomal genes. Knowledge of the phenotypic expression of each of these genes will help in both diagnosis and prognosis. The objective of this study is to describe the genotype-phenotype association of an unknown PKP2 gene variant in a family diagnosed with ACM. METHODS: Clinical and genetic study of a big family carrying the p.Tyr168* variant in the PKP2 gene, in order to demonstrate pathogenicity of this variant, causing ACM. RESULTS: Twenty-two patients (proband and relatives) were evaluated. This variant presented with high arrhythmic load at an early age, but without evidence of structural heart disease after 20 years of follow-up, with low risk in predictive scores. We demonstrate evidence of its pathogenicity. CONCLUSIONS: The p.Tyr168* variant in the PKP2 gene causes ACM with a high arrhythmic load and with an absence of structural heart disease. This fact emphasizes the value of knowing the phenotypic expression of each variant.

Genotype-Phenotype Correlation in Hypertrophic Cardiomyopathy: New Variant p.Arg652Lys in MYH7.

Hypertrophic cardiomyopathy (HCM) is a genetic disease characterised by increased left ventricle (LV) wall thickness caused by mutations in sarcomeric genes. Finding a causal mutation can help to better assess the proband's risk, as it allows the presence of the mutation to be evaluated in relatives and the follow-up to be focused on carriers. We performed an observational study of patients with HCM due to the novel p.Arg652Lys variant in the MYH7 gene. Eight families and 59 patients are described in the follow-up for a median of 63 months, among whom 39 (66%) carry the variant. Twenty-five (64%) of carriers developed HCM. A median maximum LV wall thickness of 16.5 mm was described. The LV hypertrophy was asymmetric septal in 75% of cases, with LV outflow tract obstruction in 28%. The incidence of a composite of serious adverse cardiovascular events (sudden death, aborted sudden death, appropriate implantable cardiac defibrillator discharge, an embolic event, or admission for heart failure) was observed in five (20%) patients. Given the finding of the p.Arg652Lys variant in patients with HCM, but not in controls, with evident segregation in patients with HCM from eight families and the location in an active site of the protein, we can define this variant as likely pathogenic and associated with the development of HCM.

Reincidencia de eventos coronarios: disfunción endotelial como mediadora / Recurrence of coronary events: endothelial dysfunction as a mediator / Reincidência de eventos coronarianos: disfunção endotelial como mediador

Resumen: Existe evidencia de que luego de un evento coronario (EC) sucede una respuesta inflamatoria que acrecienta la disfunción endotelial y que puede motivar un nuevo EC a corto plazo. Se describe reincidencia de fenómenos isquémicos en el vaso comprometido inicialmente y en otros territorios vasculares. Las modificaciones fisiopatológicas potencialmente terapéuticas no tienen un impacto clínico aplicable en la práctica cardiológica habitual.

Summary: There is evidence that after a coronary event, an inflammatory response is generated, increasing the endothelium dysfunction, which may motivate a new short-term coronary event. Recurrence of ischemic phenomena is described in the vessel involved in the initial event and other vascular territories. Potentially therapeutic physiopathological modifications do not have a clinical impact applicable to usual cardiological practice.

Resumo: Há evidências de que, após a doença arterial coronariana, há inflamação que aumenta a disfunção endotelial e pode levar a mais doenças coronárias em pouco tempo. Se descreve reincidência de fenômenos isquêmicos no vaso comprometido inicialmente e em outros territórios vasculares. As alterações fisiopatológicas potencialmente terapêuticas não têm impacto clínico que possa ser aplicado na prática cardiológica habitual.