ABC | Volume 114, Nº4, April 2020

Short Editorial Pereira-Barretto Genetic Polymorphism Arq Bras Cardiol. 2020; 114(4):625-626 clinical stability of ventricular dysfunction and preserved exercise capacity. Conversely, others, clinically classified as having advanced HF, evolve with a prolonged and unexpected survival. Moreover, the data showed that part of the perceived differences in the effectiveness of beta-blockers, as well as the variability of responses to the latter can be attributed to some genetic variations that affect beta receptors and their signaling pathways. 2,3 In Brazil, the beta-1 receptor polymorphism has been studied in Rio de Janeiro and Rio Grande do Sul. 2,5 In the study discussed in this short editorial, the authors emphasize that the cardiac beta-1 adrenergic receptor (R β 1) is the main structure responsible for mediating the effects of adrenaline and that the sustained stimulation of this system results in multiple deleterious effects, especially cardiotoxicity. Genetic variants are associated with different activities of this receptor. The authors studied the genetic polymorphism identified at position 145 of the nucleotide, in which serine is replaced by glycine at position 49 (R β 1-Ser49Gly). 2 This study describes, in a Brazilian population, the association between the genotypes of the Ser49Gly Beta1- adrenergic Receptor Genetic Polymorphism and the clinical evolution in 178 patients with HF, with a mean follow-up of 6.7 years. 2 This is a study with Ser49Gly genotyping in the context of HF with the longest follow-up time ever published. Its main finding was the association of the Gly-Gly genetic polymorphism with a protective effect for clinical outcomes, with better clinical evolution assessed by NYHA functional class and lower risk of death. The longer follow-up allowed us to better assess the HF evolution aspects and to verify that the Gly allele is associated with better clinical evolution; however, there was a potential influence of ethnicity on these genotypes, reversing this benign behavior in some populations. An important point was to allow the assessment of prognosis in little symptomatic patients, increasing the accuracy of the prognostic evaluation for these patients, as well. As for the prognosis, the results of this study were similar to those obtained in the study carried out in Rio Grande do Sul, 5 adding an important contribution by identifying that patients with the Gly-Gly profile, which is less frequent, remained little symptomatic throughout the follow-up, thus identifying a group of patients with lower evolution potential. 3 However, it should be noted that the assessed sample is small and confirmatory studies are necessary to verify this hypothesis, aiming to show whether the genetic variants of beta-adrenergic receptors can help to identify patients with HF who will have a lower disease progression and whether they will be more responsive to beta-blockers and, as a consequence, have a better clinical evolution. The results allow us to suppose that, in the future, before starting a treatment with neurohormonal blockers or beta-blockers, the genetic profile will be identified, and medications will be prescribed only to those who are responsive to them. 1. Comitê Coordenador da Diretriz Brasileira de Insuficiência Cardíaca Crônica e Aguda, Rohde LEP, Montera MW, Bocchi EA, Clausell NO, Albuquerque DC; Sociedade Brasileira de Cardiologia.. Arq Bras Cardiol. 2018;111(3):436-539. 2. Shin J, Johnson JA. Beta-blocker pharmocogenetics in heart failure. Heart Fail Rev. 2010;15(3):187-96. 3. Albuquerque FN, Brandão AA, Silva DA e cols. Ser49Gly Beta1-adrenergic Receptor genetic Polymorphism as a Death Predictor in Brazilian Patients with Heart Failure. Arq Bras Cardiol. 2020; 114(4):616-624. 4. Melo DSB, Pereira-Barretto AC, Cardoso JN, Oliveira AI, Ochiai ME, Melo FSA, et al. Polimorfismos genéticos como preditores prognósticos em pacientes com insuficiência cardíaca avançada após rápida titulação com betabloqueadores. In: 11 Congresso Brasileiro de Insufiiência Cardíaca. Recife (PE);2012. Arq Bras Cardiol. 2012;99(2 supl 2):1-148. 5. Biolo A, Clausell N, Santos KG, Salvaro R, Ashton-Prolla P, Borges A, et al. Impact of β 1-adrenergic receptor polymorphisms on susceptibility to heart failure, arrhythmogenesis, prognosis, and response to beta-blocker therapy. Am J Cardiol. 2008;102(6):726-32. References This is an open-access article distributed under the terms of the Creative Commons Attribution License 626