Objective: To assess the association of T190C polymorphism of β3 adrenergic receptor gene (β3-AR) with chronic heart failure (CHF), and to evaluate the effect of this polymorphism on clinical response to β-AR blockade among patients with CHF.
Methods: Three hundred and thirty patients with stable CHF receiving basic therapy for heart failure were included. Before initiation and 5 months after the maximal tolerated dose of carvedilol was reached, all indices including heart rate (HR), blood pressure (BP), left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular ejection fraction (LVEF), brain natriuretic peptide (BNP) level, 6 min walk distance were measured and compared with the indices of those with a T190C genotype. Distribution of the T190C polymorphisms in the control group and CHF group was compared.
Results: The frequencies of T190C genotypes of the β3-AR gene have fit with the Hardy-Weinberg equilibrium. No significant difference was found between the frequencies of T190C alleles and genotypes between the two groups (P > 0.05). Compared with CC-homozygotes, TT-homozygous patients showed substantially greater improvement in LVEF and BNP (all P < 0.01).
Conclusion: No difference has been detected in the prevalence of the three genotypes between healthy and CHF subjects. The T190C variation of the β3-AR gene was not associated with increased risk for CHF. CHF patients with a T allele have greater response to carvedilol than those carrying a C allele in ethnic Han Chinese.