High sodium intake modulates left ventricular mass in patients with G expression of +1675 G/A angiotensin II receptor type 2 gene

Objectives In patients with hypertension left ventricular hypertrophy (LVH) is associated with genetic variations of the angiotensin type 2 receptor (AT(2)R). Hypertension and LVH are often aggravated by salt intake. Our objective was to assess the relationship between AT(2)R gene variation and salt intake and their impact on left ventricular mass (LVM). Methods and results In 205 subjects with normal or mildly elevated blood pressure, we assessed sodium intake and left ventricular structure and function by echocardiography. Intronic +1675 G/A polymorphism of the AT(2)R gene was investigated. A-allele carriers had a greater LVM (P = 0.049) than G-allele carriers. Independent of diet, septal wall thickness was higher in A-allele carriers (P = 0.001). Fractional fibre shortening was greater in A-allele carriers (P = 0.034), and the velocity of circumferential fibre shortening tended to be greater in A-allele carriers (P = 0.057). When the two groups were stratified according to their salt intake, only G-allele carriers displayed a modulating effect of salt intake on LVM. Covariance analysis revealed that there was a trend towards a modulating effect of salt intake on LVM, even after taking blood pressure into account (P = 0.054). Conclusion Our data clearly support the notion that LVM is influenced by AT(2)R polymorphisms. Furthermore, G-allele carriers in particular appear to be susceptible to a modifying effect of increased salt intake on LVM.