Angiotensin-converting enzyme polymorphism in healthy young subjects: Relationship to left ventricular mass and functions

Abstract

Objectives - Angiotensin-converting enzyme (ACE) is a key enzyme in the production of angiotensin II and thus may participate in the modulation of cardiac growth. The cloning of the ACE gene has made it possible to identify a deletion (D)-insertion (I) polymorphism that appears to affect the level of serum ACE activity. The aim of the study is to analyse the ACE gene I/D polymorphisms in healthy young subjects and to evaluate its relationship to left ventricular mass and functions. Methods - 38 women and 40 men (mean age 21.1 ± 1.7 and 21.4 ± 1.7 years) were studied. They underwent complete echocardiographic assessment and analysis of ACE insertion (I) and deletion (D) allele frequencies in peripheral blood by polymerase chain reaction. Thickness of interventricular septum (IVS) and posterior wall (LVPW) and left ventricular mass (LVM) and LVM index (LVMI) were measured by M-mode. Left ventricular ejection fraction (LVEF) was calculated by Simpson's method. Results - There was no statistically significant difference among the DD, DI and II genotypes, concerning age, body mass index, heart rate, systolic and diastolic blood pressures. The thickness of IVS (9.5 mm), LVPW (9.0 mm), LVM (204.5 g) and LVMI (105.5 g/m2) in DD genotypes were higher than both DI (8.3 mm; 8.1 mm; 168.1 g; 90.9 g/m2) and II genotypes (8.2 mm; 7.0 mm; 141.7 g; 77.8 g/m2) in men, but not in women. LVEF among the 3 genotypes were not statistically different. Conclusion - Our findings suggest that left ventricular hypertrophy is partially determined by genetic disposition especially in men but not in women.