The relationship between blood pressure and left ventricular mass in essential hypertension is observed only in the presence of the angiotensin-converting enzyme gene deletion allele

An insertion/deletion polymorphism in the angiotensin-convertingenzyme (ACE) gene accounts for approximately 50% of the variancein plasma ACE concentration: deletion homozygotes (DD) havethe highest, and insertion homozygotes (II) the lowest ACE concentrations.ACE is responsible for the generation of angiotensin II, whichis implicated in the development of left ventricular hypertrophy,an independent risk factor for morbidity and mortality in hypertension.The aim of this study was to investigate the contribution ofACE genotype to the development of left ventricular hypertrophyin patients with essential hypertension. Eighty-five patientswith essential hypertension underwent echocardiographic assessmentof left ventricular mass index (LVMI) and determination of ACEgenotype from leukocyte DNA by polymerase chain reaction. Therewas no significant difference in LVMI among the genotypes (II,ID, DD). Analysis of covariance modelled for LVMI showed a significantinteraction with systolic blood pressure (p = 0.036). but notdiastolic blood pressure (p = 0.453). The relationship betweenLVMI and systolic blood pressure was strongest in the deletionhomozygotes (p = 0.002, R² = 0.47), and also present in theheterozygotes (p = 0.013, R² = 0.40). No relationship was seenin the insertion homozygotes (p = 0.914, R² = 0.23) These findingssuggest that the effect of blood pressure on LVMI in essentialhypertension is expressed only in the presence of the ACE genedeletion allele.