Comparison of subclinical left and right ventricular systolic dysfunction in non-dipper and dipper hypertensives: impact of isovolumic acceleration

Abstract

Objectives: To evaluate subclinical left ventricular and right ventricular systolic impairment in dipper and non-dipper hypertensives by using isovolumic acceleration.Methods: About 45 normotensive healthy volunteers (20 men, mean age 43 ± 9 years), 45 dipper (27 men, mean age 45 ± 9 years) and 45 non-dipper (25 men, 47 ± 7 years) hypertensives were enrolled. Isovolumic acceleration was measured by dividing the peak myocardial isovolumic contraction velocity by isovolumic acceleration time.Results: Non-dippers indicated lower left ventricular (2.2 ± 0.4 m/s2 versus 2.8 ± 1.0 m/s2, p < 0.01) and right ventricular isovolumic acceleration values (2.8 ± 0.8 m/s2 versus 3.5 ± 1.0 m/s2, p = 0.012) compared with dippers. Left ventricular mass index (p = 0.001), interventricular septal thickness (p = 0.002) and myocardial performance index (p < 0.001) were negatively correlated with left ventricular isovolumic acceleration. Left ventricular septal thickness (p = 0.002), mass index (p = 0.001) and right ventricular myocardial performance index (p < 0.001) were negatively correlated with right ventricular isovolumic acceleration.Conclusion: The present study demonstrates that non-dipper hypertensives have increased left and right ventricular subclinical systolic dysfunction compared with dippers. Isovolumic acceleration is the only echocardiographic parameter in predicting this subtle impairment.