Relationship Between Masked Hypertension Measured by Ambulatory Blood Pressure Monitoring and Left Ventricular Global Longitudinal Strain

Abstract

Masked hypertension (MHT), as an independent clinical entity, its subclinical cardiac dysfunction can be early detected by left ventricular global longitudinal strain (GLS). Yet the relationship between MHT and GLS is still unclear. Therefore, we tried to conduct a community-based cross-sectional study to define this relationship. A total of 308 consecutively enrolled participants from Dongguan, China, were divided into non-hypertension (NHT) and MHT groups. Baseline characteristics were recorded, and 2-dimentional speckle-tracking echocardiography and 24-hour ambulatory blood pressure monitoring were performed. Univariate and multivariate linear regression analyses were used to assess the associations between MHT and GLS, and the dose–response curve was plotted to demonstrate their relationship. The mean age of the NHT and MHT groups was 57 and 59 years, respectively. Signs of left ventricular diastolic function, E/A (1.01 ± 0.26 vs 0.86 ± 0.23, P < 0.001) and E/e’ (8.58 ± 2.02 vs 11.70 ± 3.37, P < 0.001) were reduced in the MHT group while those of the NHT group were nearly normal. The MHT group also showed a significantly lower (‘worse’) GLS than NHT (-15.79% ± 2.81% vs -19.62% ± 1.67% vs , P < 0.001) while left ventricular ejection fraction (LVEF) did not differ between the groups. Worse GLS was independently and significantly associated with MHT both in univariate (odds ratio [OR]: 1.97, P < 0.001) and stepwise multivariate regression analysis (OR: 1.99, P < 0.001). Further analysis showed adjusted nonlinear correlation between MHT and GLS. Our study described the relationship between MHT and GLS and concluded that -14% of GLS as the cut-off value reflected MHT-associated myocardial injury before LVEF decreases.