Speckle Tracking Echocardiography in the Diagnosis of Subclinical Left Ventricular Systolic Dysfunction in Hypertensive Patients

摘要

The early diagnosis of subclinical left ventricular systolic dysfunction in hypertensive patients is of crucial importance to prevent further adverse events and the onset of tissue and organ complications.Aim: To determine a high-risk group on the basis of subclinical Left Ventricular (LV) systolic dysfunction using Speckle Tracking Echocardiography (STE).Materials and Methods: This was a case-control study comparing 80 patients with hypertension (HTN, mild, moderate and severe) with preserved Ejection Fraction (EF) with or without Diastolic Dysfunction (DD) to 70 healthy volunteers. We defined subclinical LV systolic dysfunction as a reduced global longitudinal strain (GLS) <-20%, determined by Two Dimensional-STE (2D-STE). The statistical analysis was performed using unpaired t-test to assess categorical data, chisquare test for proportions, Pearson?s coefficient for strength of correlation and multiple regressions for continuous variables and their association with age and gender. Inter-and intraobserver variability were assessed using intraclass correlation coefficient. The significance level was set at p<0.05.Results: Significant differences in EF between HTN and the controls were not found. The GLS showed normal values in the controls and non-significant changes in patients with mild HTN without DD (p=0.840). A stepwise reduction of the GLS, which is dependent on the severity of HTN and DD was observed. The more severe the HTN and DD respectively, the more significant was the reduction of the GLS (p<0.001). In patients with HTN and reduced GLS, increased Body Mass Index (BMI) (p<0.001), Left Atrial Volume Index (LAVI) (p<0.001) and Left Ventricular Mass Index (LVMI) (p<0.001), reduced Sm (p=0.01) and Mitral Annular Plane Systolic Excursion (MAPSE) (p=0.02) were found. A moderate negative correlation between GLS and BMI (r=- 0.52; p<0.001) as well as GLS and LVMI (r=-0.61; p<0.001) were observed. A moderate positive correlation between GLS and EF (r=0.48; p=0.03), and GLS and Sm (r=0.56; p=0.01), as well as strong positive correlation between GLS and MAPSE were also found (r=0.756; p=0.003). These findings were observed mainly in patients with HTN and DD.Conclusion: The 2D-STE GLS provides an excellent opportunity for an early diagnosis of the subclinical LV systolic dysfunction in patients with HTN. In contrast to EF, GLS gives the real concept for the minimal changes in LV longitudinal mechanics, mainly in subjects with already developed DD. These findings corresponded to a higher risk of adverse CV events, and give a strong evidence to augment the antihypertensive treatment, control of the risk factors and lifestyle changes.