Advantages of left atrial mechanic assessment as an additional indicator of diastolic dysfunction in patients with arterial hypertension

Abstract

Background: Arterial hypertension is the most common factor for structural and functional changes in the heart, but these changes are observed in more advanced stages and in patients with poor control of arterial hypertension. Echocardiography plays a key role in detecting these changes, but a more detailed assessment is needed to identify early changes. The role of left atrium mechanics as an additional indicator of diastolic dysfunction is still being proven, especially for patients in whom standard echocardiographic indicators are borderline and inconclusive. Aim: The aim of our study is to investigate the left atrial mechanics and the structural and functional parameters of the LC in patients with controlled arterial hypertension with a period of 5 years. Material and methods: We studied 45 consecutive middle-aged patients with mild to moderate hypertension and duration up to 5 years and 15 healthy controls. All parameters for arterial stiffness – 24-hour central systolic pressure (cSys24h), central pulse pressure (cPP24h) and 24-hour pulse wave velocity (PWV24h) were measured non – invasively with oscillometric method by Mobil-O-graph PWA. All patients underwent standard two-dimensional echocardiography with spackle tracking analysis for left ventricle (LV) and left atrium (LA) global longitudinal strain (GLS). Results: The patients with hypertension have concentric LV hypertrophy, measured by RWT (p < 0,001), reduced LV GLS (-15,83 ± 3,17 vs. -17,57 ± 2,83, p < 0,001). There is a tendency towards higher fi lling pressures E/e’m ratio (9,84 ± 2,85 vs. 7,62 ± 1,58, p = 0,006), dilated LA (LAVI: 31,86 ± 9,78 vs. 24,96 ± 4,89 ml/m2, p < 0,011) and reduced LA - GLS (29,14 ± 3,90 vs. 41,33 ± 4,37%, p < 0,0001) in comparison to control group. Strongly positive correlation is registered between PWV24h and LV concentric hypertrophy indicated as RWT (r = 0,545, p < 0,0001) There is positive correlation between cSys24h and LV concentric hypertrophy (r = 0,333, p = 0,009) and negative correlation with LA-GLS (r = -0,221, p = 0,09). E/e’ correlated positively with LAVI (r = 0,309, p = 0,016) and negatively with LA-GLS (r = 0,324, p=0,012). Multiple linear regression with multivariate models were used to estimate RWT and LA-GLS. We initially selected clinically relevant variables and known confounders for inclusion in the multivariable regression analysis, using stepwise logistic regression analysis we found that the most powerful predictors for LA-GLS are PWV24h (R = 0,459, B = -4,59, p < 0,0001) and Е/e’m: (R = 0,535, B = -291, p = 0,017). The most powerful predictor for LV hypertrophy, determine by RWT is PWV24h (R = 0,488, B = 238, p< 0,0001) and Е/e’ m (R = 0,561, B = 263, p = 0,022). Conclusion: Left atrial mechanics indicators have additional diagnostic value in assessing diastolic function, where standard indicators of diastolic function are not suffi ciently conclusive. In patients with controlled AH, early changes in the atrio-ventruculo-vascular coupling axis are observed.

Keywords

• arterial stiffness
• left ventricular hypertrophy