Evaluation of the Relationship between Circadian Blood Pressure Variation and Left Atrial Function Using Strain Imaging

Abstract

BackgroundNon-dippers were reported as showing different left atrial function, compared to dippers, but no study to date investigated the changes in the left atrial function according to the diurnal blood pressure pattern, using tissue Doppler and strain imaging.MethodsForty never treated hypertensive patients between 30 and 80 years of age were enrolled in this study. Patients were classified as non-dippers when, during night time, they had a blood pressure decrease of less than 10%. Strain of the left atrium was measured during late systole, and peak strain rates of the left atrium were measured during systole, early and late diastolic periods.ResultsThe left atrial expansion index, left atrial active emptying volume and left atrial active emptying fraction were all significantly increased in non-dippers. They also had increased values of mean peak left atrial strain (dippers = 21.26 ± 4.23% vs. non-dippers = 24.91 ± 5.20%, p = 0.02), strain rate during reservoir (dippers = 1.29 ± 0.23 s-1 vs. non-dippers =1.52 ± 0.27 s-1, p = 0.01) and contractile period (dippers = -1.38 ± 0.24 s-1 vs. non-dippers = -1.68 ± 0.32 s-1, p < 0.01).ConclusionStrain and strain rate acquired from color Doppler tissue imaging demonstrate exaggerated reservoir and booster pump function in never-treated, non-dipper hypertensive patients. These methods are simple and sensitive for the early detection of subtle changes in the left atrial function.

Comparison of Left Atrial Mechanical Function in Nondipper versus Dipper Hypertensive Patients: A Speckle Tracking Study

“…However, this is not the first study revealing the effect of dipper and nondipper status of essential hypertension in the terms of LA phasic function. In contrast to our study, Park et al 16 showed that both the reservoir and booster pump functions of the left atrium were increased in nondippers, when evaluated with strain and strain rate measured by Color Doppler tissue imaging. These findings were consistent with the results from measurements of the LA phasic volumes, as reported previously.…”

Evaluation of atrial electromechanical functions in dipper and nondipper hypertension patients using left atrial strain P‐wave dispersion and P terminal force

“…However, conventional echocardiography seems to be inadequate for detecting subclinical LA dysfunction. 21 In another study, the LA global strain and strain rates were significantly lower in an NDHT group. 17 Several studies have suggested that both the strain and strain rate are correlated inversely with age and LA diameter in healthy individuals, and the LA strain rate decreases before LA enlargement and LV hypertrophy develop in hypertensive patients.…”

“…20 A study of the LA strain and strain rate showed that the atrial reservoir and pump functions were impaired more in NDHT patients. 21 In another study, the LA global strain and strain rates were significantly lower in an NDHT group. 18 In parallel with this previous study, we observed significant differences in LA strain between dippers and nondippers, although there were no differences in tissue velocity between the two groups.…”

Nighttime blood pressure decline as a predictor of renal injury in patients with hypertension: a population-based cohort study

“…Blood pressure (BP) follows a circadian rhythm with 10–15% lower values during the night than during the day [7]. Daytime BP is more closely related to target organ damage than nighttime BP [8,9].…”