Comparison between left atrial features in well-controlled hypertensive patients and normal subjects assessed by three-dimensional speckle tracking echocardiography

Left atrial mechanics evaluated by two-dimensional strain analysis: alterations in essential hypertension

BACKGROUND

Hypertension is a cardiovascular risk factor that predisposes to cardiac structural alterations namely increased left ventricular (LV) wall thickness, reduced LV compliance and diastolic dysfunction, with consequent left atrial (LA) dilation and functional impairment. In this article, we evaluated differences in left atrial structure and function using two-dimensional speckle tracking echocardiography in patients with hypertension compared with controls.

METHODS

This was a retrospective cross-sectional study of 208 hypertensive patients and 157 controls who underwent a comprehensive transthoracic echocardiogram. Patients with hypertension were stratified by the presence of left ventricular hypertrophy (LVH).

RESULTS

Non-LVH hypertension patients had lower left atrial reservoir strain (LAS RES ) (34.78 ± 29.78 vs. 29.78 ± 6.08; P  = 0.022) and conduit strain (LAS CD ) (19.66 ± 7.29 vs. 14.23 ± 4.59; P  = 0.014) vs. controls despite similar left atrial volumes (LAV) . Left atrial contractile strain (LAS CT ) was not significantly different between non-LVH hypertension patients and controls (15.12 ± 3.77 vs. 15.56 ± 3.79; P  = 0.601). Left atrial mechanical dispersion was significantly higher in the LVH group compared with the non-LVH hypertension group (42.26 ± 13.01 vs. 50.06 ± 14.95; P  = 0.009). In multivariate regression analysis, LVH correlated with left atrial mechanical dispersion ( P  = 0.016). An age-hypertension interaction independently correlated with LAS CT ( P  < 0.001).

CONCLUSION

Hypertension results in functional left atrial changes even before development of LV hypertrophy and structural left atrial changes with increased left atrial volume. We demonstrate both a likely hypertension-associated left atrial myopathy that prevents age-related compensatory increase in left atrial contractile function, and impact of LVH in hypertension on left atrial dyssynchrony.

Associations between blood pressure levels and diabetic retinopathy in patients with diabetes mellitus: A population-based study

Purpose

To evaluate the associations of blood pressure levels with diabetic retinopathy (DR), proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME) in patients with diabetes mellitus.

Design

A cross-sectional, population-based study.

Subjects

A total of 152,844 patients with diabetes from 90 major cities in 19 provincial regions of mainland China during 2018-2021 were finally recruited.

Methods

Blood pressure was graded into 5 levels: normal (without hypertension and <120/80 mmHg), normal high (without hypertension and ≥120/80 mmHg), HT-intensive (hypertension and <120/80 mmHg), HT-moderate (hypertension and blood pressure between 120/80 mmHg and 140/90 mmHg) and HT-high (hypertension and ≥140/90 mmHg). Logistic regression was employed to verify the associations of hypertension and blood pressure levels with DR, PDR and DME. The impacts of blood pressure levels on the outcomes were qualified with nomogram models.

Main outcome measures

The main outcome was DR.

Results

There were 16,685 (10.92%) participants having DR, 2841 (1.86%) having PDR, and 1566 (1.02%) having DME. There were 8126 (5.32%) patients without hypertension and 1350 (0.88%) patients with hypertension having blood pressure <120/80 mmHg. When compared to the normal group with covariates adjusted, an increased prevalence of DR was observed in normal high (adjusted odds ratio [OR] = 1.114, 95% confidence interval [CI] = 1.033-1.202), HT-moderate (adjusted OR = 1.163, 95% CI = 1.065-1.271), and HT-high (adjusted OR = 1.203, 95% CI = 1.114-1.300).

Conclusions

There were associations between hypertension and DR, PDR, and DME in the diabetic population. Increased prevalence of DR was found with blood pressure >120/80 mmHg in both patients with and without hypertension. A nomogram was developed for DR prediction based on blood pressure levels.

Normal ranges of left atrial volumes and ejection fraction by 3D echocardiography in adults: a systematic review and meta-analysis

Increased sizes and dysfunction of the left atrium have been related to adverse outcomes. 3D-echocardiography is more accurate than 2D-echocardiography in estimating LA volumes and ejection fraction. However, the use of 3DE for LA analysis is limited by the absence of established reference values. We performed a systematic review and meta-analysis to provide reference ranges of LA maximum and minimum volumes indexed for body surface area (LAVi max and LAVi min, respectively), and LA-EF assessed by 3DE in healthy adults. Data search was conducted from inception through September 15, 2021, using the following Medical Subject Heading terms: left atrial/atrium, three-dimensional/3D echocardiography. The study protocol was registered in the PROSPERO database (CRD42021252428). 15 studies including 4,226 healthy adults (51% males) and reporting 3DE values of LAVi max, LAVi min and LA-EF were selected. LAVi max, LAVi min and LA-EF mean and reference values were equal to 25.18 ml/m2 (95% CI 23.10, 27.26), 11.10 ml/m2 (10.01, 12.18) and 55.94% (51.92, 59.96), respectively. No influential studies were identified. Pooled estimates per age group- and sex were also estimated. By meta-regression analyses, we identified variability in LA volumes and LA-EF depending on participants' age, ethnicity and number of heart cycles at 3D multi-beat acquisition. At individual patient data analysis conducted on 374 subjects, a software effect on LA-EF was shown. This systematic review and meta-analysis provides reference values of LAVi max, LAVi min and LA-EF assessed by 3DE in healthy adults, encouraging 3DE evaluation of the LA evaluation in daily practice.

Left atrial phasic function remodeling during its enlargement: a two-dimensional speckle-tracking echocardiography study

BACKGROUND

Left atrial (LA) size is often used as a surrogate marker of LA function in clinical practice, with larger atrial thought to represent a "dysfunctioning" atrium, since there is no accepted 'gold' standard to evaluate LA function. The exact relationship between LA size and phasic function, and whether LA dysfunction occur before LA enlargement (LAE) may be of clinical interest while have not been fully studied. Two-dimensional speckle-tracking echocardiography (2D STE) was showed a promising method in measuring LA physical deformation.

MATERIALS AND METHODS

A community cohort of 715 subjects at cardiovascular disease high risk accepted comprehensive echocardiography. LA longitudinal phasic strain Sa (absolute peak strain during atrial contraction), Se (peak strain at early diastole) and Stot (total atrial strain = Sa + Se), representing contractile, conduit, and reservoir function respectively, were measured using off-line 2D STE software in apical 4 chamber view, and data were compared among groups at different LA size and between subgroups in normal LA size with and without hypertension (HT).

RESULTS

With LAE (from normal size, mild, moderate to severe LAE), the Stot (21.74 ± 5.97, 20.75 ± 4.99, 20.49 ± 5.27, 17.75 ± 4.71, respectively, ANOVA P = 0.003) and Sa (11.84 ± 3.92, 11.00 ± 3.29, 10.11 ± 2.57, 8.55 ± 2.88, respectively, ANOVA P < 0.001) reduced while Se had no change. Stot of Severe LAE group was significantly lower than that of Normal LA size group (P = 0.002). Sa of the three LAE groups were all significantly lower than that of Normal LA size group (P = 0.024, P = 0.002, P < 0.001, respectively). In normal sized LA subgroups, Stot (21.35 ± 5.91 vs. 23.01 ± 6.02, P = 0.008) and Se (9.51 ± 4.41 vs. 11.17 ± 4.89, P < 0.001) reduced in subjects with HT comparing with those without.

CONCLUSION

LA phasic function remodeling occurs before LAE and continues with LAE, with reservoir, conduit and contractile function being affected unparalleled.

Relationships among pulmonary capillary wedge pressure, dry weight and natriuretic peptide in patients undergoing hemodialysis: a three-dimensional speckle tracking echocardiography study

BACKGROUND

Although the evaluation of fluid status in hemodialysis (HD) patients is useful, relationship among pulmonary capillary wedge pressure (PCWP), dry body weight (DW) and natriuretic peptide has not been elucidated. In addition, there has been no objective marker for instantaneously monitoring hemodynamic improvement in response to HD. We previously reported that PCWP and time constant of left ventricular pressure decline (Tau) can be noninvasively estimated (ePCWP and eTau) by speckle tracking echocardiography (STE). The aim of this study was to elucidate the relationship among ePCWP, eTau, DW and natriuretic peptide in patients undergoing HD.

METHODS

We measured ePCWP and body weight (BW) by STE in 81 patients and ANP and BNP by blood examination in 31 patients just before and after HD during sinus rhythm.

RESULTS

The ePCWP decreased after HD, and this was associated with reductions in ln ANP, eTau and BW (r = 0.523, 0.271 and 0.814, respectively, p < 0.05). The % change in ePCWP was not correlated with the % change in ln BNP (p = 0.47). The change in ePCWP had a stronger correlation with the % change in BW than the change in any other parameters.

CONCLUSIONS

The ePCWP is more sensitive to estimate the change in BW during HD than any other parameters such as ANP and BNP. These results indicated that a substantial amount of excess fluid can be assessed real-time by STE using ePCWP.

Improving performance of 3D speckle tracking in arterial hypertension and paroxysmal atrial fibrillation by using novel strain parameters

The function of left atrium (LA) is closely related to LA remodeling and one of the most important mechanisms is an increased deposition of fibrous tissue that often is the basis for LA electro-mechanical changes before the onset of atrial fibrillation (AF). This study evaluated LA shape and function, by investigating standard and novel strain parameters calculated by a new approach based on homologous times derived from 3D speckle tracking echocardiography (3DSTE) in hypertensive (HT) and paroxysmal atrial fibrillation (PAF) patients with or without left ventricular hypertrophy (LVH), compared to control (C) subjects. LA function was assessed using homologous times to compare strain variables among different individuals, acquired at different physiological time periods. Standard global longitudinal (GLS) and circumferential (GCS) strains were measured at peak of atrial diastole, while longitudinal and circumferential strains (GLSh, GCSh), strain rate (GLSr, GCSr), volume (Vh) and volume rate (Vr) were measured during the atrial telediastolic phase (fifth homologous time) and atrial pre-active phase (tenth homologous time). Using ANOVA, we found an impaired LA deformation detected by standard, interpolated strains and strain rates in both HT and PAF groups compared to C. We also performed ROC analysis to identify different performances of each parameter to discriminate groups (GLSr10 + GCSr10: C vs PAF 0.935; C vs PAF_LVH 0.924; C vs HT_LVH 0.844; C vs HT 0.756). Our study showed anatomical and functional LA remodeling in patients with PAF and HT. 3D strains and strain rates derived from the homologous times approach provide more functional information with improved performance to identify among the explored groups, in particular PAF patients.

Reliability of echocardiographic speckle-tracking derived bi-atrial strain assessment under different hemodynamic conditions

The aim of this study was to assess intra- and inter-observer variability of left (LA) and right atrial (RA) strain indices obtained by two-dimensional speckle-tracking echocardiography (2D-STE) in a healthy group of individuals at low-altitude and after rapid ascent to high-altitude in order to provoke altered systemic and pulmonary hemodynamics otherwise seen in various cardiac diseases. Twenty healthy subjects underwent transthoracic echocardiography during a baseline examination at low-altitude (424 m) as well as 7, 20 and 44 h after arrival at high-altitude (4559 m). Atrial strain indices (i.e. reservoir, conduit and contractile strain) were determined off-line by two independent observers. Intra- and inter-observer reproducibility of variables was assessed by intra-class correlation coefficients (ICCs), coefficients of variation and Bland Altman plots. Heart rate, systemic blood pressure and pulmonary artery pressure increased significantly from low-altitude to the first examination at high-altitude. Intra-observer ICCs were ≥0.90 except for RA conduit strain with an ICC of 0.86. The mean intra-observer differences were small and limits of agreement of relative differences were narrow for all atrial strain parameters (<3 and <16%, respectively). Inter-observer ICCs (0.80-0.90), mean biases and limits of agreement (<4 and <20%, respectively) were greater than intra-observer results for all parameters. Intra- and inter-obserer ICCs for all atrial strain variables did not differ between low- and high-altitude. 2D-STE-derived bi-atrial strain indices have excellent intra- and moderate inter-observer reproducibility with no effect of high-altitude-induced hemodynamic changes on reliability results.

Impact of gender and healthy aging on pulmonary capillary wedge pressure estimated by the kinetics-tracking index using two-dimensional speckle tracking echocardiography

Risk stratification in heart failure (HF) among patients and healthy subjects using pulmonary capillary wedge pressure (PCWP) is important for understanding when and why HF develops. The aim of the present study was to evaluate the impact of gender and healthy aging on estimated PCWP using a kinetics-tracking index in patients and in healthy subjects without hypertension. The study population consisted of 198 healthy subjects without cardiovascular or other systemic diseases and who were not taking any medications. Echocardiographic studies were performed using an ACUSON Sequoia 512 ultrasound system. Active left atrial (LA) emptying function (EF) was defined as (pre-atrial contraction LA volume-minimum LA volume)/pre-atrial contraction LA volume × 100%. With an increase in age, the E/A and E/e' ratios (markers of left ventricular (LV) diastolic dysfunction (DD)) showed a similar decrease in males and females. PCWP was maintained at 8.3±1.8 mm Hg in males and 8.2±2.3 mm Hg in females because of compensation by an increase in active LA EF. In contrast, the compensation for LV DD with an increase in active LA EF in females tended to be more gradual (slope=0.11) than in males (slope=0.18, P=0.060 vs. female). The parameters that indicated LV DD deteriorated with advancing age. PCWP might be maintained because of compensation, namely an increase in active LA EF in both males and females. The compensation in female septuagenarians and octogenarians was weaker than in male septuagenarians and octogenarians. This difference in compensation may explain why HF with preserved LV ejection fraction occurs more frequently in females than in males.

A novel ultrasound predictor of pulmonary capillary wedge pressure assessed by the combination of left atrial volume and function: A speckle tracking echocardiography study

BACKGROUND

We hypothesized that a development of a novel index based on the combination of left atrial volume (LAV) and left atrial (LA) function evaluated by the time-LA volume curve using speckle tracking echocardiography (STE) would be accurate and useful to estimate pulmonary capillary wedge pressure (PCWP). Our goal was to develop a novel index of PCWP based on a combination of LAV and LA function using STE.

METHODS

A cross-validation study was performed with the patients divided into a training study to define the novel index (n=50) and a testing study to validate the index (n=196). PCWP was measured by right heart catheterization, and phasic LAV and emptying function (EF) were measured by STE.

RESULTS

Simple linear regression analysis in the training study revealed that the novel index that best estimated PCWP was the kinetics-tracking index [KT index=log10 (active LAEF/minimum LAV index)]. Multiple regression analysis revealed that the KT index was the most reliable predictor of PCWP. It had the strongest correlation with PCWP (r=-0.86, p<0.001) among all echocardiographic parameters. In the testing study, PCWP estimated by the KT index was also strongly correlated with measured PCWP (r=0.92, p<0.001). These correlations were also strong in the patients with reduced left ventricular ejection fraction (<50%), chronic heart failure, and chronic atrial fibrillation (r=0.92, r=0.91, r=0.79, p<0.001, respectively).

CONCLUSIONS

A novel index (KT index) using a combination of LAV and LA function was a powerful and useful predictor of PCWP and may be valuable in routine clinical practice.