The influence of white-coat hypertension on left atrial phasic function

Phenotyping the hypertensive heart

Arterial hypertension remains the most frequent cardiovascular (CV) risk factor, and is responsible for a huge global burden of disease. Echocardiography is the first-line imaging method for the evaluation of cardiac damage in hypertensive patients and novel techniques, such as 2D and D speckle tracking and myocardial work, provide insight in subclinical left ventricular (LV) impairment that would not be possible to detect with conventional echocardiography. The structural, functional, and mechanical cardiac remodelling that are detected with imaging are intermediate stages in the genesis of CV events, and initiation or intensification of antihypertensive therapy in response to these findings may prevent or delay progressive remodelling and CV events. However, LV remodelling—especially LV hypertrophy—is not specific to hypertensive heart disease (HHD) and there are circumstances when other causes of hypertrophy such as athlete heart, aortic stenosis, or different cardiomyopathies need exclusion. Tissue characterization obtained by LV strain, cardiac magnetic resonance, or computed tomography might significantly help in the distinction of different LV phenotypes, as well as being sensitive to subclinical disease. Selective use of multimodality imaging may therefore improve the detection of HHD and guide treatment to avoid disease progression. The current review summarizes the advanced imaging tests that provide morphological and functional data about the hypertensive cardiac injury.

Age impacts left atrial functional remodeling in athletes

Aim

Age-associated changes in cardiac filling and function are well known in the general population. Yet, the effect of aging on left atrial (LA) function, and its interaction with left ventricular (LV) adaptation, remain less described when combined with high-intensity chronic training. We aimed to analyze the effects of aging on LA and LV functions in trained athletes.

Methods and results

Ninety-five healthy highly-trained athletes referred for resting echocardiography were included. Two groups of athletes were retrospectively defined based on age: young athletes aged <35 years (n = 54), and master athletes aged ≥35 years (n = 41). All subjects were questioned about their sports practice. Echocardiographic analysis of LV systolic and diastolic functions (2D-echo, 3D-echo, and Doppler), as well as LA 2D dimensions and phasic deformations assessed by speckle tracking, were analyzed. Master athletes (mean age = 46.3 ± 8.3 years, mean duration of sustained training = 13.7 ± 8.9 years) exhibited significantly stiffer LV and LA with reduced LV early diastolic functional parameters (ratio E/A, peak e’, and ratio e’/a’), LA reservoir and conduit strain, whereas LA volume, LA contractile strain and LV peak a’ were higher, compared to young athletes. Multivariate regression analysis confirmed that age was predictive of peak e’, LA reservoir strain and LA conduit strain, independently of training variables. LA phasic strains were strongly associated with LV diastolic function.

Conclusions

Regardless of chronic sports practice, master athletes exhibited age-related changes in LA function closely coupled to LV diastolic properties, which led to LV filling shifts to late diastole.

Clinical implication of disturbed left atrial phasic functions in the heterogeneous population associated with hypertension or atrial fibrillation

BACKGROUND

To evaluate left atrial (LA) phasic functions in patients with hypertension and/or paroxysmal atrial fibrillation (PAF) and its clinical significance.

METHODS

LA strain was studied in 77 patients (25 hypertension, 24 lone AF, and 28 with both hypertension and PAF) and 28 controls using two-dimensional speckle-tracking echocardiography (2D STE). The following indexes during atrial reservoir, conduit and pump phase were analyzed respectively: (1) peak atrial longitudinal strain (PALS) and strain rate (PALSR), (2) the standard deviation of time to PALS and PALSR of all LA segments (TpS-SD% and TpSR-SD%).

RESULTS

Compared with controls, PALS_res, PALS_cond and PALSR_cond were significantly reduced in patients with isolated hypertension (all P < 0.01) but no significant differences were observed in PALS_pump, PALSR_pump and TpS_pump-SD% between them (all P > 0.05). PALS_pump, PALSR_pump and PALSR_res were significantly lower in patients with both hypertension and PAF than in those with isolated hypertension (all P < 0.05). PALS and PALSR were significantly decreased, and TpS-SD% was significantly increased during each phase in lone AF patients than in controls (all P < 0.05), and PALSR_pump was further depressed in patients with both hypertension and PAF (P = 0.029). PALSR_cond ≤ 1.475 s^- 1 combined with TpS_pump-SD% ≥ 3.25% (sensitivity, 85%; specificity, 71%; AUC = 0.845, P < 0.001) could distinguish lone AF from healthy subjects effectively, while in hypertensive patients, PALS_pump ≤ 14.2% was found to be an independent differentiator for occurrence of AF or not with sensitivity of 81% and specificity of 84% (AUC = 0.838, P < 0.001). LAVI≥29.3 mL/m² was an independent characteristic for reflecting different LA remodeling in lone AF or hypertension with AF.

CONCLUSIONS

The impairment of LA phasic functions was varied in patients with hypertension and/or AF. The disturbed LA phasic functions were proved to have independent abilities of differential diagnosis in this heterogeneous population associated with hypertension or AF.

Cumulative blood pressure from early adulthood to middle age is associated with left atrial remodelling and subclinical dysfunction assessed by three-dimensional echocardiography: a prospective post hoc analysis from the coronary artery risk development in young adults study

Aims

To evaluate the association of cumulative blood pressure (BP) from young adulthood to middle age with left atrial (LA) structure/function as assessed by three-dimensional echocardiography (3DE) in a large longitudinal bi-racial population study.

Methods and results

We conducted a prospective post hoc analysis of individuals enrolled at the Coronary Artery Risk Development in Young Adults, which is a multi-centre bi-racial cohort with 30 years of follow-up. Cumulative systolic and diastolic BP levels were defined by summing the product of average millimetres of mercury and the years between each two consecutive clinic visits over 30 years of follow-up. Multivariable linear regression analyses were used to assess the relationship between cumulative systolic and diastolic BP with 3DE LA structure and function, adjusting for demographics and traditional cardiovascular risk factors. A total of 1033 participants were included, mean age was 55.4 ± 3.5 years, 55.2% women, 43.9% blacks. Cumulative systolic BP had stronger correlations than cumulative diastolic BP. Higher cumulative systolic BP was independently associated with higher 3D LA volumes: maximum (β = 1.74, P = 0.004), pre-atrial contraction (β = 1.87, P < 0.001), minimum (β = 0.76, P = 0.04), total emptying (β = 0.98, P = 0.006), active emptying (β = 1.12, P < 0.001), and lower magnitude 3D LA early diastolic strain rate (β = 0.05, P = 0.02). Higher cumulative diastolic BP was independently associated with higher 3D LA active emptying volume (β = 0.66, P = 0.002), lower magnitude 3D LA early diastolic strain rate (β = 0.05, P = 0.004), and higher magnitude 3D LA late diastolic strain rate (β = -0.04, P = 0.05).

Conclusion

Higher cumulative BP from early adulthood throughout middle age was associated with adverse LA remodelling evaluated by 3D echocardiography.

The importance of integrated left atrial evaluation: From hypertension to heart failure with preserved ejection fraction

AIM

Functional analysis and measurement of left atrium are an integral part of cardiac evaluation, and they represent a key element during non-invasive analysis of diastolic function in patients with hypertension (HT) and/or heart failure with preserved ejection fraction (HFpEF). However, diastolic dysfunction remains quite elusive regarding classification, and atrial size and function are two key factors for left ventricular (LV) filling evaluation. Chronic left atrial (LA) remodelling is the final step of chronic intra-cavitary pressure overload, and it accompanies increased neurohormonal, proarrhythmic and prothrombotic activities. In this systematic review, we aim to purpose a multi-modality approach for LA geometry and function analysis, which integrates diastolic flow with LA characteristics and remodelling through application of both traditional and new diagnostic tools.

METHODS

The most important studies published in the literature on LA size, function and diastolic dysfunction in patients with HFpEF, HT and/or atrial fibrillation (AF) are considered and discussed.

RESULTS

In HFpEF and HT, pulsed and tissue Doppler assessments are useful tools to estimate LV filling pressure, atrio-ventricular coupling and LV relaxation but they need to be enriched with LA evaluation in terms of morphology and function. An integrated evaluation should be also applied to patients with a high arrhythmic risk, in whom eccentric LA remodelling and higher LA stiffness are associated with a greater AF risk.

CONCLUSION

Evaluation of LA size, volume, function and structure are mandatory in the management of patients with HT, HFpEF and AF. A multi-modality approach could provide additional information, identifying subjects with more severe LA remodelling. Left atrium assessment deserves an accurate study inside the cardiac imaging approach and optimised measurement with established cut-offs need to be better recognised through multicenter studies.