Beta-Blocker Use Is Associated With Impaired Left Atrial Function in Hypertension

MRI Assessment of Diastolic Dysfunction in People Living With the Human Immunodeficiency Virus: Correlation With Markers of Disease Activity

BACKGROUND

Despite the advent of combination antiretroviral therapy, people living with human immunodeficiency virus (PLWH) are at an increased risk for cardiac disease.

PURPOSE

To explore the presence and extent of diastolic atrial and left ventricular dysfunction in PLWH using cardiac MRI in correlation with clinical markers of disease activity.

STUDY TYPE

Prospective.

POPULATION

A total of 163 participants comprising 101 HIV-infected individuals (age: 52 years [42-62 years]; 92% male) and 62 age- and sex-matched healthy volunteers (age: 51 years [30-72 years]; 85% male).

FIELD STRENGTH/SEQUENCE

3.0 T, cardiac MRI including balanced steady-state free precession (SSFP) for the short-axis, two-, three-, and four-chamber views were performed.

ASSESSMENT

Assessment of cardiac function and strain analysis were accomplished by CVI42 software. Blood samples for CD4+ T cells and cardiac risk factors were also collected before MRI.

STATISTICAL TESTS

Independent t tests, Mann-Whitney U test, Pearson's correlation analysis, and multivariate linear analyses (significance level: P < 0.05).

RESULTS

PLWH had a significantly larger left atrial volume maximum index (LAVImax: 32.6 ± 8.7 vs. 28.7 ± 8.1 mL/m2), minimum (LAVImin: 14.8 ± 5.5 vs. 11.5 ± 5.4 mL/m2,), and prior to atrial contraction (LAVIpre-a: 23.4 ± 6.7 vs. 19.7 ± 7.2 mL/m2) as compared to healthy volunteers. The LA reservoir (LAtEF: 55.0 ± 10.2 vs. 61.4 ± 10.4; Sls: 29.0 ± 8.1 vs. 33.8 ± 11.8), conduit (LApEF: 28.4 ± 8.2 vs. 32.3 ± 11.3, P = 0.01; Sle: 16.3 ± 6.5 vs. 18.9 ± 8.2), and booster pump function (LAaEF: 37.4 ± 12.4 vs. 42.7 ± 13.1, P = 0.01, Sla: 12.7 ± 5.1 vs. 14.9 ± 5.7) were all significant impaired in PLWH. Global circumferential left ventricular diastolic strain rate (LVGCS-d) was significantly lower in the HIV patients. Multivariate analysis results showed that Nadir CD4+ T cells had a significant adverse association with LVGCS-d (β = 0.51).

CONCLUSION

LA structure abnormalities and LV diastolic dysfunction were manifested in PLWH, with Nadir CD4+ T cell counts potentially serving as a risk factor for early cardiac diastolic dysfunction.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.

Association between types of antihypertensive medication and the risk of atrial fibrillation: a nationwide population study

Background

Patients with hypertension are at a high risk of atrial fibrillation (AF). Recent research has indicated the varying effects of antihypertensive medications on developing AF.

Objectives

We investigated the relationship between different types of antihypertensive medications and the risk of AF occurrence.

Methods

We analyzed data from 113,582 subjects with national health screening examinations between 2009 and 2014. The study population was categorized according to antihypertensive medication type. The primary outcome was the incidence of AF.

Results

Among 113,582 subjects (mean age 59.4 ± 12.0 years, 46.7% men), 93,557 received monotherapy [angiotensin receptor blockers (ARB), angiotensin-converting enzyme inhibitors (ACEi), beta-blockers, calcium channel blockers (CCB), or diuretics], while 34,590 received combination therapy (ARB/beta-blockers, ARB/CCB, ARB/diuretics, or ARB/CCB/diuretics). During a mean follow-up duration of 7.6 ± 2.1 years, 3.9% of patients were newly diagnosed with AF. In monotherapy, ACEi and CCB had similar AF risks as ARB, while beta-blockers and diuretics showed higher AF risks than ARB. In combination therapy, ARBs/CCBs and ARBs/diuretics had the lowest AF risk, whereas ARBs/beta-blockers had the highest compared to ARB/CCB. Among the specific ARBs, the AF risk varied insignificantly, except for telmisartan and candesartan.

Conclusions

In hypertensive patients receiving monotherapy, ACEi and CCB showed a similar AF risk as ARBs, while beta-blockers and diuretics were associated with a higher risk. Among those receiving combination therapy, ARBs/CCBs and ARBs/diuretics had the lowest AF risk, whereas ARBs/beta-blockers showed the highest risk. Various types of ARBs have different associations with AF risk.

Beta-blockers in Hypertensive Left Ventricular Hypertrophy and Atrial Fibrillation Prevention

BACKGROUND

Hypertensive left ventricular hypertrophy (HTN LVH) is a key risk factor for atrial fibrillation (AF).

OBJECTIVE

To evaluate the possible role of beta-blockers (BBs) in addition to a renin-angiotensinaldosterone system (RAAS) blocker in AF prevention in patients with HTN LVH.

METHODS

We performed a PubMed, Elsevier, SAGE, Oxford, and Google Scholar search with the search items 'beta blocker hypertension left ventricular hypertrophy patient' from 2013-2023. In the end, a 'snowball search', based on the references of relevant papers as well as from papers that cited them was performed.

RESULTS

HTN LVH is a risk factor for AF. In turn, AF substantially complicates HTN LVH and contributes to the genesis of heart failure (HF) with preserved ejection fraction (HFpEF). The prognosis of HFpEF is comparable with that of HF with reduced EF (HFrEF), and, regardless of the type, HF is associated with five-year mortality of 50-75%. The antiarrhythmic properties of BBs are wellrecognized, and BBs as a class of drugs are - in general - recommended to decrease the incidence of AF in HTN.

CONCLUSION

BBs are recommended (as a class) for AF prevention in several contemporary guidelines for HTN. LVH regression in HTN - used as a single criterion for the choice of antihypertensive medication - does not capture this protective effect. Consequently, it is worth studying how meaningful this antiarrhythmic action (to prevent AF) of BBs is in patients with HTN LVH in addition to a RAAS blocker.

Subclinical Dysfunction of Left Atrial Compliance after Cryoballoon versus Radiofrequency Ablation for Paroxysmal Atrial Fibrillation

It has been suggested that cryoballoon (CB) ablation for paroxysmal atrial fibrillation (PAF) may lead to more extensive left atrial (LA) injury than radiofrequency (RF) ablation; however, results are conflicting. We sought to address this issue using modern echocardiographic techniques estimating the LA function after successful CB and RF ablation for PAF. A total of 90 patients (66% males, mean age 57 ± 10 years) successfully treated (no AF recurrences confirmed in serial 4-7 day ECG Holter monitoring) with RF (51%) or CB (49%) ablation for PAF were retrospectively studied. Echocardiography with speckle tracking (STE) was performed before and 12 months after the procedure. The peak longitudinal LA strain (LAS) and strain rate (LASR) during the reservoir (r), conduit (cd), and contraction (ct) phases were measured in sinus rhythm. Analysis of covariance was applied to compare changes in the echocardiographic parameters over time with the baseline measurements as covariance and the type of ablation as the factor. The parallelism of the slopes of the covariance was tested. The LA diameter decreased (38.3 ± 4.1 mm vs. 36.8 ± 3.6 mm, p < 0.001) in the whole study group at 12 months after ablation. The LASRr and LASRcd increased (1.1 ± 0.3 s-¹ vs. 1.3 ± 0.3 s-¹, p < 0.001 and 1.1 ± 0.3 s-¹ vs. 1.2 ± 0.3 s-¹, p < 0.001, respectively) whereas other LA strain parameters remained unchanged in the whole study group at 12 months after ablation. In the analysis of LA function at 12 months after the procedure regarding the mode of ablation, the worsening of parameters reflecting LA compliance was observed in patients with better pre-served baseline values in the CB ablation subgroup. For baseline LAScd >28%, the difference ΔCB - ΔRF was -7.6 (11.7; -3.4), p < 0.001, and for baseline LAScd >16%, ΔCB - ΔRF was -1.8 (-3.2; -0.4), p = 0.014. The traditional Doppler-derived parameter e' showed the same trend-for baseline e' ≥12 cm/s, ΔCB - ΔRF was -1.7 (-2.8; -0.6), p = 0.003. We conclude that worsening of parameters reflecting LA compliance was observed 12 months after CB ablation compared to RF ablation for PAF in patients who underwent a successful procedure and had better-preserved baseline LA function. This might suggest subclinical dysfunction of LA after the CB ablation procedure. The clinical significance of these findings warrants further investigations.

Lower heart rates and beta-blockers are associated with new-onset atrial fibrillation

Background

Lower heart rates (HRs) prolong diastole, which increases filling pressures and wall stress. As a result, lower HRs may be associated with higher brain natriuretic peptide (BNP) levels and incident atrial fibrillation (AF). Beta-blockers may increase the risk for AF due to suppression of resting HRs.

Objective

Examine the relationships of HR, BNP, beta-blockers and new-onset AF in the REVEAL-AF and SPRINT cohort of subjects at risk for developing AF.

Methods

In REVEAL-AF, 383 subjects without a history of AF and a mean CHA₂DS₂VASC score of 4.4 ± 1.3 received an insertable cardiac monitor and were followed up to 30 months. In SPRINT, 7595 patients without prior history of AF and a mean CHA₂DS₂VASC score of 2.3 ± 1.2 were followed up to 60 months.

Results

The median daytime HR in the REVEAL-AF cohort was 75bpm [IQR 68-83]. Subjects with below-median HRs had 2.4-fold higher BNP levels compared to subjects with above-median HRs (median BNP [IQR]: 62 pg/dl [37-112] vs. 26 pg/dl [13-53], p < 0.001). HRs <75bpm were associated with a higher incidence of AF: 37% vs. 27%, p < 0.05. This was validated in the SPRINT cohort after adjusting for AF risk factors. Both a HR < 75bpm and beta-blocker use were associated with a higher rate of AF: 1.9 vs 0.7% (p < 0.001) and 2.5% vs. 0.6% (p < 0.001), respectively. The hazard ratio for patients on beta-blockers to develop AF was 3.72 [CI 2.32, 5.96], p < 0.001.

Conclusions

Lower HRs are associated with higher BNP levels and incident AF, mimicking the hemodynamic effects of diastolic dysfunction. Suppression of resting HR by beta-blockers could explain their association with incident AF.

Association of Left Atrial Strain With Ischemic Stroke Risk in Older Adults

Importance

The risk of ischemic stroke is higher among patients with left atrial (LA) enlargement. Left atrial strain (LAε) and LA strain rate (LASR) may indicate LA dysfunction when LA volumes are still normal. The association of LAε with incident ischemic stroke in the general population is not well established.

Objective

To investigate whether LAε and LASR are associated with new-onset ischemic stroke among older adults.

Design

The Cardiovascular Abnormalities and Brain Lesions study was conducted from September 29, 2005, to July 6, 2010, to investigate cardiovascular factors associated with subclinical cerebrovascular disease. A total of 806 participants in the Northern Manhattan Study who were aged 55 years or older without history of prior stroke or atrial fibrillation (AF) were included, and annual follow-up telephone interviews were completed May 22, 2022. Statistical analysis was performed from June through November 2022.

Exposures

Left atrial strain and LASR were assessed by speckle-tracking echocardiography. Global peak positive longitudinal LAε and positive longitudinal LASR during ventricular systole, global peak negative longitudinal LASR during early ventricular diastole, and global peak negative longitudinal LASR during LA contraction were measured. Brain magnetic resonance imaging was used to detect silent brain infarcts and white matter hyperintensities at baseline.

Main Outcomes and Measures

Risk analysis with cause-specific Cox proportional hazards regression modeling was used to assess the association of positive longitudinal LAε and positive longitudinal LASR with incident ischemic stroke, adjusting for other stroke risk factors, including incident AF.

Results

The study included 806 participants (501 women [62.2%]) with a mean (SD) age of 71.0 (9.2) years; 119 participants (14.8%) were Black, 567 (70.3%) were Hispanic, and 105 (13.0%) were White. During a mean (SD) follow-up of 10.9 (3.7) years, new-onset ischemic stroke occurred in 53 participants (6.6%); incident AF was observed in 103 participants (12.8%). Compared with individuals who did not develop ischemic stroke, participants with ischemic stroke had lower positive longitudinal LAε and negative longitudinal LASR at baseline. In multivariable analysis, the lowest (ie, closest to zero) vs all other quintiles of positive longitudinal LAε (adjusted hazard ratio [HR], 3.12; 95% CI, 1.56-6.24) and negative longitudinal LASR during LA contraction (HR, 2.89; 95% CI, 1.44-5.80) were associated with incident ischemic stroke, independent of left ventricular global longitudinal strain and incident AF. Among participants with a normal LA size, the lowest vs all other quintiles of positive longitudinal LAε (HR, 4.64; 95% CI, 1.55-13.89) and negative longitudinal LASR during LA contraction (HR, 11.02; 95% CI 3.51-34.62) remained independently associated with incident ischemic stroke.

Conclusions and Relevance

This cohort study suggests that reduced positive longitudinal LAε and negative longitudinal LASR are independently associated with ischemic stroke in older adults. Assessment of LAε and LASR by speckle-tracking echocardiography may improve stroke risk stratification in elderly individuals.

Decreased left atrial function in obesity patients without known cardiovascular disease

Obesity is a risk factor for heart failure with preserved ejection fraction (HFpEF). We hypothesized that assessment of left atrial (LA) strain may be useful to reveal precursors of HFpEF in obesity patients. Echocardiograms of obesity patients without known cardiovascular disease who underwent bariatric surgery, and echocardiograms of age- and gender matched controls were analyzed. The echocardiogram was repeated 1 year after bariatric surgery. LA reservoir strain (LASr), LA conduit strain (LAScd), and LA contractile strain (LASct) were measured. 77 Obesity patients were compared with 46 non-obese controls. Obesity patients showed a significantly decreased LA function compared with non-obese individuals (LASr 32.2% ± 8.8% vs. 39.6% ± 10.8%, p < 0.001; LAScd 20.1% ± 7.5% vs. 24.9% ± 8.3%, p = 0.001; LASct 12.1% ± 3.6% vs. 14.5% ± 5.5%, p = 0.005). There was no difference in prevalence of diastolic dysfunction between the obesity group and controls (9.1% vs. 2.2%, p = 0.139). One year after bariatric surgery, LASr improved (32.1% ± 8.9% vs. 34.2% ± 8.7%, p = 0.048). In the multivariable linear regression analysis, BMI was associated with LASr, LAScd, and LASct (β =  - 0.34, CI - 0.54 to - 0.13; β =  - 0.22, CI - 0.38 to - 0.06; β =  - 0.10, CI - 0.20 to - 0.004). Obesity patients without known cardiovascular disease have impairment in all phases of LA function. LA dysfunction in obesity may be an early sign of cardiac disease and may be a predictor for developing HFpEF. LASr improved 1 year after bariatric surgery, indicating potential reversibility of LA function in obesity.

The impact of medical therapy on left ventricular strain: Current state and future perspectives

The speckle tracking strain is becoming a frequently used marker of subclinical left ventricular systolic dysfunction. Despite the wide range of data concerning left ventricular strain variability in the general population and its changes in various pathologic conditions, the information about the impact of medical therapy on left ventricle strain is limited. This article provides an analysis of published studies of left ventricle strain changes in response to different agents and combinations of medical therapies used for hypertension and congestive heart failure.

The genetics of cardiac failure: Role of a G protein-coupled receptor polymorphism in therapeutic response in an Indian population

BACKGROUND AND AIM

The incidence of heart failure (HF) is rising to epidemic proportions in developing countries like India. A lack of adequate Indian studies underscores the importance of pursuing research into HF in an Indian population. G protein-coupled receptor kinase 5 (GRK5) Gln41>Leu (rs2230345) polymorphism was reported as a genetic modifier associated with survival in HF patients. A prospective study was conducted to investigate the association of GRK5 Gln41>Leu polymorphism with response to β-blocker therapy in Indian HF patients.

METHODS

HF patients (n=584) were recruited for the study. The patients were genotyped by tetra-primer based allele specific polymerase chain reaction and confirmed with Sanger sequencing. The HF patients were evaluated for GRK5 gene expression and followed up for ~3 years. Drug dosages, cardiac output and hospitalization-free survival were evaluated as study outcomes. HF subgroups (i.e. systolic or diastolic dysfunction, biventricular dysfunction and pulmonary artery hypertension) were also analyzed in association with hospital-free survival.

RESULTS

HF patients showed genotype frequencies of AT (15%) and TT (1%). AT/TT genotype carriers showed downregulated GRK5 gene expression and significant reduction in carvedilol drug dosage (p=0.0001). Moreover, AT/TT genotype carriers on β-blockers showed improved ejection fraction from 27% to 36% (p=0.0007) and increased hospitalization-free survival in comparison to other HF patients. HF patients with AA genotype showed an increased rate of hospital admission in comparison with patients with the AT/TT genotype. HF subgroups with the AT/TT genotype showed an increased hospitalization-free survival versus subgroups with the AA genotype.

CONCLUSIONS

GRK5 Gln41>Leu polymorphism in response to β-blocker therapy improved cardiac function in HF patients.

RELEVANCE FOR PATIENTS

This study presents a comprehensive clinicofunctional pharmacogenetic characterization of GRK5 Gln41>Leu polymorphism in a cohort of Indian HF patients. GRK5 Gln41>Leu polymorphism can confer improved cardiac function and reduce hospitalization, thus improving the quality of life in HF patients.

Left Atrial Function in Different Modes of Heart-Rate Lowering Therapy with Beta-Blockers in Patients with Recurrent Atrial Fibrillation and Hypertension

Aim. To study the impact of heart rate (HR) reduction with beta-blockers (BB) on left atrial (LA) function in hypertensive patients with paroxysmal or persistent mild symptomatic atrial fibrillation.

Material and methods. In this open prospective trial we randomly assigned patients with hypertension, sinus rhythm, elevated heart rate (≥70 bpm), and recurrent atrial fibrillation (EHRA 2A or less) to receive BB with a target HR of less or greater than 70 bpm for at least 4 months. All the patients underwent an echocardiogram [left atrial (LA) function was assessed as emptying fraction]and applanation tonometry at baseline and after 4 months. Primary endpoint was median LA emptying fraction (LAEF) measurement at the end of the study.

Results. 47 patients were randomized to group with a target HR of ≤70 bpm and 44 patients to >70 bmp. Among them 44 and 41 patients completed the study. Median follow up was 4.4 months. At the end of the study (4.5 months) median HR was 62 [60; 67] bmp in ≤70 group and 73 [72; 76] bpm in >70 group. Both groups received similar antihypertensive therapy and there were no intergroup differences in systolic and diastolic blood pressure. At the end of the study, patients in ≤70 group had significantly lower LAEF compared with >70 group (37% vs 42%; p=0.01). E’avg was lower and augmentation index was higher in ≤70 group as compared to >70. In regression analysis, after E’avg and augmentation index were included in the model, the association between LAEF and randomization group lost its significance.

Conclusion. Beta blockers treatment with strict HR reduction (≤70 bpm) significantly reduced LA function as compared to lenient target HR (>70 bpm).

Comprehensive assessment of left atrial and ventricular remodeling in paroxysmal atrial fibrillation by the cardiovascular magnetic resonance myocardial extracellular volume fraction and feature tracking strain

Atrial fibrillation (AF) is a progressive disease that starts with structural or functional changes in the left atrium and left ventricle, and evolves from paroxysmal toward sustained forms. Early detection of structural or functional changes in the left atrium and left ventricle in the paroxysmal stage could be useful for identifying a higher risk of progression to persistent AF and future cardio-cerebrovascular events. The aim of this study was to test the hypothesis that the feature tracking (FT) left atrial (LA) strain and left ventricular (LV) extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) could detect early changes in remodeling of the left atrium and ventricle in the paroxysmal AF (PAF) stage. The participants were comprised of 106 PAF patients (age, 66.1 ± 10.7 years; 66% male) who underwent clinical CMR before pulmonary vein isolation and 20 control subjects (age, 68.3 ± 8.6 years; 55% male). The CMR-FT LA strain/phasic function and LV-ECV were compared between the PAF and control groups. The total and passive LA empty fraction (LAEF) and LA strain (corresponding to LA reservoir and conduit function) were decreased in the PAF group as compared to the control group. However, active LAEF (corresponding to the LA booster pump function) did not differ significantly between the PAF group (33.9 ± 10.9%) and control group (37.9 ± 13.3%, p = 0.15), while the active LA strain (corresponding to the LA booster pump function) was significantly decreased in the PAF group (11.4 ± 4.3 vs. 15.2 ± 5.6%, p = 0.002). The LV-ECV was significantly greater in the PAF group (28.7 ± 2.8%) than control group (26.6 ± 2.0%, p = 0.002). In the PAF group, the LV-ECV correlated significantly with the E/e′ and LA volume index. Regarding the LA strain, correlations were seen between the LV-ECV and both the reservoir function and conduit function. CMR-FT LA strain in combination with the LV-ECV in a single clinical study offers a potential imaging marker that identifies LA/LV remodeling including subtle LA booster pump dysfunction undetectable by the conventional booster pump LAEF in the PAF stage.

Effect of Obstructive Sleep Apnea and Positive Airway Pressure Therapy on Cardiac Remodeling as Assessed by Cardiac Biomarker and Magnetic Resonance Imaging in Nonobese and Obese Adults

It is unknown whether obesity modifies the effect of obstructive sleep apnea (OSA) and positive airway pressure (PAP) therapy on cardiac remodeling and NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels. We compared NT-proBNP and cardiac magnetic resonance imaging in adults without OSA (n=56) and nonobese (n=73; body mass index <30 kg/m²) and obese (n=136; body mass index ≥30 kg/m²) adults with OSA. We also investigated these traits in nonobese (n=45) and obese (n=78) participants with OSA adherent to 4 months of PAP treatment. At baseline, left ventricular mass to end-diastolic volume ratio, a measure of left ventricular concentricity, was greater in both nonobese and obese participants with OSA compared with those without OSA. Participants with OSA and obesity exhibited reduced phasic right atrial function. No significant differences in baseline NT-proBNP were observed across groups. The effect of PAP treatment on NT-proBNP and left atrial volume index was significantly modified by obesity. In nonobese participants, PAP therapy was associated with a decrease in NT-proBNP (P<0.0001) without a change in left atrial volume index, whereas in obese participants, PAP was associated with an increase in left atrial volume index (P=0.006) without a change in NT-proBNP. OSA was associated with left ventricular concentric remodeling independent of obesity and right atrial dysfunction in participants who were obese. PAP treatment was associated with reduced NT-proBNP in nonobese participants with OSA, but left atrial enlargement in obese participants with OSA, suggesting that PAP-induced reduction in BNP release (which is known to occur during obstructive apnea episodes) may lead to volume retention in obese participants with OSA. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01578031.

Impact of Arterial Hypertension on Left Atrial Size and Function

An increase in left atrial (LA) size in patients with arterial hypertension (AHT) has long been known to be associated with worse cardiovascular morbidity and mortality contributes to various complications, including atrial arrhythmias, stroke, and heart failure. The aim of our study was to evaluate the impact of arterial hypertension (AHT) on the LA size and function. This cross-sectional investigation included one hundred patients with essential hypertension without valvular or structural heart disease and atrial fibrillation. All recruits had a transthoracic echocardiography. LA volumes were measured by area-length method in transthoracic echocardiography at different cardiac cycle times. The indices of LA function were calculated: the reservoir function (total emptying fraction, total emptying volume, and expansion index), the conduit function (passive emptying fraction and passive emptying volume), and the pump function (active emptying fraction and active emptying volume). For all statistical tests, a p value ≤0.05 (represents the degree of significance) is considered statistically significant. In univariate analysis, LA was dilated in 9% of patients. The LA reservoir function and the pump function were increased, respectively, in 85% and 82% of patients. LA conduit function was impaired in 80% of patients. In bivariate analysis, the most powerful factors for this repercussion were diabetes (LA volume MAX dilated in nondiabetic patients (p = 0.037)), obesity (the reservoir function was impaired in obese patients (p = 0.015)), and antihypertensive drugs (the reservoir function was impaired in patients who take beta blockers (p = 0.023); the LA pump function was significantly impaired in patients treated with calcium antagonists (p = 0.012)). This study proved the impact of AHT on the LA size and function. Further investigations are necessary to evaluate the potential predictive value of LA remodeling in hypertensive patients like speckle tracking imaging.

Left Atrial Phasic Function in Patients with Hypertension and Recurrent Atrial Fibrillation: Gender Differences of the Relationship with Diastolic Dysfunction and Central Aortic Pressure

Aim. To evaluate gender-related differences of left atrial (LA) phasic function and structural remodeling in conjunction with the parameters of left ventricular (LV) diastolic dysfunction and central aortic pressure in patients with hypertension and recurrent atrial fibrillation (AF).

Material and methods. The comparative study included 30 men and 37 women with non-valvular AF, hypertension and LV hypertrophy. Conventional echocardiographic measures were extended with LA measures, including its volume in three phases, LAemptying fraction (LAEF), passive and active ejection fraction. The parameters of central aortic pressure were estimated by applanation tonometry method.

Results. No difference was observed between LA and LV structural parameters in men and women. However, in women LAEF (39 [28;50] vs 50 [42;55]%; p=0.02) and E/E’(9.7 [7.8;12] vs 7.1 [5.6;8.6]; p=0.001) were worse than in men. Active LA ejection fraction was higher in women (31 [21;42] vs 24 [19;31]%; p=0.04), whereas passive one – in men (12 [10;14] vs 33 [23;38]%; p<0.001), respectively. Men and women had comparable heart rate (HR), central and peripheral systolic and diastolic pressure, pulse wave velocity (PWV), but women had higher augmentation index (AI) values [33 [28;39] vs 23 [21;28]%; p<0.001], even adjusted by HR (AI 75) (34 [27;39] vs 26 [20;29]%; p<0.001). Only in men PWV weakly correlated with AI 75 (r=0.44; p=0.02 versus r=-0.11; p=0.51, respectively for men and women; intergroup differences: z=2.26; p=0.012). In a multivariate regression analysis in men LAEF was significantly associated with height, weight, E’, E/E’ and glomerular filtration rate (GFR), whereas in women – with E’ and AI 75.

Conclusion. Patients of different genders with recurrent AF and hypertension have comparable LA structuralremodeling. However, women characterized by a more pronounced decrease in LAEF and impaired LV diastolic function than men. In women as distinct from men LV filling is predominantly due to LA systole. In a multivariate regression analysis in men LAEF was significantly associated with height, weight, E’, E/E’ and GFR, whereas in women – with E’ and AI 75. 

Left Atrial Phasic Function by Cardiac Magnetic Resonance Feature Tracking Is a Strong Predictor of Incident Cardiovascular Events

BACKGROUND

The prognostic importance of left atrial (LA) dysfunction is increasingly recognized. Magnetic resonance imaging can provide excellent visualization of the LA wall. We aimed to study the association of LA dysfunction measured using feature-tracking magnetic resonance imaging with incident adverse cardiovascular events among subjects with or without heart failure (HF) at baseline.

METHODS AND RESULTS

We prospectively studied 640 adults without HF (n=419), HF with preserved ejection fraction (n=101), or HF with reduced ejection fraction (n=120). We measured phasic LA function by volumetric and feature-tracking methods to derive longitudinal strain. The composite outcome of incident HF hospitalization or death was adjudicated during a median follow-up of 37.1 months. Measures of LA phasic function were more prominently impaired in subjects with HF with reduced ejection fraction than among subjects with HF with preserved ejection fraction. In unadjusted Cox proportional hazards models, all measures of phasic LA function and volumes (maximum, minimum, and diastatic) were associated with the composite outcome. However, in analyses that adjusted for clinical risk factors, HF status, maximum LA volume, left ventricular mass, and left ventricular ejection fraction, measures of conduit and reservoir LA function, but not booster-pump function, were associated with the composite outcome. The strongest associations were observed for conduit longitudinal strain (standardized hazard ratio, 0.66; 95% CI, 0.49-0.88; P=0.004), conduit strain rate (standardized hazard ratio, 1.59; 95% CI, 1.16-2.16; P=0.0035), and reservoir strain (standardized hazard ratio, 0.68; 95% CI, 0.52-0.89; P=0.0055).

CONCLUSIONS

Phasic LA function measured using magnetic resonance imaging feature tracking is independently predictive of the risk of incident HF admission or death, even after adjusting for LA volume and left ventricular remodeling.

Assessment of the Right and Left Atrial Functions at Midterm After Surgical and Device Atrial Septal Defect Closure: A 2-Dimensional Speckle-Tracking Echocardiographic Study

OBJECTIVES

The available literature lacks data on the comparison of the functions of the right atrium (RA) and left atrium (LA) between surgical atrial septal defect (ASD) closure and percutaneous device ASD closure at follow-up durations of longer than 1 year. We sought to evaluate the RA and LA functions in patients who underwent surgical or device ASD closure between 1 and 5 years postprocedurally.

METHODS

The study population included 30 patients who underwent device ASD closure and 30 who underwent surgical ASD closure, who were matched for the procedural time, age, and sex, in addition to 30 control participants. The RA and LA functions were evaluated with 2-dimensional speckle-tracking echocardiography.

RESULTS

The LA systolic and early diastolic strain and strain rate values and the RA early diastolic strain rate in the device closure group were more likely to be abnormal than in the control group. The RA systolic and late diastolic strain and strain rate values, the RA early diastolic strain rate, and the LA early diastolic strain in the surgical closure group were more likely to be abnormal than in the control group. The RA systolic strain and strain rate in the surgical closure group were more likely to be abnormal than in the device closure group.

CONCLUSIONS

The LA reservoir and conduit functions and the RA contraction function in the patients who underwent device ASD closure and all of the RA functions and the LA conduit function in the patients who underwent surgical ASD closure were more likely to be abnormal than those in the control participants. The RA reservoir function in the surgical closure group was more likely to be abnormal than that in the device closure group.

Dissecting Clinical and Metabolomics Associations of Left Atrial Phasic Function by Cardiac Magnetic Resonance Feature Tracking

Among community cohorts, associations between clinical and metabolite factors and complex left atrial (LA) phasic function assessed by cardiac magnetic resonance (CMR) feature tracking (FT) are unknown. Longitudinal LA strain comprising reservoir strain (εs), conduit strain (εe) and booster strain (εa) and their corresponding peak strain rates (SRs, SRe, SRa) were measured using CMR FT. Targeted mass spectrometry measured 83 circulating metabolites in serum. Sparse Principal Component Analysis was used for data reduction. Among community adults (n = 128, 41% female) (mean age: 70.5 ± 11.6 years), age was significantly associated with εs (β = -0.30, p < 0.0001), εe (β = -0.3, p < 0.0001), SRs (β = -0.02, p < 0.0001), SRe (β = 0.04, p < 0.0001) and SRe/SRa (β = -0.01, p = 0.012). In contrast, heart rate was significantly associated with εa (β = 0.1, p = 0.001) and SRa (β = -0.02, p < 0.0001). Serine was significantly associated with εs (β = 10.1, p = 0.015), SRs (β = 0.5, p = 0.033) and SRa (β = -0.9, p = 0.016). Citrulline was associated with εs (β = -4.0, p = 0.016), εa (β = -3.4, p = 0.002) and SRa (β = 0.4, p = 0.019). Valine was associated with ratio of SRe:SRa (β = -0.4, p = 0.039). Medium and long chain dicarboxyl carnitines were associated with εs (β = -0.6, p = 0.038). Phases of LA function were differentially associated with clinical and metabolite factors. Metabolite signals may be used to advance mechanistic understanding of LA disease in future studies.

Late Systolic Myocardial Loading Is Associated With Left Atrial Dysfunction in Hypertension

BACKGROUND

Late systolic load has been shown to cause diastolic dysfunction in animal models. Although the systolic loading sequence of the ventricular myocardium likely affects its coupling with the left atrium (LA), this issue has not been investigated in humans. We aimed to assess the relationship between the myocardial loading sequence and LA function in human hypertension.

METHODS AND RESULTS

We studied 260 subjects with hypertension and 19 normotensive age- and sex-matched controls. Time-resolved central pressure and left ventricular geometry were measured with carotid tonometry and cardiac magnetic resonance imaging, respectively, for computation of time-resolved ejection-phase myocardial wall stress (MWS). The ratio of late/early ejection-phase MWS time integrals was computed as an index of late systolic myocardial load. Atrial mechanics were measured with cine-steady-state free-precession magnetic resonance imaging using feature-tracking algorithms. Compared with normotensive controls, hypertensive participants demonstrated increased late/early ejection-phase MWS and reduced LA function. Greater levels of late/early ejection-phase MWS were associated with reduced LA conduit, reservoir, and booster pump LA function. In models that included early and late ejection-phase MWS as independent correlates of LA function, late systolic MWS was associated with lower, whereas early systolic MWS was associated with greater LA function, indicating an effect of the relative loading sequence (late versus early MWS) on LA function. These relationships persisted after adjustment for multiple potential confounders.

CONCLUSIONS

A myocardial loading sequence characterized by prominent late systolic MWS was independently associated with atrial dysfunction. In the context of available experimental data, our findings support the deleterious effects of late systolic loading on ventricular-atrial coupling.