Arterial stiffness is associated with left atrial size in hypertensive patients

Optimum Parameters in Ultrasound Coherent Plane Wave Compounding for High LPWV Estimation: Validation on Phantom and Feasibility in 10 Subjects

OBJECTIVES

The aim of this study is to determine the optimum and fine values of the number and transmission angles of tilted plane waves for coherent plane-wave compounding (CPWC)-based high local pulse wave velocity (LPWV) estimation.

METHODS

A Verasonics system incorporating a linear array probe L14-5/38 with 128 elements and a pulsatile pump, CompuFlow1000, were used to acquire radio frequency data of 3, 5, 7, and 9 tilted plane wave sequences with angle intervals from 0° to 12° with a coarse interval increment step of 1°, and the angle intervals from 0° to 2° with a fine interval increment step of 0.25° from a carotid vessel phantom with the LPWV of 13.42 ± 0.90 m/s. The mean value, standard deviation, and coefficients of variation (CV) of the estimated LPWVs were calculated to quantitatively assess the performance of different configurations for CPWC-based LPWV estimation. Ten healthy human subjects of two age groups were recruited to assess the in vivo feasibility of the optimum parameter values.

RESULTS

The CPWC technique with three plane waves (PRF of 12 kHz corresponding to a frame rate of 4000 Hz) with an interval of 0.75° had LPWVs of 13.52 ± 0.08 m/s with the lowest CV of 1.84% on the phantom, and 5.49 ± 1.46 m/s with the lowest CV of 12.35% on 10 subjects.

CONCLUSIONS

The optimum parameters determined in this study show the best repeatability of the LPWV measurements with a vessel phantom and 10 healthy subjects, which support further studies on larger datasets for potential applications.

Atrial Fibrillation and Early Vascular Aging: Clinical Implications, Methodology Issues and Open Questions-A Review from the VascAgeNet COST Action

Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with adverse CV outcomes. Vascular aging (VA), which is defined as the progressive deterioration of arterial function and structure over a lifetime, is an independent predictor of both AF development and CV events. A timing identification and treatment of early VA has therefore the potential to reduce the risk of AF incidence and related CV events. A network of scientists and clinicians from the COST Action VascAgeNet identified five clinically and methodologically relevant questions regarding the relationship between AF and VA and conducted a narrative review of the literature to find potential answers. These are: (1) Are VA biomarkers associated with AF? (2) Does early VA predict AF occurrence better than chronological aging? (3) Is early VA a risk enhancer for the occurrence of CV events in AF patients? (4) Are devices measuring VA suitable to perform subclinical AF detection? (5) Does atrial-fibrillation-related rhythm irregularity have a negative impact on the measurement of vascular age? Results showed that VA is a powerful and independent predictor of AF incidence, however, its role as risk modifier for the occurrence of CV events in patients with AF is debatable. Limited and inconclusive data exist regarding the reliability of VA measurement in the presence of rhythm irregularities associated with AF. To date, no device is equipped with tools capable of detecting AF during VA measurements. This represents a missed opportunity to effectively perform CV prevention in people at high risk. Further advances are needed to fill knowledge gaps in this field.

Cross-Sectional Relationship Between Atrial Conduction Delay and Arterial Stiffness in Patients with Obstructive Sleep Apnea

Aim

Prolonged P-wave duration (PWD), which indicates atrial conduction delay, is a potent precursor of atrial fibrillation (AF) that may be induced by obstructive sleep apnea (OSA). The cardio-ankle vascular index (CAVI), which is an arterial stiffness parameter, is elevated in patients with OSA; moreover, an increased CAVI is associated with atrial conduction delay through left atrium enlargement in association with left ventricular diastolic dysfunction. We aimed to examine the relationship between the CAVI and PWD in patients with OSA.

Methods

We included patients with a sinus rhythm who underwent overnight polysomnography. We measured the PWD and CAVI on standard 12-lead electrocardiograms; further, we analyzed the relationship between PWD and CAVI.

Results

We analyzed data from 300 participants (men, 89.0%; mean age, 52.3 ± 13.1 years; and body mass index, 26.2 ± 3.9 kg/m2). The mean PWD was 104.4 ± 10.4 ms while the mean CAVI was 7.5 ± 1.5. PWD was significantly correlated with CAVI (r = 0.478, p < 0.001); additionally, PWD and CAVI were directly associated with OSA severity (p = 0.002 and p = 0.002, respectively). Multivariate regression analysis revealed an independent significant correlation of PWD and CAVI with OSA severity.

Conclusion

In patients with OSA, an increase in arterial stiffness is associated with atrial conduction delay.

Arterial stiffness and atrial fibrillation: shared mechanisms, clinical implications and therapeutic options

Arterial stiffness (AS) and atrial fibrillation (AF) share commonalities in molecular and pathophysiological mechanisms and numerous studies have analyzed their reciprocal influence. The gold standard for AS diagnosis is represented by aortic pulse wave velocity, whose measurement can be affected by arrhythmias characterized by irregularities in heart rhythm, such as AF. Growing evidence show that patients with AS are at high risk of AF development. Moreover, the subset of AF patients with AS seems to be more symptomatic and rhythm control strategies are less effective in this population. Reducing AS through de-stiffening interventions may be beneficial for patients with AF and can be a new appealing target for the holistic approach of AF management. In this review, we discuss the association between AS and AF, with particular interest in shared mechanisms, clinical implications and therapeutic options.

Association between arterial stiffness and walking capacity in older adults

BACKGROUND AND AIM

Arterial stiffening - a process that is largely due to intimal thickening, collagen disposition or elastin fragmentation - significantly contributes to cardiovascular events and mortality. There is also some evidence that it may negatively affect physical function. This study aimed to evaluate whether arterial stiffness was associated with measures of walking capacity in a large, population-based sample of highly aged older adults.

METHODS

A population-based sample of 910 community-dwelling adults (aged 75, 80, or 85 years) were investigated in a cross-sectional observational study. Pulse wave velocity (PWV), a surrogate marker of arterial stiffness, was estimated based on the oscillometric recording of pulse waves at the brachial artery site. Walking capacity was assessed by 10-meter habitual walking speed, 10-meter maximum walking speed, and six-minute walk distance. We used multiple linear regression models to examine possible associations between PWV and parameters of walking capacity, and we adjusted the models for sex, age, socioeconomic status, anthropometry, physician-diagnosed diseases, prescription medication, smoking history, physical activity, and mean arterial pressure. Continuous variables were modelled using restricted cubic splines to account for potential nonlinear associations.

RESULTS

Mean (standard deviation) 10-meter habitual walking speed, 10-meter maximum walking speed, and six-minute walk distance were 1.3 (0.2) m/s, 1.7 (0.4) m/s, and 413 (85) m, respectively. The fully adjusted regression models revealed no evidence for associations between PWV and parameters of walking capacity (all p-values >0.05).

CONCLUSION

Our results did not confirm previous findings suggesting a potential negative association between arterial stiffness and walking capacity in old age. Longitudinal studies, potentially taking additional confounders into account, are needed to disentangle the complex relationship between the two factors.

Clinical Applications Measuring Arterial Stiffness: An Expert Consensus for the Application of Cardio-Ankle Vascular Index

BACKGROUND

The purpose of this document is to provide clinicians with guidance, using expert consensus, to help summarize evidence and offer practical recommendations.

METHODS

Expert Consensus Documents are intended to provide guidance for clinicians in areas in which there are no clinical practice guidelines, especially for new and evolving tests such as arterial stiffness measurements, until any formal guidelines are released.

RESULTS

This expert consensus document is intended as a source of information for decision-making and to guide clinician-patient discussions in various clinical scenarios.

CONCLUSIONS

The goal is to help clinicians and patients make a more informed decision together.

Arterial stiffness and atrial fibrillation: A review

Arterial stiffness has been investigated as part of the physiopathology of arterial hypertension since the 1970s. Its role in increasing the "pulsatile load" imposed over the Left Ventricle (LV) has been intensely studied recently and has helped in understanding the mechanisms of Atrial Fibrillation (AF) in hypertensive patients. This paper aims to review the main evidence on this issue and establish possible mechanisms involved in the development of AF in patients with arterial stiffness. A PubMed search was performed, and selected articles were searched for references focusing on this topic. In the long term, lower blood pressure levels allow for arterial wall remodeling, leading to a lower stiffness index. To this day, however, there are no available treatments that directly promote the lowering of arterial wall stiffness. Most classes of anti-hypertensive drugs ‒ with stronger evidence for beta-blockers and diuretics ‒ could be effective in reducing arterial stiffness. There is strong evidence demonstrating an association between arterial stiffness and AF. New studies focusing on arterial stiffness and pre-fibrillatory stages would strengthen this causality relation.

Recurrence of atrial fibrillation after pulmonary vein isolation in dependence of arterial stiffness

Background

Arterial stiffness (AS) has emerged as a strong predictor of cardiovascular (CV) diseases. Although increased AS has been described as a predictor of atrial fibrillation (AF), its role as a risk marker for AF recurrence has not yet been elucidated.

Methods

Patients with AF who underwent pulmonary vein isolation (PVI) were included in this study. Presence of AS was evaluated by measuring aortic distensibility (AD) of the descending aorta by transoesophageal echocardiography.

Results

In total, 151 patients (mean ± standard deviation (SD) age 71.9 ± 9.8 years) were enrolled and followed for a median duration of 21 months (interquartile range 15.0–31.0). During follow-up, AF recurred in 94 (62.3%) patients. AF recurrence was seen more frequently in patients with permanent AF (27% vs 46%, p = 0.03) and in those who had undergone prior PVI (9% vs 23%, p = 0.02). AD was significantly reduced in patients with AF recurrence (mean ± SD 2.6 ± 2.3 vs 1.5 ± 0.7 × 10⁻³ mm Hg⁻¹, p < 0.0001), as well as left atrial volume index (LAVI) (mean ± SD 29 ± 12 vs 44 ± 15 ml/m², p < 0.0001). Multivariable analysis revealed LAVI (odds ratio (OR) 2.9, 95% confidence interval (CI) 1.2–3.4) and AS (OR 3.6, 95% CI 2.8–4.1) as independent risk factors of AF recurrence.

Conclusion

Increased AS and left atrial size were independent predictors of AF recurrence after PVI. AD as surrogate marker of AS seemed to reflect the overall CV risk. In addition, AD was significantly correlated with left atrial size, which suggests that increased AS leads to atrial remodelling and thus to AF recurrence.

Trial registration

German registry for clinical studies (DRKS), DRKS00019007.

Supplementary Information

The online version of this article (10.1007/s12471-021-01644-w) contains supplementary material, which is available to authorized users.

The Relationship Between Cardio-Ankle Vascular Index and Left Atrial Phasic Function in Hypertensive Patients With Preserved Ejection Fraction

Background: To investigate the relationship between arterial stiffness, reflected by cardio-ankle vascular index (CAVI) value, and left atrial (LA) phasic function in hypertensive patients with preserved left ventricular ejection fraction (LVEF).

Methods: We retrospectively studied 165 consecutive patients (mean age, 66.5 ± 11.7 years) diagnosed with hypertension with preserved LVEF who had undergone CAVI measurement and echocardiography on the same day. The latter included speckle-tracking echocardiography to assess LA phasic function (reservoir, conduit, and pump strain) and left ventricular global longitudinal strain (LVGLS).

Results: The results of univariate analysis showed CAVI value to be correlated with LA reservoir strain and LA conduit strain (r = −0.387 and −0.448, respectively; both P < 0.0001). The results of multiple linear regression analysis showed CAVI value to be independently related to age (β = 0.241, P = 0.002) and LA conduit strain (β = −0.386, P = 0.021) but not LV mass index, LA volume index, or LV systolic function (including LVGLS).

Conclusion: In hypertensive patients with preserved LVEF, increased CAVI value appears to be independently associated with impaired LA phasic function (particularly LA conduit function) before LA and LV remodeling. CAVI determination to assess arterial stiffness may be useful in the early detection of interactions between cardiovascular abnormalities in hypertensive patients.

Atrial fibrillation is associated with increased central blood pressure and arterial stiffness

Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and beta blockers (BBs) are the drugs of choice for rate or rhythm control in these patients. The purpose of this study was to describe differences in arterial stiffness (AS), central blood pressure (cBP), and the role of BBs on cBP in patients with AF compared to healthy individuals. The authors included 76 patients with paroxysmal/persistent AF. Carotid‐femoral pulse wave velocity (PWV) and cBP were measured and compared with data from 75 healthy individuals. Patients with AF had higher PWV (8.0 m/s vs. 7.2 m/s, p < .001), central systolic blood pressure (cSBP) (118 mm Hg vs. 114 mm Hg, p = .033), central pulse pressure (cPP) (39 mm Hg vs. 37 mm Hg, p = .035) and lower pulse pressure amplification (PPA) (1.24 vs. 1.30, p = .015), without differences in peripheral blood pressure (pBP) and heart rate (HR). AF patients had significantly increased PWV (β= 0.500, p = .010, adjusted R² = 0.37) after adjustment for confounding factors. The use of BBs significantly reduced PPA (β = ‐0.059, p = .017, adjusted R² = 0.30). AF patients have higher PWV, cSBP, cPP, and lower PPA, compared to healthy patients. These findings support the role of AS in the development of AF. Use of BBs is related to a potential adverse effect on cBP.

Endothelial dysfunction and vascular maladaptation in atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia and is associated with worsened morbidity and mortality. The prevalence of AF is estimated to increase with an ageing population resulting in an ever-increasing burden on the healthcare system. Despite improvements in AF treatment, several questions remain unanswered in relation to the development and progression of AF. In this review, we discuss the evidence supporting the presence of vascular dysfunction in the development of AF, but also as a final common pathway explaining why AF constitutes a markedly increased risk of cardiovascular morbidity and mortality. Specifically, we summarise the work performed in humans related to the impact of AF on vascular structure and function, and whether measures of vascular function predict AF progression and the development of cardiovascular events. Subsequently, we discuss the potential mechanisms linking AF to the development of vascular dysfunction. Finally, we propose future perspectives of vascular health and AF, advocating a strong focus on regular exercise training as a safe and effective strategy to improve vascular function and, hence, reduce the risk for development and progression of AF and its associated risk for cardiovascular events.

Determinants of arterial stiffness in patients with atrial fibrillation

BACKGROUND

Arterial stiffness has emerged as a strong predictor of cardiovascular disease, end-organ damage and all-cause mortality. Although increased arterial stiffness has been described as a predictor of atrial fibrillation, the relationship between arterial stiffness and atrial fibrillation is uncertain.

AIM

We assessed arterial stiffness in patients with atrial fibrillation compared with that in a control group.

METHODS

We enrolled 151 patients with atrial fibrillation who underwent pulmonary vein isolation (mean age 71.1±9.8 years) and 54 control patients with similar cardiovascular risk profiles and sinus rhythm, matched for age (mean age 68.6±15.7 years) and sex. Aortic distensibility as a measure of arterial stiffness was assessed by transoesophageal echocardiography. Patients with atrial fibrillation were followed over a median of 21 (15 to 31) months.

RESULTS

Compared with control patients, patients with atrial fibrillation had significantly lower aortic distensibility (1.8±1.1 vs. 2.1±1.1 10^-3mmHg^-1; P=0.02). Age (hazard ratio 0.67, 95% confidence interval 0.003 to 0.03; P=0.02) and pulse pressure (hazard ratio -1.35, 95% confidence interval -0.07 to -0.03; P<0.0001) were the strongest predictors of decreased aortic distensibility in the study cohort. This effect was independent of the type of atrial fibrillation (paroxysmal/persistent). During follow-up, decreased aortic distensibility was a predictor of cardiovascular and all-cause hospitalizations, as well as recurrences of atrial fibrillation, with a higher incidence rate of events in patients in the lowest aortic distensibility quartile (P=0.001).

CONCLUSIONS

Aortic distensibility was significantly reduced in patients with atrial fibrillation, with age and pulse pressure showing the strongest correlation, independent of the type of atrial fibrillation. Additionally, decreased aortic distensibility was associated with cardiovascular and all-cause hospitalizations, as well as recurrences of atrial fibrillation, which showed a quartile-dependent occurrence.

Arterial Stiffness in Aging: Does It Have a Place in Clinical Practice?: Recent Advances in Hypertension

Aortic stiffness increases markedly with age and is associated with excess risk for various adverse clinical outcomes, including heart disease, dementia, and kidney disease. Although evidence for adverse effects of aortic stiffening is overwhelming, integration of direct and indirect measures of aortic stiffness into routine clinical assessment has lagged behind the science. This brief review will examine recent evidence supporting the value of stiffness as an important new risk factor for hypertension and cardiovascular disease and will offer suggestions for incorporating stiffness measures into routine clinical practice.

Nocturia and electrocardiographic abnormalities among patients at an inner-city cardiology clinic

AIMS

Nocturia has been increasingly recognized as a potential manifestation of cardiovascular disease. However, the relationship between nocturia and electrocardiographic (ECG) abnormalities has not been studied. This study aims to characterize the diagnostic utility of nocturia in identifying left ventricular hypertrophy (LVH), left atrial enlargement (LAE), and prolonged QTc on ECG.

METHODS

Retrospective analysis of nocturnal voiding frequency and contemporaneous ECG data from consecutive patients evaluated at a university-based outpatient cardiology clinic. Three sets of three incremental binary multiple logistic regression models controlling for (1) age, (2) sex and race, and (3) body mass index, hypertension, diabetes mellitus, and diuretic utilization were performed to determine whether nocturia was predictive of LVH, LAE, and prolonged QTc.

RESULTS

Included patients (n = 143, 77.6% nocturia) were predominantly African-American (89.5%), female (74.1%), and obese (61.5%), of whom 44.1%, 41.3%, and 27.3% had LVH, LAE, and prolonged QTc, respectively. Older age, African-American race, obesity, hypertension, diuretic use, LVH, and LAE were significantly associated with nocturia on univariate analysis. No significant differences were observed in the strength of associations between nocturia and LVH, LAE, or QTc prolongation based on age. Nocturia independently predicted LVH in Models I-III (odds ratios [ORs], 2.99-3.20; relative risks [RRs], 1.18 for all, p ≤ .046) and LAE in Models I-III (ORs, 4.24-4.72; RRs, 1.21 for all, p ≤ .015). No significant associations were observed between nocturia and prolonged QTc.

CONCLUSIONS

Nocturia may be a risk marker for underlying structural cardiac abnormalities.

Left atrial stiffness index as a marker of early target organ damage in hypertension

This study aimed to evaluate left atrial (LA) mechanics using two-dimensional speckle-tracking echocardiography (2DSTE) and investigate their correlations with measures of target organ damage (TOD) in hypertension. We enrolled 42 healthy controls (Group I) and 286 hypertension patients: Group II (n = 79) had an LA volume index (LAVI) <28 ml/m²; Group III (n = 92) had an LAVI ≥28 ml/m²; and Group IV (n = 115) had hypertension with left ventricular hypertrophy (LVH). We measured the following parameters: LA reservoir strain and strain rate (LA_S-S, LA_SR-S), LA conduit strain and strain rate (LA_S-E and LA_SR-E), and LA booster strain and strain rate (LA_S-A and LA_SR-A). The LA stiffness index (LASI) was defined as the ratio of early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e') to LA_S-S. We performed correlation and regression analyses of individual TOD with LA phasic functions, the LASI, and cardiovascular risk factors. Our findings showed that there was a trend toward a gradual increase in the LASI from controls to normal LA and enlarged LA patients and finally to hypertrophic LV patients. The LASI was significantly higher in Group III [0.28 (0.20, 0.38)] than in Group I [0.20 (0.16, 0.23)] and Group II [0.22 (0.18, 0.27)] and was the highest in Group IV [0.33 (0.26, 0.43)]. The LA reservoir and conduit function gradually decreased from Group I to Group IV. Multivariate regression analysis revealed that the LASI was independently correlated with individual TOD. In conclusion, abnormal LA mechanics precede LA enlargement and LVH, and an increased LASI can be used as a marker of early TOD in hypertension.

Aortic stiffness-Is kynurenic acid a novel marker? Cross-sectional study in patients with persistent atrial fibrillation

Objective

Although a number of modifiable and non-modifiable causes were implicated in arterial stiffness, its pathogenesis remains elusive, and very little is known about aortic elasticity in supraventricular arrhythmias. The potential role of disturbed kynurenine metabolism in the pathogenesis of cardiovascular disease has been recently suggested. Thus, we studied the correlations of aortic stiffness and echocardiographic parameters with biochemical markers and serum level of kynurenic acid (KYNA), an endothelial derivative of tryptophan, formed along the kynurenine pathway, among patients with atrial fibrillation (AF).

Methods

Study cohort comprised 100 patients with persistent AF (43 females/57 males). Arterial stiffness index (ASI), structural and functional indices of left atrium (LA) and left ventricle (LV) were evaluated electrocardiographically. Biochemical analyses included the measurements of serum KYNA (HPLC) and of the selected markers of lipids and glucose metabolism, thyroid status, kidney function, inflammation and coagulation.

Results

KYNA (β = 0.389, P = 0.029), homocysteine (β = 0.256, P = 0.40), total cholesterol (β = 0.814; P = 0.044), LDL (β = 0.663; P = 0.44), TSH (β = 0.262, P = 0.02), fT₃ (β = -0.333, P = 0.009), fT₄ (β = -0.275, P = 0.043) and creatinine (β = 0.374, P = 0.043) were independently correlated with ASI. ASI was also independently associated with LV end-systolic diameter (LVEDd; β = 1.751, P = 0.045), midwall fractional shortening (mFS; β = -1.266, P = 0.007), ratio mFS/end-systolic stress (mFS/ESS; β = -0.235, P = 0.026), LV shortening fraction (FS; β = -0.254, P = 0.017), and LA volume index (LAVI; β = 0.944, P = 0.022).

Conclusions

In patients with AF, aortic stiffness correlated positively with KYNA, biochemical risk factors of atherosclerosis and with the indices of diastolic dysfunction of LV and LA. Revealed relationship between ASI and KYNA is an original observation, suggesting a potential role of disturbed kynurenine metabolism in the pathogenesis of arterial stiffening. KYNA, synthesis of which is influenced by homocysteine, emerges as a novel, non-classical factor associated with ASI in patients with AF.

Assessment of Arterial Stiffness in Patients With Resistant Hypertension: Additional Insights Into the Pathophysiology of This Condition?

BACKGROUND

Good understanding of the pathophysiological mechanism(s) of resistant hypertension (RH) and the relationship to vascular dysfunction is important for optimal blood pressure control.

METHODS AND RESULTS

The aim of this review article is to summarize the available data on the methods of arterial stiffness assessment, and their usefulness in RH. Several studies that provide information on the noninvasive methods of evaluation of arterial stiffness have been discussed; specifically, pulse wave velocity (PWV) and augmentation index (AIx) tests. Increased arterial stiffness, elevated AIx, and impaired endothelial function all act as indicators and predictors of cardiovascular events in patients with hypertension (HTN).

CONCLUSION

Our review suggests that PWV and AIx are impaired in patients with severe HTN. Early assessment of these characteristics can potentially be of value in patients with RH.

Cohort Study of Repeated Measurements of Serum Urate and Risk of Incident Atrial Fibrillation

Background Current evidence on the association between serum urate and risk of atrial fibrillation ( AF ) is limited by cross-sectional designs and 1-time measurement of serum urate. The roles of serum urate, gout-related inflammation, and systemic inflammation in the etiology of AF are currently unknown. This gap is important, given that systemic inflammation is a recognized risk factor for AF . Methods and Results We conducted a prospective cohort study of 123 238 Chinese patients from 2006 to 2014. Serum urate concentrations were measured in 2006, 2008, 2010, and 2012. Incident AF cases were identified via biennial 12-lead ECG assessment. We used a Cox proportional hazards model to examine the sex-specific associations of cumulative average serum urate and changes in serum urate accounting for baseline level with risk of incident AF . We also assessed the joint associations of serum urate and high-sensitivity C-reactive protein levels. Comparing extreme categories, participants with the highest quintile of serum urate had 1.91-fold higher risk of AF (adjusted hazard ratio: 1.91; 95% CI, 1.32-2.76; P=0.001 for trend). Participants with both high serum urate and high-sensitivity C-reactive protein had 2.6-fold elevated risk of incident AF compared with those with normal levels of serum urate and high-sensitivity C-reactive protein (adjusted hazard ratio: 2.63; 95% CI, 1.63-4.23). Conclusions High serum urate levels and increases in serum urate over time were associated with increased risk of incident AF . Patients with high levels of both serum urate and high-sensitivity C-reactive protein had substantially higher risk of AF .

Biomarkers of Atrial Fibrillation in Hypertension

Background:

Atrial fibrillation (AF) is the most frequently encountered cardiac arrhythmia globally and substantially increases the risk for thromboembolic disease. Albeit, 20% of all cases of AF remain undiagnosed. On the other hand, hypertension amplifies the risk for both AF occurrences through hemodynamic and non-hemodynamic mechanisms and cerebrovascular ischemia. Under this prism, prompt diagnosis of undetected AF in hypertensive patients is of pivotal importance.

Method:

We conducted a review of the literature for studies with biomarkers that could be used in AF diagnosis as well as in predicting the transition of paroxysmal AF to sustained AF, especially in hypertensive patients.

Results:

Potential biomarkers for AF can be broadly categorized into electrophysiological, morphological and molecular markers that reflect the underlying mechanisms of adverse atrial remodeling. We focused on P-wave duration and dispersion as electrophysiological markers, and left atrial (LA) and LA appendage size, atrial fibrosis, left ventricular hypertrophy and aortic stiffness as structural biomarkers, respectively. The heterogeneous group of molecular biomarkers of AF encompasses products of the neurohormonal cascade, including NT-pro BNP, BNP, MR-pro ANP, polymorphisms of the ACE and convertases such as corin and furin. In addition, soluble biomarkers of inflammation (i.e. CRP, IL-6) and fibrosis (i.e. TGF-1 and matrix metalloproteinases) were assessed for predicting AF.

Conclusion:

The reviewed individual biomarkers might be a valuable addition to current diagnostic tools but the ideal candidate is expected to combine multiple indices of atrial remodeling in order to effectively detect both AF and adverse characteristics of high risk patients with hypertension.

Association of central blood pressure with left atrial structural and functional abnormalities in hypertensive patients: Implications for atrial fibrillation prevention

Aims

Functional and structural abnormalities of the left atrium have been demonstrated to be clinically and prognostically significant in a range of cardiovascular disorders, increasing the risk of atrial fibrillation. Among the potential contributors to these aberrations, central arterial factors remain insufficiently defined. Accordingly, we sought to investigate the determinants of left atrium abnormalities in hypertension, with special focus on central haemodynamics.

Methods

In this retrospective, cross-sectional study, 263 patients (age 63.8 ± 8.0 years) with uncomplicated hypertension underwent echocardiography including left atrium strain (LAS) and volume analysis, and central haemodynamics assessment using radial tonometry.

Results

Patients were grouped depending on LAS and left atrium volume index (LAVI), using externally validated cutpoints (34.1% for LAS and 34 ml/m2for LAVI). The subset with lower LAS ( n = 124) demonstrated higher central (cPP) and brachial pulse pressure (bPP), ventricular- arterial coupling, left ventricular mass index (LVMI) and LAVI, and lower global left ventricular longitudinal strain and early diastolic tissue velocity (e′). Patients with higher LAVI ( n = 119) presented higher systolic blood pressure, cPP, bPP, central augmentation pressure, LVMI and E/e′ ratio and lower LAS. In multivariable analysis, cPP was independently associated with both LAS ( β = –0.22; p = 0.002) and LAVI ( β = 0.21; p = 0.003). No independent associations with left atrium parameters were shown for bPP.

Conclusion

Higher cPP is detrimentally associated with left atrium structural and functional characteristics, thus providing a possible pathophysiological link with the development of substrate for atrial fibrillation. Prophylaxis of atrial fibrillation might be another argument for consideration in the treatment strategy in hypertension targeted measures addressing central blood pressure.

Impact of Aging on Endurance and Neuromuscular Physical Performance: The Role of Vascular Senescence

The portion of society aged ≥60 years is the fastest growing population in the Western hemisphere. Aging is associated with numerous changes to systemic physiology that affect physical function and performance. We present a narrative review of the literature aimed at discussing the age-related changes in various metrics of physical performance (exercise economy, anaerobic threshold, peak oxygen uptake, muscle strength, and power). It also explores aging exercise physiology as it relates to global physical performance. Finally, this review examines the vascular contributions to aging exercise physiology. Numerous studies have shown that older adults exhibit substantial reductions in physical performance. The process of decline in endurance capacity is particularly insidious over the age of 60 years and varies considerably as a function of sex, task specificity, and individual training status. Starting at the age of 50 years, aging also implicates an impressive deterioration of neuromuscular function, affecting muscle strength and power. Muscle atrophy, together with minor deficits in the structure and function of the nervous system and/or impairments in intrinsic muscle quality, plays an important role in the development of neuromotor senescence. Large artery stiffness increases as a function of age, thus triggering subsequent changes in pulsatile hemodynamics and systemic endothelial dysfunction. For this reason, we propose that vascular senescence has a negative impact on cerebral, cardiac, and neuromuscular structure and function, detrimentally affecting physical performance.

Greater nighttime blood pressure variability is associated with left atrial enlargement in atrial fibrillation patients with preserved ejection fraction

Left atrial enlargement is an independent risk factor for ischemic stroke in patients with atrial fibrillation. Little is known regarding the association between nighttime blood pressure variability and left atrial enlargement in patients with atrial fibrillation and preserved ejection fraction. The study population consisted of 140 consecutive patients with atrial fibrillation (mean age 64 ± 10 years) with preserved ejection fraction (≥50%). Nighttime blood pressure was measured at hourly intervals, using a home blood pressure monitoring device. Nighttime blood pressure variability was expressed as the standard deviation of all readings. Left atrial volume index was measured using the modified Simpson's biplane method with transthoracic echocardiography. Multiple regression analysis indicated that nighttime mean systolic/diastolic blood pressure and its variability remained independently associated with left atrial enlargement after adjustment for age, sex, anti-hypertensive medication class, and left ventricular mass index (P < 0.01). When patients were divided into four groups according to nighttime blood pressure and its variability, the group with higher nighttime blood pressure and its variability had significantly larger left atrial volume than the group with lower nighttime blood pressure and its variability (46.6 ml/m² vs. 35.0 ml/m², P < 0.0001). Higher nighttime blood pressure and its variability are associated with left atrial enlargement. The combination of nighttime blood pressure and its variability has additional predictive value for left atrial enlargement. Intensive intervention for these high-risk patients may avoid or delay progression of left atrial enlargement and reduce the risk of stroke.

The relation between blood pressure components and left atrial volume in the context of left ventricular mass index

Left atrial enlargement (LAE) is a risk factor for cardiovascular complications and death. In hypertensive patients, LAE is usually due to left ventricular (LV) hypertrophy and diastolic dysfunction. We aimed to identify factors associated with LAE in patients with increased and normal left ventricular mass index (LVMI) with reference to pulsatile and steady components of blood pressure (BP).The study was carried out as a cross-sectional observation. In a group of inhabitants of suburban area of Cracow, Poland, we measured office, ambulatory and central BP, carotid-femoral pulse wave velocity (PWV), as well as echocardiographic indices and gathered anthropometric data, information on habits and relevant medical history. Further, with division according to sex-stratified dichotomised LVMI, we performed correlation analysis to identify possibly significant relations between measures of left atrial volume and other studied parameters. We also fitted regression models in order to assess the respective value of steady and pulsatile BP components as factors related to measures of left atrial volume.The mean age of 205 patients (136 females-66%) was 53.6 ± 8.3 years. We found higher values of PWV, office, ambulatory and central BPs in the group of LVMI above median value. This group had also greater left atrial volume index (LAVI), which correlated with LVMI (r = 0.36, P < .001) and ratio of early diastolic mitral peak flow velocity to early diastolic mitral annulus mean velocity in tissue Doppler imaging (E/e') (r = 0.24, P = .04).In the group of LVMI below the median, LAVI correlated with pulsatile and steady BP components. LAVI was independently predicted by mean arterial pressure (MAP) obtained from both ambulatory (MAP24h, β= 0.15; P = .045) and office measurements (MAPoffice, β = 0.35; P = .004), but not by pulse pressure.LV mass and function are the main determinants of LAVI. However, in persons with lower LV mass, LAVI depends on the steady component of blood pressure, but not pulsatile one. Increased LAVI reflects early changes in response to systemic blood pressure elevation.

Carotid Artery Stiffness and Development of Hypertension in People with Paraplegia and No Overt Cardiovascular Disease: A 7-year Follow-up Study

Objectives

The aim of this study was to compare arterial stiffness between people with paraplegia and able-bodied persons (ABPs) and to assess cardiovascular markers that may be predictive of the development of arterial hypertension in people with spinal cord injury (SCI).

Setting

This study was conducted at rehabilitation Hospital, Udine (Italy).

Methods

Fifty-seven patients with SCI were prospectively enrolled and compared with 88 healthy ABPs. All patients underwent comprehensive transthoracic echocardiography, and one-point left common carotid artery (CCA) color-Doppler study for arterial stiffness.

Results

Patients with SCI had significantly lower body mass index (BMI) and diastolic blood pressure (BP) compared with ABPs, and significantly higher carotid stiffness values (and lower arterial compliance) (P < 0.05) after adjustment for age, sex, BMI, physical activity, and heart rate. The SCI patients had lower values of the right ventricular function parameters (tricuspid annular plane systolic excursion and right Sm; P < 0.0001), increased wall thickness, and impaired diastolic function. At 7-year follow-up, 10.5% of SCI patients showed high BP; they were significantly heavier with a tendency toward increased abdominal obesity after adjustment for age and systolic BP. BMI was found to be an independent predictor of the development of hypertension.

Conclusions

Patients with posttraumatic chronic SCI and no overt cardiovascular disease exhibit higher CCA stiffness along with the left and right ventricular involvement, compared with ABPs. People with paraplegia who develop arterial hypertension show increased CCA stiffness mediated by obesity. Lifestyle modifications and weight control should be promoted in all patients with SCI, even at a very early stage.

Abnormal Remodeling of Subcutaneous Small Arteries Is Associated With Early Diastolic Impairment in Metabolic Syndrome

Background

Small artery pathophysiology is frequently invoked as a cause of obesity‐related diastolic heart failure. However, evidence to support this hypothesis is scant, particularly in humans.

Methods and Results

To address this, we studied human small artery structure and function in obesity and looked for correlations between vascular parameters and diastolic function. Seventeen obese patients with metabolic syndrome and 5 control participants underwent echocardiography and subcutaneous gluteal fat biopsy. Small arteries were isolated from the biopsy and pressure myography was used to study endothelial function and wall structure. In comparison with the control group, small arteries from obese participants exhibited significant endothelial dysfunction, assessed as the vasodilatory response to acetylcholine and also pathological growth of the wall. For the obese participants, multiple regression analysis revealed an association between left atrial volume and both the small artery wall thickness (β=0.718, P=0.02) and wall‐to‐lumen ratio (β=0.605, P=0.02). Furthermore, the E:E′ ratio was associated with wall‐to‐lumen ratio (β=0.596, P=0.02) and inversely associated with interleukin‐6 (β=−0.868, P=0.03). By contrast, endothelial function did not correlate with any of the echocardiographic parameters studied.

Conclusions

Although the small arteries studied were not cardiac in origin, our results support a role for small artery remodeling in the development of diastolic dysfunction in humans. Further direct examination of the structure and function of the myocardial resistance vasculature is now warranted, to elucidate the temporal association between metabolic risk factors, small artery injury, and diastolic impairment.

Favorable Pulse Wave Augmentation Indices and Left Ventricular Diastolic Profile in β-Thalassemia Minor

β-Thalassemia minor (β-Τm) is associated with rheological and biochemical alterations that can affect cardiovascular function. We aimed to evaluate the elastic arterial properties and the pulse wave augmentation indices in a population of patients with β-Τm. Seventy-five individuals with β-Τm (age 55.5 [42.75-65.25], women 48%) and 127 controls (age 57 years [48-63], women 55.1%) underwent comprehensive echocardiographic evaluation and applanation tonometry of the radial and femoral artery. Pulse wave analysis revealed that augmentation pressure, augmentation index (AIx), and heart rate-corrected AIx were significantly lower (median [interquartile range]: 8.75 [4.625-13] vs 11 [6.5-14.5], P = .017; 26.5 [17.5-33.375] vs 30.5 [20.75-37.5], P = .014; and 22.25 [15.125-29.5] vs 27 [20.5-33], P = .008, respectively) in the β-Τm group compared to controls. The left atrial active emptying volume was significantly lower and the isovolumic relaxation time was shorter in the β-Τm group compared to the control group (10.2 [7.4-14.4] vs 12.0 [8.6-15.8], P = .040 and 78 [70-90] vs 90 [70-104], P = .034, respectively). β-Thalassemia minor is associated with favorable pulse wave augmentation indices and left ventricular diastolic function profile in asymptomatic individuals with cardiovascular risk factors.

Left Atrial Mechanical Function and Aortic Stiffness in Middle-aged Patients with the First Episode of Atrial Fibrillation

Background:

In the early stages of atrial remodeling, aortic stiffness might be an indication of an atrial myopathy, in particular, atrial fibrosis. This study aimed to investigate the association between left atrial (LA) mechanical function, assessed by two-dimensional speckle tracking echocardiography, and aortic stiffness in middle-aged patients with the first episode of nonvalvular atrial fibrillation (AF).

Methods:

This prospective study included 34 consecutive patients with the first episode of AF, who were admitted to Kartal Koşuyolu Research and Training Hospital between May 2013 and October 2015, and 31 age- and gender-matched healthy controls. During the 1^st month (mostly in the first 2 weeks) following their first admission, 34 patients underwent the first pulse wave measurements. Then, 21 patients were recalled for their second pulse wave measurement at 11.8 ± 6.0 months following their initial admission. Echocardiographic and pulse wave findings were compared between these 34 patients and 31 healthy controls. We also compared the pulse wave and echocardiographic findings between the first and second measurements in 21 patients.

Results:

Pulse wave analysis showed no significant differences between the AF patients and healthy controls with respect to PWV (10.2 ± 2.5 m/s vs. 9.7 ± 2.1 m/s; P = 0.370), augmentation pressure (9.6 ± 7.4 mmHg vs. 9.1 ± 5.7 mmHg; P = 0.740), and aortic pulse pressure (AoPP; 40.4 ± 14.0 mmHg vs. 42.1 ± 7.6 mmHg, P = 0.550). The first LA positive peak of strain was inversely related to the augmentation pressure (r = −0.30; P = 0.02) and aortic systolic pressure (r = −0.26, P = 0.04). Comparison between the two consecutive pulse wave measurements in 21 patients showed similar results, except for AoPP. In 21 patients, the AoPP at the second measurement (45.1 ± 14.1 mmHg) showed a significant increase compared with AoPP at the first measurement (39.0 ± 10.6 mmHg, P = 0.028), which was also higher than that of healthy controls (42.1 ± 7.6 mmHg, P = 0.000).

Conclusion:

The association between aortic stiffness with reduced atrial strain and the key role of AoPP in the development of AF should be considered when treating nonvalvular AF patients with normal LA sizes.

Relations of Arterial Stiffness and Brachial Flow-Mediated Dilation With New-Onset Atrial Fibrillation: The Framingham Heart Study

The relations of measures of arterial stiffness, pulsatile hemodynamic load, and endothelial dysfunction to atrial fibrillation (AF) remain poorly understood. To better understand the pathophysiology of AF, we examined associations between noninvasive measures of vascular function and new-onset AF. The study sample included participants aged ≥45 years from the Framingham Heart Study offspring and third-generation cohorts. Using Cox proportional hazards regression models, we examined relations between incident AF and tonometry measures of arterial stiffness (carotid-femoral pulse wave velocity), wave reflection (augmentation index), pressure pulsatility (central pulse pressure), endothelial function (flow-mediated dilation), resting brachial arterial diameter, and hyperemic flow. AF developed in 407/5797 participants in the tonometry sample and 270/3921 participants in the endothelial function sample during follow-up (median 7.1 years, maximum 10 years). Higher augmentation index (hazard ratio, 1.16; 95% confidence interval, 1.02-1.32; P=0.02), baseline brachial artery diameter (hazard ratio, 1.20; 95% confidence interval, 1.01-1.43; P=0.04), and lower flow-mediated dilation (hazard ratio, 0.79; 95% confidence interval, 0.63-0.99; P=0.04) were associated with increased risk of incident AF. Central pulse pressure, when adjusted for age, sex, and hypertension (hazard ratio, 1.14; 95% confidence interval, 1.02-1.28; P=0.02) was associated with incident AF. Higher pulsatile load assessed by central pulse pressure and greater apparent wave reflection measured by augmentation index were associated with increased risk of incident AF. Vascular endothelial dysfunction may precede development of AF. These measures may be additional risk factors or markers of subclinical cardiovascular disease associated with increased risk of incident AF.

Vascular ageing and interventions: lessons and learnings

This review discusses the relationship between elevated blood pressure, hypertension, arterial stiffness and hence vascular ageing. This is a complex process and the majority of treatments target the consequences of this, rather than the pathophysiology of ageing itself. This is because preventing vascular ageing from occurring is complex and would require very early intervention and lifelong treatment. The process of arteriosclerosis is known to result from reversible and irreversible functional components, and, together, these are responsible for the increased systolic and decreased diastolic blood pressure seen with advancing age. Indeed, hypertension develops as it becomes more difficult for the heart to drive blood flow around the body, as a result of poor ventricular coupling and increased arterial stiffness. Elevated blood pressure is therefore a clinical manifestation of ageing that continues to increase with advancing years, and is also linked with an increased risk of cardiac, cerebrovascular and chronic kidney disease. These manifestations arise due to changing haemodynamics associated with ageing, and therefore treatments that reduce the development of these conditions or delay their progression have the potential to improve patient outcomes. This may be possible with existing therapies as well as new treatments currently under investigation.

Correlation between aortic stiffness and left atrial volume index in hypertensive patients

BACKGROUND

Both arterial stiffness and left atrial volume index are crucial predictors of cardiovascular outcomes in hypertensive patients. The correlation between these two factors has not been previously well established in hypertensive population.

OBJECTIVES

To determine the correlation between arterial stiffness and left atrial volume index in hypertensive patients.

METHODS AND RESULTS

The study was performed in 111 consecutive hypertensive patients (49.5% male, mean age 70.8 ± 10.3 years) undergoing cardiac magnetic resonance imaging (CMR). Arterial stiffness was determined by pulse wave velocity in the thoracic aorta by velocity-encoded imaging. Left atrial volume was assessed by biplane area-length method. Pulse wave velocity was significantly correlated with left atrial volume index in univariate analysis (r = 0.20, p = 0.032). In multivariate analysis, pulse wave velocity, coronary artery disease and left ventricular mass remain independent predictors (β = 1.01, p = 0.02).

CONCLUSION

Increased arterial stiffness correlates with left atrial enlargement in hypertensive patients. The prevention of left atrial enlargement and subsequent complications by specific antihypertensive drugs with positive effect on aortic stiffness warrants further studies.

Aortic pulse wave velocity is associated with measures of subclinical target organ damage in patients with mild hypertension

We evaluated the temporal association between aortic arterial stiffness and subclinical target organ damage, including renal function decline, left ventricular geometric remodeling, and left ventricular diastolic dysfunction in patients with mild hypertension. Automatic pulse wave velocity (PWV) measuring system was applied to examine carotid-femoral PWV (CFPWV) reflecting aortic arterial stiffness in 644 essential hypertensive patients. Clinical data were collected, and cardiac structure and function were assessed by echocardiography. CFPWV was significantly and positively associated with left ventricular mass index (r = 0.153, P = 0.018), relative wall thickness (r = 0.235, P < 0.001), and left atrial diameter (r = 0.192, P = 0.003), and negatively with E/A ratio (r = -0.361, P < 0.001) and creatinine clearance (r = -0.248, P < 0.001). Logistic regression analysis demonstrated that CFPWV remained significantly correlated with renal function decline (P = 0.011), left ventricular diastolic dysfunction (P = 0.009) and left ventricular geometric remodeling (P = 0.020). Higher CFPWV was independently associated with greater burden of subclinical disease in renal impairment, left ventricular geometric remodeling and diastolic dysfunction.

Ambulatory arterial stiffness index is associated with impaired left atrial mechanical functions in hypertensive diabetic patients: A speckle tracking study

Objective:

The ambulatory arterial stiffness index has been proposed as an indicator of arterial stiffness. The aim of this study was to test the hypothesis that increased ambulatory arterial stiffness index might be related with impaired left atrial function in hypertensive diabetic patients with no previous history of cardiovascular disease.

Methods:

Inclusion criteria included office systolic BP> 130 mm Hg or diastolic BP> 80 mm Hg and absence of secondary causes of HT, whereas exclusion criteria LV ejection fraction <50%, history of significant coronary artery disease, chronic renal failure, atrial fibrillation/flutter, second or third-degree atrioventricular block, moderate to severe valvular heart disease, history of cerebrovascular disease, non-dipper hypertensive pattern and sleep apnea. The study was composed of 121 hypertensive diabetic patients. Twenty-four-hour ambulatory blood pressure monitoring and echocardiography were performed in each patient. The relationship between ambulatory arterial stiffness index and left atrial functions was analyzed. AASI was calculated as 1 minus the regression slope of diastolic BP plotted against systolic BP obtained through individual 24-h ABPM.

Results:

The univariate analysis showed that ambulatory arterial stiffness index was positively correlated with age (r=:0.287, p=:0.001), hypertension duration (r=:0.388, p<0.001), fasting plasma glucose (r=:0.224, p=:0.014), HbA1c (r=:0.206, p=:0.023), LDL cholesterol (r=:0.254, p=:0.005), and also overall pulse pressure (r=:0.195, p=:0.002), office-pulse pressure (r=:0.188, p=:0.039), carotid intima-media thickness (r=:0.198, p=:0.029), E/E’ (r=:0.248, p=:0.006), and left atrial volume index (r=:0.237, p=:0.009). Moreover, ambulatory arterial stiffness index was negatively correlated with eGFR (r=:(-) 0.242, p=:0.008), peak left atrial strain during ventricular systole [S-LAs (r=:(-) 0.654, p<0.001)], peak left atrial strain at early diastole [S-LAe (r=:(-)0.215, p=:0.018)], and peak left atrial strain rate during ventricular systole [SR-LAs (r=:(-) 0.607, p<0.001)]. The multiple linear regression analysis showed that ambulatory arterial stiffness index was independently associated with peak left atrial strain rate during ventricular systole (SR-LAs) (p<0.001).

Conclusion:

In hypertensive diabetic patients, increased ambulatory arterial stiffness index is associated with impaired left atrial functions, independent of left ventricular diastolic dysfunction.

Arterial-atrial coupling in untreated hypertension

Recently, there has been growing interest in an interplay of vascular mechanics and heart function (arterial-ventricular-atrial coupling). The contribution of arterial stiffness (AS) to left atrial (LA) enlargement is unclear. The aim of this study was to verify whether the association between carotid AS and LA volume in untreated arterial hypertension is independent of such confounders as age, sex, body mass index (BMI), blood pressure, left ventricular hypertrophy (LVH), left ventricular (LV) diastolic and systolic function. The study included 133 patients, among them 107 individuals with hypertension (51 men and 56 women, mean age 56.8 ± 10.3 years) and 26 matched controls. Each patient was subjected to echocardiography, ultrasonographic measurement of mean carotid intima-media thickness (IMT) and echo-tracking assessment of AS and wave reflection. LA volume was calculated by ellipsoid method. The indexed LA volume showed significant linear correlations with age (r = 0.32; p < 0.05), BMI (r = 0.21; p < 0.05), pulse pressure (r = 0.26; p < 0.05), B-type natriuretic peptide (r = 0.64; p < 0.05), LV end-diastolic volume (r = 0.42; p < 0.05), LV mass index (LVMI; r = 0.58; p < 0.05), septum thickness (r = 0.40; p < 0.05), posterior wall thickness (r = 0.34; p < 0.05), early filling wave of mitral inflow (E; r = 0.30; p < 0.05), early diastolic myocardial velocity of mitral annulus (e'; r = - 0.22; p < 0.05), E/e' ratio (r = 0.45; p < 0.05), IMT (r = 0.26; p < 0.05) and augmentation index (AI; r = 0.27; p < 0.05). Progressive multivariate analysis identified LVMI, age, AI and BMI as independent determinants of indexed LA volume in patients with arterial hypertension. The study showed the significant relationship between wave reflection expressed by AI and LA structural remodeling, which supports the hypothesis of arterial-atrial coupling in hypertension.

Age, left atrial dimension and arterial stiffness after external cardioversion of atrial fibrillation. A vascular component in arrhythmia maintenance? Results from a preliminary study

BACKGROUND AND AIMS

Atrial fibrillation (AF) is the most frequent arrhythmia in elderly patients. Aims of this study were to evaluate the predictors of arterial stiffness after external cardioversion (ECV) of AF and to establish whether a link exists between vascular properties and left atrial diameter (LAD).

METHODS

We studied 33 patients (age 73 ± 12 years). After 5 h from ECV of persistent AF, an echocardiogram was recorded and arterial stiffness was evaluated with cardio-ankle vascular stiffness index (CAVI).

RESULTS

In multivariate analysis (R = 0.538, p = 0.006), CAVI (mean 9.60 ± 1.63) increased with age (p = 0.018) and with an AF length ≤3 months (p = 0.022). LAD was significantly related to CAVI (p = 0.007) even after adjustment for interventricular septum thickness (p = 0.018) (R = 0.574, p = 0.002).

CONCLUSIONS

In patients with AF, immediately after ECV, arterial stiffness is associated with age and AF length, and could represent an important factor for left atrium remodeling and, therefore, for AF maintenance.

Arterial stiffness determined according to the cardio-ankle vascular index is associated with paroxysmal atrial fibrillation: a cross-sectional study

BACKGROUND

Several lines of evidence suggest that atrial fibrillation (AF) may be a consequence of vascular disease. We investigated the relationship between cardio-ankle vascular index (CAVI), a new index of arterial stiffness, and the presence of paroxysmal AF (PAF).

METHODS AND RESULTS

181 outpatients (91 patients with PAF and 90 age- and gender-matched subjects without PAF) were analysed for their sinus rhythm. The CAVI was significantly higher in patients with PAF than in subjects without PAF (9.0±1.0 vs 8.7±0.8, p<0.01). In all subjects, the CAVI was significantly correlated with the left ventricular mass index (r=0.30, p<0.01), left atrial diameter (r=0.22, p<0.01), and augmentation index, a parameter of wave reflection (r=0.32, p<0.01), in addition to age, systolic blood pressure and pulse pressure. Logistic analysis demonstrated that the CAVI was independently associated with PAF even after adjustment for confounding factors. The adjusted OR of PAF was 1.8 for each unit increase in the CAVI (p=0.01).

CONCLUSIONS

Our finding suggests that increased arterial stiffness may be involved in the maintenance of AF.

Predictive value of atrial high-rate episodes for arterial stiffness and endothelial dysfunction in dual-chamber pacemaker patients

BACKGROUND

Various pacing studies have demonstrated an association between right ventricular pacing (RVp) and atrial fibrillation (AF), even after preserving atrioventricular (AV) synchrony. We aimed to assess the interaction between arterial stiffness, endothelial function and atrial high-rate episodes (AHRE) in patients with dual-chamber pacemakers.

METHODS

We studied 101 patients with dual-chamber pacemakers incorporated with sophisticated AF detection and therapy algorithms. Macrovascular endothelial dysfunction (ED) was measured by the relative change in aortic augmentation index (AIx), using carotid artery applanation tonometry in response to inhaled salbutamol and sublingual glyceryl trinitrate. Microvascular ED was measured by cutaneous laser Doppler flowmetry (LDF) in response to acetylcholine (Ach, endothelium dependent) and sodium nitroprusside (SNP, endothelium independent). Arterial stiffness was measured using carotid-femoral pulse wave velocity (PWVcf). 'Reservoir pressure' (Pr, MATLAB) describes the aortic 'cushioning' properties.

RESULTS

Mean age of the cohort was 72.1 ± 10.8 years; men (n = 69) 68.3%. Of 101 dual-chamber pacemaker patients, 23.8% (n = 24) had AHRE detected on the baseline pacemaker interrogation. PP, PWVcf and Pr were significantly higher in patients with AHRE compared with those without AHRE. The change in AIx with salbutamol (∆% AIx Sal) and acetylcholine-induced changes in LDF (Δ%LDF Ach) were lower in patients with AHRE compared with those without AHRE. In patients with AHRE, significant correlations were observed between%Vp and Δ%LDF Ach (P = 0.03) as well as between PP and Δ%LDF Ach (P = 0.05). On multivariate analysis, PP, Pr, PWVcf and ∆% AIx Sal remained as independent predictors of AHRE.

CONCLUSION

In patients with dual-chamber pacemakers, both higher arterial stiffness and greater endothelial dysfunction independently predicted AHRE, irrespective of the degree (or mode) of pacing. Arterial stiffness and endothelial dysfunction may potentially contribute to the perpetuation of atrial arrhythmias beyond the adverse effects of ventricular pacing alone.

Arterial stiffness, body fat compartments, central hemodynamics, renal function and left atrial size

BACKGROUND

Left atrial (LA) size is an important predictor of stroke, death, and atrial fibrillation. It was demonstrated recently that body fat, arterial stiffness and renal functions are associated with LA diameter. However, data are lacking for comprehensive assessments of all these risk factors in a single population. Therefore, the aim of the present study was to investigate the association between LA size and different fat descriptors, central hemodynamics, arterial stiffness, and renal function in healthy subjects.

METHODS

To this end, body fat percentage, abdominal, subcutaneous fat, and general descriptors of body fat were estimated in 162 healthy subjects (mean age 51 years). Echocardiography was performed to assess LA diameter. Arterial stiffness and peripheral and central hemodynamics were estimated by digital volume pulse analysis and pulse wave analysis. Glomerular filtration rate was estimated by MDRD formula.

RESULTS

There were significant (p < 0.05) bivariate correlations between LA diameter and all descriptors of body fat (except subcutaneous fat). Arterial stiffness and estimated glomerular filtration rate (eGFR) were also significantly correlated with LA size. Multiple regression analysis including all significant confounders, such as sex, mean arterial pressure, arterial stiffness, eGFR and body fat descriptors, explained 35% of variance in LA diameter.

CONCLUSIONS

In conclusion, the present study reveals significant, independent relationships between body fat, arterial stiffness, and LA size.

Left atrium volume index is influenced by aortic stiffness and central pulse pressure in type 2 diabetes mellitus patients: a hemodynamic and echocardiographic study

BACKGROUND

Left atrial volume index (LAVI) has recently emerged as a useful biomarker for risk stratification and risk monitoring in many clinical settings. Many hemodynamic factors such as preload and afterload have an effect on evaluating left atrium function. This study was performed to investigate the relationship between LAVI and aortic stiffness index (ASI) and selected markers characterizing hemodynamic state in patients with type 2 diabetes mellitus (DM2).

MATERIAL AND METHODS

The study population consisted of 100 patients (56 men, 44 women), 67.2 (±10.9) years old DM2, scheduled for routine coronary angiography. Standard transthoracic echocardiography was used to measure parameters needed for calculation of LAVI and ASI. During invasive procedures, central pulse pressure (CPP) in the ascendens aorta and left ventricle end-diastolic pressure (LVEDP) were recorded. Selected laboratory parameters were obtained, including lipidogram, serum uric acid, hs-CRP, fibrinogen, cTnT, myoglobin, BNP, HbA1C, creatinine, and GFR.

RESULTS

Both LAVI and ASI were greater and CPP and LVEDP were markedly elevated in DM2 patients compared to controls. The independent predictors of LAVI were ASI (ß=0.331; p=0.011), CPP (ß=0.312; p=0.020), LVEDP (ß=0.381; p=0.006), HbA1C (ß=0.379; p=0.008), and BNP (ß=0,423; p<0,001).

CONCLUSIONS

The strong correlation between HbA1C and both LAVI and ASI is a sign of negative influence of poor glycemia control on the left ventricle diastolic function and compliance of the aorta. The independent correlation between LAVI and ASI, CPP, and LVEDP improved by association of LAVI and ASI with specific biochemical markers suggests an association between LAVI and elastic properties of the aorta, as well as CPP in DM2 patients.

Left atrial volume index and aortic stiffness index in adult hemodialysed patients--link between compliance and pressure mediated by endothelium dysfunction; a cross-sectional study

BACKGROUND

This study was performed to investigate the relationship between elastic properties of aorta and left atrium volume index (LAVI) in hemodialyzed (HD) patients.

METHODS

Study group was consisted of 73 patients (age 51,6 ± 7,6 years) treated by hemodialysis. In all patients standard echocardiography was performed. Aortic stiffness index (ASI) was calculated using formula: ASI = log (SBP/DBP)/[(Aomax-Aomin)/Aomin]. LAVI was calculated according to the formula: LAVI = [π/6 x (LAmax x LAshort x LAlong)]/m(2). Additionally several indices were calculated: left ventricle mass (LVM), left ventricle mass index (LVMI), midwall fractional shortening (mFS), endsystolic stress (ESS), mFS/ESS. Additionally the laboratory parameters including lipidogram, troponin T (cTnT), NT-proBNP and asymmetric dimethylarginine (ADMA) were measured.

RESULTS

The ASI was strong and significantly correlated with left atrium volume (LAV) and LAVI (respectively: 0,601; p < 0,001 and 0,598; p < 0,001). The ASI was independently and markedly associated with ADMA, cTnT, CRP, T-chol, and LDL-chol. The LAVI was independently and significantly correlated with NT-proBNP and cTnT.

CONCLUSIONS

There is correlation between ASI and ADMA, marker of endothelium dysfunction. There is also association between LAVI and NT-proBNP, signs of elevated left atrium pressure. The strong correlation between ASI and LAVI, improved by associations of specific biochemical markers with these echocardiographic indices, suggests there is the link between elastic properties of aorta and left atrium pressure in hemodialysed patients mediated by endothelial dysfunction.

Leg blood pressure measured in orthostatic posture is associated with left ventricular mass in normotensive subjects

BACKGROUND

Changing from a supine to an orthostatic posture is associated with substantial increments in leg blood pressure (BP) levels, which could ultimately influence the hemodynamic burden imposed on the heart. This study investigated the relationship between brachial and leg BP measurements and the left cardiac chamber's structure and assessed the role of body posture changes in this regard.

METHODS

One hundred and thirty normotensive, nondiabetic, nonsmoking, normolipemic subjects were evaluated by a clinical history, anthropometry, the analysis of metabolic parameters, echocardiography, and the measurement of BP in the arm and the calf in both supine and orthostatic positions.

RESULTS

Significant correlation coefficients between the leg BP measurements and the cardiac structure were detected, especially between the orthostatic pulse pressure (PP) and the left ventricular (LV) wall thickness (r = 0.38; P < 0.001), the orthostatic PP and the LV mass (r = 0.37; P < 0.001), and the orthostatic systolic BP (SBP) and the left atrial size (r = 0.35; P < 0.001). Stepwise and standard regression analysis adjusted for brachial BP and anthropometric and metabolic variables confirmed that the leg orthostatic PP was independently related to the LV wall thickness and mass. Moreover, the leg orthostatic SBP was associated with the left atrial dimension even after adding the LV mass to the statistical models. Finally, triglyceride levels and body surface area showed significant relationship with leg orthostatic PP and SBP, whereas brachial orthostatic PP and SBP were only associated with age and anthropometric variables.

CONCLUSIONS

Orthostatic leg BP is independently associated with the cardiac structure in normotensive subjects.