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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. [ABSTRACT FROM AUTHOR]

The photoplethysmogram (PPG) signal is widely measured by clinical and consumer devices, and it is emerging as a potential tool for assessing vascular age. The shape and timing of the PPG pulse wave are both influenced by normal vascular aging, changes in arterial stiffness and blood pressure, and atherosclerosis. This review summarizes research into assessing vascular age from the PPG. Three categories of approaches are described: 1) those which use a single PPG signal (based on pulse wave analysis), 2) those which use multiple PPG signals (such as pulse transit time measurement), and 3) those which use PPG and other signals (such as pulse arrival time measurement). Evidence is then presented on the performance, repeatability and reproducibility, and clinical utility of PPG-derived parameters of vascular age. Finally, the review outlines key directions for future research to realize the full potential of photoplethysmography for assessing vascular age. [ABSTRACT FROM AUTHOR]

Background: Mortality in hemodialysis patients still remains unacceptably high. Enhanced arterial stiffness is a known cardiovascular risk factor, and pulse wave velocity (PWV) has proven to be a valid parameter to quantify risk. Recent studies showed controversial results regarding the prognostic significance of PWV for mortality in hemodialysis patients, which may be due to methodological issues, such as assessment of PWV in the office setting (Office-PWV).Method: This study cohort contains patients from the "Risk stratification in end-stage renal disease - the ISAR study," a multicenter prospective longitudinal observatory cohort study. We examined and compared the predictive value of ambulatory 24-hour PWV (24 h-PWV) and Office-PWV on mortality in a total of 344 hemodialysis patients. The endpoints of the study were all-cause and cardiovascular mortality. Survival analysis included Kaplan-Meier estimates and Cox regression analysis.Results: During a follow-up of 36 months, a total of 89 patients died, 35 patients due to cardiovascular cause. Kaplan-Meier estimates for tertiles of 24 h-PWV and Office-PWV were similarly associated with mortality. In univariate Cox regression analysis, 24 h-PWV and Office-PWV were equivalent predictors for all-cause and cardiovascular mortality. After adjustment for common risk factors, only 24 h-PWV remained solely predictive for all-cause mortality (hazard ratio 2.51 [95% CI 1.31-4.81]; p = 0.004).Conclusions: Comparing both measurements, 24 h-PWV is an independent predictor for all-cause-mortality in hemodialysis patients beyond Office-PWV. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the presented work has been the development of an algorithm for a non-invasive, portable, easy-to-use, and affordable device for measuring systemic cardiovascular parameters such as cardiac output and peripheral resistance. The data acquisition is based on a common oscillometric measurement using an occlusive blood pressure cuff, and no additional calibration is necessary. The novel algorithm introduced here combines several simulation techniques like neural networks or differential equations, which will be explained briefly. The determination of the hemodynamical parameters is based on the idea that the ejection work of the left ventricle is subject to an optimization principle. This kind of model needs no additional external calibration and opens therefore good perspectives for non-expert use in cardiovascular risk stratification and hypertension therapy optimization. To verify the approach we present some clinical results and a relevant discussion on it, followed by a view of future work. [Copyright &y& Elsevier]

Abstract: Within the last decade the quantification of pulse wave reflections mainly focused on measures of central aortic systolic pressure and its augmentation through reflections based on pulse wave analysis (PWA). A complementary approach is the wave separation analysis (WSA), which quantifies the total amount of arterial wave reflection considering both aortic pulse and flow waves. The aim of this work is the introduction and comparison of aortic blood flow models for WSA assessment. To evaluate the performance of the proposed modeling approaches (Windkessel, triangular and averaged flow), comparisons against Doppler measurements are made for 148 patients with preserved ejection fraction. Stepwise regression analysis between WSA and PWA parameters are performed to provide determinants of methodological differences. Against Doppler measurement mean difference and standard deviation of the amplitudes of the decomposed forward and backward pressure waves are comparable for Windkessel and averaged flow models. Stepwise regression analysis shows similar determinants between Doppler and Windkessel model only. The results indicate that the Windkessel method provides accurate estimates of wave reflection in subjects with preserved ejection fraction. The comparison with waveforms derived from Doppler ultrasound as well as recently proposed simple triangular and averaged flow waves showed that this approach may reduce variability and provide realistic results. [Copyright &y& Elsevier]