Aortic stiffness is not only associated with structural but also functional parameters of retinal microcirculation.

OBJECTIVE: The aim of the study was to test the hypothesis that alterations in large arteries are associated with microvascular remodelling and decreased retinal capillary blood flow. METHODS: The study group comprised of 88 patients with essential hypertension and 32 healthy controls. Retinal microcirculation was evaluated by scanning laser Doppler flowmetry. Macrovascular changes were assessed on the basis of arterial stiffness measurement (carotid-femoral pulse wave velocity), its hemodynamic consequences (central pulse pressure, augmentation pressure, augmentation index) and intima media thickness of common carotid artery. RESULTS: Pulse wave velocity was inversely correlated to mean retinal capillary blood flow in hypertensive patients (R = -0.32, p < 0.01). This relationship remained significant in multivariate regression analysis after adjustment for age, sex, central systolic blood pressure (BP) and body mass index (ß = -31.27, p < 0.001). Lumen diameter (LD) of retinal arterioles was significantly smaller in hypertensive then normotensive subjects (79.4 vs. 83.8, p = 0.03). Central and brachial systolic, diastolic and mean BPs were significantly correlated with LD and outer diameter of retinal arterioles. The relationship between LD and central BPs remained significant in multivariate analysis (ß = -0.15, p = 0.03 for cSBP; ß = -0.22, p = 0.04 for cDBP; ß = -0.21, p = 0.03 for cMBP). Moreover, in a subgroup with cardiac damage central and brachial pulse pressure were positively associated with retinal wall thickness, wall cross sectional area, and wall to lumen ratio. CONCLUSION: In conclusion, the study provides a strong evidence that microcirculation is coupled with macrocirculation not only in terms of structural but also functional parameters.

Lumen narrowing and increased wall to lumen ratio of retinal microcirculation are valuable biomarkers of hypertension-mediated cardiac damage.

Purpose: In the course of hypertension, left ventricular hypertrophy and diastolic dysfunction develop very often and may progress toward heart failure. The aim of the study was to analyze the relationship between abnormalities of retinal microcirculation and cardiac damage defined as left ventricular hypertrophy and/or diastolic dysfunction.Materials and methods: The study comprised 88 patients with essential hypertension. The group was divided into two subgroups: hypertensives without cardiac damage (n = 55) and with cardiac damage (n = 33). Control group comprised 32 normotensive subjects. Scanning laser Doppler flowmetry was used to evaluate retinal microcirculation. Echocardiography was used to assess cardiac damage.Results: Lumen diameter of retinal arterioles was significantly smaller in patients with cardiac damage vs. controls (77 vs. 84 µm, p = 0.02). Additionally, there was an evident trend with respect to lumen diameter (LD) across all three studied subgroups; i.e.: the smallest dimeters were present in cardiac damage patients, moderate size in hypertensives' without cardiac damage, and the largest diameters in healthy controls (pfor trend < 0.01). Lumen diameter was inversely correlated with cardiac intraventricular septum diameter (R = -0.25, p = 0.02), left ventricular mass (R = -0.24, p = 0.02), and left atrial volume (R = -0.22, p = 0.04). Wall to lumen ratio was associated with intraventricular septum diameter (R = 0.21, p = 0.044) and left atrial volume (R = 0.21, p = 0.045). In multivariable regression analysis, lumen diameter was independently associated with intraventricular septum diameter (ß = -0.05, p = 0.03), left ventricular mass (ß = -1.15, p = 0.04), and left atrial volume (ß = -0.42, p = 0.047); wall to lumen ratio was independently associated with intraventricular septum diameter (ß = 3.67, p = 0.02) and left atrial volume (ß = 30.0, p = 0.04).Conclusions: In conclusion, retinal arterioles lumen diameter and wall to lumen ratio were independent biomarkers of cardiac damage. Retinal examination performed by means of scanning laser Doppler flowmetry might be a valuable tool to improve cardiovascular risk stratification of hypertensive patients.

Left ventricular function after takotsubo is not fully recovered in long-term follow-up: A speckle tracking echocardiography study.

BACKGROUND: Complete improvement of left ventricle (LV) systolic function is an essential feature of takotsubo cardiomyopathy (TTC). It is suggested that 2-dimensional speckle tracking echocardiography (2D STE) can evaluate LV dysfunction more accurately than conventional echocardiography. Thus, the purpose of this research was to assertain whether LV function recovery is complete after the acute phase of TTC using 2D STE commencing 6 to 9 months after discharge. METHODS: Thirty patients (29 females, 67 ± 11 years) with an apical ballooning TTC pattern 225.5 ± 27.4 days after their index event were enrolled. The control group consisted of 20 (19 females, 64 ± 9 years) age- and sex-matched volunteers without structural heart disease. Classic echocardiographic parameters, longitudinal strain and LV twist parameters were assessed and compared between the groups. RESULTS: There were no differences in traditional LV systolic, diastolic parameters and in global peak longitudinal strain. In comparison to controls, patients with TTC had lower mean apical rotation (14.4° ± 6.5° vs. 18.3° ± 6.7°; p = 0.048), slower mean peak early diastolic apical rotation rate (-85.1-°/s ± 40.9-°/s vs -119.4-°/s ± 41.9-°/s; p = 0.006) and higher pre-stretch index in the apex (2.16, IQR 0.33-5.50 vs. 0.00, IQR 0.00-2.95, p = 0.008). CONCLUSIONS: The improvement of LV function in patients with TTC as assessed by 2D STE may not always be complete. Some residual abnormalities in LV apex function were observed in long-term recovery following TTC episodes.

Left ventricular ejection fraction and aortic stiffness are independent predictors of neurological outcome in acute ischemic stroke.

BACKGROUND: Stroke is a leading cause of disability and one of the major causes of death worldwide. The short-term prognosis in individual patients is highly variable and cannot be explained solely by stroke severity. We investigated the association of left ventricular ejection fraction with early neurological outcome in acute ischemic stroke. METHODS: In total, 216 patients enrolled in a prospective study, underwent echocardiography and applanation tonometry performed within 1 week after stroke onset. At day 10, favorable outcome was defined as a 4 or more point improvement from baseline National Institutes of Health Stroke Scale or final National Institutes of Health Stroke Scale of 0-1. RESULTS: In patients with favorable outcome, the ejection fraction was significantly higher comparing with patients with poorer prognosis (54.3 ±â€Š7.9 vs. 49.9 ±â€Š9.8%, P = 0.005). Favorable neurological outcome at day 10 was also associated with lower heart rate and lower pulse wave velocity at baseline. Univariate analyses showed that left ventricle ejection fraction and arterial stiffness were the strongest predictors of the poststroke improvement. In multivariate analysis, ejection fraction at least 50% remained significantly associated with favorable outcome after full adjustment for potential confounders (odds ratio 3.81, [95% confidence interval, 1.18-12.35]; P = 0.02). CONCLUSION: These findings provide evidence that in ischemic stroke, preserved ejection fraction and lower pulse wave velocity are associated with early favorable outcome, independently of other known prognostic factors, including blood pressure.

Acute hypertensive response in ischemic stroke is associated with increased aortic stiffness.

BACKGROUND AND AIMS: Acute hypertensive response (AHR) affects more than 60% of patients with ischemic stroke and is associated with poor outcomes. We hypothesized that its development is related to arterial stiffening. "The gold standard" estimate of arterial stiffness is carotid-femoral pulse wave velocity (CF-PWV). We compared CF-PWV and indirect indices of arterial stiffness (central augmentation index (cAIxHR), central systolic (cSBP) and pulse (cPP) pressures) between acute ischemic stroke patients who developed AHR and those who were normotensive in the early phase of stroke. METHODS: AHR was assessed through hourly BP measurements within 24 h from admission using an oscillometric device. The stiffness was assessed using applanation tonometry with a SphygmoCor(®) device (Atcor, Sydney, Australia) 7 ± 2 days after stroke. RESULTS: Among 102 patients with acute ischemic stroke, 73(71.5%) met AHR criteria. In an univariate analysis, CF-PWV, cAIxHR, cSBP and cPP were higher in those who developed AHR (10.9 vs. 8.3 m/s, p < 0.001; 30.8 vs. 23.9%, p = 0.004; 138.2 vs. 117.2 mmHg, p < 0.001; 54.6 vs. 44 mmHg, p = 0.005, respectively). In a multivariate logistic regression analysis, CF-PWV was independently associated with AHR after adjustment for age and peripheral mean blood pressure (pMBP) (p = 0.04), for age, pMBP and diabetes mellitus (DM) (p = 0.045), and age, pMBP, DM and hypertension (p = 0.047). CONCLUSION: This study revealed for the first time that AHR in ischemic stroke is associated with elevated aortic stiffness independently of other clinical factors including age and hypertension preceding stroke. A potential pathophysiological mechanism responsible for this relationship includes impaired baroreceptor function in stiff arteries resulting in impaired BP autoregulation.

Heart rate variability and functional outcome in ischemic stroke: a multiparameter approach.

BACKGROUND AND PURPOSE: Heart rate variability (HRV) as a measure of autonomic function might provide prognostic information in ischemic stroke. However, numerous difficulties are associated with HRV parameters assessment and interpretation, especially in short-term ECG recordings. For better understanding of derived HRV data and to avoid methodological bias we simultaneously recorded and analyzed heart rate, blood pressure and respiratory rate. METHODS: Seventy-five ischemic stroke patients underwent short-term ECG recordings. Linear and nonlinear parameters of HRV as well as beat-to-beat blood pressure and respiratory rate were assessed and compared in patients with different functional neurological outcomes at 7th and 90th days. RESULTS: Values of Approximate, Sample and Fuzzy Entropy were significantly lower in patients with poor early neurological outcome. Patients with poor 90-day outcome had higher percentage of high frequency spectrum and normalized high frequency power, lower normalized low frequency power and lower low frequency/high frequency ratio. Low frequency/high frequency ratio correlated negatively with scores in the National Institutes of Health Stroke Scale and modified Rankin Scale (mRS) at the 7th and mRS at the 90th days. Mean RR interval, values of blood pressure as well as blood pressure variability did not differ between groups with good and poor outcomes. Respiratory frequency was significantly correlated with the functional neurological outcome at 7th and 90th days. CONCLUSION: While HRV assessed by linear methods seems to have long-term prognostic value, complexity measures of HRV reflect the impact of the neurological state on distinct, temporary properties of heart rate dynamic. Respiratory rate during the first days of the stroke is associated with early and long-term neurological outcome and should be further investigated as a potential risk factor.

Pulse wave velocity is associated with early clinical outcome after ischemic stroke.

BACKGROUND AND PURPOSES: Pulse wave analysis (PWV), a marker of aortic stiffness, has independent predictive value for cardiovascular morbidity and mortality in both healthy and high-risk populations, especially fatal stroke, and for long-term functional stroke prognosis. Whether arterial stiffness and wave reflection are related to stroke in-hospital short-term outcome has never been demonstrated. METHODS: In a prospective study, we enrolled 134 patients with acute ischemic stroke, aged 63.4 ± 12.5 years, mean ± SD, National Institutes of Health stroke scale (NIHSS) scored 7.1 ± 6.5 at admission. Carotid-femoral (CF) PWV and central augmentation index (cAIx) were measured (SphygmoCor) one week after stroke onset. At hospital discharge, favorable outcome was defined as a 4 or more point improvement from baseline NIHSS or NIHSS of 0-1. Data were analyzed with logistic regression. RESULTS: In univariate analysis, low CF-PWV (P = 0.000,001), but not cAIx, was significantly associated with early favorable outcome. In multivariate analysis, CF-PWV > 9.0 m/s remained significantly associated with favorable early outcome after adjustment for age, NIHSS and blood glucose level on admission, as well as heart rate, systolic and mean blood pressure, measured at day 7 (OR = 0.17 [95% CI, 0.05-0.60];P = 0.006). CONCLUSIONS: In ischemic stroke, low aortic stiffness (CF-PWV) is associated with early favorable outcome, independently of other known prognostic factors.

Aortic stiffness predicts functional outcome in patients after ischemic stroke.

BACKGROUND AND PURPOSE: Increased aortic stiffness (measured by carotid-femoral pulse wave velocity) and central augmentation index have been shown to independently predict cardiovascular events, including stroke. We studied whether pulse wave velocity and central augmentation index predict functional outcome after ischemic stroke. METHODS: In a prospective study, we enrolled 99 patients with acute ischemic stroke (age 63.7 ± 12.4 years, admission National Institutes of Health Stroke Scale score 6.6 ± 6.6, mean ± SD). Carotid-femoral pulse wave velocity and central augmentation index (SphygmoCor) were measured 1 week after stroke onset. Functional outcome was evaluated 90 days after stroke using the modified Rankin Scale with modified Rankin Scale score of 0 to 1 considered an excellent outcome. RESULTS: In univariate analysis, low carotid-femoral pulse wave velocity (P=0.000001) and low central augmentation index (P=0.028) were significantly associated with excellent stroke outcome. Age, severity of stroke, presence of previous stroke, diabetes, heart rate, and peripheral pressures also predicted stroke functional outcome. In multivariate analysis, the predictive value of carotid-femoral pulse wave velocity (<9.4 m/s) remained significant (OR, 0.21; 95% CI, 0.06-0.79; P=0.02) after adjustment for age, National Institutes of Health Stroke Scale score on admission, and presence of previous stroke. By contrast, central augmentation index had no significant predictive value after adjustment. CONCLUSIONS: This study indicates that aortic stiffness is an independent predictor of functional outcome in patients with acute ischemic stroke.