Showing papers by "Tomi Laitinen published in 2013"

Axial and radial waveforms in common carotid artery: an advanced method for studying arterial elastic properties in ultrasound imaging.

Abstract: Our objective was to develop a method for studying the biomechanics of the common carotid artery (CCA) by evaluating both radial and less known axial distension of the arterial wall. We developed software capable of tracking the movements of different arterial wall layers from ultrasound recordings of CCA, and we then calculated several indices of arterial stiffness. The wide spectrum of arterial stiffness indices defined from one measurement is a unique feature of our method. The motion-tracking algorithm is based on 2-D cross-correlation enhanced with luminance optimizations. The repeatability and reproducibility of the motion tracking were evaluated by performing 10-s ultrasound recordings of left CCA twice to 19 healthy volunteers (11 women, 8 men, age 41.3 ± 14.3 y). The method revealed a biphasic axial movement of the CCA and demonstrated that the indices of arterial stiffness defined from radial movement of carotid artery are reproducible (Cronbach's α, 0.59-0.97) as well as the indices from axial movement are reproducible (Cronbach's α, -0.68 to 0.93). The good reproducibility of the motion tracking is evidence that this method of studying arterial elastic properties is adequate for in vivo studies.

Genome-wide association study pinpoints a new functional apolipoprotein B variant influencing oxidized low-density lipoprotein levels but not cardiovascular events: AtheroRemo Consortium.

Abstract: Background—Oxidized low-density lipoprotein may be a key factor in the development of atherosclerosis. We performed a genome-wide association study on oxidized low-density lipoprotein and tested th...

Baroreflex sensitivity in asymptomatic coronary atherosclerosis

Abstract: Summary Background Baroreflex sensitivity (BRS) reflects the effectiveness of cardiac parasympathetic regulation BRS becomes impaired in stable coronary artery disease (CAD) and after myocardial infarction and carries prognostic information in these patients Whether impaired BRS is found already in asymptomatic subjects, with subclinical coronary atherosclerosis, has remained elusive Methods The relationship between BRS and coronary atherosclerosis was evaluated in 31 subjects with high familial risk for CAD but without evidence of angina pectoris or myocardial ischaemia Single photon emission tomography was performed with 99mTc-sestamibi to rule out myocardial perfusion defects at rest and during exercise BRS was assessed by phenylephrine technique Coronary atherosclerosis was analysed by quantitative coronary angiography (QCA) Percentage of diameter stenosis (PDS) was calculated separately for LAD, LCX, RCA coronary arteries as well as for proximal (PROX), middle (MID) and distal (DIST) coronary artery regions; and for all coronary artery regions (global PDS) Results Baroreflex sensitivity averaged 7·8 ± 5·4 ms mmHg−1 BRS showed inverse correlation to PDS of the proximal coronary artery segments (r = −0·315; P 3 ms mmHg−1 (24 ± 7% versus 13 ± 11%, P<0·05, respectively) Conclusions Impairment of BRS was found to be associated with the severity of subclinical coronary atherosclerosis in healthy asymptomatic subjects with familial risk of CAD Asymptomatic subjects with severely blunted BRS may have advanced coronary atherosclerosis

Metabolic risk factors are associated with stiffness index, reflection index and finger skin temperature in children--Physical Activity and Nutrition in Children (PANIC) study.

Abstract: BACKGROUND: Childhood metabolic syndrome (MetS) has been found to predict adulthood MetS, type 2 diabetes and cardiovascular disease, emphasizing the early identification of children at increased risk of these diseases. Children with clustering of metabolic risk factors have been reported to have a mild arterial stiffness and endothelial dysfunction, but limited evidence is available from population-based samples of children. METHODS AND RESULTS: The associations of metabolic risk factors with arterial stiffness, tone and endothelial function were studied in 173 prepubertal children (90 girls) 6-8 years of age. MetS was assessed both by continuous MetScore and dichotomously. Stiffness index (SI), reflection index (RI) and finger skin temperature (FST) were measured before and after maximum exercise test, and percent change was calculated for RI (RI%Δ) and FST (FST%Δ). MetScore (r=0.26, P=0.001), fasting insulin (r=0.24, P=0.002), fasting triglycerides (r=0.20, P=0.009), systolic (SBP; r=0.24, P=0.002) and diastolic blood pressure (DBP; r=0.19, P=0.013) correlated with SI. MetScore (r=-0.17, P=0.024, r=0.21, P=0.006), waist circumference (r=-0.19, P=0.012, r=0.23, P=0.003) and SBP (r=-0.16, P=0.035, r=0.21, P=0.005) correlated with RI and FST. High-density lipoprotein cholesterol correlated with FST (r=-0.22, P=0.004) and FST%Δ (r=-0.24, P=0.002). RI decreased and FST increased with exercise (P<0.001). Waist circumference correlated inversely with RI%Δ in boys (r=-0.22, P=0.046) and directly with RI%Δ in girls (r=0.27, P=0.011). CONCLUSIONS: Metabolic risk factors are associated with arterial stiffness, tone and endothelial function in prepubertal children.

Need for insulin to control gestational diabetes is reflected in the ambulatory arterial stiffness index.

Abstract: The aim was to evaluate the metabolic profile in conjunction with vascular function using the ambulatory arterial stiffness index (AASI) in women with uncomplicated pregnancies and in women with gestational diabetes mellitus (GDM). Plasma glucose, lipids, HOMA –IR (homeostasis model assessment of insulin resistance) and AASI, as obtained from 24-hour ambulatory blood pressure monitoring in third trimester pregnancy and at three months postpartum, were measured in three groups of women: controls (N = 32), women with GDM on diet (N = 42) and women with GDM requiring insulin treatment (N = 10). Women with GDM had poorer glycemic control and higher HOMA-IR during and after pregnancy and their total and LDL (low density lipoprotein) cholesterol levels were significantly higher after pregnancy than in the controls. After delivery, there was an improvement in AASI from 0.26 ± 0.10 to 0.17 ± 0.09 (P = 0.002) in women with GDM on diet, but not in women with GDM receiving insulin whose AASI tended to worsen after delivery from 0.30 ± 0.23 to 0.33 ± 0.09 (NS), then being significantly higher than in the other groups (P = 0.001-0.047). Women with GDM had more unfavorable lipid profile and higher blood glucose values at three months after delivery, the metabolic profile being worst in women requiring insulin. Interestingly, the metabolic disturbances at three months postpartum were accompanied by a tendency towards arterial stiffness to increase in women requiring insulin.

Intermittent levosimendan treatment in patients with severe congestive heart failure.

Abstract: Objective Levosimendan (LS) is a novel inodilator for the treatment of severe congestive heart failure (CHF). In this study, we investigated the potential long-term effects of intermittent LS treatment on the pathophysiology of heart failure.

Causal estimation of neural and overall baroreflex sensitivity in relation to carotid artery stiffness

Abstract: Continuous electrocardiogram, blood pressure and carotid artery ultrasound video were analyzed from 15 diabetics and 28 healthy controls. By using these measurements artery elasticity, overall baroreflex sensitivity (BRS) assessed between RR and systolic blood pressure variation, and neural BRS assessed between RR and artery diameter variation were estimated. In addition, BRS was estimated using traditional and causal methods which enable separation of feedforward and feedback variation. The aim of this study was to analyze overall and neural BRS in relation to artery stiffness and to validate the causal BRS estimation method in assessing these two types of BRS within the study population. The most significant difference between the healthy and diabetic groups (p < 0.0007) was found for the overall BRS estimated using the causal method. The difference between the groups was also significant for neural BRS (p < 0.0018). However neural BRS was normal in some old diabetics, which indicates normal functioning of autonomic nervous system (ANS), even though the elasticity in arteries of these subjects was reduced. The noncausal method overestimated neural BRS in low BRS values when compared to causal BRS. In conclusion, neural BRS estimated using the causal method is proposed as the best marker of ANS functioning.