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Concept: Systole


Regular exercise training improves maximal oxygen uptake (VO2max), but the optimal intensity and volume necessary to obtain maximal benefit remains to be defined. A growing body of evidence suggests that exercise training with low-volume but high-intensity may be a time-efficient means to achieve health benefits. In the present study, we measured changes in VO2max and traditional cardiovascular risk factors after a 10 wk. training protocol that involved three weekly high-intensity interval sessions. One group followed a protocol which consisted of 4×4 min at 90% of maximal heart rate (HRmax) interspersed with 3 min active recovery at 70% HRmax (4-AIT), the other group performed a single bout protocol that consisted of 1×4 min at 90% HRmax (1-AIT). Twenty-six inactive but otherwise healthy overweight men (BMI: 25-30, age: 35-45 y) were randomized to either 1-AIT (n = 11) or 4-AIT (n = 13). After training, VO2max increased by 10% (∼5.0 mL⋅kg(-1)⋅min(-1)) and 13% (∼6.5 mL⋅kg(-1)⋅min(-1)) after 1-AIT and 4-AIT, respectively (group difference, p = 0.08). Oxygen cost during running at a sub-maximal workload was reduced by 14% and 13% after 1-AIT and 4-AIT, respectively. Systolic blood pressure decreased by 7.1 and 2.6 mmHg after 1-AIT and 4-AIT respectively, while diastolic pressure decreased by 7.7 and 6.1 mmHg (group difference, p = 0.84). Both groups had a similar ∼5% decrease in fasting glucose. Body fat, total cholesterol, LDL-cholesterol, and ox-LDL cholesterol only were significantly reduced after 4-AIT. Our data suggest that a single bout of AIT performed three times per week may be a time-efficient strategy to improve VO2max and reduce blood pressure and fasting glucose in previously inactive but otherwise healthy middle-aged individuals. The 1-AIT type of exercise training may be readily implemented as part of activities of daily living and could easily be translated into programs designed to improve public health.

Concepts: Blood, Myocardial infarction, Atherosclerosis, Blood pressure, Artery, Pulse, Cardiac cycle, Systole


OBJECTIVES: The purpose of this study was to examine the impact of yoga on atrial fibrillation (AF) burden, quality of life (QoL), depression, and anxiety scores. BACKGROUND: Yoga is known to have significant benefit on cardiovascular health. The effect of yoga in reducing AF burden is unknown. METHODS: This single-center, pre-post study enrolled patients with symptomatic paroxysmal AF with an initial 3-month noninterventional observation period followed by twice-weekly 60-min yoga training for next 3 months. AF episodes during the control and study periods as well as SF-36, Zung self-rated anxiety, and Zung self-rated depression scores at baseline, before, and after the study phase were assessed. RESULTS: Yoga training reduced symptomatic AF episodes (3.8 ± 3 vs. 2.1 ± 2.6, p < 0.001), symptomatic non-AF episodes (2.9 ± 3.4 vs. 1.4 ± 2.0; p < 0.001), asymptomatic AF episodes (0.12 ± 0.44 vs. 0.04 ± 0.20; p < 0.001), and depression and anxiety (p < 0.001), and improved the QoL parameters of physical functioning, general health, vitality, social functioning, and mental health domains on SF-36 (p = 0.017, p < 0.001, p < 0.001, p = 0.019, and p < 0.001, respectively). There was significant decrease in heart rate, and systolic and diastolic blood pressure before and after yoga (p < 0.001). CONCLUSIONS: In patients with paroxysmal AF, yoga improves symptoms, arrhythmia burden, heart rate, blood pressure, anxiety and depression scores, and several domains of QoL. (Yoga on Arrythmia Burden and Quality of Life in Paroxysmal Atrial Fibrillation; NCT00798356).

Concepts: Blood, Heart, Stroke, Atrial fibrillation, Blood pressure, Ventricle, Cardiac cycle, Systole


Observational studies support that dairy product intake is associated with a reduced risk of developing type 2 diabetes; however, several clinical studies report conflicting results on the association between dairy product consumption and metabolic parameters. The aim of this study was to determine associations between dairy product consumption and metabolic profile. Dietary data, using a validated food frequency questionnaire, and fasting blood samples were collected from 233 French Canadians. Plasma phospholipid (PL) fatty acids (FA) concentrations were determined by gas chromatography. Subjects consumed 2.5 ± 1.4 portions of dairy products daily, including 1.6 ± 1.3 portions of low-fat (LF) and 0.90 ± 0.70 portions of high-fat (HF) dairy products. Trans-palmitoleic acid level in plasma PL was related to HF dairy consumption (r = 0.15; p = 0.04). Total (r = -0.21; p = 0.001) and LF dairy (r = -0.20; p = 0.003) intakes were inversely correlated with fasting plasma glucose level. Total dairy intake was inversely associated to systolic blood pressure (r = -0.17; p = 0.008) and diastolic blood pressure (r = -0.14; p = 0.03). LF dairy intake was also inversely correlated with systolic blood pressure (r = -0.17; p = 0.009). Total dairy intake was correlated with plasma C-reactive protein (CRP) (r = 0.15; p = 0.03). No association was found between HF dairy consumption and the risk factors studied. In conclusion, dairy intake is inversely associated with glycaemia and blood pressure; yet, it may modify CRP levels. Moreover, trans-palmitoleic FA levels in plasma PL may be potentially used to assess full-fat dairy consumption.

Concepts: Protein, Nutrition, Blood, Hypertension, Blood pressure, Artery, C-reactive protein, Systole


Central aortic systolic blood pressure (SBP-C) can be estimated from a cuff oscillometric waveform derived during the pulse volume plethysmography (PVP) by applying a device-specific aortic pressure-to-PVP waveform-generalized transfer function (A2P(GTF)). The present study compared the performance of an aortic-to-brachial pressure waveforms generalized transfer function (A2B(GTF)), which is independent of any PVP devices, with an A2P(GTF). Generalized transfer function of aortic-to-brachial (A2B(GTF)) and aortic-to-PVP (A2P(GTF)) were generated from the simultaneously obtained central aortic and brachial pressure waveforms recorded by a high-fidelity dual pressure sensor catheter, and the PVP waveform recorded by a customized noninvasive blood pressure monitor during cardiac catheterization in 40 patients, and were then applied in another 100 patients with simultaneously recorded invasive aortic pressure and noninvasively calibrated (using cuff SBP and diastolic blood pressures) PVP waveforms. The mean difference±s.d. between the noninvasively estimated and invasively recorded SBP-C was -2.1±7.7 mm Hg for A2B(GTF), which was not greater than that of -3.0±7.7 mm Hg for A2P(GTF) (P<0.01). In conclusion, SBP-C can be measured reliably using a noninvasive blood pressure monitor by applying either an A2P(GTF) or A2B(GTF) to a noninvasively calibrated PVP waveform. The performance of an A2B(GTF) is not inferior to that of an A2P(GTF).

Concepts: Blood pressure, Artery, Pulse, Ventricle, Cardiac cycle, Systole, Brachial artery, Sphygmomanometer


Objectives: Specific Health Examinations and Guidance (Tokutei kenko shinsa/Tokutei hoken shido) are provided for people over 40 years of age to reduce the incidence of metabolic syndrome (MetS). In the present study, we evaluated the importance of weight control in people below 40 years of age. Methods: Male subjects (n=877), aged 30 years, without MetS, were examined. Subjects were classified into 3 groups based on body mass index (BMI): non-obese (BMI<22), pre-obese (22≤BMI<25), and obese (BMI≥25). Cox proportional hazards regression analysis was performed for each group to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of MetS in individuals in their 40s on the basis of changes in their BMI, systolic blood pressure, diastolic blood pressure, fasting plasma glucose, high-density lipoprotein, and triglyceride levels between 30 and 35 years of age. In addition, subjects were classified into 3 sub-groups based on changes in BMI: stable-decrease (BMI change <1), slight increase (1≤BMI increase <2), and increase (2≤BMI increase). HRs for the 3 BMI change sub-groups for MetS were calculated for non-obese and pre-obese subjects. Results: There was a significant association between changes in BMI and the incidence of MetS for non-obese individuals in their 40s (HR: 2.80, 95% CI: 1.61-4.88) and pre-obese subjects (HR: 2.00, 95% CI: 1.44-2.77). There were also significant associations between the stable/decrease and increase (HR: 9.39, 95% CI: 1.52-57.70) sub-groups and MetS in the non-obese group, as well as for the slight increase (HR: 2.30, 95% CI: 1.03-5.11) and increase (HR: 10.13, 95% CI: 4.30-23.80) sub-groups in the pre-obese group. Conclusion: BMI change in young adults is an important risk factor for MetS among individuals in their 40s. Even subjects with a BMI lower than 25 had differences in the risk of developing MetS based on their BMI change sub-group. In the field of occupational health, it will be necessary to promote stable weight control in young adults to reduce the incidence of MetS.

Concepts: Nutrition, Atherosclerosis, Hypertension, Obesity, Blood pressure, Mass, Body mass index, Systole


Objective: The present study was planned to study comparative effects of telmisartan vs lisinopril on blood pressure in patients of metabolic syndrome Methods: The study was carried out on 62 patients of metabolic syndrome from Dec 2010 to Oct 2012 in OPD of Institute. There were two groups, A and B. Group A- Telmisartan (31 patients) and Group B- Lisinopril (31 patients) receiving Telmisartan 40 mg and lisinopril 5 mg orally once a day respectively for 12 weeks. The diagnosis of essential hypertension was made by the physician based on two measurement of blood pressure on two different occasions using auscultatory method and was done at initial stage and repeated after 6 weeks and 12 weeks of treatment in Group A and Group B patients. Key findings: Our study found that telmisartan or lisinopril treatment for 12 weeks leads to statistically significant (p<0.001) reduction in both SBP and DBP at 6 and 12 weeks when compared with baseline, whereas comparison between telmisartan and lisinopril treatment failed to show any statistically significant effect. Conclusion: Treatment of metabolic patients with telmisartan or lisinopril for management of hypertension reduced both Systolic blood pressure (SBP) as well as Diastolic blood pressure (DBP) statistically significantly during 12 weeks treatment. However, telmisartan and lisinopril treatment found effective.

Concepts: Atherosclerosis, Hypertension, Blood pressure, Artery, Orthostatic hypotension, Prehypertension, Cardiac cycle, Systole


Despite improved surgical techniques, preoperative and postoperative care, patients with functionally univentricular hearts (UVH) continue to have high morbidity and mortality and a decreased lifespan. Ventricular systolic and diastolic dysfunction is a major contributing factor to Fontan patient outcome. The evaluation of ventricular function in patients with UVH is particularly challenging. At a cellular and ultrastructural level, there are inherent differences between single and biventricular right and left ventricles. In addition, there are variable loading conditions throughout the stages of single ventricle palliation as well as variable ventricular remodelling in response to these changes. We will discuss the traditional and newer, advanced echocardiographic techniques that have been applied to evaluate ventricular function in patients with UVH. Each method has inherent advantages and disadvantages when applied to this population. The use of novel techniques including deformational imaging and 3-dimensional echocardiography will hopefully provide a more comprehensive understanding of the performance of the single ventricle, and how ventricular dysfunction affects the clinical status of patients after Fontan palliation.

Concepts: Cardiology, Heart, Blood pressure, Ventricle, Programming language, Systole, Ventricular system, Diastole


4D Flow MRI has been used to quantify normal and deranged left ventricular blood flow characteristics on the basis of functionally distinct flow components. However, the application of this technique to the atria is challenging due to the presence of continuous inflow. This continuous inflow necessitates plane-based emission of particle traces from the inlet veins, leading to particles that represents different amounts of blood, and related quantification errors. The purpose of this study was to develop a novel fixed-volume approach for particle tracing and employ this method to develop quantitative analysis of 4D blood flow characteristics in the left atrium. 4D Flow MRI data were acquired during free-breathing using a navigator-gated gradient-echo sequence in three volunteers at 1.5T. Fixed-volume particle traces emitted from the pulmonary veins were used to visualize left atrial blood flow and to quantitatively separate the flow into two functionally distinct flow components: Direct flow=particle traces that enter and leave the atrium in one heartbeat, Retained flow=particle traces that enter the atrium and remains there for one cardiac cycle. Flow visualization based on fixed-volume traces revealed that, beginning in early ventricular systole, flow enters the atrium and engages with residual blood volume to form a vortex. In early diastole during early ventricular filling, the organized vortical flow is extinguished, followed by formation of a second transient atrial vortex. Finally, in late diastole during atrial contraction, a second acceleration of blood into the ventricle is seen. The direct and retained left atrial flow components were between 44 and 57% and 43-56% of the stroke volume, respectively. In conclusion, fixed-volume particle tracing permits separation of left atrial blood flow into different components based on the transit of blood through the atrium.

Concepts: Blood, Heart, Blood pressure, Circulatory system, Ventricle, Atrium, Systole, Diastole


The current review clarifies the cardiometabolic health effects of high-intensity interval training (HIIT) in adults. A systematic search (PubMed) examining HIIT and cardiometabolic health markers was completed on 15 October 2015. Sixty-five intervention studies were included for review and the methodological quality of included studies was assessed using the Downs and Black score. Studies were classified by intervention duration and body mass index classification. Outcomes with at least 5 effect sizes were synthesised using a random-effects meta-analysis of the standardised mean difference (SMD) in cardiometabolic health markers (baseline to postintervention) using Review Manager 5.3. Short-term (ST) HIIT (<12 weeks) significantly improved maximal oxygen uptake (VO2 max; SMD 0.74, 95% CI 0.36 to 1.12; p<0.001), diastolic blood pressure (DBP; SMD -0.52, 95% CI -0.89 to -0.16; p<0.01) and fasting glucose (SMD -0.35, 95% CI -0.62 to -0.09; p<0.01) in overweight/obese populations. Long-term (LT) HIIT (≥12 weeks) significantly improved waist circumference (SMD -0.20, 95% CI -0.38 to -0.01; p<0.05), % body fat (SMD -0.40, 95% CI -0.74 to -0.06; p<0.05), VO2 max (SMD 1.20, 95% CI 0.57 to 1.83; p<0.001), resting heart rate (SMD -0.33, 95% CI -0.56 to -0.09; p<0.01), systolic blood pressure (SMD -0.35, 95% CI -0.60 to -0.09; p<0.01) and DBP (SMD -0.38, 95% CI -0.65 to -0.10; p<0.01) in overweight/obese populations. HIIT demonstrated no effect on insulin, lipid profile, C reactive protein or interleukin 6 in overweight/obese populations. In normal weight populations, ST-HIIT and LT-HIIT significantly improved VO2 max, but no other significant effects were observed. Current evidence suggests that ST-HIIT and LT-HIIT can increase VO2 max and improve some cardiometabolic risk factors in overweight/obese populations.

Concepts: Blood pressure, Artery, Pulse, Meta-analysis, Cardiac cycle, Systole, High-intensity interval training, VO2 max


BACKGROUND/OBJECTIVES:Hypertension affects about 30% of adults worldwide. Garlic has blood pressure-lowering properties and the mechanism of action is biologically plausible. Our trial assessed the effect, dose-response, tolerability and acceptability of different doses of aged garlic extract as an adjunct treatment to existing antihypertensive medication in patients with uncontrolled hypertension.SUBJECTS/METHODS:A total of 79 general practice patients with uncontrolled systolic hypertension participated in a double-blind randomised placebo-controlled dose-response trial of 12 weeks. Participants were allocated to one of three garlic groups with either of one, two or four capsules daily of aged garlic extract (240/480/960 mg containing 0.6/1.2/2.4 mg of S-allylcysteine) or placebo. Blood pressure was assessed at 4, 8 and 12 weeks and compared with baseline using a mixed-model approach. Tolerability was monitored throughout the trial and acceptability was assessed at 12 weeks by questionnaire.RESULTS:Mean systolic blood pressure was significantly reduced by 11.8±5.4 mm Hg in the garlic-2-capsule group over 12 weeks compared with placebo (P=0.006), and reached borderline significant reduction in the garlic-4-capsule group at 8 weeks (-7.4±4.1 mm Hg, P=0.07). Changes in systolic blood pressure in the garlic-1-capsule group and diastolic blood pressure were not significantly different to placebo. Tolerability, compliance and acceptability were high in all garlic groups (93%) and highest in the groups taking one or two capsules daily.CONCLUSIONS:Our trial suggests aged garlic extract to be an effective and tolerable treatment in uncontrolled hypertension, and may be considered as a safe adjunct treatment to conventional antihypertensive therapy.European Journal of Clinical Nutrition advance online publication, 21 November 2012; doi:10.1038/ejcn.2012.178.

Concepts: Myocardial infarction, Hypertension, Blood pressure, Artery, Ventricle, Orthostatic hypotension, Prehypertension, Systole