Adjustment For Heart Rate Research Articles

Assessment of the QT interval in right bundle branch block

Background Identifying prolonged QT interval in RBBB has been problematic. Methods Four approaches were compared to adjust for the QT prolongation in intermittent RBBB. The implications were assessed in a separate group of 200 persons with established RBBB. Results In 12 individuals, mean age 74.5 years with intermittent RBBB, the presence of RBBB significantly (p < 0.05) increased the QT interval in each of six different heart rate correction formulae by an amount ranging from 35.4 ms in the Hodges formula to 50.2 ms in the Bazett formula. Four different equations were tested to adjust the QT interval and one approach QTcRBBB = 0.945*QTcRBBB − 26 was the best method to adjust for the increased QT in RBBB as it produced a QT value that was not significantly different from the QT interval in the absence of RBBB in intermittent RBBB. Failure to adjust the QT interval in RBBB produces an overestimate of the QT interval which in some heart rate adjustment formulae was marked. For the Bazett heart rate adjustment approach QTc 450 ms was found in 73.9% of men and QTc over 460 ms was found in 60.6% of women. Conclusion These data suggest the implementation of a new approach to recalculate the QT intervals in RBBB. QTcRBBB = 0.945*QTcRBBB − 26 with an appropriate heart rate adjustment formula (other than the Bazett formula) accurately predicts the QT interval in the absence of RBBB.

Cardiorespiratory fitness but not physical activity are associated with pulse wave velocity and arterial stiffness in the general population

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): BMBF Background Higher cardiorespiratory fitness (CRF) and physical activity (PA) are associated with lower cardiovascular morbidity and all-cause mortality. Pulse wave velocity (PWV) and augmentation index (AIx) are vascular parameters associated with aging and end-organ damage and provide reliable information about arterial stiffness. Therefore, PWV and AIx could represent attractive parameters for cardiovascular risk stratification. Purpose To improve our understanding of the relationship between CRF/PA and PWV and arterial stiffness, we associated CRF and PA with central and peripheral PWVs and AIx as outcomes using multivariable regression analysis using data from the population-based Study of Health in Pomerania (SHIP Trend 1). Methods CRF was assessed using cardiopulmonary exercise testing (CPET) on a bicycle ergometer. CRF was defined as peak oxygen uptake (VO2peak), VO2peak per kg fat free mass (VO2peak_ffm) and metabolic equivalent tasks (METs). PA was measured using the Baecke questionnaire. Aortic PWV (aoPWV), carotid-femoral PWV (cfPWV) and brachial-ankle PWV (baPWV) in m/s were determined non-invasively using the Vascular Explorer. Aortic AIx (aoAIx), aortic AIx at a heart rate of 75 bpm (aoAIx@75) and brachial-ankle AIx (brAIx) were measured using the same device. We used linear regression models adjusted for age, sex, smoking status, mean arterial pressure, antihypertensive medication, diabetic medication, HbA1c, fat mass, fat-free-mass and height. Fat-free mass was not included when VO2peak_ffm was the exposure. Fat-free mass and fat mass were not used in models with METs. Results We analysed data of 1,677 individuals which included 840 men (median age 56 years; inter-quartile range [IQR] 47 to 65) and 837 women (median age 54 years; IQR 46 to 65). A one l/min greater VO2peak was related to lower aoPWV (β - 0.22; 95% confidence interval (CI) -0.37 to -0.06, p &amp;lt; 0.01), cfPWV (β - 0.32; 95%CI -0.55 to -0.09; p &amp;lt; 0.01), baPWV (β -0.02; 95%CI -0.03 to 0.00, p &amp;lt; 0.05) and brAIx (β -3.49; 95%CI -6.95 to -0.03, p &amp;lt; 0.01). VO2peak was not related to aoAIx and aoAIx@75. VO2peak_ffm was associated with lower aoPWV (β -0.01; 95%CI -0.02 to -0.00, p &amp;lt; 0.05) and cfPWV (β -0.02; 95%CI -0.03 to -0.00, p &amp;lt; 0.05). VO2peak_ffm was not associated with baPWV, aoAIx, aoAIx@75 or brAIx. METs were positively associated with aoAIx@75 (β 0.30; 95%CI 0.02 to 0.59, p &amp;lt; 0.01). Sport and work related PA were not related to PWV or AIx. Sensitivity analysis with further adjustment for heart rate did not significantly change the results. Conclusions We found an association between CRF and central as well as peripheral PWV and AIx values in the adult general population. Interestingly, body composition had an impact on the relationship between CRF and peripheral but not central parameters. Further, PA was not related to these vascular markers which highlights the important difference between CRF and PA.

Increased carotid artery stiffness after preeclampsia in a cross-sectional study of postpartum women.

Preeclampsia (PE) is a hypertensive obstetrical complication associated with increased cardiovascular disease risk. Carotid artery functional assessments allow for identification of subclinical vascular dysfunction. This cross‐sectional study measured carotid artery functional indices in healthy women with a recent pregnancy complicated by PE, versus women with a prior uncomplicated pregnancy. Women with a history of PE (N = 30) or an uncomplicated pregnancy (N = 30), were recruited between 6 months and 5 years postpartum. Left and right carotid artery ultrasound measured carotid intima media thickness, plaque burden, peak systolic velocity, end diastolic flow velocity and carotid far‐wall circumferential strain (FWCS). Carotid FWCS is inversely related to vessel stiffness, where a decrease in FWCS indicates increased vessel stiffness. Right‐side FWCS did not differ between women with a history of PE versus normotensive pregnancy. Left carotid artery FWCS was lower in formerly preeclamptic women after adjustment for diameter, pulse pressure, and heart rate compared to women following an uncomplicated pregnancy (3.35 ± 1.08 × 10−3 vs. 4.46 ± 1.40 × 10−3; p = 0.003). Those with prior severe PE had the greatest decrease in FWCS adjusted to diameter, pulse pressure, and heart rate compared to healthy controls (p = 0.02). Adjusted FWCS and total serum cholesterol were independent indicators of PE history when present in a logistic regression model with confounding variables including age, body mass index, and resting blood pressure. Further investigation is needed to elucidate if FWCS can be used as a risk stratification tool for future cardiovascular disease following a pregnancy complicated by PE. A history of PE is associated with decreased left FWCS (increased left carotid artery stiffness).

Use of a Wearable Biosensor to Study Heart Rate Variability in Chronic Obstructive Pulmonary Disease and Its Relationship to Disease Severity

The purpose of this study was to explore the relationships between heart rate variability (HRV) and various phenotypic measures that relate to health and functional status in chronic obstructive pulmonary disease (COPD), and secondly, to demonstrate the feasibility of ascertaining HRV via a chest-worn wearable biosensor in COPD patients. HRV analysis was performed using SDNN (standard deviation of the mean of all normal R-R intervals), low frequency (LF), high frequency (HF), and LF/HF ratio. We evaluated the associations between HRV and COPD severity, class of bronchodilator therapy prescribed, and patient reported outcomes. Seventy-nine participants with COPD were enrolled. There were no differences in SDNN, HF, and LF/HF ratio according to COPD severity. The SDNN in participants treated with concurrent beta-agonists and muscarinic antagonists was lower than that in other participants after adjusting heart rate (beta coefficient −3.980, p = 0.019). The SDNN was positively correlated with Veterans Specific Activity Questionnaire (VSAQ) score (r = 0.308, p = 0.006) and handgrip strength (r = 0.285, p = 0.011), and negatively correlated with dyspnea by modified Medical Research Council (mMRC) questionnaire (r = −0.234, p = 0.039), health status by Saint George’s Respiratory Questionnaire (SGRQ) (r = −0.298, p = 0.008), symptoms by COPD Assessment Test (CAT) (r = −0.280, p = 0.012), and BODE index (r = −0.269, p = 0.020). When measured by a chest-worn wearable device, reduced HRV was observed in COPD participants receiving inhaled beta-sympathomimetic agonist and muscarinic antagonists. HRV was also correlated with various health status and performance measures.

A sudden change of heart: Warm acclimation can produce a rapid adjustment of maximum heart rate and cardiac thermal sensitivity in rainbow trout.

Warm acclimation in fish is often characterized by an increase in heat tolerance and a reduction in physiological rates to improve the scope to respond to additional challenges including further warming. The speed of these responses can determine their effectiveness. However, acclimation rates vary across levels of biological organization and are poorly understood in part because most research is conducted after an acclimation period of >3 weeks, when acclimation is presumed to be complete. Here we show that when rainbow trout were transferred from 10 to 18 °C, over 50% of the total reduction of maximum heart rate (ƒHmax) (i.e. the thermal compensation at moderate temperatures) occurred within 72 h, with further compensation occurring more gradually over the following 25 days. Also, the ability to increase ƒHmax with acute warming improved within 24 h resulting in a 30% rise in peak ƒHmax, but this ultimately declined again with prolonged (28 days) exposure to 18 °C. In contrast with some previous studies, upper critical temperatures for ƒHmax did not increase. Nonetheless, we demonstrate that rapid cardiac plasticity is possible in rainbow trout and likely blunts the impacts of thermal variation over relatively short timescales, such as that associated with heat waves and migration between water bodies.

Body Composition and Physical Fitness Affect Central Hemodynamics in Young Children.

Objective: Central hemodynamics are related to cardiovascular (CV) outcomes in adults, but associations with childhood CV risk remain unclear. The study aimed to investigate the association of obesity, physical activity, and fitness with parameters of central pulse wave reflection in young prepubertal children.Methods: In this cross-sectional study, 1,324 primary school children (aged 7.2 ± 0.4 years) were screened for parameters of pulse wave reflection such as augmentation index (AIx), central pulse pressure (CPP), body mass index (BMI), and cardiorespiratory fitness (CRF) by standardized procedures for children.Results: The mean AIx and AIx@75 were 22.2 ± 7.7 and 29.2 ± 9.2%, respectively. With each unit increase in BMI, AIx [−0.226 (−0.328; −0.125)%] and AIx@75 [−0.444(−0.660; −0.229)%] decreased, whereas peak forward pulse wave increased (p < 0.001). Increasing BMI was associated with higher CPP, but did not remain significant after adjustment for CRF and heart rate. One unit increase in CRF was associated with lower AIx@75 [−0.509(−0.844; −0.173)%, p = 0.003] and lower reflection magnitude [RM: −0.559 (−0.890; −0.227), p = 0.001], independent of body weight and height. Girls had significantly higher AIx, AIx@75, peak backward pulse wave, and RM compared with boys.Conclusion: Childhood obesity was associated with higher CPP but lower augmentation of the reflected pulse wave in children. Assessment of central blood pressures appears to be a valuable asset to childhood CV risk screening. The validity of augmentation indices during childhood development and the association with early vascular aging in children need to be verified in long-term follow-up studies. Physical activity and fitness have the potential to improve vascular hemodynamics in susceptible children and, thus, counteract vascular aging.Trial registry: ClinicalTrials.gov: Exercise and Arterial Modulation in Youth. Identifier: NCT02853747; URL: https://clinicaltrials.gov/ct2/show/NCT02853747.

INHALED NITRIC OXIDE VIA HIGH-FLOW NASAL CANNULA IN PATIENTS WITH ACUTE RESPIRATORY FAILURE RELATED TO COVID-19

INHALED NITRIC OXIDE VIA HIGH-FLOW NASAL CANNULA IN PATIENTS WITH ACUTE RESPIRATORY FAILURE RELATED TO COVID-19

Biatrial volume ratio predicts low voltage areas in atrial fibrillation.

BackgroundLeft atrial volume (LAV) and low voltage areas (LVAs) are acknowledged markers for worse rhythm outcome after ablation of atrial fibrillation (AF). Some studies reported the importance of increased right atrial volume (RAV) as a predictor for arrhythmia recurrences in AF patients.ObjectiveTo investigate association between the LAV/RAV ratio and LVAs presence.MethodsPatients undergoing first AF ablation were included. LVAs were assessed peri‐procedurally using high‐density 3D maps and defined as <0.5 mV. All patients underwent pre‐procedural cardiovascular magnetic resonance imaging. LAV (biplane) and RAV (monoplane 4‐chamber) were assessed prior to ablation, and the LAV/RAV ratio was calculated.ResultsThe study population included 189 patients (age mean 63 ± 10 years, 33% women, 57% persistent AF, 22% LVAs). There were 149 (79%) patients with LAV > RAV. In univariable analysis LAV > RAV was associated with LVAs (OR 6.803, 95%CI 1.395–26.514, p = .016). The association remained robust in multivariable model after adjustment for persistent AF, CHA2DS2‐VASc score, and heart rate (OR 5.981, 95%CI 1.256–28.484, p = .025). Using receiver operator curve analysis, LAV > RAV (AUC 0.668, 95%CI 0.585–0.751, p = .001) was significant predictor for LVAs. In multivariable analysis, after adjustment for age, persistent AF, and renal function, RAV≥LAV was threefold higher in males (OR 3.040, 95%CI 1.050–8.802, p = .04).ConclusionsLAV > RAV is useful for the prediction of electro‐anatomical substrate in AF. LAV > RAV was associated with LVAs presence, while male sex remained associated with RAV≥LAV and less LVAs.

Real World Pharmacological First Treatment Patterns of Patients With Parkinson Disease and Disease Duration: A Large-Scale Cohort Study Using an Health Maintenance Organization Database.

Real-world data were used to describe first antiparkinsonian drug (FAPD) prescription patterns among Parkinson disease (PD) patients and to evaluate disease duration until levodopa (l-DOPA) treatment and until death, as related to FAPD, by age group. The community-based cohort (2000-2012) included 6243 patients, members of an Israeli Health Maintenance Organizations. Time from FAPD purchase to 2 end points (l-DOPA purchase and death) was calculated. Cox regressions were used to estimate adjusted heart rate (HR) to either end point as related to FAPD type, by age group. During a mean follow-up of 4.8 ± 3.2 years, one third of the cohort died. The percent of l-DOPA use as a start drug increased with age, whereas the percent of dopamine agonists (DAs) and monoamine oxidase inhibitor B inhibitor (MAO-BI) decreased with age. Younger women were treated more often with DA as a start drug compared with younger men. In ages of younger than 50 years, time to l-DOPA start in the initial DA-group was 4 times longer than in the initial MAO-BI group (HR, 0.23; 95% confidence interval, 0.08-0.43; 1/0.23, 4.35). All age groups exhibited a similar survival time trend associated with initial drug type. An age-pooled HR with initial l-DOPA-group as a reference group yielded that survival time was 2.4 times longer for the initial DA group (HR, 0.41; 95% confidence interval, 0.31-0.55; 1/0.41, 2.44), 1.9 times and 1.4 times for initial MAO-BI or amantadine, respectively. First antiparkinsonian drug choice might be associated with time until l-DOPA initiation but may represent disease severity at the time of prescription, thus also affecting survival time as well. Real-world data illustrated that this choice is also age and sex dependent.

Sleep Apnea is Associated With Accelerated Vascular Aging: Results From 2 European Community-Based Cohort Studies.

BackgroundThe mechanisms underlying the association between obstructive sleep apnea (OSA) and cardiovascular disease may include accelerated vascular aging. The aim was to compare the magnitude of vascular aging in patients with high versus low risk of OSA.Methods and ResultsIn 2 community‐based studies, the PPS3 (Paris Prospective Study 3) and the Maastricht Study, high risk of OSA was determined with the Berlin questionnaire (a screening questionnaire for OSA). We assessed carotid artery properties (carotid intima‐media thickness, Young’s elastic modulus, carotid‐femoral pulse wave velocity, carotid pulse wave velocity, carotid diameter using high precision ultrasound echography), and carotid‐femoral pulse wave velocity (in the Maastricht Study only). Regression coefficients were estimated on pooled data using multivariate linear regression. A total of 8615 participants without prior cardiovascular disease were included (6840 from PPS3, 62% men, mean age 59.5±6.2 years, and 1775 from the Maastricht Study, 51% men, 58.9±8.1 years). Overall, high risk of OSA prevalence was 16.8% (n=1150) in PPS3 and 23.8% (n=423) in the Maastricht Study. A high risk of OSA was associated with greater carotid intima‐media thickness (β=0.21; 0.17–0.26), Young’s elastic modulus (β=0.21; 0.17–0.25), carotid‐femoral pulse wave velocity (β=0.24; 0.14–0.34), carotid pulse wave velocity (β=0.31; 0.26–0.35), and carotid diameter (β=0.43; 0.38–0.48), after adjustment for age, sex, total cholesterol, smoking, education level, diabetes mellitus, heart rate, and study site. Consistent associations were observed after additional adjustments for mean blood pressure, body mass index, or antihypertensive medications.ConclusionsThese data lend support for accelerated vascular aging in individuals with high risk of OSA. This may, at least in part, underlie the association between OSA and cardiovascular disease.

Association of Circulating Extracellular Matrix Components with Central Hemodynamics and Arterial Distensibility of Peripheral Arteries

Background: In addition to neuronal and endothelial regulators of vascular tone, the passive mechanical properties of arteries, determined by the molecular structure of extracellular matrices, are the principle modulators of vascular distensibility. Specifically, the association between collagen type IV (Col IV), a constituent of basement membrane, and arterial compliance remains unclear. Methods: In 31 healthy adult men, radial applanation tonometry and pulse wave analysis were used to assess aortic augmentation index (AIx), aortic-to-radial pulse pressure amplification (PPAmpl), and time to reflection wave. Results: Plasma Col IV and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) concentrations were correlated with AIx (r = 0.51, p = 0.021 and r = −0.45, p = 0.042, respectively) after adjustment for age and heart rate (HR). Greater matrix metalloproteinase-9 (MMP-9) and TIMP-1 levels were associated with high PPAmpl (r = 0.45 and r = 0.64, respectively) and hence with compliant arteries. Multiple regression analyses revealed that 99% of the variation in PPAmpl was attributable to age, HR, Col IV, TIMP-1, and Col × TIMP-1 interaction (p < 0.001). No relations between tonometric variables and levels of MMP-1, -2, and -3; TIMP-2 and -4; fibronectin; glycosaminoglycans; and hydroxyproline were found. Conclusion: High circulating Col IV level indexes were associated with stiffer peripheral arteries whereas increased MMP-9 and TIMP-1 concentrations were associated with more compliant ones.

Degree of arterial stiffness is comparable across inflammatory joint disease entities

Objectives: Inflammatory joint disease (IJD) is associated with an increased risk of developing cardiovascular disease (CVD). Arterial stiffness is both a risk factor and a surrogate marker for CVD. This study aims to compare arterial stiffness across patients with rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis, and, by extension, to explore the relationship between arterial stiffness and the estimated CVD risk by the Systematic COronary Risk Evaluation (SCORE) algorithm. Method: During the study period, from April 2017 to June 2018, 196 patients with IJD visited the Preventive Cardio-Rheuma Clinic in Oslo, Norway. A CVD risk stratification was performed, including the assessment of traditional risk factors and the measurement of arterial stiffness. Results: Thirty-six patients (18.4%) had elevated aortic pulse wave velocity (aPWV) (≥ 10 m/s). After adjustment for age and heart rate, arterial stiffness was comparable across the IJD entities (p = 0.69). Associated factors, revealed by regression analysis, were age, blood pressure, heart rate, presence of carotid plaques, established CVD, non-steroidal anti-inflammatory drugs, and statin use. Furthermore, aPWV was positively correlated with estimated CVD risk (r = 0.7, p < 0.001) and patients with a very high predicted CVD risk (SCORE ≥ 10%) had significantly higher aPWV than patients at lower CVD risk (9.2 vs 7.5 m/s, p < 0.001). Conclusion: The degree of arterial stiffness was comparable across the IJD entities and was highly associated with the estimated CVD risk. Our findings support the need for an increased focus on prevention of CVD in all patients with IJD.

Premorbid \u03b21-selective (but not non-selective) \u03b2-blocker exposure reduces intensive care unit mortality among septic patients

Backgroundβ-blockers may protect against catecholaminergic myocardial injury in critically ill patients. Long-term β-blocker users are known to have lower lactate concentrations and favorable sepsis outcomes. However, the effects of β1-selective and nonselective β-blockers on sepsis outcomes have not been compared. This study was conducted to investigate the impacts of different β-blocker classes on the mortality rate in septic patients.MethodsWe retrospectively screened 2678 patients admitted to the medical or surgical intensive care unit (ICU) between December 2015 and July 2017. Data from patients who met the Sepsis-3 criteria at ICU admission were included in the analysis. Premorbid β-blocker exposure was defined as the prescription of any β-blocker for at least 1 month. Bisoprolol, metoprolol, and atenolol were classified as β1-selective β-blockers, and others were classified as nonselective β-blockers. All patients were followed for 28 days or until death.ResultsAmong 1262 septic patients, 209 (16.6%) patients were long-term β-blocker users. Patients with premorbid β-blocker exposure had lower heart rates, initial lactate concentrations, and ICU mortality. After adjustment for disease severity, comorbidities, blood pressure, heart rate, and laboratory data, reduced ICU mortality was associated with premorbid β1-selective [adjusted hazard ratio, 0.40; 95% confidence interval (CI), 0.18–0.92; P = 0.030], but not non-selective β-blocker use.ConclusionPremorbid β1-selective, but not non-selective, β-blocker use was associated with improved mortality in septic patients. This finding supports the protective effect of β1-selective β-blockers in septic patients. Prospective studies are needed to confirm it.

Cardiac Morphology, Function, and Hemodynamics in Patients With Morbid Obesity and Nonalcoholic Steatohepatitis.

BackgroundThe patients with nonalcoholic fatty liver disease demonstrate an increased cardiovascular risk. The adverse influence of liver abnormalities on cardiac function are among many postulated mechanisms behind this association. The aim of the study was to evaluate cardiac morphology and function in patients with morbid obesity referred for bariatric surgery with liver biopsy.Methods and ResultsWe evaluated with echocardiography 171 consecutive patients without known cardiac disease (median age 42 [interquartile range, 37–48] years, median body mass index 43.7 [interquartile range, 41.0–47.5], 67% female patients. Based on the liver biopsy results, there were 44 patients with nonalcoholic steatohepatitis (NASH), 69 patients with isolated steatosis, and 58 patients without steatosis. Patients with NASH demonstrated signs of left ventricular concentric remodeling and hyperdynamic circulation, including indexed left ventricular end‐diastolic diameter [cm/m2]: NASH 1.87 [0.22]; isolated steatosis 2.03 [0.33]; without steatosis 2.01 [0.19], P=0.001; relative wall thickness: NASH 0.49±0.05, isolated steatosis 0.47±0.06, without steatosis 0.46±0.06, P=0.011; cardiac index [L/m2]: NASH 3.05±0.54, isolated steatosis 2.80±0.44, without steatosis 2.79±0.50, P=0.013. After adjustment for sex, age, blood pressure, and heart rate, most of the measures of the left ventricular systolic and diastolic function, left atrial size, right ventricular function, and right ventricular size did not differ between groups.ConclusionsIn a group of patients with extreme obesity, NASH was associated with left ventricular concentric remodeling and hyperdynamic circulation. Increased cardiac output in NASH may represent an additional risk factor for incident cardiovascular events in this population.

Effects of high-intensity interval training in patients with coronary artery disease after percutaneous coronary intervention: A systematic review and meta-analysis.

AimTo evaluate whether high‐intensity interval training (HIIT) was superior to low‐intensity training or usual care among patients after percutaneous coronary intervention. The hypothesis was that HIIT would help patients after percutaneous coronary intervention (PCI) improve cardiopulmonary function, lipid profiles and in‐stent restenosis.DesignA systematic review and meta‐analysis were conducted according to the Preferred Reporting Items for Systematic Review and Meta‐analysis (PRISMA)2009 Checklist.MethodsRandomized controlled trials (RCTs) focusing on HIIT programme in patients after PCI were searched in Cochrane Library, Web of Science Core Collection, EMbase, PubMed, China National Knowledge Infrastructure (CNKI) and SinoMed from the inception to 24 March 2020. Standard Mean difference (SMD) and 95% confidence intervals (CI) were performed to summarize the effect sizes.ResultsSix RCTs (247 patients) met the criteria. HIIT programme had a statistically significant effect on raising left ventricular ejection function (LVEF) (SMD = 0.38, 95%CI [0.03, 0.73], I 2 = 3%), VO2peak (SMD = 0.94, 95%CI [0.61, 1.28], I 2 = 0%), as well as improving the serum level of high‐density lipoprotein (SMD = 0.55, 95%CI [0.06, 1.03], I 2 = 0%) and late luminal loss (SMD = −0.65, 95%CI [−1.07, −0.23], I 2 = 0%). But HIIT had no prominent effect on improving heart rate (SMD = −0.04, 95%CI [−0.29, 0.21], I 2 = 0%). Summarily, HIIT programme appears to be favourable for CAD patients after PCI by improving cardiopulmonary function, such as LVEF and VO2peak, as well as reducing late luminal loss in per stented arteries. Nevertheless, HIIT has no advantage for adjusting heart rate. More researches with rigorous methods are warranted to explore the controversy about lipid profiles.

Circadian variation of the QT interval and heart rate variability and their interrelationship

BackgroundWhether the QT interval displays circadian rhythm after heart rate correction is unresolved and the relationship of QT interval to heart rate variability (HRV) is uncertain. ObjectivesTo test the hypothesis that there is a circadian rhythm to QT interval and HRV and determine the relationship between QTc and HRV. MethodsThe hourly average ECG data from 24-h ECGs were examined in individuals (50 without medications and 9 on beta blockers only) with no evidence of coronary artery disease or structural heart disease. The QT duration of normal QRS complexes from a series of 30-s windows was measured. The presence of circadian rhythm was tested by the data analytic approach of goodness of fit to a cosine function. ResultsQT interval with and without heart rate correction showed a circadian rhythm for five heart rate adjustment formulae except for the Bazett formula. HRV also showed circadian rhythm but with different acrophages and nadirs depending on the HRV component. There were significant (p < 0.05) positive correlations of QTc with pNN50 rms-SD and SDNN and significant (p < 0.05) negative correlations with SDANN and Tri. The beta blocker group did not generally show circadian rhythm for QT interval or HRV. ConclusionQT, after heart rate adjustment, and HRV have circadian rhythmicity. There are significant correlations between QT interval and HRV indices. Circadian rhythm was blunted with beta blockers. The data are consistent with the concept of a predominance of parasympathetic activity to increase QTc and sympathetic activity to shorten QTc, even after ‘correction’ of the QT interval for heart rate.

Impaired pulse pressure amplification, augmentation index, and arterial stiffness are associated with reduced limb lean mass in overweight and obese postmenopausal women.

The age-related muscle mass loss has been associated with increased arterial stiffness (brachial-ankle pulse wave velocity, baPWV) and wave reflection (augmentation index, AIx). In healthy individuals, pulse pressure (PP) is lower in the aorta compared to the brachial artery (PP amplification, PPA). Postmenopausal women experience elevated aortic stiffness leading to increased AIx and aortic PP causing reduced PPA, an independent predictor of cardiovascular mortality. It is unknown whether appendicular skeletal muscle index (ASMI), arm (ArmLM) or leg lean mass (LegLM) are negatively associated with PPA. The purpose of this study was to investigate the associations between vascular function (PPA, AIx, and baPWV) and lean mass (ASMI, ArmLM, and LegLM) in postmenopausal women. The study was performed in 93 postmenopausal women (48-71years; BMI: 30±7kg/m2). PPA (brachial/aortic PP), aortic AIx, and baPWV were measured. ArmLM and LegLM were measured by dual-energy X-ray absorptiometry. ASMI was calculated as (ArmLM+LegLM)/Ht2. Associations between vascular and lean mass measures were analyzed by multiple linear regression. PPA was associated with ASMI (β=0.29, p=.016) and LegLM (β=0.25, p=.028) after adjustment for age, height, systolic pressure, strength, and heart rate. AIx was associated with ASMI (β=-0.27, p=.011), ArmLM (β=-0.25, p=.023), and LegLM (β=-0.22, p=.026), while baPWV was associated with reduced ASMI (β=-0.23, p=.043) and ArmLM (β=-0.23, p=.045), but not with LegLM (β=-0.19, p=.074) after full adjustment. Our findings indicate that impaired pulsatile hemodynamics (PPA and AIx) are negatively associated with ASMI and LegLM, while arterial stiffness is negatively associated with ASMI and ArmLM. Thus, vascular dysfunction may be implicated in muscle mass loss in overweight and obese postmenopausal women.

Abstract 16829: Isolated Left Atrial, Biatrial or Right Atrial Dilatation - Association With Low Voltage Areas in Patients With Atrial Fibrillation

Background: Left atrial volume (LAV) and low voltage areas (LVA) are markers for impaired outcome after ablation of atrial fibrillation (AF). Some studies reported the importance of increased right atrial volume (RAV) as a predictor for arrhythmia recurrences in AF patients. Hypothesis: to investigate association between the LAV/RAV ratio and LVA presence. Methods: Patients undergoing first AF ablation with pre-procedural cardiovascular magnetic resonance (CMR) imaging were included. LVA were assessed peri-procedurally using high-density 3D maps and defined as &lt;0.5 mV. LAV was determined using a biplane model based on cine 4- and 2-chamber views, RAV using a monoplane model based on the cine 4-chamber view. Both volumes were indexed to body surface areas, and the LAV/RAV ratio was calculated. LAV/RAV ratio &gt;1 indicated isolated LA dilatation, ratio ≤1 was defined as biatrial/isolated RA dilatation. Results: The study population included 184 patients (Age 63±10 years, 34% women, 58% persistent AF, 22% LVA). There were 148 (80%) patients with isolated LA dilatation. In univariable analysis, isolated LA dilatation was associated with LVAs (OR 6.803, 95% CI 1.395-26.514, p=0.016). This association remained robust in multivariable model after adjustment for persistent AF, CHA 2 DS 2 -VASc score, renal function, and heart rate (OR 5.981, 95%CI 1.256-28.484, p=0.025). Using ROC analysis, LAV/RAV ratio (AUC 0.668, 95% CI 0.585-0.751, p&lt;0.001, Figure) was significant predictor for LVA. Biatrial/isolated RA dilatation occurred in 36 (20%) patients. On multivariable analysis, after adjustment for age, persistent AF, and renal function, male sex remained significantly associated with biatrial/isolated RA dilatation (OR 3.040, 95% CI 1.050-8.802, p=0.040). Conclusions: LAV/RAV ratio is useful for the prediction of LVA in AF. Isolated LA dilatation was associated with LVA presence, while male sex remained associated with biatrial/isolated RA dilatation and less LVA.

The influence of diabetes and prediabetes on left heart remodeling: A population-based study.

Diabetes was regarded as an independent risk factor for abnormal left heart remodeling. However, there was lacking population-based data on the relationship of glucose status with left ventricular hypertrophy (LVH) or left atrial enlargement (LAE). This study intended to clarify the influence of diabetes and prediabetes on the prevalence and incidence of LVH and LAE based on a northeast rural population of China. We analyzed clinical, laboratory and echocardiographic data of a total of 2824 participants aged over 35 years from a population-based prospective cohort NCRCHS study with 2 years of follow-up, which was carried out in rural areas of northeast China. All measurements were performed according to standardized protocols. There were 2179 controls, 342 subjects with prediabetes and 303 ones with diabetes. The baseline distribution of LAD, IVSd, LVIDd, LVIDs, LVMI, E wave, A wave, E/A, E/e', diastolic dysfunction, LVEDV, LVESV and SV was significantly different among three groups (all Ptrend<0.05). After the adjustment for age, gender, BMI, waist circumference, heart rate, hypertension and dyslipidemia, glucose status remained associated with LVIDd and E/e' (all P < 0.05). At baseline, diabetes was independently related to the prevalence of LVH (OR = 1.53; 95%CI = 1.12-2.10; P < 0.01) and LAE (OR = 1.71; 95%CI = 1.19-2.43; P < 0.01) in the overall population, and the same significant results were also found in gender specific subgroups. During the 2-year follow-up, Cox regression models revealed that baseline diabetes had an independent association with the incidence of LAE in the total subjects (HR = 1.83; 95%CI = 1.10-3.06; P = 0.02) and females (HR = 1.90; 95%CI = 1.05-3.46; P = 0.04) after adjusting the potential confounders. Diabetes, but not prediabetes, is an independent predictor for the prevalence of LVH and LAE, and for the new-onset LAE, it should be considered in the assessment of diabetes and cardiac structural remodeling.

Outcomes of Pulmonary Vein Isolation in Athletes

The aims of this study were to assess outcomes of pulmonary vein isolation (PVI) performed on athletes at a tertiary care center and to characterize its efficacy and physiological effects. The incidence of atrial fibrillation (AF) is increased in highly trained athletes and poses unique management challenges. Athletes were identified through a database of patients undergoing PVI from January 2000 through October 2015. Outcomes of AF ablation were defined in accordance with published guidelines. Available electrocardiographic, echocardiographic, and exercise treadmill testing data were also analyzed. The study population included 144 athletes (93% men; mean age 50.4 ± 8.6 years; 97 paroxysmal, 38persistent, and 9 long-standing persistent) with median follow-up of 3 years. Single-procedure freedom from arrhythmia was 75%, 68%, and 33% at 1 year for paroxysmal, persistent, and long-standing persistent AF, respectively. Multiple-procedure freedom from arrhythmia off antiarrhythmic drugs was 86%, 76%, and 56% in respective groups at the end of follow-up (mean 1.4 ± 0.7 ablations per athlete). Compared with a matched cohort of nonathletes who underwent PVI, there was no difference in arrhythmia recurrence (log-rank p=0.23). Excluding long-standing persistent AF, longer diagnosis-to-ablation time was the only variable in Cox proportional hazards analyses associated with arrhythmia recurrence (adjusted heart rate per log increase: 1.92; 95% confidence interval: 1.40 to 2.73; p<0.0001), and PVI within 2 years of diagnosis was notably associated with successful outcomes (log-rank p=0.002). Sinus rate increased following the index ablation (mean 54 beats/min vs. 64 beats/min at >1 year; p<0.0001), but maximum metabolic equivalents on exercise treadmill testing were unchanged (13.1 ± 1.2 vs. 12.7 ± 1.4; p=0.44). PVI is an effective therapy in athletes with paroxysmal and persistent AF, and arrhythmia recurrence was no different from that among matched nonathletes. Early ablation was associated with improved success rates. Sustained cardioautonomic effects were observed following ablation, but exercise capacity was preserved.