Measurement and data transmission validity of a multi-biosensor system for real-time remote exercise monitoring among cardiac patients

Background: Remote telemonitoring holds great potential to augment management of patients with coronary heart disease (CHD) and atrial fibrillation (AF) by enabling regular physiological monitoring during physical activity. Remote physiological monitoring may improve home and community exercise-based cardiac rehabilitation (exCR) programs and could improve assessment of the impact and management of pharmacological interventions for heart rate control in individuals with AF.Objective: Our aim was to evaluate the measurement validity and data transmission reliability of a remote telemonitoring system comprising a wireless multi-parameter physiological sensor, custom mobile app, and middleware platform, among individuals in sinus rhythm and AF.Methods: Participants in sinus rhythm and with AF undertook simulated daily activities, low, moderate, and/or high intensity exercise. Remote monitoring system heart rate and respiratory rate were compared to reference measures (12-lead ECG and indirect calorimeter). Wireless data transmission loss was calculated between the sensor, mobile app, and remote Internet server.Results: Median heart rate (-0.30 to 1.10 b∙min-1) and respiratory rate (-1.25 to 0.39 br∙min-1) measurement biases were small, yet statistically significant (all P≤.003) due to the large number of observations. Measurement reliability was generally excellent (rho=.87-.97, all P<.001; intraclass correlation coefficient [ICC]=.94-.98, all P<.001; coefficient of variation [CV]=2.24-7.94%), although respiratory rate measurement reliability was poor among AF participants (rho=.43, P<.001; ICC=.55, P<.001; CV=16.61%). Data loss was minimal (<5%) when all system components were active; however, instability of the network hosting the remote data capture server resulted in data loss at the remote Internet server during some trials.Conclusions: System validity was sufficient for remote monitoring of heart and respiratory rates across a range of exercise intensities. Remote exercise monitoring has potential to augment current exCR and heart rate control management approaches by enabling the provision of individually tailored care to individuals outside traditional clinical environments

Screening for left ventricular hypertrophy in patients with type 2 diabetes mellitus in the community

<p>Abstract</p> <p>Background</p> <p>Left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular disease and is common among patients with type 2 diabetes. However, no systematic screening for LVH is currently recommended for patients with type 2 diabetes. The purpose of this study was to determine whether NT-proBNP was superior to 12-lead electrocardiography (ECG) for detection of LVH in patients with type 2 diabetes.</p> <p>Methods</p> <p>Prospective cross-sectional study comparing diagnostic accuracy of ECG and NT-proBNP for the detection of LVH among patients with type 2 diabetes. Inclusion criteria included having been diagnosed for > 5 years and/or on treatment for type 2 diabetes; patients with Stage 3/4 chronic kidney disease and known cardiovascular disease were excluded. ECG LVH was defined as either the Sokolow-Lyon or Cornell voltage criteria. NT-proBNP level was measured using the Roche Diagnostics Elecsys assay. Left ventricular mass was assessed from echocardiography. Receiver operating characteristic curve analysis was carried out and area under the curve (AUC) was calculated.</p> <p>Results</p> <p>294 patients with type 2 diabetes were recruited, mean age 58 (SD 11) years, BP 134/81 ± 18/11 mmHg, HbA_1c7.3 ± 1.5%. LVH was present in 164 patients (56%). In a logistic regression model age, gender, BMI and a history of hypertension were important determinants of LVH (p < 0.05). Only 5 patients with LVH were detected by either ECG voltage criteria. The AUC for NT-proBNP in detecting LVH was 0.68.</p> <p>Conclusions</p> <p>LVH was highly prevalent in asymptomatic patients with type 2 diabetes. ECG was an inadequate test to identify LVH and while NT-proBNP was superior to ECG it remained unsuitable for detecting LVH. Thus, there remains a need for a screening tool to detect LVH in primary care patients with type 2 diabetes to enhance risk stratification and management.</p

Prediction of preeclampsia and delivery of small for gestational age babies based on a combination of clinical risk factors in high-risk women

Objective. To develop clinical risk tools for preeclampsia and small for gestational age (SGA) in high-risk women. Methods. Individual risk scores based on clinical risk factors were calculated using logistic regression and validated in 1687 women with obesity in first pregnancy, chronic hypertension, or previous preeclampsia. Results. The risk of preeclampsia varied from 7% in obese primiparae without hypertension to 30% when previous preeclampsia and chronic hypertension occurred together. A prediction model incorporating these risk factors had a sensitivity of 48 and 89% for preeclampsia delivered <34 weeks' gestation. Conclusion. Multiple clinical risk factors increase the risk of preeclampsia and SGA.Paul T. Seed, Lucy C. Chappell, Michael A. Black, Katrina K. Poppe, Yuan-Chun Hwang, Nikola Kasabov, Lesley McCowan, Andrew H. Shennan, Steven H. Wu, Lucilla Poston, and Robyn A. Nort

The prognostic impact of diastolic dysfunction in patients with chronic heart failure and post-acute myocardial infarction: Can age-stratified E/A ratio alone predict survival?

To determine the prognostic implications of diastolic filling grades and identify whether age-stratified E/A ratio alone can identify patients at high risk of death post-AMI and HF. We hypothesized that in response to ageing and pathology, a normal E/A (>1) could be considered abnormal in patients post-AMI older than 65years, and that in patients with symptomatic HF, a normal E/A always represents advanced diastolic dysfunction

Genetic markers of repolarization and arrhythmic events after acute coronary syndromes

American Heart Journal1694579-58600

Predicting survival in heart failure: a risk score based on 39 372 patients from 30 studies.

AIMS: Using a large international database from multiple cohort studies, the aim is to create a generalizable easily used risk score for mortality in patients with heart failure (HF). METHODS AND RESULTS: The MAGGIC meta-analysis includes individual data on 39 372 patients with HF, both reduced and preserved left-ventricular ejection fraction (EF), from 30 cohort studies, six of which were clinical trials. 40.2% of patients died during a median follow-up of 2.5 years. Using multivariable piecewise Poisson regression methods with stepwise variable selection, a final model included 13 highly significant independent predictors of mortality in the following order of predictive strength: age, lower EF, NYHA class, serum creatinine, diabetes, not prescribed beta-blocker, lower systolic BP, lower body mass, time since diagnosis, current smoker, chronic obstructive pulmonary disease, male gender, and not prescribed ACE-inhibitor or angiotensin-receptor blockers. In preserved EF, age was more predictive and systolic BP was less predictive of mortality than in reduced EF. Conversion into an easy-to-use integer risk score identified a very marked gradient in risk, with 3-year mortality rates of 10 and 70% in the bottom quintile and top decile of risk, respectively. CONCLUSION: In patients with HF of both reduced and preserved EF, the influences of readily available predictors of mortality can be quantified in an integer score accessible by an easy-to-use website www.heartfailurerisk.org. The score has the potential for widespread implementation in a clinical setting

Is heart rate a risk marker in patients with chronic heart failure and concomitant atrial fibrillation? Results from the MAGGIC meta-analysis

Aim: To investigate the relationship between heart rate and survival in patients with heart failure (HF) and coexisting atrial fibrillation (AF). Methods and Results: Patients with AF included in the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) meta-analysis were the main focus of this analysis (3259 patients from 17 studies). The outcome was all-cause mortality at 3 years. Heart rate was analysed as a categorical (tertiles; T1 ≤77 b.p.m., T2 78–98 b.p.m., T3 ≥98 b.p.m.) and continuous variable. Cox proportional hazard models were used to compare the risk of all-cause death between tertiles of baseline heart rate. Patients in the highest tertile were more often female, less likely to have an ischaemic aetiology or diabetes, had a lower ejection fraction but higher blood pressure and New York Heart Association (NYHA) class. Higher heart rate was associated with higher mortality in patients with sinus rhythm (SR) but not in those in AF. In patients with heart failure and reduced ejection fraction (HF-REF) and AF, death rates per 100 patient years were lowest in the highest heart rate tertile (T1 18.9 vs. T3 15.9) but this difference was not statistically significant (P = 0.10). In patients with heart failure and preserved ejection fraction (HF-PEF), death rates per 100 patient years were highest in the highest heart rate tertile (T1 14.6 vs. T3 16.0, P = 0.014). However, after adjustment for other important prognostic variables, higher heart rate was no longer associated with higher mortality in HF-PEF (or HF-REF). Conclusions: In this meta-analysis of patients with HF, heart rate does not have the same prognostic significance in patients in AF as it does in those in SR, irrespective of ejection fraction or treatment with beta-blocker