Does obesity affect the non-invasive measurement of cardiac output performed by electrical cardiometry in children and adolescents?

Electrical cardiometry (EC) is a non-invasive and inexpensive method for hemodynamic assessment and monitoring. However, its feasibility for widespread clinical use, especially for the obese population, has yet to be determined. In this study, we evaluated the agreement and reliability of EC compared to transthoracic Doppler echocardiography (TTE) in normal, overweight, and obese children and adolescents. We measured stroke volume (SV) and cardiac output (CO) of 131 participants using EC and TTE simultaneously. We further divided these participants according to BMI percentiles for subanalyses: <85% normal weight (n = 41), between 85 and 95% overweight (n = 7), and >95% obese (n = 83). Due to small sample size of the overweight group, we combined overweight and obese groups (OW+OB) with no significant change in results (SV and CO) before and after combining groups. There were strong correlations between EC and TTE measurements of SV (r = 0.869 and r = 0.846; p < 0.0001) and CO (r = 0.831 and r = 0.815; p < 0.0001) in normal and OW+OB groups, respectively. Bias and percentage error for CO measurements were 0.240 and 29.7%, and 0.042 and 29.5% in the normal and OW+OB groups, respectively. Indexed values for SV were lower in the OW+OB group than in the normal weight group when measured by EC (p < 0.0001) but no differences were seen when measured by TTE (p = 0.096). In all weight groups, there were strong correlations and good agreement between EC and TTE. However, EC may underestimate hemodynamic measurements in obese participants due to fat tissue.

Implementation of clinical research trials using web-based and mobile devices: challenges and solutions.

BACKGROUND: With the increasing implementation of web-based, mobile health interventions in clinical trials, it is crucial for researchers to address the security and privacy concerns of patient information according to high ethical standards. The full process of meeting these standards is often made more complicated due to the use of internet-based technology and smartphones for treatment, telecommunication, and data collection; however, this process is not well-documented in the literature. RESULTS: The Smart Heart Trial is a single-arm feasibility study that is currently assessing the effects of a web-based, mobile lifestyle intervention for overweight and obese children and youth with congenital heart disease in Southwestern Ontario. Participants receive telephone counseling regarding nutrition and fitness; and complete goal-setting activities on a web-based application. This paper provides a detailed overview of the challenges the study faced in meeting the high standards of our Research Ethics Board, specifically regarding patient privacy. CONCLUSION: We outline our solutions, successes, limitations, and lessons learned to inform future similar studies; and model much needed transparency in ensuring high quality security and protection of patient privacy when using web-based and mobile devices for telecommunication and data collection in clinical research.

Outcomes in PIC-Related CNV: Pooled Analysis of Individual Participant Data.

Choroidal neovascularization (CNV) affects 64-75% of eyes with punctate inner choroidopathy (PIC). Although anti-VEGF agents are considered first-line therapy, there is controversy regarding other modalities, such as immunosuppression. We performed a systematic review of individual participant data (IPD) and generated a dataset of 278 eyes with PIC-related CNV from 45 studies. Forty-two percent presented with moderate visual loss (MVL) or worse. Four different treatment modalities (anti-VEGF, photodynamic therapy, local immunosuppression, and systemic immunosuppression) and most combinations among them were represented. Anti-VEGF injections decreased the likelihood of MVL (Odds Ratio 0.3, p = .027), an effect moderated by presenting visual acuity and patient age. Eyes receiving more than 3 injections were more likely to receive additional therapeutic modalities. Increasing number of modalities was associated with longer follow-up time and did not improve vision. The beneficial effect of anti-VEGF injections persisted when controlling for presenting visual acuity and follow-up time.

Ophthalmic findings in marginally housed women in a Canadian city.

OBJECTIVE: To assess the prevalence and common causes of ocular pathology experienced by vulnerable women with marginalized housing and/or a history of abuse, violence, and trafficking. METHODS: Using a stratified random sampling technique, we recruited 93 women living in 10 randomly selected women's shelters in Toronto, Canada between May and November of 2018. All English-speaking females older than the age of 18 were eligible to participate. Data on demographics, medical or ocular history, subjective visual acuity, and access to eye care were obtained. Comprehensive visual screening and dilated fundoscopy were performed for each participant. RESULTS: The median age was 40 years (interquartile range, 30.5-54 years) and the median duration of homelessness was 8 months (interquartile range, 2.25-20.5 months); 63.4% of participants reported a history of abuse, 44.9% experienced head trauma, 15.9% experienced eye trauma, 22.5% identified as refugees, and 2.17% (2 of 92) had been victims of human trafficking. The above variables were not significantly related to vision problem severity on univariate analysis. Based on the presenting visual acuity, 27.8% of participants (95% CI [18.9-38.2]) were found to have visual impairment. Visual impairment was mainly related to refractive error (54.8% [51 of 93]), however, nonrefractive pathology was also observed. Of all the participants, 64.5% had one or more abnormal findings during the vision screening, and 40.9% needed follow-up by an ophthalmologist. Most participants (96.7%) expressed interest in accessing free eye examinations. CONCLUSIONS: Visual impairment is highly prevalent among homeless women living in Toronto. Routine vision-screening programs present an opportunity to improve the ocular health of this vulnerable population.

Identifying gaps in patient access to diabetic screening eye examinations in Ontario: a provincially representative cross-sectional study.

OBJECTIVE: Diabetes is the leading cause of acquired blindness in Canadians under the age of 50 years, and diabetic retinopathy affects an estimated 500 000 Canadians. Early identification of retinopathy with screening eye examinations allows for secondary prevention. To understand the need for resource allotment in diabetic screening, we undertook a cross-sectional study of key demographics and geographics of screened and unscreened patients in Ontario. METHODS: Ontario Health Insurance Plan (OHIP) records were derived from physician and optometry billing, matched with patients aged >19 years with prevalent diabetes between 2011 and 2013. Data were cross-correlated with demographic covariates, including age, sex, income quintile, immigrant status, as well as geographic covariates such as rurality and patient Local Health Integration Network (LHIN). RESULTS: Of almost 1 146 000 patients included in the analysis, approximately 406 000 were unscreened. Of note, this included 234 000 adults aged 40-64 years. Approximately 818 000 patients with diabetes lived in large cities, and 301 000 (37%) were unscreened. When the City of Toronto was analyzed as an urban area with the highest density of unscreened prevalence, autocorrelation between the percentage of eye examinations among patients with diabetes aged >40 years and low-income revealed that large areas of Toronto Central correlated for low examination rates and low income. The majority (13/22) of Community Health Centres are present in these areas. CONCLUSIONS: Large cross-sectional population statistics for diabetes prevalence and ophthalmic examinations provides a geographic and socioeconomic profile for populations of middle-aged adults in large urban areas at risk for developing diabetic retinopathy and who might benefit from interventions to improve the rates of screening eye examinations.

Increased blood pressure is associated with increased carotid artery intima-media thickness in children with repaired coarctation of the aorta.

OBJECTIVES: The intima-media thickness of the common carotid artery (cIMT) is a good noninvasive surrogate marker for cardiovascular disease. Regular cIMT monitoring in children with congenital heart disease has great potential. We sought to determine which anthropomorphic and haemodynamic variables were significantly associated with the cIMT in paediatric patients with obesity and children with repaired coarctation of the aorta (CoA). METHODS: We measured the cIMT in 143 children aged 5 to less than 18 years including normal weight controls (n = 44), children with overweight/obesity (n = 73) and children with repaired CoA (n = 26). cIMT was compared and the association between the cIMT and patient characteristics, including obesity and blood pressure (BP), was investigated. RESULTS: BMI z score, sex and the presence of CoA were significant independent predictors of cIMT. The cIMT was significantly greater in children with overweight/obesity (0.53 ±â€Š0.06 mm) relative to normal weight controls (0.51 ±â€Š0.04 mm), as well as in CoA patients with abnormally high BP (0.57 ±â€Š0.08 mm) versus CoA patients with normal BP (0.52 ±â€Š0.05 mm) and controls (0.51 ±â€Š0.04 mm). CoA patients with normal BP did not have significantly increased cIMT. CONCLUSION: cIMT was positively associated with BMI z score, male sex and CoA repair in children. The increased cIMT in children with repaired CoA was because of those with abnormally high BP, which was masked in clinic for most of these patients. These findings warrant further investigations into the cIMT and other atherosclerotic risk factors to determine their potential clinical impact in these highly susceptible patients.

Non-invasive measurement of cardiac output in children with repaired coarctation of the aorta using electrical cardiometry compared to transthoracic Doppler echocardiography.

OBJECTIVE: To evaluate the equivalence of the ICON® electrical cardiometry (EC) haemodynamic monitor to measure cardiac output (CO) relative to transthoracic Doppler echocardiography (TTE) in paediatric patients with repaired coarctation of the aorta (CoA). APPROACH: A group of n = 28 CoA patients and n = 27 matched controls were enrolled. EC and TTE were performed synchronously on each participant and CO measurements compared using linear regression and Bland-Altman analysis. The CoA group was further subdivided into two groups, with n = 10 and without n = 18 increased left ventricular outflow tract velocity (iLVOTv) for comparison. MAIN RESULTS: CO measurements from EC and TTE in controls showed a strong correlation (R = 0.80, p < 0.001) and an acceptable percentage error (PE) of 28.1%. However, combining CoA and control groups revealed a moderate correlation (R = 0.57, p < 0.001) and a poor PE (44.2%). We suspected that the CO in a subset of CoA participants with iLVOTv was overestimated by TTE. Excluding the iLVOTv CoA participants improved the correlation (R = 0.77, p < 0.001) and resulted in an acceptable PE of 31.2%. SIGNIFICANCE: CO measurements in paediatric CoA patients in the absence of iLVOTv are clinically equivalent between EC and TTE. The presence of iLVOTv may impact the accuracy of CO measurement by TTE, but not EC.