A crowdsourced global data set for validating built-up surface layers.

Several global high-resolution built-up surface products have emerged over the last five years, taking full advantage of open sources of satellite data such as Landsat and Sentinel. However, these data sets require validation that is independent of the producers of these products. To fill this gap, we designed a validation sample set of 50 K locations using a stratified sampling approach independent of any existing global built-up surface products. We launched a crowdsourcing campaign using Geo-Wiki ( https://www.geo-wiki.org/ ) to visually interpret this sample set for built-up surfaces using very high-resolution satellite images as a source of reference data for labelling the samples, with a minimum of five validations per sample location. Data were collected for 10 m sub-pixels in an 80 × 80 m grid to allow for geo-registration errors as well as the application of different validation modes including exact pixel matching to majority or percentage agreement. The data set presented in this paper is suitable for the validation and inter-comparison of multiple products of built-up areas.

Clinical Benefits of Stem Cells for Chronic Symptomatic Systolic Heart Failure: A Systematic Review of the Existing Data and Ongoing Trials.

The benefits of stem cell therapy for patients with chronic symptomatic systolic heart failure due to ischemic and nonischemic cardiomyopathy (ICM and NICM, respectively) are unclear. We performed a systematic review of major published and ongoing trials of stem cell therapy for systolic heart failure and compared measured clinical outcomes for both types of cardiomyopathy. The majority of the 29 published studies demonstrated clinical benefits of autologous bone marrow-derived mesenchymal stem cells (BM-MSCs). Left ventricular ejection fraction (LVEF) was improved in the majority of trials after therapy. Cell delivery combined with coronary artery bypass grafting was associated with the greatest improvement in LVEF. Left ventricular end-systolic volume (or diameter), New York Heart Association functional classification, quality of life, and exercise capacity were also improved in most studies after cell therapy. Most ICM trials demonstrated a significant improvement in perfusion defects, infarct size, and myocardial viability. Several larger clinical trials that are in progress employ alternative delivery modes, cell types, and longer follow-up periods. Stem cells are a promising therapeutic modality for patients with heart failure due to ICM or NICM. More data are required from larger blinded trials to determine which combination of cell type and delivery mode will yield the most benefit with avoidance of harm in these patient populations.

Renal biomarkers and outcomes in outpatients with heart failure: The Atlanta cardiomyopathy consortium.

BACKGROUND/OBJECTIVES: Cystatin-C and beta-2-microglobulin may be superior to serum creatinine, blood urea nitrogen (BUN), or estimated glomerular filtration rate (eGFR) in patients hospitalized with heart failure (HF). We compared these renal markers in ambulatory HF patients. METHODS: We prospectively evaluated the association of baseline renal markers and eGFR (by 4 different formulas) with (1) the composite of death or HF-related hospitalization and (2) rates of hospitalizations and emergency department (ED) visits in 166 outpatients with HF (57.3±11.6years; 57.2% white, 38.6% black, median left ventricular ejection fraction 27.5% [17.5, 40.0]). RESULTS: After a median of 3.9years, 63 (38.0%) patients met the composite endpoint. There were 458 hospitalizations (177 [38.6%] for HF) and 209 ED visits (51 [24.4%] for HF). Cystatin-based eGFR most consistently predicted (1) the composite endpoint (highest-to-lowest tertile adjusted hazard ratio [HR] 4.92 [95% CI 2.07-11.7; P<0.001]); and (2) hospitalization rates, including HF hospitalizations (highest-to-lowest tertile, adjusted relative rate 5.24 [95% CI 1.61-17.01; P=0.006]). Serum creatinine alone was a strong predictor of the composite endpoint (highest-to-lowest tertile, adjusted HR 3.20 [95% CI, 1.51-6.78; P=0.002]). Only the highest tertile of BUN was associated with rates of ED visits. CONCLUSIONS: In outpatients with HF, cystatin-based eGFR provides consistent prognostication across outcomes, except ED visits. Serum creatinine is an adequate prognosticator of death or HF hospitalization.

Pulmonary function testing and outcomes in subjects with heart failure listed for heart transplantation.

BACKGROUND: Impaired spirometric parameters have been reported in patients with stage C heart failure and portend worse outcomes in these patients. The impact of spirometric parameters on outcomes in patients with stage D heart failure listed for heart transplantation is unknown. METHODS: We collected data on consecutive subjects listed for heart transplantation and examined the association of FEV1, FVC, and FEV1/FVC with (1) death or left ventricular assist device implantation (primary end point) and (2) death, left ventricular assist device implantation, or urgent transplantation (secondary end point). In a secondary analysis, we examined the association of baseline spirometry with post-transplant outcomes. RESULTS: Among 187 subjects (53 ± 10 y old, 17.1% women, 69.5% white subjects, 28.9% black subjects), there were 19 deaths, 28 left ventricular assist device implantations, and 74 urgent transplantations (primary end point of 25.1%, secondary end point of 64.7%) after a median of 5.5 months (interquartile range of 2.3-15.2). For FEV1, the hazard ratios for the primary and secondary end points were 0.93 (95% CI 0.61-1.41, P = .72) and 0.94 (95% CI 0.72-1.21, P = .62) per L, respectively. The hazard ratios of FVC were 0.90 (95% CI 0.65-1.25, P = .52) and 0.92 (95% CI 0.76-1.13, P = .43) per L, respectively. Impairment patterns (obstructive, restrictive, mixed) were not associated with risk for events. There was no interaction of spirometric parameters with smoking or lung disease for outcomes. Baseline spirometry was not associated with perioperative 30-d mortality (1.4%) and 1-y post-transplant survival (97.1%). CONCLUSIONS: In contrast to stage C subjects with heart failure, spirometric parameters were not associated with outcomes in this homogeneous stage D heart failure population.

Echocardiographic assessment of pulmonary artery systolic pressure and outcomes in ambulatory heart failure patients.

BACKGROUND: Pulmonary hypertension (PH) in patients with heart failure (HF) is associated with worse outcomes and is rapidly being recognized as a therapeutic target. To facilitate pragmatic research efforts, data regarding the prognostic importance of noninvasively assessed pulmonary artery systolic pressure (PASP) in stable ambulatory patients with HF are needed. METHODS AND RESULTS: We examined the association between echocardiographic PASP and outcomes in 417 outpatients with HF (age, 54 ± 13 years; 60.7% men; 50.4% whites; 24.9% with preserved ejection fraction). Median PASP was 36 mm Hg (interquartile range [IQR]: 29, 46). After a median follow-up of 2.6 years (IQR: 1.7, 3.9) there were 72 major events (57 deaths; 9 urgent heart transplants; and 6 ventricular assist device implantations) and 431 hospitalizations for HF. In models adjusting for clinical risk factors and therapy, a 10-mm Hg higher PASP was associated with 37% higher risk (95% CI: 18, 59; P<0.001) for major events, and 11% higher risk (95% CI: 1, 23; P=0.039) for major events or HF hospitalization. The threshold that maximized the likelihood ratio for both endpoints was 48 mm Hg; those with PASP ≥ 48 mm Hg (N=84; 20.1%) had an adjusted hazard ratio of 3.33 (95% CI: 1.96, 5.65; P<0.001) for major events and 1.47 (95% CI: 1.02, 2.11; P=0.037) for major events or HF hospitalization. Reduced right ventricular systolic function had independent prognostic utility over PASP for adverse outcomes. Right atrial pressure and transtricuspid gradient both contributed to risk. CONCLUSIONS: Elevated PASP, determined by echocardiography, identifies ambulatory patients with HF at increased risk for adverse events.

Prevalence of resistant hypertension and eligibility for catheter-based renal denervation in hypertensive outpatients.

BACKGROUND: Studies of endovascular renal denervation (RDN) have demonstrated significant blood pressure reduction in eligible patients with resistant hypertension. These trials have used stringent inclusion and exclusion criteria in patient enrollment, potentially selecting for a small subset of patients with resistant hypertension. In this study, we examined the changes in estimated prevalence of resistant hypertension when using increasingly stringent definitions of resistant hypertension in a fixed population and assessed the generalizability of RDN when applying study criteria to a community-based hypertensive population. METHODS: A retrospective chart review was done of hypertensive outpatients. Four increasingly stringent interpretations of the American Heart Association definition of resistant hypertension were used to calculate prevalence estimates. Patients eligible for RDN were identified using criteria from SYMPLICITY HTN-3. Demographic and clinical characteristics were compared. RESULTS: We identified 1,756 hypertensive outpatients; 55.0% were male, 53.9% were white, and subjects had a mean age of 66.6 ± 12.5 years and a body mass index (BMI) of 30.1 ± 10.7 kg/m(2). Only 14 (0.8%) were eligible for RDN. Among these patients, 10 (71.4%) were female and all were black, with a mean age of 69.9 ± 8.8 and BMI of 35.7 ± 6.6. Congestive heart failure was more common in patients eligible for RDN. CONCLUSIONS: Patients eligible for RDN based on published studies represent an exceedingly small proportion of the total hypertensive population. Further studies are necessary to determine if the benefits of RDN can be generalized to a broader range of hypertensive patients than those included in previous trials.

Patient-reported selective adherence to heart failure self-care recommendations: a prospective cohort study: the Atlanta Cardiomyopathy Consortium.

Simultaneous adherence with multiple self-care instructions among heart failure (HF) patients is not well described. Patient-reported adherence to 8 recommendations related to exercise, alcohol, medications, smoking, diet, weight, and symptoms was assessed among 308 HF patients using the Medical Outcomes Study Specific Adherence Scale questionnaire (0="never" to 5="always," maximum score=40). A baseline cumulative score of ≥32/40 (average ≥80%) defined good adherence. Clinical events (death/transplantation/ventricular assist device), resource utilization, functional capacity (6-minute walk distance), and health status (Kansas City Cardiomyopathy Questionnaire [KCCQ]) were compared among patients with and without good adherence. The mean follow-up was 2.0±1.0 years, and adherence ranged from 26.3% (exercise) to 89.9% (medications). A cumulative score indicating good adherence was reported by 35.7%, whereas good adherence with every behavior was reported by 9.1% of patients. Good adherence was associated with fewer hospitalizations (all-cause 87.8 vs 107.6; P=.018; HF 29.6 vs 43.8; P=.007) and hospitalized days (all-cause 422 vs 465; P=.015; HF 228 vs 282; P<.001) per 100-person-years and better health status (KCCQ overall score 70.1±24.6 vs 63.8±22.8; P=.011). Adherence was not associated with clinical events or functional capacity. Patient-reported adherence with HF self-care recommendations is alarmingly low and selective. Good adherence was associated with lower resource utilization and better health status.

Right ventricular function with standard and speckle-tracking echocardiography and clinical events in adults with D-transposition of the great arteries post atrial switch.

BACKGROUND: The prognostic value of deformation parameters of the systemic right ventricle in adults with D-transposition of the great arteries and prior atrial switch has not been reported. METHODS: Sixty-four adults with D-transposition of the great arteries and prior atrial switch (mean age, 29 ± 6 years; 22 women; mean right ventricular [RV] fractional area change, 22.9 ± 7.5%; 31 with pacemakers at baseline) and no histories of heart failure or ventricular tachycardia were prospectively evaluated. Global longitudinal strain (GS), global systolic strain rate (GSRs), and global early diastolic strain rate (GSRe) of the right ventricle were measured using speckle tracking from apical views and compared with standard parameters of RV function (fractional area change, tricuspid annular plane systolic excursion, tissue Doppler velocities, and isovolumic acceleration) for association with and potential prediction of clinical events, defined as incident stage C heart failure or ventricular tachycardia. RESULTS: Baseline RV GS, GSRs, and GSRe were -12.5 ± 3.0%, -0.59 ± 0.14 sec(-1), and 0.68 ± 0.22 sec(-1), respectively. After a median of 2.4 years (interquartile range, 1.5-4.1 years), 12 patients (19%) presented with clinical events (heart failure in 11 patients, ventricular tachycardia in one patient). In Cox models, RV GS had the strongest association with clinical events (hazard ratio [HR] per 1%, 1.35; 95% confidence interval [CI], 1.14-1.58; P < .001), followed by GSRs (HR per 0.01 sec(-1), 1.06; 95% CI, 1.02-1.11; P = .006), GSRe (HR per -0.01 sec(-1), 1.04; 95% CI, 1.00-1.07; P = .031), and fractional area change (HR per -1%, 1.08; 95% CI, 1.00-1.17; P = .047). Other measures of RV function were not significantly associated with risk for events. In receiver operating characteristic analysis, RV GS ≥ -10% optimally predicted future events (C = 0.83; 95% CI, 0.71-0.91; P < .001). CONCLUSIONS: Reduced longitudinal GS of the systemic right ventricle is associated with increased risk for clinical events among patients with D-transposition of the great arteries and prior atrial switch.