Risk of Cardiac Arrhythmias Among Climbers on Mount Everest.

Importance: Arterial hypoxemia, electrolyte imbalances, and periodic breathing increase the vulnerability to cardiac arrhythmia at altitude. Objective: To explore the incidence of tachyarrhythmias and bradyarrhythmias in healthy individuals at high altitudes. Design, Setting, and Participants: This prospective cohort study involved healthy individuals at altitude (8849 m) on Mount Everest, Nepal. Recruitment occurred from January 25 to May 9, 2023, and data analysis took place from June to July 2023. Exposure: All study participants underwent 12-lead electrocardiogram, transthoracic echocardiography, and exercise stress testing before and ambulatory rhythm recording both before and during the expedition. Main Outcome: The incidence of a composite of supraventricular (>30 seconds) and ventricular (>3 beats) tachyarrhythmia and bradyarrhythmia (sinoatrial arrest, second- or third-degree atrioventricular block). Results: Of the 41 individuals recruited, 100% were male, and the mean (SD) age was 33.6 (8.9) years. On baseline investigations, there were no signs of exertional ischemia, wall motion abnormality, or cardiac arrhythmia in any of the participants. Among 34 individuals reaching basecamp at 5300 m, 32 participants climbed to 7900 m or higher, and 14 reached the summit of Mount Everest. A total of 45 primary end point-relevant events were recorded in 13 individuals (38.2%). Forty-three bradyarrhythmic events were documented in 13 individuals (38.2%) and 2 ventricular tachycardias in 2 individuals (5.9%). Nine arrhythmias (20%) in 5 participants occurred when climbers were using supplemental bottled oxygen, whereas 36 events (80%) in 11 participants occurred at lower altitudes when no supplemental bottled oxygen was used. The proportion of individuals with arrhythmia remained stable across levels of increasing altitude, while event rates per 24 hours numerically increased between 5300 m (0.16 per 24 hours) and 7300 m (0.37 per 24 hours) before decreasing again at higher altitudes, where supplemental oxygen was used. None of the study participants reported dizziness or syncope. Conclusion and Relevance: In this study, more than 1 in 3 healthy individuals experienced cardiac arrhythmia during the climb of Mount Everest, thereby confirming the association between exposure to high altitude and incidence of cardiac arrhythmia. Future studies should explore the potential implications of these rhythm disturbances.

Sex-specific differences in physiological parameters related to SARS-CoV-2 infections among a national cohort (COVI-GAPP study).

Considering sex as a biological variable in modern digital health solutions, we investigated sex-specific differences in the trajectory of four physiological parameters across a COVID-19 infection. A wearable medical device measured breathing rate, heart rate, heart rate variability, and wrist skin temperature in 1163 participants (mean age = 44.1 years, standard deviation [SD] = 5.6; 667 [57%] females). Participants reported daily symptoms and confounders in a complementary app. A machine learning algorithm retrospectively ingested daily biophysical parameters to detect COVID-19 infections. COVID-19 serology samples were collected from all participants at baseline and follow-up. We analysed potential sex-specific differences in physiology and antibody titres using multilevel modelling and t-tests. Over 1.5 million hours of physiological data were recorded. During the symptomatic period of infection, men demonstrated larger increases in skin temperature, breathing rate, and heart rate as well as larger decreases in heart rate variability than women. The COVID-19 infection detection algorithm performed similarly well for men and women. Our study belongs to the first research to provide evidence for differential physiological responses to COVID-19 between females and males, highlighting the potential of wearable technology to inform future precision medicine approaches.

Comparator Data Characteristics and Testing Procedures for the Clinical Performance Evaluation of Continuous Glucose Monitoring Systems.

Comparing the performance of different continuous glucose monitoring (CGM) systems is challenging due to the lack of comprehensive guidelines for clinical study design. In particular, the absence of concise requirements for the distribution of comparator (reference) blood glucose (BG) concentrations and their rate of change (RoC) that are used to evaluate CGM performance, impairs comparability. For this article, several experts in the field of CGM performance testing have collaborated to propose characteristics of the distribution of comparator measurements that should be collected during CGM performance testing. Specifically, it is proposed that at least 7.5% of comparator BG concentrations are <70 mg/dL (3.9 mmol/L) and >300 mg/dL (16.7 mmol/L), respectively, and that at least 7.5% of BG-RoC combinations indicate fast BG changes with impending hypo- or hyperglycemia, respectively. These proposed characteristics of the comparator data can facilitate the harmonization of testing conditions across different studies and CGM systems and ensure that the most relevant scenarios representing real-life situations are established during performance testing. In addition, a study protocol and testing procedure for the manipulation of glucose levels are suggested that enable the collection of comparator data with these characteristics. This work is an important step toward establishing a future standard for the performance evaluation of CGM systems.

Can Wrist-Worn Medical Devices Correctly Identify Ovulation?

(1) Background: Hormonal fluctuations across the menstrual cycle lead to multiple changes in physiological parameters such as body temperature, cardiovascular function, respiratory rate and perfusion. Electronic wearables analyzing those parameters might present a convenient alternative to urinary ovulation tests for predicting the fertile window. (2) Methods: We conducted a prospective observational study including women aged 18-45 years without current hormonal therapy who used a wrist-worn medical device and urinary ovulation tests for a minimum of three cycles. We analyzed the accuracy of both the retrospective and prospective algorithms using a generalized linear mixed-effects model. The findings were compared to real-world data from bracelet users who also reported urinary ovulation tests. (3) Results: A total of 61 study participants contributing 205 cycles and 6081 real-life cycles from 3268 bracelet users were included in the analysis. The mean error in identifying ovulation with the wrist-worn medical device retrospective algorithm in the clinical study was 0.31 days (95% CI -0.13 to 0.75). The retrospective algorithm identified 75.4% of fertile days, and the prospective algorithm identified 73.8% of fertile days correctly within the pre-specified equivalence limits (±2 days). The quality of the retrospective algorithm in the clinical study could be confirmed by real-world data. (4) Conclusion: Our data indicate that wearable sensors may be used to accurately detect the periovulatory period.

Changes in Heart Rate, Heart Rate Variability, Breathing Rate, and Skin Temperature throughout Pregnancy and the Impact of Emotions-A Longitudinal Evaluation Using a Sensor Bracelet.

(1) Background: Basic vital signs change during normal pregnancy as they reflect the adaptation of maternal physiology. Electronic wearables like fitness bracelets have the potential to provide vital signs continuously in the home environment of pregnant women. (2) Methods: We performed a prospective observational study from November 2019 to November 2020 including healthy pregnant women, who recorded their wrist skin temperature, heart rate, heart rate variability, and breathing rate using an electronic wearable. In addition, eight emotions were assessed weekly using five-point Likert scales. Descriptive statistics and a multivariate model were applied to correlate the physiological parameters with maternal emotions. (3) Results: We analyzed data from 23 women using the electronic wearable during pregnancy. We calculated standard curves for each physiological parameter, which partially differed from the literature. We showed a significant association of several emotions like feeling stressed, tired, or happy with the course of physiological parameters. (4) Conclusions: Our data indicate that electronic wearables are helpful for closely observing vital signs in pregnancy and to establish modern curves for the physiological course of these parameters. In addition to physiological adaptation mechanisms and pregnancy disorders, emotions have the potential to influence the course of physiological parameters in pregnancy.

Wearable sensors for prediction of intraamniotic infection in women with preterm premature rupture of membranes: a prospective proof of principle study.

PURPOSE: To evaluate the use of wearable sensors for prediction of intraamniotic infection in pregnant women with PPROM. MATERIALS AND METHODS: In a prospective proof of principle study, we included 50 patients diagnosed with PPROM at the University Hospital Zurich between November 2017 and May 2020. Patients were instructed to wear a bracelet during the night, which measures physiological parameters including wrist skin temperature, heart rate, heart rate variability, and breathing rate. A two-way repeated measures ANOVA was performed to evaluate the difference over time of both the wearable device measured parameters and standard clinical monitoring values, such as body temperature, pulse, leucocytes, and C-reactive protein, between women with and without intraamniotic infection. RESULTS: Altogether, 23 patients (46%) were diagnosed with intraamniotic infection. Regarding the physiological parameters measured with the bracelet, we observed a significant difference in breathing rate (19 vs 16 per min, P < .01) and heart rate (72 vs 67 beats per min, P = .03) in women with intraamniotic infection compared to those without during the 3 days prior to birth. In parallel to these changes standard clinical monitoring values were significantly different in the intraamniotic infection group compared to women without infection in the 3 days preceding birth. CONCLUSION: Our results suggest that wearable sensors are a promising, noninvasive, patient friendly approach to support the early detection of intraamniotic infection in women with PPROM. However, confirmation of our findings in larger studies is required before implementing this technique in standard clinical management.

A Statistical Approach for Assessing the Compliance of Integrated Continuous Glucose Monitoring Systems with Food and Drug Administration Accuracy Requirements.

To assess the compliance of "integrated" continuous glucose monitoring (CGM) systems with U.S. Food and Drug Administration requirements, the calculation of confidence intervals (CIs) on agreement rates (ARs), that is, the percentage of CGM measurements lying within a certain deviation of a comparator method, is stipulated. However, despite the existence of numerous approaches that could yield different results, a specific procedure for calculating CIs is not described anywhere. This report, therefore, proposes a suitable statistical procedure to allow transparency and comparability between CGM systems. Three existing methods were applied to six data sets from different CGM performance studies. The results indicate that a bootstrap-based method that accounts for the clustered structure of CGM data is reliable and robust. We thus recommend its use for the estimation of CIs of ARs. A software implementation of the proposed method is freely available (https://github.com/IfDTUlm/CGM_Performance_Assessment).

Continuous Glucose Deviation Interval and Variability Analysis (CG-DIVA): A Novel Approach for the Statistical Accuracy Assessment of Continuous Glucose Monitoring Systems.

BACKGROUND: The accuracy of continuous glucose monitoring (CGM) systems is crucial for the management of glucose levels in individuals with diabetes mellitus. However, the discussion of CGM accuracy is challenged by an abundance of parameters and assessment methods. The aim of this article is to introduce the Continuous Glucose Deviation Interval and Variability Analysis (CG-DIVA), a new approach for a comprehensive characterization of CGM point accuracy which is based on the U.S. Food and Drug Administration requirements for "integrated" CGM systems. METHODS: The statistical concept of tolerance intervals and data from two approved CGM systems was used to illustrate the CG-DIVA. RESULTS: The CG-DIVA characterizes the expected range of deviations of the CGM system from a comparison method in different glucose concentration ranges and the variability of accuracy within and between sensors. The results of the CG-DIVA are visualized in an intuitive and straightforward graphical presentation. Compared with conventional accuracy characterizations, the CG-DIVA infers the expected accuracy of a CGM system and highlights important differences between CGM systems. Furthermore, it provides information on the incidence of large errors which are of particular clinical relevance. A software implementation of the CG-DIVA is freely available (https://github.com/IfDTUlm/CGM_Performance_Assessment). CONCLUSIONS: We argue that the CG-DIVA can simplify the discussion and comparison of CGM accuracy and could replace the high number of conventional approaches. Future adaptations of the approach could thus become a putative standard for the accuracy characterization of CGM systems and serve as the basis for the definition of future CGM performance requirements.

Investigation of the use of a sensor bracelet for the presymptomatic detection of changes in physiological parameters related to COVID-19: an interim analysis of a prospective cohort study (COVI-GAPP).

OBJECTIVES: We investigated machinelearningbased identification of presymptomatic COVID-19 and detection of infection-related changes in physiology using a wearable device. DESIGN: Interim analysis of a prospective cohort study. SETTING, PARTICIPANTS AND INTERVENTIONS: Participants from a national cohort study in Liechtenstein were included. Nightly they wore the Ava-bracelet that measured respiratory rate (RR), heart rate (HR), HR variability (HRV), wrist-skin temperature (WST) and skin perfusion. SARS-CoV-2 infection was diagnosed by molecular and/or serological assays. RESULTS: A total of 1.5 million hours of physiological data were recorded from 1163 participants (mean age 44±5.5 years). COVID-19 was confirmed in 127 participants of which, 66 (52%) had worn their device from baseline to symptom onset (SO) and were included in this analysis. Multi-level modelling revealed significant changes in five (RR, HR, HRV, HRV ratio and WST) device-measured physiological parameters during the incubation, presymptomatic, symptomatic and recovery periods of COVID-19 compared with baseline. The training set represented an 8-day long instance extracted from day 10 to day 2 before SO. The training set consisted of 40 days measurements from 66 participants. Based on a random split, the test set included 30% of participants and 70% were selected for the training set. The developed long short-term memory (LSTM) based recurrent neural network (RNN) algorithm had a recall (sensitivity) of 0.73 in the training set and 0.68 in the testing set when detecting COVID-19 up to 2 days prior to SO. CONCLUSION: Wearable sensor technology can enable COVID-19 detection during the presymptomatic period. Our proposed RNN algorithm identified 68% of COVID-19 positive participants 2 days prior to SO and will be further trained and validated in a randomised, single-blinded, two-period, two-sequence crossover trial. Trial registration number ISRCTN51255782; Pre-results.

Prevalence of latent structural heart disease in Nepali schoolchildren.

BACKGROUND: The present study aimed to quantify the burden of structural heart disease in Nepali children. METHODS: We performed a school-based cross-sectional echocardiographic screening study with cluster random sampling among children 5-16 years of age. RESULTS: Between December 2012 and January 2019, 6573 children (mean age 10.6 ± 2.9 years) from 41 randomly selected schools underwent echocardiographic screening. Structural heart disease was detected in 14.0 per 1000 children (95% CI 11.3-17.1) and was congenital in 3.3 per 1000 (95% CI 2.1-5.1) and rheumatic in 10.6 per 1000 (95% CI 8.3-13.4). Rates of rheumatic heart disease were higher among children attending public as compared to private schools (OR 2.8, 95% CI 1.6-5.2, p = 0.0001). CONCLUSION: Rheumatic heart disease accounted for three out of four cases of structural heart disease and was more common among children attending public as compared to private schools.

The Accuracy of Wrist Skin Temperature in Detecting Ovulation Compared to Basal Body Temperature: Prospective Comparative Diagnostic Accuracy Study.

BACKGROUND: As a daily point measurement, basal body temperature (BBT) might not be able to capture the temperature shift in the menstrual cycle because a single temperature measurement is present on the sliding scale of the circadian rhythm. Wrist skin temperature measured continuously during sleep has the potential to overcome this limitation. OBJECTIVE: This study compares the diagnostic accuracy of these two temperatures for detecting ovulation and to investigate the correlation and agreement between these two temperatures in describing thermal changes in menstrual cycles. METHODS: This prospective study included 193 cycles (170 ovulatory and 23 anovulatory) collected from 57 healthy women. Participants wore a wearable device (Ava Fertility Tracker bracelet 2.0) that continuously measured the wrist skin temperature during sleep. Daily BBT was measured orally and immediately upon waking up using a computerized fertility tracker with a digital thermometer (Lady-Comp). An at-home luteinizing hormone test was used as the reference standard for ovulation. The diagnostic accuracy of using at least one temperature shift detected by the two temperatures in detecting ovulation was evaluated. For ovulatory cycles, repeated measures correlation was used to examine the correlation between the two temperatures, and mixed effect models were used to determine the agreement between the two temperature curves at different menstrual phases. RESULTS: Wrist skin temperature was more sensitive than BBT (sensitivity 0.62 vs 0.23; P<.001) and had a higher true-positive rate (54.9% vs 20.2%) for detecting ovulation; however, it also had a higher false-positive rate (8.8% vs 3.6%), resulting in lower specificity (0.26 vs 0.70; P=.002). The probability that ovulation occurred when at least one temperature shift was detected was 86.2% for wrist skin temperature and 84.8% for BBT. Both temperatures had low negative predictive values (8.8% for wrist skin temperature and 10.9% for BBT). Significant positive correlation between the two temperatures was only found in the follicular phase (rmcorr correlation coefficient=0.294; P=.001). Both temperatures increased during the postovulatory phase with a greater increase in the wrist skin temperature (range of increase: 0.50 °C vs 0.20 °C). During the menstrual phase, the wrist skin temperature exhibited a greater and more rapid decrease (from 36.13 °C to 35.80 °C) than BBT (from 36.31 °C to 36.27 °C). During the preovulatory phase, there were minimal changes in both temperatures and small variations in the estimated daily difference between the two temperatures, indicating an agreement between the two curves. CONCLUSIONS: For women interested in maximizing the chances of pregnancy, wrist skin temperature continuously measured during sleep is more sensitive than BBT for detecting ovulation. The difference in the diagnostic accuracy of these methods was likely attributed to the greater temperature increase in the postovulatory phase and greater temperature decrease during the menstrual phase for the wrist skin temperatures.

Mid-term outcome of children with latent rheumatic heart disease in eastern Nepal.

INTRODUCTION: Systematic echocardiographic screening of children in regions with an endemic pattern of rheumatic heart disease allows for the early detection of valvular lesions suggestive of subclinical rheumatic heart disease. The natural course of latent rheumatic heart disease is, however, incompletely understood at this time. METHODS: We performed a prospective cohort study of children detected to have echocardiographic evidence of definite or borderline rheumatic heart disease according to the World Heart Federation Criteria. RESULTS: Among 53 children found to have definite (36) or borderline (17) rheumatic heart disease, 44 (83%) children underwent follow-up at a median of 1.9 years (IQR 1.1-4.5). The median age of the children was 11 years (IQR 9-14) and 34 (64.2%) were girls. Among children with definite rheumatic heart disease, 21 (58.3%) were adherent to secondary antibiotic prophylaxis, 7 (19.4%) were not, information on adherence was missing in 2 (5.6%) children and 6 (16.7%) were lost to follow-up. Regression of disease was observed in 10 children (27.8%), whereas 20 children (55.6%) had stable disease. Among children adherent to secondary prophylaxis, seven (33.3%) showed regression of disease. Among children with borderline disease, seven (41.2%) showed regression of disease, three (17.6%) progression of disease, four (23.5%) remained stable and three (17.6%) were lost to follow-up. On univariate analysis, we identified no predictors of disease regression, and no predictors for lost to follow-up or non-adherence with secondary antibiotic prophylaxis. CONCLUSION: Definite rheumatic heart disease showed regression in one in four children. Borderline disease was spontaneously reversible in less than half of the children and progressed to definite rheumatic heart disease in one in five children. TRIAL REGISTRATION NUMBER: NCT01550068.

Biodegradable polymer sirolimus-eluting stents vs durable polymer everolimus-eluting stents in patients undergoing percutaneous coronary intervention: A meta-analysis of individual patient data from 5 randomized trials.

BACKGROUND: Newest generation drug-eluting stents combine biodegradable polymers with ultrathin stent platforms in order to minimize vessel injury and inflammatory response. Evidence from randomized controlled trials suggested that differences in stent design translate into differences in clinical outcome. The aim of the present study was to evaluate the safety and efficacy of ultrathin strut, biodegradable polymer sirolimus eluting stents (BP SES) compared with thin strut, durable polymer everolimus-eluting stents (DP EES) among patients undergoing percutaneous coronary intervention (PCI). METHODS: We pooled individual participant data from 5 randomized trials (NCT01356888, NCT01939249, NCT02389946, NCT01443104, NCT02579031) including a total of 5,780 patients, and performed a one-stage meta-analysis using a mixed effects Cox regression model. RESULTS: At a median duration of follow-up of 739 days (interquartile range 365-1,806 days), target-lesion failure occurred in 337 (10.3%) and 304 (12.2%) patients treated with BP SES and DP EES (HR 0.86, 95%CI 0.71-1.06, P = .16). There were no significant differences between BP SES and DP EES with regards to cardiac death (111 (3.4%) vs 102 (4.1%); HR 1.05, 95%CI 0.80-1.37, P = .73), target-vessel myocardial infarction (136 (4.1%) vs 126 (5.0%), HR 0.79, 95%CI 0.62-1.01, P = .061), and clinically-driven target-lesion revascularization (163 (5.0%) vs 147 (5.9%); HR 0.94, 95%CI 0.75-1.18, P = .61). The effect was consistent across major subgroups. In a landmark analysis, there was no significant interaction between treatment effect and timing of events. CONCLUSIONS: In this patient-level meta-analysis of 5 randomized controlled trials, BP SES were associated with a similar risk of target-lesion failure compared with DP EES among patients undergoing PCI. STUDY REGISTRATION: PROSPERO registry (CRD42018109098).

Effectiveness of Systematic Echocardiographic Screening for Rheumatic Heart Disease in Nepalese Schoolchildren: A Cluster Randomized Clinical Trial.

Importance: Echocardiographic screening allows for early detection of subclinical stages of rheumatic heart disease among children in endemic regions. Objective: To investigate the effectiveness of systematic echocardiographic screening in combination with secondary antibiotic prophylaxis on the prevalence of rheumatic heart disease. Design, Setting, and Participants: This cluster randomized clinical trial included students 9 to 16 years of age attending public and private schools in urban and rural areas of the Sunsari district in Nepal that had been randomly selected on November 17, 2012. Echocardiographic follow-up was performed between January 7, 2016, and January 3, 2019. Interventions: In the experimental group, children underwent systematic echocardiographic screening followed by secondary antibiotic prophylaxis in case they had echocardiographic evidence of latent rheumatic heart disease. In the control group, children underwent no echocardiographic screening. Main Outcomes and Measures: Prevalence of the composite of definite or borderline rheumatic heart disease according to the World Heart Federation criteria in experimental and control schools as assessed 4 years after intervention. Results: A total of 35 schools were randomized to the experimental group (n = 19) or the control group (n = 16). After a median of 4.3 years (interquartile range [IQR], 4.0-4.5 years), 17 of 19 schools in the experimental group (2648 children; median age at follow-up, 12.1 years; IQR, 10.3-12.5 years; 1308 [49.4%] male) and 15 of 16 schools in the control group (1325 children; median age at follow-up, 10.6 years; IQR, 10.0-12.5 years; 682 [51.5%] male) underwent echocardiographic follow-up. The prevalence of definite or borderline rheumatic heart disease was 10.8 per 1000 children (95% CI, 4.7-24.7) in the control group and 3.8 per 1000 children (95% CI, 1.5-9.8) in the experimental group (odds ratio, 0.34; 95% CI, 0.11-1.07; P = .06). The prevalence in the experimental group at baseline had been 12.9 per 1000 children (95% CI, 9.2-18.1). In the experimental group, the odds ratio of definite or borderline rheumatic heart disease at follow-up vs baseline was 0.29 (95% CI, 0.13-0.65; P = .008). Conclusions and Relevance: School-based echocardiographic screening in combination with secondary antibiotic prophylaxis in children with evidence of latent rheumatic heart disease may be an effective strategy to reduce the prevalence of definite or borderline rheumatic heart disease in endemic regions. Trial Registration: ClinicalTrials.gov Identifier: NCT01550068.

Effets du climat et des interventions de santé publique sur la pandémie de COVID-19 : une étude de cohorte prospective.

CONTEXTE: On ignore si les variations climatiques saisonnières, la fermeture des établissements scolaires ou d'autres interventions de santé publique entraîneront un ralentissement de la pandémie actuelle de maladie à coronavirus 2019 (COVID-19). Nous avons voulu déterminer si de façon globale la progression de l'épidémie est associée au climat ou aux interventions de santé publique visant à réduire la transmission du coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2). MÉTHODES: Nous avons procédé à une étude de cohorte prospective des 144 régions géopolitiques de la planète (375 609 cas) présentant au moins 10 cas de COVID-19, avec transmission locale, en date du 20 mars 2020, à l'exclusion de la Chine, de la Corée du Sud, de l'Iran et de l'Italie. Par analyse de régression à effets aléatoires pondérée, nous avons évalué le lien entre la progression de l'épidémie (exprimée sous forme de rapports de taux d'incidence [RTI] comparant les nombres cumulatifs de cas de COVID-19 du 27 mars 2020 à ceux du 20 mars 2020) avec les facteurs de latitude, température, humidité, fermeture des établissements scolaires, interdiction des grands rassemblements et mesures d'éloignement social qui étaient en place les 7 et 13 mars 2020 (période de 14 jours antérieure à l'évaluation). RÉSULTATS: Les analyses univariées ont révélé aucuns lien entre la progression de l'épidémie et les facteurs de latitude et de température, mais des liens négatifs faibles avec l'humidité relative (RTI par 10 %, 0,91, intervalle de confiance [IC] de 95 % 0,85­0,96) et l'humidité absolue (RTI par 5 g/m3 0,92, IC à 95 % 0,85­0,99). Des liens étroits ont été observés avec l'interdiction des grands rassemblements (RTI 0,65, IC à 95 % 0,53­0,79), la fermeture des établissements scolaires (RTI 0,63, IC à 95 % 0,52­0,78) et les mesures d'éloignement social (RTI 0,62, IC à 95 % 0,45­0,85). Dans un modèle multivarié, on a noté un lien étroit avec le nombre de mesures déployées par la santé publique (p pour tendance = 0,001), tandis que le lien avec l'humidité absolue s'atténuait. INTERPRÉTATION: La progression de l'épidémie de COVID-19 ne s'est pas révélée en lien avec la latitude ni avec la température, mais faiblement en lien avec l'humidité relative ou absolue. À l'inverse, les interventions de santé publique ont été étroitement associées à un ralentissement de la progression de l'épidémie.

Impact of climate and public health interventions on the COVID-19 pandemic: a prospective cohort study.

BACKGROUND: It is unclear whether seasonal changes, school closures or other public health interventions will result in a slowdown of the current coronavirus disease 2019 (COVID-19) pandemic. We aimed to determine whether epidemic growth is globally associated with climate or public health interventions intended to reduce transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: We performed a prospective cohort study of all 144 geopolitical areas worldwide (375 609 cases) with at least 10 COVID-19 cases and local transmission by Mar. 20, 2020, excluding China, South Korea, Iran and Italy. Using weighted random-effects regression, we determined the association between epidemic growth (expressed as ratios of rate ratios [RRR] comparing cumulative counts of COVID-19 cases on Mar. 27, 2020, with cumulative counts on Mar. 20, 2020) and latitude, temperature, humidity, school closures, restrictions of mass gatherings, and measures of social distancing during an exposure period 14 days previously (Mar. 7 to 13, 2020). RESULTS: In univariate analyses, there were no associations of epidemic growth with latitude and temperature, but weak negative associations with relative humidity (RRR per 10% 0.91, 95% confidence interval [CI] 0.85-0.96) and absolute humidity (RRR per 5 g/m3 0.92, 95% CI 0.85-0.99). Strong associations were found for restrictions of mass gatherings (RRR 0.65, 95% CI 0.53-0.79), school closures (RRR 0.63, 95% CI 0.52-0.78) and measures of social distancing (RRR 0.62, 95% CI 0.45-0.85). In a multivariable model, there was a strong association with the number of implemented public health interventions (p for trend = 0.001), whereas the association with absolute humidity was no longer significant. INTERPRETATION: Epidemic growth of COVID-19 was not associated with latitude and temperature, but may be associated weakly with relative or absolute humidity. Conversely, public health interventions were strongly associated with reduced epidemic growth.

Clinical outcomes in high-risk patients with a severe aortic stenosis: a seven-year follow-up analysis.

INTRODUCTION: The aim of this study was to assess the clinical outcomes of high-risk patients with severe aortic stenosis (AS) allocated to medical treatment (MT), transcatheter aortic valve replacement (TAVR), and surgical aortic valve replacement (SAVR) through extended follow-up. METHODS AND RESULTS: Consecutive patients with severe symptomatic AS included in a prospective single centre registry underwent sweep follow-up between March and August 2016. Clinical outcomes were assessed using a competing risk model. A total of 442 patients (median age 83 years; 52% female) were allocated to MT (n = 78), SAVR (n = 107), or TAVR (n = 257) with a gradient of surgical risk as assessed by logistic EuroSCORE (MT: 27.9 ± 14.5%, TAVR: 24.7 ± 24.9%, SAVR: 12.5 ± 8.2%; p <0.001). Survival after a median duration of follow-up of seven years was 6.4% (MT), 30.4% (TAVR), and 46.7% (SAVR), respectively (p <0.001). One TAVR and one SAVR patient underwent repeat intervention for valvular degeneration between 4.5 and 8.4 years after intervention. Compromised left ventricular function (LVEF <40%) was associated with increased mortality (HR 1.62, 95% CI 1.22–2.15; p <0.0001), whereas female sex was protective (HR 0.68, 95% CI 0.53–0.88; p = 0.0006). CONCLUSION: Both TAVR and SAVR reduced mortality compared to MT throughout a median duration of follow-up of seven years. Repeat interventions for valvular degeneration were rare.

Long-term outcomes with balloon-expandable and self-expandable prostheses in patients undergoing transfemoral transcatheter aortic valve implantation for severe aortic stenosis.

BACKGROUND: Data on long-term outcomes in patients undergoing transcatheter aortic valve implantation (TAVI) is scarce. METHODS: We investigated long term outcomes of consecutive patients undergoing TAVI with balloon- and self-expandable bioprostheses (Edwards SAPIEN (ESV), Edwards Lifesciences Inc., Irvine, CA, USA; Medtronic Corevalve system (MCS), Medtronic Inc., Minneapolis, MN, USA). RESULTS: Among 628 patients (mean age 82.4 ±â€¯5.8 years, 55% female), 489 (77.8%) underwent transfemoral TAVI. 309 (63.2%) patients received a MCS prosthesis, whereas 180 (36.8%) patients were treated with an ESV prosthesis. The median duration of follow-up amounted to 5.2 years (range 3.4-8.3 years). All-cause mortality did not differ between the two groups (MCS 46.9%, ESV 53.4%, CI 95%: RR 1.21 [0.93-1.57], P = 0.15), whereas cardiac mortality was higher in the ESV cohort after 5 years of follow-up (MCS 35.1%, ESV 45.4%, CI 95%: RR 1.37 [1.01-1.86], P = 0.04). Structural valve deterioration, which was on average diagnosed 41.9 months (range 18-60 months) after TAVI, occurred in 8 cases (1.6%), resulting in one repeat intervention. CONCLUSIONS: While half of all patients died within 5 years after TAVI with no significant differences in all-cause mortality, structural valve deterioration was documented in <2% of cases.

Comparison of intra-procedural vs. post-stenting prolonged bivalirudin infusion for residual thrombus burden in patients with ST-segment elevation myocardial infarction undergoing: the MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and angioX) OCT study.

AIMS: To compare prolonged bivalirudin infusion vs. an intra-procedural only bivalirudin infusion administration in subjects with ST-segment elevation myocardial infarction (STEMI) regarding residual stent strut thrombosis. METHODS AND RESULTS: Multivessel STEMI patients undergoing primary percutaneous coronary intervention (PPCI) and scheduled for a staged percutaneous coronary intervention (PCI) before hospital discharge were selected among those allocated to either prolonged bivalirudin or intra-procedural only bivalirudin infusion in the MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and angioX) Treatment-Duration study. Optical coherence tomography (OCT) of the infarct-related artery was performed at the end of PPCI and 4-5 days thereafter during staged intervention. The predefined endpoint was the percentage difference in the number of stent cross-sections with a thrombotic area >5% at the end of PPCI and at the time of staged PCI (ΔThCS). Between September 2013 and November 2015, 137 were randomized to either intra-procedural only bivalirudin infusion (N = 64) or prolonged bivalirudin (N = 73) at 16 European sites. Mean stent area, minimum lumen area, percentage of malapposed struts, and mean percent thrombotic area were comparable after index or staged PCI. The difference in the proportion of frames with percent thrombotic area >5% (ΔTh > 5%) were -7.7 (-22.1 to 5.1) in the intra-procedural bivalirudin infusion group and -8.8 (-23.1 to 2.6) in the prolonged infusion group (P = 0.994). Time from index to follow-up OCT imaging and the infarct vessel artery did not affect this OCT-based endpoint. CONCLUSION: A strategy of prolonged bivalirudin infusion after PPCI did not reduce residual stent strut thrombosis when compared with intra-procedural only bivalirudin infusion administration (funded by The Medicines Company and Terumo; MATRIX ClinicalTrials.gov number, NCT01433627).

Transcatheter aortic valve replacement in patients with concomitant mitral stenosis.

AIMS: Multivalvular disease is of increasing concern in elderly patients undergoing transcatheter aortic valve replacement (TAVR). The objective of the present analysis was to investigate the impact of concomitant mitral stenosis (MS) on clinical outcomes in patients undergoing TAVR for severe, symptomatic aortic stenosis (AS). METHODS AND RESULTS: Among 1339 patients undergoing TAVR between August 2007 and December 2015, adequate echocardiographic data for the assessment of severity and aetiology of MS was available in 971 (72.5%) patients. Patients were stratified according to degree and aetiology of concomitant MS. Mitral stenosis was documented in 176 (18.1%) TAVR patients (mean mitral valve area 1.9 ± 0.4 cm2) and considered degenerative in 110 (62.5%) and rheumatic in 66 (37.5%) patients, respectively. Mitral stenosis was categorized as moderate/severe in 28 patients (2.9%). Baseline characteristics were comparable between patients with vs. without MS. At 1 year, patients with MS were at increased risk of cardiovascular death [36 (21.4%) vs. 66 (8.7%); adjusted hazard ratio (HRadj) 3.64, 95% confidence interval (CI) 2.38-5.56] and disabling stroke [12 (7.1%) vs. 23 (3.0%); HRadj 2.98, 95% CI 1.46-6.09] as compared to patients without MS. Differences in cardiovascular death and disabling stroke emerged within 30 days of the index procedure and were largely driven by a difference in patients with rheumatic MS [cardiovascular death: 7 (10.6%) vs. 24 (3.2%), HRadj 4.80, 95% CI 1.98-11.6; disabling stroke: 4 (6.1%) vs. 16 (2.0%), HRadj 4.18, 95% CI 1.34-13.0]. CONCLUSION: Concomitant MS was documented in approximately one-fifth of patients undergoing TAVR for severe, symptomatic AS and associated with a three-fold increased risk of cardiovascular adverse events at 1 year. The difference emerged early and was largely driven by patients with rheumatic MS.