Post-exercise cardiac troponin (cTn) elevation is a recognised phenomenon which historically has been detected using standard sensitivity assays. More recently high-sensitivity assays have been developed and are now the gold standard for detection of cTn in the clinical setting. Although the assay's enhanced sensitivity confers benefits it has created new challenges for clinicians. By evaluating the change in cTn values over time, taking into account biological and analytical variation, the clinician is able to differentiate between a pathological and normal cTn value. As a result, serial cTn testing has become a fundamental component of the clinical assessment of chest pain patients and is included in the most recent definition for myocardial infarction and the latest guidelines for the management of acute coronary syndromes without persistent ST-segment elevation. A review of the cTn kinetics literature demonstrates a pattern of elevation and peak within the first 4 h after exercise dropping within 24 h. In contrast myocardial necrosis demonstrates a later cTn peak with a slower downslope occurring over several days. Understanding cTn kinetics facilitates clinician's decision making when presented with a chest pain patient post-exercise. Furthermore, it helps elucidate the underlying mechanism and establish the clinical significance of post-exercise cTn elevation, which in all other situations confers negative prognostic value. We recommend serial cTn testing in this scenario with a suggested algorithm included in this review.

CTnT increases above reference limits during a marathon. Magnitude of cTnT rise is related to exercise intensity relative to ventilatory threshold and V˙Omax, but not individuals' absolute cardiopulmonary fitness, training state or running history.

The current coronavirus disease 2019 (COVID-19) pandemic has put significant strain on all aspects of health care delivery, including palliative care services. Given the high mortality from this disease, particularly in the more vulnerable members of society, it is important to examine how best to deliver a high standard of end-of-life care during this crisis. This case series collected data from two acute hospitals examining the management of patients diagnosed with COVID-19 who subsequently died (n ¼ 36) and compared this with national and local end-of-life audit data for all other deaths. Our results demonstrated a shorter dying phase (38.25 hours vs. 74 hours) and higher rates of syringe driver use (72% vs. 33% in local audits), although with similar average mediation doses. Of note was the significant heterogeneity in the phenotype of deterioration in the dying phase, two distinct patterns emerged, with one group demonstrating severe illness with a short interval between symptom onset and death and another group presenting with a more protracted deterioration. This brief report suggests a spectrum of mode of dying. Overall, the cohort reflects previously described experiences, with increased frailty (median Clinical Frailty Scale score of 5) and extensive comorbidity burden. This brief report provides clinicians with a contemporaneous overview of our experience, knowledge, and pattern recognition when caring for people with COVID-19 and highlights the value of proactive identification of patients and risk of deterioration and palliation.

Background The COVID‐19 pandemic has been associated with an unprecedented number of critical care survivors. Their experiences through illness and recovery are likely to be complex, but little is known about how best to support them. This study aimed to explore experiences of illness and recovery from the perspective of survivors, their relatives and professionals involved in their care. Study design In‐depth qualitative interviews were conducted with three stakeholder groups during the first wave of the pandemic. A total of 23 participants (12 professionals, 6 survivors and 5 relatives) were recruited from 5 acute hospitals in England and interviewed by telephone or video call. Data analysis followed the principles of Reflexive Thematic Analysis. Findings Three themes were generated from their interview data: (1) Deteriorating fast—a downhill journey from symptom onset to critical care; (2) Facing a new virus in a hospital—a remote place; and (3) Returning home as a survivor, maintaining normality and recovering slowly. Conclusions Our findings highlight challenges in accessing care and communication between patients, hospital staff and relatives. Following hospital discharge, patients adopted a reframed ‘survivor identity’ to cope with their experience of illness and slow recovery process. The concept of survivorship in this patient group may be beneficial to promote and explore further. Relevance to clinical practice All efforts should be made to continue to improve communication between patients, relatives and health professionals during critical care admissions, particularly while hospital visits are restricted. Adapting to life after critical illness may be more challenging while health services are restricted by the impacts of the pandemic. It may be beneficial to promote the concept of survivorship, following admission to critical care due to severe COVID‐19.

Background As a sequela of the COVID-19 pandemic, a large cohort of critical illness survivors have had to recover in the context of ongoing societal restrictions. Objective We aimed to use smartwatches (Fitbit Charge 3; Fitbit LLC) to assess changes in the step counts and heart rates of critical care survivors following hospital admission with COVID-19, use these devices within a remote multidisciplinary team (MDT) setting to support patient recovery, and report on our experiences with this. Methods We conducted a prospective, multicenter observational trial in 8 UK critical care units. A total of 50 participants with moderate or severe lung injury resulting from confirmed COVID-19 were recruited at discharge from critical care and given a smartwatch (Fitbit Charge 3) between April and June 2020. The data collected included step counts and daily resting heart rates. A subgroup of the overall cohort at one site—the MDT site (n=19)—had their smartwatch data used to inform a regular MDT meeting. A patient feedback questionnaire and direct feedback from the MDT were used to report our experience. Participants who did not upload smartwatch data were excluded from analysis. Results Of the 50 participants recruited, 35 (70%) used and uploaded data from their smartwatch during the 1-year period. At the MDT site, 74% (14/19) of smartwatch users uploaded smartwatch data, whereas 68% (21/31) of smartwatch users at the control sites uploaded smartwatch data. For the overall cohort, we recorded an increase in mean step count from 4359 (SD 3488) steps per day in the first month following discharge to 7914 (SD 4146) steps per day at 1 year (P=.003). The mean resting heart rate decreased from 79 (SD 7) beats per minute in the first month to 69 (SD 4) beats per minute at 1 year following discharge (P<.001). The MDT subgroup’s mean step count increased more than that of the control group (176% increase vs 42% increase, respectively; +5474 steps vs +2181 steps, respectively; P=.04) over 1 year. Further, 71% (10/14) of smartwatch users at the MDT site and 48% (10/21) of those at the control sites strongly agreed that their Fitbit motivated them to recover, and 86% (12/14) and 48% (10/21), respectively, strongly agreed that they aimed to increase their activity levels over time. Conclusions This is the first study to use smartwatch data to report on the 1-year recovery of patients who survived a COVID-19 critical illness. This is also the first study to report on smartwatch use within a post–critical care MDT. Future work could explore the role of smartwatches as part of a randomized controlled trial to assess clinical and economic effectiveness. International Registered Report Identifier (IRRID) RR2-10.12968/ijtr.2020.0102

Background/Aims The COVID-19 pandemic has created the need for research on how to effectively rehabilitate patients who have been discharged from an intensive care unit. This study is a protocol for a mixed methods feasibility study addressing the research questions: 1) what are the needs of patients who have survived COVID-19? 2) is the use of technology feasible to support their recovery? Methods A multicentre, technology supported, rehabilitation intervention for survivors of critical illness caused by COVID-19 will be assessed. Survivors in the study population will be offered a smartwatch to monitor their activity levels and will have biopsychosocial outcome measures monitored at three time points: discharge from hospital, 2–3 months post discharge and 1 year post discharge. Semi-structured interviews will be conducted across eight hospital sites with survivors, their relatives and professionals to understand their recovery experiences. Conclusions Designed by frontline clinicians, this protocol outlines a feasibility study that will provide new knowledge on the process of recovery of critical illness caused by COVID-19.

Endurance exercise is an established cause of cardiac troponin (cTn) elevation, of further interest is whether this rise represents clinical significance. This study compared cTnT rise in three cohorts of marathon runners using a high-sensitivity assay; control runners, those with known heart disease and runners who collapsed at the finish line. Control runners (n = 126) and runners with heart disease (n = 12) were prospectively recruited with cTnT levels measured pre-race and at race completion.Collapsed runners (n = 15) were retrospectively recruited. A mixed model ANCOVA was used to compare the three groups. Pre-race median cTnT for the control group and heart disease groups was 3.9 ng/L (IQR 3.1 ng/L) and 4.1 ng/L (IQR 3.4 ng/L).Post-race values for the three groups were control 45.6 ng/L (IQR 42.5 ng/L), heart disease 41.2 ng/L (IQR 36.1 ng/L), and collapsed 41.9 ng/L (IQR 57.8 ng/L). Postrace cTnT and cTnT change were significantly correlated with pre-race cTnT within the control group (r = 0.38 and 0.30, P < 0.01). There was no difference in post-race cTnT (adjusted for pre-race cTnT) between the three groups. None of the runners reported symptoms suggestive of acute myocardial infarction on follow-up. These results demonstrate that marathon running is associated with an asymptomatic cTnT rise for all runners, and this rise is significantly correlated to baseline cTnT levels, in addition, marathon runners with pre-existing cardiac pathology or who collapse at the finish line do not exhibit an increased cTnT rise compared to healthy runners. K E Y W O R D Scardiac, Marathon, running, troponin

In the acute hospital setting the COVID-19 pandemic presents some unique challenges to acute patient care. These include accurate recognition of cases, confirmation of both testing requests and results, establishing patient acuity and alerting to deterioration. We report our experience introducing a digital COVID-19 assessment tool with an associated live dashboard at two acute NHS hospitals, enabling accurate hospital-level reporting alongside risk stratification.