Comorbidity Profiling in Rural and Urban Population of West Bengal, India: Report From a Community-Based Primary Healthcare System.

Introduction The burden of non-communicable diseases (NCDs) is fast changing across the world, especially in the context of rapid urbanization, adoption of Western lifestyles, and an aging multi-morbid population. Over the last three decades, India has undergone a significant demographic and socioeconomic transition. For effective targeting of health system resources and services, it is essential to understand how the prevalence of NCDs varies among population groups across India. We set out to understand the distribution of NCDs and co-morbidities in urban and rural West Bengal. Methods As part of a service improvement project, data was collected from four urban and four rural community-based clinics across West Bengal, India. The reason for visiting the healthcare center was recorded as the primary diagnosis and co-morbidities were recorded per the Elixhauser comorbidity scoring criteria. Associations between all the demographic variables and NCDs were studied using the Poisson regression model and multivariate analysis. Demographic profile, co-morbidities, and Elixhauser comorbidity index were expressed as frequency (%), mean (standard deviation, SD), or median (interquartile range, IQR) as appropriate. Results We obtained data from 1244 patients of which 886 (71%) were from urban areas and 358 (29%) were from rural areas. Patients were mostly female (61%) and had a mean (SD) age of 53 (11) years. There was a positive correlation between living in an urban residence and age, body mass index (BMI), hypertension, cardiovascular disease (CVD), and respiratory disease. There was a positive correlation between CVD and age, male sex, living in an urban residence, and hypertension but did not correlate positively with diabetes. BMI positively correlated with living in an urban residence, hypertension, diabetes, and musculoskeletal disorders. We observed a significantly higher prevalence of musculoskeletal (p=0.002) and psychological diseases (p<0.001) in the rural population, while the prevalence of hypertension (p<0.001) and respiratory diseases among the participants living in urban areas was higher (p<0.001). There was no statistically significant difference in the prevalence of diabetes between urban and rural areas (p=0.38). In the multivariable analyses, we observed that increased age, being overweight, and living in urban areas were associated with hypertension (prevalence ratio (PR): 1.40, 1.30, and 1.30, respectively; all p-values <0.05). An interaction between sex and living area was associated with a lower prevalence of musculoskeletal diseases (PR: 0.34; 95%CI: 0.18-0.66), i.e., musculoskeletal diseases were less prevalent in males living in urban areas (p=0.002). Conclusion There is a rise in multimorbidity with changing demographic patterns and a narrowing of the urban-rural gap in disease distribution. More investment is required in risk factor prevention, screening, and treatment, with greater accessibility of healthcare resources for those in rural areas. Further work needs to be done to study the trends and distribution of NCDs in West Bengal to inform healthcare policy.

High-Flow Nasal Cannula Oxygen Therapy in the Management of Respiratory Failure: A Review.

High-flow nasal cannula (HFNC) oxygen therapy is gaining traction globally as a treatment for respiratory failure. There are several physiological benefits, and there is a growing body of evidence showing improved quality of life and patient comfort with HFNC, both in acute and home settings. Due to the increased burden of long-term respiratory conditions such as chronic obstructive pulmonary disease (COPD) on healthcare systems worldwide, the role of ward-based and post-discharge interventions in the prevention of hospital readmissions is an area of increasing interest. In this narrative review, we outline the physiological effects of HFNC and assess its applications in both the hospital and home settings for acute and chronic respiratory failure. We also consider the evidence of non-invasive ventilation (NIV) versus HFNC in the hospital setting and the application of HFNC at home in stable hypercapnic respiratory failure to improve the quality of life and prevent readmissions. We also look at applications of HFNC in specific circumstances, such as the perioperative period, emergency department, and acute (mainly critical care) setting including in immunocompromised patients and palliative care.

Theophylline Toxicity: A Differential to Consider in Patients on Long-Term Theophylline Presenting With Nonspecific Symptoms.

Theophylline has been used for decades as a bronchodilator to treat asthma and chronic obstructive pulmonary disease (COPD). The precise mode of action is still uncertain. Since beta-2 agonists are at least as effective as theophylline as a bronchodilator while having fewer side effects, theophylline has become less popular in recent clinical practice as the first-line treatment in patients with airway obstruction due to its narrow therapeutic window, which necessitates frequent level monitoring, severe side effects that can be fatal, and interactions with other medications. Patients with a chronic theophylline overdose often present with nonspecific gastrointestinal symptoms, which can result in misdiagnosis for a variety of gastrointestinal conditions. Convulsions that may be fatal can occur as a result of a theophylline overdose. Therefore, it is important to manage individuals who have been taking theophylline for a long period and have nonspecific cardiac or gastrointestinal symptoms with a high index of suspicion for theophylline toxicity. We present a case of a COPD patient who had no regular theophylline level monitoring for two years. He presented with vague gastrointestinal symptoms for the past six months and was initially suspected of having gastrointestinal cancer due to weight loss caused by decreased oral intake due to nausea and vomiting. He was suspected of having theophylline toxicity because he was on long-term theophylline and did not have frequent theophylline level monitoring. His theophylline level was measured and found to be high at 28.9 mL/L (normal level, 15 mL/L). He was given conservative treatment, including intravenous fluid and electrolyte replacements, and close monitoring of his theophylline levels.

COVID-19 infodemic and health-related quality of life in patients with chronic respiratory diseases: A multicentre, observational study.

Background: The explosion of information, misinformation and disinformation (the "infodemic") related to the coronavirus disease 2019 (COVID-19) pandemic on digital and social media is reported to affect mental health and quality of life. However, reports assessing the COVID-19 infodemic on health-related quality of life (HRQL) in patients with chronic diseases are scarce. In this study, we investigated the associations between the infodemic and HRQL in uninfected individuals with pre-existing chronic respiratory diseases (CRDs) such as asthma, chronic obstructive pulmonary disease (COPD) and other CRDs. Methods: We conducted a multi-national, cross-sectional, observational study in Canada, India, New Zealand and the United Kingdom where we distributed a set of digitised questionnaires among 1018 participants with chronic respiratory diseases who were not infected with the SARS-CoV-2 virus at least three months prior to the study. We collected information about the infodemic such as news watching or social media use more than usual during the pandemic. HRQL was assessed using the short form of the chronic respiratory questionnaire (SF-CRQ). Demographic information, comorbidities, compliance, mental health, behavioural function, and social support were also recorded. We analysed the direct and indirect relationships between infodemic and HRQL using structural equation models (SEM). Results: Of all participants, 54% were females and had a mean (standard deviation (SD)) age of 53 (17) years. We found that higher infodemic was associated with worse emotional function (regression coefficient ß = -0.08; 95% confidence interval (CI) = -0.14 to -0.01), which means a one SD change of the higher infodemic latent variable was associated with a 0.08 SD change of emotional function level. The association between higher infodemic and worse emotional function was mediated by worse mental health and behavioural functions but is marginally ameliorated by improved social support. In stratification analysis, we found significant disease and country-wise variations in the associations between infodemic and SF-CRQ domain scores. Conclusions: These results provide new evidence that the COVID-19 infodemic significantly influences the HRQL in patients with CRDs through a complex interplay between mental health, behavioural function, and social support. This new dimension of research also opens avenues for further research on infodemic-related health effects in other chronic diseases.

Raoultella planticola Pneumonia: A Rare Causative Organism.

We present a case of Raoultella planticola (R. planticola) infection that resulted in community-acquired pneumonia in an immunocompetent patient with an eight-week history of productive cough. This gram-negative bacterium is typically found in the environment and has the potential to infect humans. Raoultella planticola infections in humans have been recorded in several case reports from throughout the world in recent years, usually affecting immunocompromised patients. Although R. planticola is sensitive to most antibiotic groups, recent studies have revealed an increase in the infrequent acquisition of resistance genes in R. planticola, such as carbapenem resistance, making this pathogen a potential emergent threat. Our patient acquired R. planticola pneumonia in the absence of any underlying risk factors, making this the first case in the UK of R. planticola causing community-acquired pneumonia in an immunocompetent person.

Long-Term Mortality following Acute Noninvasive Ventilation for Obesity-Related Respiratory Failure: A Retrospective Single-Centre Study.

Introduction: Determinants of long-term mortality following acute hypercapnic respiratory failure have been extensively studied in patients with chronic obstructive pulmonary disease. However, respiratory failure due to obesity has not been studied to the same extent. This retrospective survey aims to identify whether admission pH is associated with long-term mortality in patients requiring acute noninvasive ventilation (NIV) for obesity-related respiratory failure (ORRF). Methods: Records from April 2013 to March 2020 were accessed from a NIV quality database at an acute teaching hospital. Adults with hypercapnic ORRF requiring acute NIV were included. pH data were grouped by threshold (pH≤ and >7.25) and correlated with time from presentation to death; multivariable analysis was performed using Cox proportional hazards. Results: A total of 277 acute NIV episodes were included. Two-year mortality was similar for patients in both pH categories. Univariable analysis identified pH ≤ 7.25 to increase risk of two-year mortality by 43%. However, multivariable analysis identified that pH was not a significant determinant of long-term mortality, although male sex, older age, and higher admission pCO2 increased the risk of death at two years by 76%, 3% per year of age, and 16% per 1 kPa of pCO2 increase, respectively. Conclusion: Severity of hypercapnia on admission, male sex, and older age are associated with worse two-year mortality in patients requiring acute NIV for ORRF. There is scope for further analyses including investigating the role of domiciliary NIV in ORRF patients.

Less Social Deprivation Is Associated With Better Health-Related Quality of Life in Asthma and Is Mediated by Less Anxiety and Better Sleep Quality.

BACKGROUND: Previous studies on health-related quality of life (HRQoL) in asthma have mainly focused on clinical and environmental determinants. Little is known about the role of social determinants on HRQoL in asthma. OBJECTIVES: We aimed to investigate the association between social deprivation and HRQoL in asthma. METHODS: A total of 691 adult asthmatics from Canada, India, New Zealand, and the United Kingdom were administered a digital questionnaire containing demographic information and questions about social and psychological attributes, sleep disturbances, and alcohol abuse. HRQoL was measured using the Short Form of the Chronic Respiratory Questionnaire (SF-CRQ). We analyzed the direct and indirect relationships between social deprivation and HRQoL using structural equation models with social deprivation as a latent variable. We tested for mediation via anxiety, depression, sleep disturbances, and alcohol abuse. RESULTS: We found that less social deprivation (latent variable) was directly associated with better SF-CRQ domain scores such as dyspnea (regression coefficient ß: 0.33; 95% confidence interval [CI]: 0.07 to 0.58), fatigue (ß: 0.39; 95% CI: 0.14 to 0.64), and emotional function (ß: 0.37; 95% CI: 0.11 to 0.62), but with the worse mastery score (ß: -0.29; 95% CI: -0.55 to -0.03); however, those associations varied across participating countries. We also observed that among all individual social deprivation indicators, education, companionship, emotional support, instrumental support, and social isolation were directly associated with HRQoL, and the relationship between social deprivation and HRQoL was mediated through anxiety and sleep disturbances. CONCLUSIONS: Our results demonstrated that less social deprivation was directly, and indirectly through less anxiety and better sleep quality, associated with better HRQoL in asthma.

Non-invasive localization of post-infarct ventricular tachycardia exit sites to guide ablation planning: a computational deep learning platform utilizing the 12-lead electrocardiogram and intracardiac electrograms from implanted devices.

AIMS: Existing strategies that identify post-infarct ventricular tachycardia (VT) ablation target either employ invasive electrophysiological (EP) mapping or non-invasive modalities utilizing the electrocardiogram (ECG). Their success relies on localizing sites critical to the maintenance of the clinical arrhythmia, not always recorded on the 12-lead ECG. Targeting the clinical VT by utilizing electrograms (EGM) recordings stored in implanted devices may aid ablation planning, enhancing safety and speed and potentially reducing the need of VT induction. In this context, we aim to develop a non-invasive computational-deep learning (DL) platform to localize VT exit sites from surface ECGs and implanted device intracardiac EGMs. METHODS AND RESULTS: A library of ECGs and EGMs from simulated paced beats and representative post-infarct VTs was generated across five torso models. Traces were used to train DL algorithms to localize VT sites of earliest systolic activation; first tested on simulated data and then on a clinically induced VT to show applicability of our platform in clinical settings. Localization performance was estimated via localization errors (LEs) against known VT exit sites from simulations or clinical ablation targets. Surface ECGs successfully localized post-infarct VTs from simulated data with mean LE = 9.61 ± 2.61 mm across torsos. VT localization was successfully achieved from implanted device intracardiac EGMs with mean LE = 13.10 ± 2.36 mm. Finally, the clinically induced VT localization was in agreement with the clinical ablation volume. CONCLUSION: The proposed framework may be utilized for direct localization of post-infarct VTs from surface ECGs and/or implanted device EGMs, or in conjunction with efficient, patient-specific modelling, enhancing safety and speed of ablation planning.

Media power in digital Asia: Super apps and megacorps.

Tracing global shifts in ownership and conglomeration in the media and technology sectors, this introduction analyzes the emergence of the 'megacorp' and 'super app' as distinct forms and sites of media power. With a focus on Asia, we argue that the pairing of megacorps and super apps is driving the emergence of powerful digital companies that shape social, cultural, and political dynamics worldwide. Through analyses of companies including Reliance, SoftBank, Tencent, Alibaba, and Transsion, this special issue calls for a renewed engagement with theories of monopoly capital via the megacorp, and accounts of consumer and citizen experiences of this monopoly via a quotidian touch point, the super app. In conversation with scholarship on conglomerates, monopolies, and platforms as key institutional forms of media power, we show that media power in this digital conjuncture operates as much through national and regional differences as through the imperative to achieve a global scale.

Active Tracking-based cardiac triggering for MR-thermometry during radiofrequency ablation therapy in the left ventricle.

Cardiac MR thermometry shows promise for real-time guidance of radiofrequency ablation of cardiac arrhythmias. This technique uses ECG triggering, which can be unreliable in this situation. A prospective cardiac triggering method was developed for MR thermometry using the active tracking (AT) signal measured from catheter microcoils. In the proposed AT-based cardiac triggering (AT-trig) sequence, AT modules were repeatedly acquired to measure the catheter motion until a cardiac trigger was identified to start cardiac MR thermometry using single-shot echo-planar imaging. The AT signal was bandpass filtered to extract the motion induced by the beating heart, and cardiac triggers were defined as the extremum (peak or valley) of the filtered AT signal. AT-trig was evaluated in a beating heart phantom and in vivo in the left ventricle of a swine during temperature stability experiments (6 locations) and during one ablation. Stability was defined as the standard deviation over time. In the phantom, AT-trig enabled triggering of MR thermometry and resulted in higher temperature stability than an untriggered sequence. In all in vivo experiments, AT-trig intervals matched ECG-derived RR intervals. Mis-triggers were observed in 1/12 AT-trig stability experiments. Comparable stability of MR thermometry was achieved using peak AT-trig (1.0 ± 0.4°C), valley AT-trig (1.1 ± 0.5°C), and ECG triggering (0.9 ± 0.4°C). These experiments show that continuously acquired AT signal for prospective cardiac triggering is feasible. MR thermometry with AT-trig leads to comparable temperature stability as with conventional ECG triggering. AT-trig could serve as an alternative cardiac triggering strategy in situations where ECG triggering is not effective.

Provocation and localization of atrial ectopy in patients with atrial septal defects.

BACKGROUND: Atrial fibrillation (AF) is associated with atrial septal defects (ASDs), but the mechanism of arrhythmia in these patients is poorly understood. We hypothesised that right-sided atrial ectopy may predominate in this cohort. Here, we aimed to localise the origin of spontaneous and provoked atrial ectopy in ASD patients. METHODS: Following invasive calibration of P-wave axes, 24-h Holter monitoring was used to determine the chamber of origin of spontaneous atrial ectopy. Simultaneous electrogram recording from multiple intra-cardiac catheters was used to determine the chamber of origin of isoprenaline-provoked ectopy. Comparison was made to a group of non-congenital heart disease AF patients. RESULTS: Amongst ASD patients, a right-sided origin for spontaneous atrial ectopy was significantly more prevalent than a left-sided origin (24/30 patients with right-sided ectopy vs. 14/30 with left-sided ectopy, P = 0.015). Amongst AF patients, there was no difference in the prevalence of spontaneous right vs. left-sided ectopy. For isoprenaline-provoked ectopy, there was no significant difference in the proportions of patients with right-sided or left-sided ectopy in either group. CONCLUSIONS: When spontaneous atrial ectopy occurs in ASD patients, it is significantly more prevalent from a right-sided than left-sided origin. Isoprenaline infusion did not reveal the predilection for right-sided ectopy during electrophysiology study.

The benefits of a home non-invasive ventilation retrieval service: Improved effectiveness and environmental sustainability in challenging times.

In the last 6 months, home non-invasive ventilation (NIV) services have faced several unanticipated challenges to their effectiveness and delivery as the result of a 'perfect storm' of the COVID-19 pandemic demands. We developed and delivered an innovative follow-up service, to support home NIV delivery, and improve cost-effectiveness and sustainability during COVID-19. Between Feb-2019 and Nov-2020, 92 post-acute patients were issued with home NIV; 25 (27%) out of the 92 patients had unused NIV machines successfully retrieved. The median (IQR) days of home NIV usage were 207 (98) for patients who had their machines returned. All the unused NIV machines retrieved were within the 5-year working life guaranteed by the manufacturer and were all redeployed after appropriate reconditioning and infection control measures. Without the home-visiting and recycling pilot, we would have relied on patients and families to return the unused machines. Given the expected disruption to NIV machine supply for at least the foreseeable 12-18 months, we feel it is important to get this important message out to other home NIV services urgently. Wider implementation of this novel approach could increase the availability of this vital resource and help meet the current demand on home NIV services.

Home Non-Invasive Ventilation in COPD: A Global Systematic Review.

Background: Uncertainty remains around the benefit of home non-invasive ventilation (NIV) for stable chronic obstructive pulmonary disease (COPD) patients and those with a recent exacerbation (post-hospital). The aim of this systematic review was to: (1) update the evidence base with studies published in any language, including Chinese language studies not indexed in standard medical databases, and (2) explore the impact of additional studies on the evidence base. Methods: Standard systematic review methodology was used for identifying and appraising studies. Randomized controlled trials (RCTs) and non-randomized studies reporting mortality, hospitalizations, exacerbations, quality of life, adverse events, or adherence were included. Random effects meta-analysis was undertaken for mortality and hospitalizations, with studies sub-grouped by population and study design. Sensitivity analysis was performed to explore the effect of including studies from Western and non-Western countries. Results: A total of 103 studies were included, substantially more than in previous reviews. There was no significant effect on mortality for the stable population. There was a benefit from NIV for the post-hospital population based on non-randomized studies, or RCTs from non-Western countries. There was a small but significant reduction in hospital admissions (1-2/year) with NIV across all sub-groups, and a variable reduction in duration of stay with greater reductions in studies from China. Conclusions: The evidence base on home NIV is considerably larger than previously presented. While NIV may reduce hospital admissions and improve quality of life, there is still little evidence of a reduction in mortality, regardless of country. Individual participant data analysis may clarify which patients would benefit most from NIV.

The Effect of Telemonitoring (TM) on Improving Adherence with Continuous Positive Airway Pressure (CPAP) in Obstructive Sleep Apnoea (OSA): A Service Improvement Project (SIP).

The benefits of CPAP demonstrated in clinical trials are difficult to deliver in real life due to the lack of adherence. We analysed the effect of a Telemonitoring (TM)-related intervention on adherence as part of a Service Improvement Project (SIP) analysed as a retrospective cohort study. The 'historical control' (HC) cohort (followed up in conventional clinics) included all patients who commenced on CPAP between 1 February and 30 April 2019 (n = 142). The 'telemonitoring' (TM) cohort included all patients who commenced on CPAP between 1 May and 31 July 2019 (n = 166). Adherence was checked at 30 days (baseline) and 73 days for both cohorts. Wilcoxon-Rank test was used for statistical analysis (results reported as mean ± SEM). Both cohorts had similar adherence at the 30-day baseline, compared to a significantly lower adherence in the HC-cohort at 73 days (55.7 ± 3.0 vs. 51.8 ± 3.2% of days ≥ 4 h: p = 0.0072, average usage 255 ± 12.8 vs. 236 ± 13.7 min: p = 0.0003). There was a significantly higher adherence in the TM-cohort at 73 days (50.8 ± 2.5 vs. 56.1 ± 2.9% of days ≥ 4 h: p = 0.0075; average usage 234 ± 10.4 vs. 252 ± 12.1 min: p = 0.0456). Telemonitoring-feedback is effective at improving adherence with CPAP, suggesting its potential beneficial role in the community setting, particularly in the post-COVID reality of increased remote consultations.

CArdiac MagnEtic resonance assessment of bi-Atrial fibrosis in secundum atrial septal defects patients: CAMERA-ASD study.

AIMS: Atrial septal defects (ASD) are associated with atrial arrhythmias, but the arrhythmia substrate in these patients is poorly defined. We hypothesized that bi-atrial fibrosis is present and that right atrial fibrosis is associated with atrial arrhythmias in ASD patients. We aimed to evaluate the extent of bi-atrial fibrosis in ASD patients and to investigate the relationships between bi-atrial fibrosis, atrial arrhythmias, shunt fraction, and age. METHODS AND RESULTS: Patients with uncorrected secundum ASDs (n = 36; 50.4 ± 13.6 years) underwent cardiac magnetic resonance imaging with atrial late gadolinium enhancement. Comparison was made to non-congenital heart disease patients (n = 36; 60.3 ± 10.5 years) with paroxysmal atrial fibrillation (AF). Cardiac magnetic resonance parameters associated with atrial arrhythmias were identified and the relationship between bi-atrial structure, age, and shunt fraction studied. Bi-atrial fibrosis burden was greater in ASD patients than paroxysmal AF patients (20.7 ± 14% vs. 10.1 ± 8.6% and 14.8 ± 8.5% vs. 8.6 ± 6.1% for right and left atria respectively, P = 0.001 for both). In ASD patients, right atrial fibrosis burden was greater in those with than without atrial arrhythmias (33.4 ± 18.7% vs. 16.8 ± 10.3%, P = 0.034). On receiver operating characteristic analysis, a right atrial fibrosis burden of 32% had a 92% specificity and 71% sensitivity for predicting the presence of atrial arrhythmias. Neither age nor shunt fraction was associated with bi-atrial fibrosis burden. CONCLUSION: Bi-atrial fibrosis burden is greater in ASD patients than non-congenital heart disease patients with paroxysmal AF. Right atrial fibrosis is associated with the presence of atrial arrhythmias in ASD patients. These findings highlight the importance of right atrial fibrosis to atrial arrhythmogenesis in ASD patients.

Late Gadolinium Enhancement Cardiovascular Magnetic Resonance Assessment of Substrate for Ventricular Tachycardia With Hemodynamic Compromise.

Background: The majority of data regarding tissue substrate for post myocardial infarction (MI) VT has been collected during hemodynamically tolerated VT, which may be distinct from the substrate responsible for VT with hemodynamic compromise (VT-HC). This study aimed to characterize tissue at diastolic locations of VT-HC in a porcine model. Methods: Late Gadolinium Enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging was performed in eight pigs with healed antero-septal infarcts. Seven pigs underwent electrophysiology study with venous arterial-extra corporeal membrane oxygenation (VA-ECMO) support. Tissue thickness, scar and heterogeneous tissue (HT) transmurality were calculated at the location of the diastolic electrograms of mapped VT-HC. Results: Diastolic locations had median scar transmurality of 33.1% and a median HT transmurality 7.6%. Diastolic activation was found within areas of non-transmural scar in 80.1% of cases. Tissue activated during the diastolic component of VT circuits was thinner than healthy tissue (median thickness: 5.5 mm vs. 8.2 mm healthy tissue, p < 0.0001) and closer to HT (median distance diastolic tissue: 2.8 mm vs. 11.4 mm healthy tissue, p < 0.0001). Non-scarred regions with diastolic activation were closer to steep gradients in thickness than non-scarred locations with normal EGMs (diastolic locations distance = 1.19 mm vs. 9.67 mm for non-diastolic locations, p < 0.0001). Sites activated late in diastole were closest to steep gradients in tissue thickness. Conclusions: Non-transmural scar, mildly decreased tissue thickness, and steep gradients in tissue thickness represent the structural characteristics of the diastolic component of reentrant circuits in VT-HC in this porcine model and could form the basis for imaging criteria to define ablation targets in future trials.

Secondary Stroke Prevention Following Embolic Stroke of Unknown Source in the Absence of Documented Atrial Fibrillation: A Clinical Review.

Approximately one-third of ischemic strokes are classified as cryptogenic strokes. The risk of stroke recurrence in these patients is significantly elevated with up to one-third of patients with cryptogenic stroke experiencing a further stroke within 10 years. While anticoagulation is the mainstay of treatment for secondary stroke prevention in the context of documented atrial fibrillation (AF), it is estimated that up to 25% of patients with cryptogenic stroke have undiagnosed AF. Furthermore, the historical acceptance of a causal relationship between AF and stroke has recently come under scrutiny, with evidence to suggest that embolic stroke risk may be elevated even in the absence of documented atrial fibrillation attributable to the presence of electrical and structural changes constituting an atrial cardiomyopathy. More recently, the term embolic stroke of unknown source has garnered increasing interest as a subset of patients with cryptogenic stroke in whom a minimum set of diagnostic investigations has been performed, and a nonlacunar infarct highly suspicious of embolic etiology is suspected but in the absence of an identifiable secondary cause of stroke. The ongoing ARCADIA (Atrial Cardiopathy and Antithrombotic Drugs in Prevention After Cryptogenic Stroke) randomized trial and ATTICUS (Apixiban for Treatment of Embolic Stroke of Undetermined Source) study seek to further define this novel term. This review summarizes the relationship between AF, embolic stroke, and atrial cardiomyopathy and provides an overview of the clinical relevance of cardiac imaging, electrocardiographic, and serum biomarkers in the assessment of AF and secondary stroke risk. The implications of these findings on therapeutic considerations is considered and gaps in the literature identified as areas for future study in risk stratifying this cohort of patients.