When Rhythm Changes Cause the Blues: New-Onset Atrial Fibrillation during Sepsis

Unexpected sepsis due to Group A beta haemolytic Streptococcus following total thyroidectomy

Thyroidectomy is a clean surgery, with the presentation of postoperative infections being uncommon and an exceedingly rare incidence of postoperative sepsis.A female patient in her early 80s became acutely unwell following total thyroidectomy within the immediate postoperative period, with features suggestive of sepsis. She developed new-onset atrial fibrillation (AF), and her care was escalated to the intensive treatment unit (ITU) on the same day postoperatively. While in the ITU, she deteriorated with multiorgan failure (MOF). There was no evidence of a surgical site infection (SSI).Beta haemolytic lancefield Group A Streptococcus (GAS) was isolated from positive blood cultures, confirming the diagnosis of streptococcal toxic shock syndrome (TSS). She was treated with targeted antibiotics and intravenous immunoglobulin (IG) and received supportive care for MOF.In our case, sepsis developed in the immediate postoperative period of total thyroidectomy. A high index of suspicion and prompt treatment are required to minimise the risks of morbidity and mortality.

Comparison of rhythm and rate control medications for new-onset atrial fibrillation in septic patients: MIMIC-IV database analysis

BACKGROUND

The optimal management strategy for new-onset atrial fibrillation (NOAF) in patients with sepsis remains unclear. This study aimed to investigate and compare the associations of rhythm control medications versus rate control medications with mortality outcomes in septic patients with NOAF.

METHODS

This propensity score-matched cohort study utilized data from the Medical Information Mart in Intensive Care-IV database. Adult septic patients with NOAF were categorized into two groups based on initial medications (rhythm or rate control). The primary outcome was 28-day mortality, with secondary outcomes including intensive care unit(ICU),1-year mortality.

RESULTS

A total of 586 patients were included in the prematched cohort, with 277 patients remaining after propensity score matching. In the matched cohort, the primary outcome of 28-day mortality rate was 49.7% (85/171) in the rate control group and 46.2% (49/106) in the rhythm control group, with no significant difference between the groups (HR 0.97; 95% CI 0.68-1.37,P = 0.849). Secondary outcomes showed that rhythm control medications were not associated with increased ICU mortality (HR 1.03, 95% CI 0.60-1.78, P = 0.906) or 1-year mortality (HR 0.84, 95% CI 0.61-1.16, P = 0.299).However, the rhythm control group had higher successful cardioversion rates compared to the rate control group at 6 h (68.9% vs. 49.1%, P = 0.001), 12 h (71.1% vs. 52.4%, P = 0.002), and 24 h (72.7% vs. 53.2%, P = 0.002).

CONCLUSIONS

In septic patients with NOAF, rhythm control and rate control medications showed no difference in 28-day, ICU, or 1-year mortality.However, rhythm control may provide transient hemodynamic stabilization through rapid cardioversion, potentially beneficial during acute critical illness.

[Vasoactive agents in septic shock-individualized strategies]

Hemodynamic stabilization and preservation of organ perfusion are central elements in the management of septic shock. This is achieved by fluid resuscitation and by administration of vasoactive agents. Current guidelines recommend norepinephrine as the first-line vasoactive substance. In cases of high norepinephrine requirements the addition of nonadrenergic vasopressors is recommended. Furthermore, evidence suggests that early use of complementary vasoactive substances may provide additional benefits. Such a regimen, in terms of a broad-spectrum vasopressor approach, appears physiologically plausible. Post hoc analyses of studies investigating vasopressin or angiotensin II also suggest that specific subphenotypes may particularly benefit from individual vasoactive agents. Adjunctive therapy with hydrocortisone and fludrocortisone can improve vasopressor responsiveness and reduce mortality. In cases of cardiac dysfunction, a trial with dobutamine or a switch from norepinephrine to epinephrine is recommended. To enhance inodilator effects, milrinone or levosimendan may represent additional therapeutic options for certain patients. Although short-acting beta-blockers are not part of the standard treatment for septic shock, they may, in selected cases, contribute to hemodynamic improvement in patients with inadequately high sinus tachycardia or atrial tachyarrhythmias. Based on pathophysiological considerations and the currently available evidence, targeted use of specific vasoactive substances in defined subphenotypes may be justified. An initial broad-spectrum vasopressor strategy incorporating biomarkers such as renin and patient-specific characteristics followed by a focused de-escalation approach could represent a promising concept. However, the effectiveness of these strategies requires further investigation in randomized controlled trials.

New-Onset, But Not Chronic Atrial Fibrillation, Is a Significant Factor Contributing to Mortality Among Patients with Severe COVID-19

BACKGROUND Atrial fibrillation (AF) is a common arrhythmia in the general population and the most frequently presented arrhythmia in the intensive care unit. We investigated the effects of AF on the outcomes of critical COVID-19 patients, especially focusing on differences between chronic (CAF) and new-onset AF (NOAF) during critical disease. MATERIAL AND METHODS In this case-control study, we investigated the association of CAF and NOAF as an exposure, with in-hospital mortality as an outcome. We identified 2 patient groups, NOAF and CAF, which were compared with controls (all other hospitalized patients with critical COVID-19 pneumonia). No specific selection or matching was performed. The chi-square test was used for categorical variables; t test and Mann-Whitney U tests were used for continuous variables, depending on distribution. P<0.05 was considered significant. RESULTS In-hospital mortality was significantly higher in the NOAF group, while in the CAF group, it was similar to that of the control group. The NOAF group had significantly higher markers of inflammation and more severe acute respiratory distress syndrome (ARDS), measured with computed tomography. NOAF was strongly associated with in-hospital death, with OR 6.392 (95% CI, 2.758-14.815), P<0.000. In comparison, the CAF group was older and had more cardiovascular comorbidities, with similar markers of inflammation and severity of ARDS as the control group. CONCLUSIONS NOAF in COVID-19 was linked with significant risk of death, being a sign of extreme cardiac, pulmonary, and metabolic instability. NOAF should be considered as an important marker of instability and predictor of poor outcomes among patients with COVID-19.

Beyond the Beat: A Multifaceted Review of Atrial Fibrillation in Sepsis: Risk Factors, Management Strategies, and Economic Impact

Atrial fibrillation (AF) is a common arrhythmia in critically ill patients. The objective of this narrative review is to evaluate the characteristics of patients who develop new-onset atrial fibrillation (NOAF) because of sepsis, current management of NOAF in sepsis patients, special consideration in different populations that developed NOAF, health economic and quality of life of patients. We conducted a literature search on PubMed to find research related to NOAF, sepsis and critical illness. Nineteen studies were analyzed for risk factors and outcomes. The incidence rate ranges from 0.53% to 43.9% among these studies. There were numerous risk factors that had been reported from these articles. The most reported risk factors included advanced age, male sex, White race, and cardiovascular comorbidities. The management of septic patients is significantly challenging because of the unfavorable cardiovascular consequences and thromboembolic hazards associated with NOAF. There are comprehensive guidelines available for managing AF, but the effectiveness and safety of therapies in patients with sepsis are still uncertain. Various approaches for managing newly diagnosed AF have been explored. Sinus rhythm can be restored through either pharmacological or non-pharmacological intervention or combination of both. In addition, thromboembolism is a complication that can occur in patients with AF and can have a negative impact on the prognosis of sepsis patients. The use of anticoagulation to prevent stroke after NOAF in sepsis patients is still controversial. Extensive prospective investigations are required to have a deeper understanding of the necessity for anticoagulation following NOAF in sepsis. Beside the treatment of NOAF, early detection of NOAF in sepsis plays a critical role. The prompt initiation of rhythm control medication following a clinical diagnosis of AF can enhance cardiovascular outcomes and reduce mortality in patients with AF and cardiovascular risk factors. Additionally, NOAF in the intensive care unit can prolong hospital stays, increasing hospitalization costs and burdening the hospital. Therefore, preventing and managing NOAF effectively not only benefit the patients but also the hospital in financial aspect. Lastly, to address the existing gaps in knowledge, future research should focus on developing machine learning models that can accurately anticipate risks, establish long-term follow-up protocols, and create complete monitoring systems. The focus is on early intervention and personalized approaches to improve outcomes and quality of life.

Cardiac Troponin I and Electrocardiographic Evaluation in Hospitalized Cats with Systemic Inflammatory Response Syndrome

Several studies conducted on humans demonstrate the increase in cardiac troponins and the onset of arrhythmias in the course of systemic inflammatory response syndrome (SIRS). The aim of the current study was to assess the blood concentration of cardiac troponin I (cTnI) and electrocardiographic findings in SIRS-affected cats. Seventeen shorthair cats hospitalized with SIRS were enrolled (Group 1). SIRS diagnosis was performed based on the detection of at least two of the four criteria such as abnormal body temperature, abnormal heart rate (i.e., tachycardia or bradycardia), abnormal respiratory rate (i.e., tachypnea or bradypnea), and alterations of white blood cell number (i.e., leukocytes or band neutrophils). Ten cats screened for elective surgery such as neutering or dental procedures were evaluated as a control population (Group 2). They were considered healthy based on history, physical examination, hematological and biochemical profile, urinalysis, coprological exam, thyroxine assay, blood pressure measurement, and echocardiography. A physical examination, complete blood cell count, biochemistry test (including an electrolyte panel), electrocardiographic examination, and cTnI assay were carried out in each cat enrolled. Traumatic events, gastrointestinal, neoplastic, respiratory, and neurological disorders were identified as causes of SIRS in Group 1. In Group 1, a significantly higher concentration of cTnI than that in Group 2 was recorded (p = 0.004). In 37.5% of cats with SIRS, ventricular premature complexes occurring in couplets with multiform configuration were detected. Similarly, to humans, data herein reported would indicate possible cardiac damage present in cats with SIRS diagnosis.

Prevalence of new-onset atrial fibrillation in hospitalized patients with community-acquired pneumonia: a systematic review and meta-analysis

Community-acquired pneumonia (CAP) is a common lower respiratory tract infection, often complicated by cardiovascular events, including cardiac arrhythmias. New-onset atrial fibrillation (newAF) has been associated with increased mortality in CAP patients, especially in those critically ill; however, limited data on the prevalence of newAF in patients with CAP are available. We aim to estimate the pooled prevalence of newAF and its impact on adverse outcomes in patients with CAP, through a systematic review and meta-analysis. MEDLINE and EMBASE were systematically searched from inception to 27 January 2022. All studies reporting the prevalence of newAF in CAP patients were included and all-cause mortality was extracted when available. The pooled prevalence of newAF, 95% Confidence Intervals (CI), and 95% Prediction Intervals (PI) were computed. The inconsistency index (I2) was calculated to measure heterogeneity. Subgroup analyses were also performed. A protocol for this study was registered on PROSPERO (CRD42022307422). Among 7,655 records retrieved, 10 studies were included, with a total of 280,589 CAP patients. Pooled prevalence of newAF in CAP patients was 7.6% (95% CI 6.4-9.0%, 95% PI 4.3-13.1%, I2 = 95%). Subgroup analyses showed no significant differences according to geographical location or study design. Patients with newAF had a higher risk of mortality among the studies included in the systematic review. NewAF is a common complication, occurring in 7.6% of CAP patients, with prediction intervals suggesting an even higher burden. CAP patients who develop newAF during hospitalization may be at higher risk of mortality in both short- and long-term follow-up.

Electrocardiographic Findings and Cardiac Troponin I Assay in Dogs with SIRS Diagnosis

Several studies performed in humans have demonstrated that the onset of systemic inflammatory response syndrome (SIRS) represents a high risk condition to develop myocardial damage and arrhythmias. Therefore, we also hypothesized cardiac involment for dogs affected by SIRS. To assess this hypothesis, 24 dogs with a diagnosis of SIRS (13 entire males, 7 entire females, and 4 spayed females) with an age ranging from 4 to 11 years (mean 5.6 years) and an average weight of 24 kg (range from 5 to 47 kg) were enrolled. The dogs were divided into two groups according to their prognosis: Survivors (G1) and not survivors (G2), composed by 13 and 11 dogs, respectively. Moreover, healthy dogs were included as the control group (CTR). All the dogs with a history of cardiac or renal disease were excluded. At the inclusion, each patient underwent a physical examination and a complete cell count, and a biochemistry panel (including electrolyte profile) was performed; moreover, the blood cardiac Troponin I (cTnI) was measured. For each clinical variable indicative of SIRS, a score between 0 (absence) and 1 (presence) was applied. Furthermore, an electrocardiographic examination was recorded. Seventeen out of 24 (70.8%) dogs with SIRS showed arrhythmias, of which n. 6 belonged to the G1, while n. 11 belonged to the G2. Most represented findings were sinus tachycardia (7/17; 41.1%), followed by monomorphic premature ventricular beats (6/17; 35.3%), less common were first-degree atrioventricular block (2/17; 11.7%) and sinus bradycardia 1/17; 5.8%). Notably, in G1 dogs, only sinus tachycardia and premature ventricular beats were observed. G2 dogs presented a number of total and banded leukocytes significantly higher than those of G1 (p = 0.002 and 0.049), in the same manner, the clinical score suggestive of SIRS (3 vs. 2.1) was significantly higher in G2 than in G1 dogs (p = 0.01). Moreover, a significantly higher value of cTnI was observed in the G2 group compared to the G1 group (p = 0.006). Data presented here suggested a cardiac involvement in dogs with SIRS, analogously to humans, that may significantly influence the patient's prognosis.

Prevalence of New-Onset Atrial Fibrillation and Associated Outcomes in Patients with Sepsis: A Systematic Review and Meta-Analysis

Background: New-onset atrial fibrillation (NOAF) is a common complication in patients with sepsis, although its prevalence and impact on outcomes are still unclear. We aim to provide a systematic review and meta-analysis on the prevalence of NOAF in patients with sepsis, and its impact on in-hospital mortality and intensive care unit (ICU) mortality. Methods: PubMed and EMBASE were systematically searched on 26 December 2021. Studies reporting on the prevalence of NOAF and/or its impact on in-hospital mortality or ICU mortality in patients with sepsis or septic shock were included. The pooled prevalence and 95% confidence intervals (CI) were calculated, as well as the risk ratios (RR), 95%CI and 95% prediction intervals (PI) for outcomes. Subgroup analyses and meta-regressions were performed to account for heterogeneity. Results: Among 4988 records retrieved from the literature search, 22 articles were included. Across 207,847 patients with sepsis, NOAF was found in 13.5% (95%CI: 8.9–20.1%), with high heterogeneity between studies; significant subgroup differences were observed, according to the geographical location, study design and sample size of the included studies. A multivariable meta-regression model showed that sample size and geographical location account for most of the heterogeneity. NOAF patients showed an increased risk of both in-hospital mortality (RR: 1.69, 95%CI: 1.47–1.96, 95%PI: 1.15–2.50) and ICU mortality (RR: 2.12, 95%CI: 1.86–2.43, 95%PI: 1.71–2.63), with moderate to no heterogeneity between the included studies. Conclusions: NOAF is a common complication during sepsis, being present in one out of seven individuals. Patients with NOAF are at a higher risk of adverse events during sepsis, and may need specific therapeutical interventions.

In-Hospital Mortality Among Critically Ill Patients With Atrial Fibrillation (AF) Versus Patients Without AF

Introduction

Atrial fibrillation (AF) is one of the most frequent arrhythmias observed in the intensive care unit (ICU). The present study assessed AF as an independent risk factor for mortality among patients in the ICU setting.

Methodology

A prospective cohort study was conducted at the medical ICU in a tertiary academic medical center from September 2020 to January 2021. All critically ill patients, irrespective of gender, who were admitted for at least two days in the ICU were eligible to partake in the study. Individuals in the cardiovascular surgical ICU and the trauma ICU were not eligible. Demographics, clinical history, the occurrence of AF, fluid input and output, echocardiography, drug history, and hospital mortality were recorded during the first week of admission. Patients were divided into two groups.

Results

Patients with AF had significantly higher in-hospital mortality, 27 (73%), and longer hospital stays (11.61 ± 7.01) as compared to patients who did not suffer from AF (p<0.0001). The mean length of stay in ICU was 10.32 ± 5.92 and the duration of mechanical ventilation was 7.05 ± 6.16 days in the AF group which was significantly higher than patients who did not have AF (p<0.0001). No significant difference was found in mortality rate between new-onset and recurrent AF among the patients; albeit the latter was higher (60% vs 81.8%, p=0.142).

Conclusion

The present study indicated that AF was a predictor of mortality hence, associated with poor patient prognosis. The occurrence of AF was associated with high in-hospital mortality and longer hospital stay. Further large-scale studies should be conducted to explore other socio-demographic and clinical risk factors.

Prevalence and Impact of Atrial Fibrillation in Hospitalized Patients with COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

In patients with COVID-19, cardiovascular complications are common and associated with poor prognosis. Among these, an association between atrial fibrillation (AF) and COVID-19 has been described; however, the extent of this relationship is unclear. The aim of this study is to investigate the epidemiology of AF in COVID-19 patients and its impact on all-cause mortality.

METHODS

A systematic review and meta-analysis were performed and reported according to PRISMA guidelines, and a protocol for this study was registered on PROSPERO (CRD42021227950). PubMed and EMBASE were systematically searched for relevant studies. A random-effects model was used to estimate pooled odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Overall, 31 studies were included in the analysis, with a total number of 187,716 COVID-19 patients. The prevalence of AF was found to be as high as 8% of patients with COVID-19 (95% CI: 6.3-10.2%, 95% prediction intervals (PI): 2.0-27.1%), with a high degree of heterogeneity between studies; a multiple meta-regression model including geographical location, age, hypertension, and diabetes showed that these factors accounted for more than a third of the heterogeneity. AF COVID-19 patients were less likely to be female but more likely older, hypertensive, and with a critical status than those without AF. Patients with AF showed a significant increase in the risk of all-cause mortality (OR: 3.97, 95% CI: 2.76-5.71), with a high degree of heterogeneity. A sensitivity analysis focusing on new-onset AF showed the consistency of these results.

CONCLUSIONS

Among COVID-19 patients, AF is found in 8% of patients. AF COVID-19 patients are older, more hypertensive, and more likely to have a critical status. In COVID-19 patients, AF is associated with a 4-fold higher risk of death. Further studies are needed to define the best treatment strategies to improve the prognosis of AF COVID-19 patients.

Prognosis and management of new-onset atrial fibrillation in critically ill patients

Introduction

The prognosis of new-onset atrial fibrillation (AF) compared with that of preexisting and non-AF remains controversial. The purpose of this study was to evaluate the effect of new-onset AF compared with preexisting and non-AF on hospital and 90-day mortality.

Methods

A retrospective cohort study was performed using data obtained from the Medical Information Mart for Intensive Care III database. The primary outcome was 90-day mortality. Secondary outcomes included hospital mortality, hospital and intensive care unit (ICU) length of stay, and acute kidney injury. Logistic and Cox regression analyses were performed to evaluate the relationship between new-onset AF and study outcomes.

Results

A total of 38,159 adult patients were included in the study. The incidence of new-onset AF was 9.4%. Ninety-day mortality, hospital mortality, and hospital and ICU length of stay in patients with new-onset and preexisting AF were significantly increased compared with those in patients with non-AF patients (all p < 0.001). After adjusting for patient characteristics, new-onset AF remained associated with increased 90-day mortality compared with non-AF (adjusted hazard ratio (HR) 1.37, 95% confidence interval (CI) 1.26 to 1.50; p < 0.01) and preexisting AF (adjusted HR 1.12; 95%-CI 1.02 to 1.23; p < 0.01). Patients in the surgical intensive care unit (SICU) had significantly higher 90-day mortality than patients in the coronary care unit (adjusted HR 1.30; 95% CI 1.31 to 1.51; p < 0.001).

Conclusions

Critically ill patients with new-onset AF have significantly increased hospital and 90-day mortality compared with patients with preexisting and non-AF. Patients with new-onset AF in the ICU, especially those in the SICU, require robust management measures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02039-w.

Hospital outcomes associated with new-onset atrial fibrillation during ICU admission: A multicentre competing risks analysis

PURPOSE

New onset atrial fibrillation (NOAF) in critically ill patients has been associated with increased short-term mortality. Analyses that do not take into account the time-varying nature of NOAF can underestimate its association with hospital outcomes. We investigated the prognostic association of NOAF with hospital outcomes using competing risks methods.

MATERIALS AND METHODS

We undertook a retrospective cohort study in three general adult intensive care units (ICUs) in the UK from June 2008 to December 2015. We excluded patients with known prior atrial fibrillation or an arrhythmia within four hours of ICU admission. To account for the effect of NOAF on the rate of death per unit time and the rate of discharge alive per unit time we calculated subdistribution hazard ratios (SDHRs).

RESULTS

Of 7541 patients that fulfilled our inclusion criteria, 831 (11.0%) developed NOAF during their ICU admission. NOAF was associated with an increased duration of hospital stay (CSHR 0.68 (95% CI 0.63-0.73)) and an increased rate of in-hospital death per unit time (CSHR 1.57 (95% CI 1.37-1.1.81)). This resulted in a strong prognostic association with dying in hospital (adjusted SDHR 2.04 (1.79-2.32)). NOAF lasting over 30 min was associated with increased hospital mortality.

CONCLUSIONS

Using robust methods we demonstrate a stronger prognostic association between NOAF and hospital outcomes than previously reported.

New-onset atrial fibrillation and associated outcomes and resource use among critically ill adults-a multicenter retrospective cohort study

BACKGROUND

New-onset atrial fibrillation (NOAF) is commonly encountered in critically ill adults. Evidence evaluating the association between NOAF and patient-important outcomes in this population is conflicting. Furthermore, little is known regarding the association between NOAF and resource use or hospital costs.

METHODS

Retrospective analysis (2011-2016) of a prospectively collected registry from two Canadian hospitals of consecutive ICU patients aged ≥ 18 years. We excluded patients with a known history of AF prior to hospital admission. Any occurrence of atrial fibrillation (AF) was prospectively recorded by bedside nurses. The primary outcome was hospital mortality, and we used multivariable logistic regression to adjust for confounders. We used a generalized linear model to evaluate contributors to total cost.

RESULTS

We included 15,014 patients, and 1541 (10.3%) had NOAF during their ICU admission. While NOAF was not associated with increased odds of hospital death among the entire cohort (adjusted odds ratio [aOR] 1.02 [95% confidence interval [CI] 0.97-1.08]), an interaction was noted between NOAF and sepsis, and the presence of both was associated with higher odds of hospital mortality (aOR 1.28 [95% CI 1.09-1.36]) than either alone. Patients with NOAF had higher total costs (cost ratio [CR] 1.09 [95% CI 1.02-1.20]). Among patients with NOAF, treatment with a rhythm-control strategy was associated with higher costs (CR 1.24 [95% CI 1.07-1.40]).

CONCLUSIONS

While NOAF was not associated with death or requiring discharge to long-term care among critically ill patients, it was associated with increased length of stay in ICU and increased total costs.

Atrial Fibrillation in Patients with Septic Shock: A One-Year Observational Pilot Study

Objective

The negative effect of sepsis on the myocardium affects its electric functionality. This study aims to evaluate the incidence of atrial fibrillation (AF) in patients with septic shock, and the mortality rate of patients with AF versus patients that maintained sinus rhythm (SR).

Methods

This is a one-year observational prospective pilot study. It was conducted at the Department of Anaesthesia and Intensive Care of Pisa University. Patients with septic shock were enrolled in this study. They were divided in two groups based on the occurrence of AF while in the ICU. Data were collected at admission and after 72 hours, and the data consisted of anamnesis, vital parameters, blood results and severity score.

Results

Out of 27 patients, 9 developed AF during the first 72 hours. At admission and at 72 hours, SOFA was statistically higher in the patients with AF (p=0.012 and p=0.002, respectively). In the AF group, the overall mortality was 66.7%, whereas, it was 11.1% (p=0.006) in the patients with SR. Age, rhythm and noradrenaline dosage were univariate predictors of total mortality.

Conclusion

In patients with septic shock, AF has a high incidence, and it correlated with a worse outcome. Patients with higher SOFA score are at a greater risk of developing arrhythmia.

Atrial Fibrillation in the ICU

Atrial fibrillation (AF) is the most common arrhythmia encountered in the ICU. Preexisting AF is highly prevalent among older patients with chronic conditions who are at risk for critical illness, whereas new-onset AF can be triggered by accelerated atrial remodeling and arrhythmogenic triggers encountered during critical illness. The acute loss of atrial systole and onset of rapid ventricular rates that characterize new-onset AF often lead to decreased cardiac output and hemodynamic compromise. Thus, new-onset AF is both a marker of disease severity as well as a likely contributor to poor outcomes, similar to other manifestations of organ dysfunction during critical illness. Evaluating immediate hemodynamic effects of new-onset AF during critical illness is an important component of rapid clinical assessment aimed at identifying patients in need of urgent direct current cardioversion, treatment of reversible inciting factors, and identification of patients who may benefit from pharmacologic rate or rhythm control. In addition to acute hemodynamic effects, new-onset AF during critical illness is associated with both short- and long-term increases in the risk of stroke, heart failure, and death, with AF recurrence rates of approximately 50% within 1 year following hospital discharge. In the absence of a strong evidence base, there is substantial practice variation in the choice of strategies for management of new-onset AF during critical illness. We describe acute and long-term evaluation and management strategies based on current evidence and propose future avenues of investigation to fill large knowledge gaps in the management of patients with AF during critical illness.