Long-Term Impact of Newly Diagnosed Atrial Fibrillation During Critical Care: A South Korean Nationwide Cohort Study

Increased long-term mortality following new-onset atrial fibrillation in the intensive care unit: A systematic review and meta-analysis

PURPOSE

We performed a systematic review and meta-analysis to investigate the long-term outcomes of patients who develop new-onset atrial fibrillation (NOAF) during an intensive care unit (ICU) admission.

METHODS

We searched the MEDLINE and EMBASE databases from 2000 to 2022. We included studies of adults based in general ICUs that evaluated long-term outcomes (at least 30 days after hospital discharge) of NOAF. We excluded studies involving patients with a history of atrial fibrillation (AF). We performed risk of bias assessment of the included studies based on a modified Newcastle Ottawa score (NOS). We extracted summary data for long-term outcomes. Where the outcome was reported in three or more studies we pooled effect sizes.

RESULTS

We screened 2206 studies and included 15 studies reporting data from 561,797 patients. Pooled analysis of 4 studies using a random effects model revealed an association between NOAF acquired in an ICU and 90-day mortality (including ICU and hospital mortality) (RR 1.53, 95% CI 1.12-2.08). We also found an association between NOAF and 1-year mortality from 7 studies (RR 1.79, 95% CI 1.65-1.96), which remained when analysing 1-year mortality in hospital survivors (RR 1.72 (95% CI 1.49-1.98).

CONCLUSIONS

In patients who develop NOAF in an ICU, both 90-day and 1-year mortality are increased in comparison to those who do not develop NOAF. Current evidence suggests an increased risk of thromboembolic events after hospital discharge in patients who develop NOAF in an ICU.

New-onset atrial fibrillation in intensive care: epidemiology and outcomes

Aims

New-onset atrial fibrillation (NOAF) is common in patients treated on an intensive care unit (ICU), but the long-term impacts on patient outcomes are unclear. We compared national hospital and long-term outcomes of patients who developed NOAF in ICU with those who did not, before and after adjusting for comorbidities and ICU admission factors.

Methods and results

Using the RISK-II database (Case Mix Programme national clinical audit of adult intensive care linked with Hospital Episode Statistics and mortality data), we conducted a retrospective cohort study of 4615 patients with NOAF and 27 690 matched controls admitted to 248 adult ICUs in England, from April 2009 to March 2016. We examined in-hospital mortality; hospital readmission with atrial fibrillation (AF), heart failure, and stroke up to 6 years post discharge; and mortality up to 8 years post discharge. Compared with controls, patients who developed NOAF in the ICU were at a higher risk of in-hospital mortality [unadjusted odds ratio (OR) 3.22, 95% confidence interval (CI) 3.02–3.44], only partially explained by patient demographics, comorbidities, and ICU admission factors (adjusted OR 1.50, 95% CI 1.38–1.63). They were also at a higher risk of subsequent hospitalization with AF [adjusted cause-specific hazard ratio (aCHR) 5.86, 95% CI 5.33–6.44], stroke (aCHR 1.47, 95% CI 1.12–1.93), and heart failure (aCHR 1.28, 95% CI 1.14–1.44) independent of pre-existing comorbidities.

Conclusion

Patients who develop NOAF during an ICU admission are at a higher risk of in-hospital death and readmissions to hospital with AF, heart failure, and stroke than those who do not.

Management of acute atrial fibrillation in the intensive care unit: An international survey

BACKGROUND

Atrial fibrillation (AF) is common in intensive care unit (ICU) patients and is associated with poor outcomes. Different management strategies exist, but the evidence is limited and derived from non-ICU patients. This international survey of ICU doctors evaluated the preferred management of acute AF in ICU patients.

METHOD

We conducted an international online survey of ICU doctors with 27 questions about the preferred management of acute AF in the ICU, including antiarrhythmic therapy in hemodynamically stable and unstable patients and use of anticoagulant therapy.

RESULTS

A total of 910 respondents from 70 ICUs in 14 countries participated in the survey with 24%-100% of doctors from sites responding. Most ICUs (80%) did not have a local guideline for the management of acute AF. The preferred first-line strategy for the management of hemodynamically stable patients with acute AF was observation (95% of respondents), rhythm control (3%), or rate control (2%). For hemodynamically unstable patients, the preferred strategy was observation (48%), rhythm control (48%), or rate control (4%). Overall, preferred antiarrhythmic interventions included amiodarone, direct current cardioversion, beta-blockers other than sotalol, and magnesium in that order. A total of 67% preferred using anticoagulant therapy in ICU patients with AF, among whom 61% preferred therapeutic dose anticoagulants and 39% prophylactic dose anticoagulants.

CONCLUSION

This international survey indicated considerable practice variation among ICU doctors in the clinical management of acute AF, including the overall management strategies and the use of antiarrhythmic interventions and anticoagulants.

Increased risk of ischemic stroke and systemic embolism in hyperthyroidism-related atrial fibrillation: A nationwide cohort study

BACKGROUND

We aimed to evaluate the long-term risk of ischemic stroke/systemic embolism of hyperthyroidism-related AF.

METHODS

This retrospective population-based cohort study included records of 1,034,099 atrial fibrillation patients between 2005 and 2016 from the Korean National Health Insurance Service database. After exclusion, we identified 615,724 oral anticoagulation-naïve patients aged ≥18 years with new-onset non-valvular atrial fibrillation, of whom 20,773 had hyperthyroidism-related atrial fibrillation. After 3:1 propensity score matching, ischemic stroke and systemic embolism occurrences were compared between hyperthyroidism-related and non-hyperthyroidism-related ("nonthyroidal") atrial fibrillation patients.

RESULTS

After exclusion, we identified 615,724 oral anticoagulation-naïve AF patients of whom 20,773 had hyperthyroidism-related AF. Median follow-up duration was 5.9 years. Hyperthyroidism-related AF patients had significantly higher risks of ischemic stroke and systemic embolism than nonthyroidal AF patients (1.83 vs 1.62 per 100-person year, hazard ratio[HR], 1.13; 95% confidence interval[CI], 1.07 to 1.19; P < 0.001). This risk was 36% higher in hyperthyroidism-related than in nonthyroidal AF patients within 1 year of atrial fibrillation diagnosis (3.65 vs 2.67 per 100-person year, HR, 1.36; 95% CI, 1.24 - 1.50; P < 0.001). This difference was also observed in the CHA₂DS₂-VASc score subgroup analysis. The risk of ischemic stroke and systemic embolism significantly decreased in patients treated for hyperthyroidism (HR, 0.64; 95% CI, 0.58 to 0.70; P < 0.001).

CONCLUSIONS

Hyperthyroidism-related AF patients have high risks of ischemic stroke and systemic embolism like nonthyroidal AF, especially when initially diagnosed. This risk is reduced by treating hyperthyroidism.

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.

Incidence and recurrence of new-onset atrial fibrillation detected during hospitalization for non-cardiac surgery: a systematic review and meta-analysis

PURPOSE

This systematic review aimed to summarize reports of the incidence and long-term recurrence of new-onset atrial fibrillation (AF) associated with non-cardiac surgery.

SOURCES

We searched CENTRAL, MEDLINE and EMBASE from inception to November 2019. We included studies that reported on the incidence of new-onset perioperative AF during hospitalization for non-cardiac surgery and/or AF recurrence in such patients following discharge. Reviewers screened articles and abstracted data independently and in duplicate. We assessed study quality by appraising methodology for collecting AF history, incident AF during hospitalization, and AF recurrence after discharge.

PRINCIPAL FINDINGS

From 39,233 citations screened, 346 studies that enrolled a total of 5,829,758 patients met eligibility criteria. Only 27 studies used prospective, continuous inpatient electrocardiographic (ECG) monitoring to detect incident AF. Overall, the incidence of postoperative AF during hospitalization ranged from 0.004 to 50.3%, with a median [interquartile range] of 8.7 [3.8-15.0]%. Atrial fibrillation incidence varied with type of surgery. Prospective studies using continuous ECG monitoring reported significantly higher incidences of AF than those that did not (13.9% vs 1.9%, respectively; P < 0.001). A total of 13 studies (25,726 patients) with follow-up up to 5.4 years reported on AF recurrence following hospital discharge; only one study used a prospective systematic monitoring protocol. Recurrence rates ranged from 0 to 37.3%.

CONCLUSIONS

Rates of AF incidence first detected following non-cardiac surgery and long-term AF recurrence vary markedly. Differences in the intensity of ECG monitoring and type of surgery may account for this variation.

TRIAL REGISTRATION

PROSPERO (CRD42017068055); registered 1 September 2017.

Device-Detected Atrial Fibrillation Before and After Hospitalisation for Noncardiac Surgery or Medical Illness: Insights From ASSERT

BACKGROUND

Atrial fibrillation (AF) is often detected during hospitalisation for surgery or medical illness and is often assumed to be due to the acute condition.

METHODS

The Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial (ASSERT) study enrolled patients ≥ 65 years old without AF. Pacemakers or implantable cardioverter-defibrillators recorded device-detected AF. We identified participants who were hospitalised and compared the prevalence of AF before and after hospitalisation.

RESULTS

Among 2580 participants, 436 (16.9%) had a surgical or medical hospitalisation. In the 30 days following a first hospitalisation, 43 participants (9.9%, 95% confidence interval [CI] 7.2%-13.1%) had > 6 minutes of device-detected AF; 20 (4.6%, 95% CI 2.8%-7.0%) had > 6 hours. More participants had AF > 6 minutes in the 30 days following hospitalisation compared with the period 30-60 days before hospitalisation (9.9% vs 4.4%; P < 0.001). Similar results were observed for episodes > 6 hours (4.6% vs 2.3%, P = 0.03). Roughly half of participants with device-detected AF in the 30 days following hospitalisation had at least 1 episode of the same duration in the 6 months before (50% [95% CI 31.3%-68.7%] for > 6 min; 68.8% [95% CI 41.3%-89.0%] for > 6 h). Those with AF in the 30 days following hospitalisation were more likely to have had AF in the past (adjusted odds ratio [OR] 7.2, 95% CI 3.2-15.8 for > 6 min; adjusted OR 32.6, 95% CI 10.3-103.4 for > 6 h).

CONCLUSIONS

The prevalence of device-detected AF increases around the time of hospitalisation for noncardiac surgery or medical illness. About half of patients with AF around the time of hospitalisation previously had similar episodes.

Impact of atrial fibrillation in critically ill patients admitted to a stepdown unit

BACKGROUND

Limited data are available on the clinical course of patients with history of atrial fibrillation (AF) when admitted in an intensive care environment. We aimed to describe the occurrence of major adverse events in AF patients admitted to a stepdown care unit (SDU) and to analyse clinical factors associated with outcomes, impact of dicumarolic oral anticoagulant (OAC) therapy impact and performance of clinical risk scores in this setting.

MATERIALS AND METHODS

Single-centre, observational retrospective analysis on a population of subjects with AF history admitted to a SDU. Therapeutic failure (composite of transfer to ICU or death) was considered the main study outcome. Occurrence of stroke and major bleeding (MH) was considered as secondary outcomes. The performance of clinical risk scores was evaluated.

RESULTS

A total of 1430 consecutive patients were enrolled. 194 (13.6%) reported the main outcome. Using multivariate logistic regression, age (odds ratio [OR]: 1.03, 95% confidence interval [CI]: 1.01-1.05), acute coronary syndrome (OR:3.10, 95% CI: 1.88-5.12), cardiogenic shock (OR:10.06, 95% CI: 5.37-18.84), septic shock (OR:5.19,95%CI:3.29-18.84), acute respiratory failure (OR:2.49, 95% CI: 1.67-3.64) and OAC use (OR: 1.61, 95% CI: 1.02-2.55) were independently associated with main outcome. OAC prescription was associated with stroke risk reduction and to both MH and main outcome risk increase. CHA₂ DS₂ -VASc (c-index: 0.545, P = .117 for stroke) and HAS-BLED (c-index:0.503, P = .900 for MH) did not significantly predict events occurrence.

CONCLUSIONS

In critically ill AF patients admitted to a SDU, adverse outcomes are highly prevalent. OAC use is associated to an increased risk of therapeutic failure, clinical scores seem unhelpful in predicting stroke and MH, suggesting a highly individualized approach in AF management in this setting.

Canadian Critical Care Society clinical practice guideline: The use of vasopressin and vasopressin analogues in critically ill adults with distributive shock

PURPOSE

Hemodynamic management of adults with distributive shock often includes the use of catecholamine-based vasoconstricting medications. It is unclear whether adding vasopressin or vasopressin analogues to catecholamine therapy is beneficial in the management of patients with distributive shock. The purpose of this guideline was to develop an evidence-based recommendation regarding the addition of vasopressin to catecholamine vasopressors in the management of adults with distributive shock.

METHODS

We summarized the evidence informing this recommendation by updating a recently published meta-analysis. Then, a multidisciplinary panel from the Canadian Critical Care Society developed the recommendation using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology.

RESULTS

The updated systematic review identified 25 randomized controlled trials including a total of 3,737 patients with distributive shock. Compared with catecholamine therapy alone, the addition of vasopressin or its analogues was associated with a reduced risk of mortality (relative risk [RR], 0.91; 95% confidence interval [CI], 0.85 to 0.99; low certainty), reduced risk of atrial fibrillation (RR, 0.77; 95% CI, 0.67 to 0.88; high certainty), and increased risk of digital ischemia (RR, 2.56; 95% CI, 1.24 to 5.25; moderate certainty).

CONCLUSIONS

After considering certainty in the evidence, values and preferences, cost, and other factors, the expert guideline panel suggests using vasopressin or vasopressin analogues in addition to catecholamines over catecholamine vasopressors alone for the management of distributive shock (conditional recommendation, low certainty evidence).

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.

Physical Activity and Risk of Atrial Fibrillation: A Nationwide Cohort Study in General Population

Although exercise prevents cardiovascular disease and mortality, vigorous exercise and endurance athletics can cause atrial fibrillation (AF). However, no large cohort study has assessed the relationship between physical activity and AF in the general population. We assessed the effect of physical activity at different energy expenditures on the incidence of AF. We studied 501,690 individuals without pre-existing AF (mean age, 47.6 ± 14.3 years; 250,664 women [50.0%]) included in the Korean National Health Insurance Service database. The physical activity level was assessed using a standardized self-reported questionnaire at baseline. During a median follow-up of 4 years, 3,443 participants (1,432 women [41.6%]) developed AF. The overall incidence of AF at follow-up was 1.79 per 1,000 person-years. The subjects who met the recommended physical activity level (500–1,000 metabolic equivalent task [MET] minutes/week) had a 12% decreased AF risk (adjusted hazard ratio [HR]: 0.88, 95% confidence interval [CI]: 0.80–0.97), but not the insufficiently (1–500 MET-minutes/week; HR: 0.94, 95% CI: 0.86–1.03) and highly active subjects (≥1,000 MET-minutes/week; HR: 0.93, 95% CI: 0.85–1.03). The recommended minimum key target range of physical activity level was associated with the maximum benefit for reduced AF risk in the general population. The dose-response relationship between physical activity level and AF risk showed a U-shaped pattern. Although exceeding the key target range attenuated this benefit, it did not increase the AF risk beyond that during inactivity.