Atrial fibrillation in the surgical intensive care unit: Common but understudied

A machine learning-based predictive model for the in-hospital mortality of critically ill patients with atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is common among intensive care unit (ICU) patients and significantly raises the in-hospital mortality rate. Existing scoring systems or models have limited predictive capabilities for AF patients in ICU. Our study developed and validated machine learning models to predict the risk of in-hospital mortality in ICU patients with AF.

METHODS AND RESULTS

Medical Information Mart for Intensive Care (MIMIC)-IV dataset and eICU Collaborative Research Database (eICU-CRD) were analyzed. Among ten classifiers compared, adaptive boosting (AdaBoost) showed better performance in predicting all-cause mortality in AF patients. A compact model with 15 features was developed and validated. Both the all variable and compact models exhibited excellent performance with area under the receiver operating characteristic curves (AUCs) of 1(95%confidence interval [CI]: 1.0-1.0) in the training set. In the MIMIC-IV testing set, the AUCs of the all variable and compact models were 0.978 (95% CI: 0.973-0.982) and 0.977 (95% CI: 0.972-0.982), respectively. In the external validation set, the AUCs of all variable and compact models were 0.825 (95% CI: 0.815-0.834) and 0.807 (95% CI: 0.796-0.817), respectively.

CONCLUSION

An AdaBoost-based predictive model was subjected to internal and external validation, highlighting its strong predictive capacity for assessing the risk of in-hospital mortality in ICU patients with AF.

Clinical review: treatment of new-onset atrial fibrillation in medical intensive care patients--a clinical framework

Atrial fibrillation occurs frequently in medical intensive care unit patients. Most intensivists tend to treat this rhythm disorder because they believe it is detrimental. Whether atrial fibrillation contributes to morbidity and/or mortality and whether atrial fibrillation is an epiphenomenon of severe disease, however, are not clear. As a consequence, it is unknown whether treatment of the arrhythmia affects the outcome. Furthermore, if treatment is deemed necessary, it is not known what the best treatment is. We developed a treatment protocol by searching for the best evidence. Because studies in medical intensive care unit patients are scarce, the evidence comes mainly from extrapolation of data derived from other patient groups. We propose a treatment strategy with magnesium infusion followed by amiodarone in case of failure. Although this strategy seems to be effective in both rhythm control and rate control, the mortality remained high. A randomised controlled trial in medical intensive care unit patients with placebo treatment in the control arm is therefore still defendable.