New-onset atrial fibrillation (AF) during suspected infection in a patient meets the Sepsis-3 conceptual criteria of acute organ dysfunction associated with a high risk for mortality.
In fact, new-onset AF is associated with increased mortality that is proportional to a rise in the Sequential Organ Failure Assessment (SOFA) score of approximately 4 points. The current study used Medical Information Mart for Intensive Care between 2008 and 2012 to refashion methods used to create the Sepsis-3 definition. The results of the analysis were published in the Annals of the American Thoracic Society.
Researchers hypothesized that new-onset AF during sepsis is a readily observable, “life-threatening organ dysfunction due to a dysregulated response to infection.” They tested this theory by investigating the additional prognostic value of considering new-onset AF during sepsis as a form of “cardiovascular dysfunction” within the current framework of Sepsis-3. They identified new-onset AF that was temporally related to suspected infection (ie, 48 hours pre-suspected infection to 24 hours post-suspected infection) with the use of previously validated hourly nurse-documented cardiac rhythm.
Univariable and multivariable logistic regression was used to assess the predictive ability of new-onset AF for hospital mortality. A total of 9528 patients with suspected infection were included in the study, with 233 of those patients developing new-onset AF following admission to the intensive care unit (ICU).
New-onset AF was associated with increased rates of hospital mortality in an unadjusted model (odds ratio [OR], 2.54; 95% CI, 1.94-3.32), as well as when added to the Sepsis-3 model (OR, 1.78; 95% CI, 1.34-2.38).
Each 1-point increase in the maximum SOFA score was associated with an increased risk for hospital mortality in an unadjusted model (OR, 1.18; 95% CI, 1.16-1.20), and in the Sepsis-3 model that included new-onset AF (OR, 1.18; 95% CI, 1.16-1.19). In addition, new-onset AF demonstrated similar associations with mortality in patients with cardiovascular scores <2 (OR, 1.72; 95% CI, 1.14-2.59) or ≥2 (OR, 2.41; 95% CI, 1.63-3.56; P =.21). In fact, new-onset AF developed in 33 patients coincident with or antecedent to fulfilling Sepsis-3 criteria.
A major study limitation is the fact that the ICU cohort evaluated almost certainly underestimated the number of patients who developed new-onset AF prior to meeting Sepsis-3 criteria, most likely because those patients had higher SOFA scores than patients in a non-ICU population. Therefore, study findings probably provide conservative estimates. Additional studies are warranted that examine how new-onset AF may have an effect on prognostic validity outside of the ICU.
Bosch NA, Massaro JM, Winter MR, et al. New-onset atrial fibrillation as a sepsis defining organ failure [published online June 26, 2019]. Ann Am Thorac Soc. doi:10.1513/AnnalsATS.201902-176RL