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Predictive value of aortic knob width for postoperative atrial fibrillation in coronary artery bypass surgery
Kemalettin Erdem1, Serkan Oztürk, Selim Ayhan
1Departments of Cardiovascular Surgery Faculty of Medicine, Abant İzzet Baysal University; Bolu-Turkey. drkemalettincvs@yahoo.com.
Insights
Aortic knob width (AKW) is significantly associated with atrial fibrillation (AF) development after coronary artery bypass surgery (CABG). Increased AKW on chest X-ray may predict postoperative AF (POAF) risk.
Area of Science:
- Cardiology
- Radiology
- Thoracic Surgery
Background:
- Atrial fibrillation (AF) is a common complication following coronary artery bypass surgery (CABG).
- Predictive markers for postoperative AF (POAF) are crucial for risk stratification and management.
- Aortic knob width (AKW) is a measurable parameter on chest radiography.
Purpose of the Study:
- To determine the association between aortic knob width (AKW) and the incidence of atrial fibrillation (AF) after isolated coronary artery bypass surgery (CABG).
Main Methods:
- Retrospective observational cohort study of 135 patients undergoing isolated CABG.
- Aortic knob width (AKW) measured via digital chest X-ray.
- Logistic regression and ROC analysis to assess AKW's association with and diagnostic value for POAF.
Main Results:
- Postoperative AF (POAF) occurred in 31.8% of patients.
- Higher AKW, left atrial diameter, and C-reactive protein levels were significantly associated with POAF.
- AKW independently predicted POAF (OR=4.527), with a cut-off of 36.5 mm showing 84.4% sensitivity (AUC=0.84).
Conclusions:
- A significant association exists between aortic knob width (AKW) and atrial fibrillation (AF) development post-CABG.
- PA chest radiography provides a cost-effective and accessible method for assessing POAF risk using AKW.
- Cardiovascular surgeons can easily utilize AKW measurements in clinical practice.
Objective:
The aim of our study was determine whether aortic knob width (AKW) is associated with the development of atrial fibrillation (AF) after isolated coronary artery bypass surgery (CABG).
Methods:
In this retrospective observational cohort study, we evaluated 135 patients without hemodynamically significant valvular problems. AKW was measured on chest X-ray by digital system. Multiple logistic regression analysis was used to find independent associates of postoperative AF (POAF). The diagnostic value of AKW was assessed using ROC analysis.
Results:
POAF occurred in 43 (31.8%) of all patients. The age, AKW, left atrial (LA) diameter and C-reactive protein (CRP) were significantly higher in patients with POAF than without POAF (67.2 ± 8.6 vs 61.3 ± 9.8 years, p=0.004; 45.6 ± 5.8 vs 36.1 ± 3.8 mm, p<0.001; 37.9 ± 3.5 vs 35.8 ± 3.1mm, p=0.002 and 10.6 ± 8.5 vs 5.6 ± 6.5 mg/L, p=0.001 respectively). Multiple logistic regression analysis demonstrated that AKW, LA diameter and CRP were independently associated with POAF (OR=4.527, 95% CI=1.315 -15.588, p=0.017; OR=2.834, 95% CI=1.091-7.360, p=0.032 and OR=1.300, 95% CI=1.038-1.628, p=0.022 respectively). ROC analysis has demonstrated that aortic knob of 36.5 mm constitutes the cut-off value for the occurrence of POAF with 84.4% sensitivity and 64.6% specificity (AUC=0.84, 95% CI=0.75-0.94, p<0.001).
Conclusion:
We have demonstrated a significant association between the AKW and AF development after isolated CABG. PA chest radiography is a cheap and readily available clinical tool and it can be examined easily by every cardiovascular surgeons.
