Objective To observe the value of nomogram based on echocardiographic functional parameters of left atrium(LA)for identifying atrial fibrillation(AF).Methods Sixty-six adult patients with AF and 65 individuals without AF were retrospectively enrolled and randomly divided into training set(n=79)and test set(n=52).Four-dimensional LA volumetric echocardiography was performed,and LA volume and strain parameters were measured using four-dimensional left atrial automatic quantification(4D LAQ)technology.Echocardiographic parameters were compared between AF group(n=38)and non-AF group(n=41)in training set,and a logistic regression model for identifying AF was constructed.The performance of the model was evaluated with receiver operating characteristic(ROC)curve and the area under the curve(AUC).Then a nomogram was developed based on the logistic regression model,and the calibration was assessed using a calibration curve,as well as the clinical net benefit was evaluated through decision curve analysis(DCA).Results In training set,compared to those in non-AF group,LA diameter(LAD),the minimum LA volume(LAVmin),the maximum LA volume(LAVmax)and the maximum LA volume index(LAVImax)increased,while the left ventricular ejection fraction(LVEF),LA emptying volume(LAEV),LA emptying fraction(LAEF),and the magnitude of LA reservoir longitudinal strain(LASr)and LA reservoir circumferential strain(LASr_c)decreased in AF group(all P＜0.05).LASr(OR[95％CI]=0.780[0.636,0.956])and LAEF(OR[95％CI]=0.850[0.757,0.954])were both independently associated with AF.The logistic regression model constructed for identifying AF achieved an AUC of 0.950 in training set and 0.955 in test set.The nomogram demonstrated good calibration and provided a certain level of net clinical benefit.Conclusion Nomogram constructed on basis of LASr and LAEF was effective for identifying AF.

Objective To observe the value of nomogram based on echocardiographic functional parameters of left atrium(LA)for identifying atrial fibrillation(AF).Methods Sixty-six adult patients with AF and 65 individuals without AF were retrospectively enrolled and randomly divided into training set(n=79)and test set(n=52).Four-dimensional LA volumetric echocardiography was performed,and LA volume and strain parameters were measured using four-dimensional left atrial automatic quantification(4D LAQ)technology.Echocardiographic parameters were compared between AF group(n=38)and non-AF group(n=41)in training set,and a logistic regression model for identifying AF was constructed.The performance of the model was evaluated with receiver operating characteristic(ROC)curve and the area under the curve(AUC).Then a nomogram was developed based on the logistic regression model,and the calibration was assessed using a calibration curve,as well as the clinical net benefit was evaluated through decision curve analysis(DCA).Results In training set,compared to those in non-AF group,LA diameter(LAD),the minimum LA volume(LAVmin),the maximum LA volume(LAVmax)and the maximum LA volume index(LAVImax)increased,while the left ventricular ejection fraction(LVEF),LA emptying volume(LAEV),LA emptying fraction(LAEF),and the magnitude of LA reservoir longitudinal strain(LASr)and LA reservoir circumferential strain(LASr_c)decreased in AF group(all P＜0.05).LASr(OR[95％CI]=0.780[0.636,0.956])and LAEF(OR[95％CI]=0.850[0.757,0.954])were both independently associated with AF.The logistic regression model constructed for identifying AF achieved an AUC of 0.950 in training set and 0.955 in test set.The nomogram demonstrated good calibration and provided a certain level of net clinical benefit.Conclusion Nomogram constructed on basis of LASr and LAEF was effective for identifying AF.