Interatrial block and abnormal P-wave electrocardiographic parameters as non-invasive predictors of atrial fibrillation

Aim. To identify noninvasive markers of atrial electrical dysfunction and risk of nonvalvular atrial fibrillation (AF) and to develop a predictive mathematical model to estimate the AF risk based on electrocardiographic (ECG) P-wave parameters during sinus rhythm. Methods. The study included 211 patients with cardiovascular pathology (aged median 62 52; 71 years, 67.8% male, NYHA heart failure class I-III). All patients (follow-up median 45 26; 67 months) underwent a complex of studies: 12-lead ECG, echocardiography, 24-hour ECG monitoring. Based on surface ECG data during sinus rhythm, parameters of atrial electrical activation were assessed such as Morphology, Voltage and P waves duration (MVP) according to integral analysis by MVP score. Results. During 3.7-year period, 44 (20.8%) patients experienced new-onset sustained AF and 12 (5.69%) patients developed ischemic stroke. As a result of ROC analysis and univariate Cox regression, independent predictors of AF were identified: P-wave prolongation in the DII lead, 3rd degree or advanced interatrial block (aIAB), an increase P-wave terminal force in lead V 1 (PTFV 1 ), low-voltage P-wave in the DI lead and сalculated level of abnormal P-wave ≥3 points on the MVP score. Data from multivariate Cox proportional hazards regression analysis confirmed the prognostic significance for three independent predictors of AF: aIAB (hazard ratio (HR) 5.92; 95% confidence interval (CI) 2.48-4.12; p=0.0001); PTFV 1 (HR 1.14; 95% CI 1.04-1.24, p=0.003); low-voltage P-wave in lead DI <0.1 mV (HR 1.03; 95% CI 1.02-1.05; p=0.0001); and as a result a mathematical model was created to predict AF risk (-2LL =258; χ 2 =105; p=0.0001). Predictors such as PTFV 1 (HR 1.41; 95% CI 1.17-1.72, p=0.0001) and MVP score of abnormal P-waves (HR 1.85; 95% CI 1.27-1.72 2.70], p=0.001) were associated with a high risk of stroke according to Cox regression model (-2LL= 62.5; χ 2 =38.4; p <0.001). Conclusion. Complex of ECG markers of atrial electrical dysfunction such as aIAB, PTFV 1 , level MVP score of abnormal P-wave and low P-wave voltage allows identifying patients at high risk of AF and ischemic stroke.