Atrial Fibrillation Predictors: Importance of the Electrocardiogram

Abstract

Atrial fibrillation (AF) is the most common arrhythmia in adults and is associated with significant morbidity and mortality. Substantial interest has developed in the primary prevention of AF, and thus the identification of individuals at risk for developing AF. The electrocardiogram (ECG) provides a wealth of information, which is of value in predicting incident AF. The PR interval and P wave indices (including P wave duration, P wave terminal force, P wave axis, and other measures of P wave morphology) are discussed with regard to their ability to predict and characterize AF risk in the general population. The predictive value of the QT interval, ECG criteria for left ventricular hypertrophy, and findings of atrial and ventricular ectopy are also discussed. Efforts are underway to develop models that predict AF incidence in the general population; however, at present, little information from the ECG is included in these models. The ECG provides a great deal of information on AF risk and has the potential to contribute substantially to AF risk estimation, but more research is needed.

Keywords: P wave indices; atrial fibrillation; electrocardiogram; primary prevention; risk stratification.

Figure 1

A representative P wave and PR segment in lead V₁. The PR interval, P wave duration (Pwd), P wave amplitude (Pwa), P′ amplitude (PPa), P′ duration (PPd), and PR segment depression (PRD) are marked. The P wave terminal force (PTFV₁) is derived by multiplication of PPa by PPd.

Figure 2

The vectorcardiographic P loop morphology and the spatial P loop vector characterize atrial conduction.