P Wave Duration/P Wave Voltage Ratio Plays a Promising Role in the Prediction of Atrial Fibrillation: A New Player in the Game

Abstract

Background. Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice. Identification of patients at risk for developing AF and the opportunity for early targeted intervention might have a significant impact on morbidity and mortality. Prolonged P wave duration and decreased P wave voltage have been shown to be independent predictors of AF. The present study aimed to investigate the role of P wave duration/P wave voltage in predicting new-onset AF. Methods. We screened a total of 640 consecutive patients who admitted to cardiology outpatient clinic with a complaint of palpitation between 2012 and 2014. 24-h Holter monitoring, echocardiography, and electrocardiography (ECG) recordings were reviewed to identify new-onset AF. Patients were assigned into two groups based on presence (n = 150) and absence (n = 490) of new-onset AF. Previous ECGs with sinus rhythm were analyzed. P wave duration was measured in inferior leads, and P wave voltage was measured in lead one. P wave duration/P wave voltage was also calculated for each patient. Results. One hundred fifty subjects (23.4%) had new-onset AF among 640 patients. P wave duration (123.27 ± 12.87 vs. 119.33 ± 17.39 ms, $p=0.024$ ) and P wave duration/P wave voltage (1284.70 ± 508.03 vs. 924.14 ± 462.06 ms/mV, $p<0.001$ ) were higher, and P wave voltage (0.12 ± 0.04 vs. 0.13 ± 0.04 mV, $p<0.001$ ) was significantly lower in the new-onset AF group compared with non-AFs. P wave duration/P wave voltage, with a cut off of 854.5 ms/mV, had 83.3% sensitivity and 62.0% specificity in a receiver operating characteristic curve (AUC 0.728, 95% CI 0.687–0.769; $p<0.001$ ). Their negative and positive predictive values were 78.7% and 68.6%, respectively. In a univariate regression analysis, age, smoking, C-reactive protein, brain natriuretic peptide, left atrial diameter, left atrial volume index, P wave duration, P wave voltage, and P wave duration/P wave voltage were significantly associated with the development of new-onset AF. Moreover, smoking (OR 4.008, 95% CI 1.707–9.409; $p=0.001$ ), left atrial volume index (OR 7.108, 95% CI 4.400–11.483; $p<0.001$ ), and P wave duration/P wave voltage (OR 1.002, 95% CI 1.000–1.003; $p=0.044$ ) were found to be significant independent predictors of new-onset AF in a multivariate analysis, after adjusting for other risk parameters. Conclusion. The P wave duration/P wave voltage ratio is a practical, easy-to-use, cheap, and reliable electrocardiographic parameter, which can play a promising role for both in predicting and elucidating a mechanism of new-onset AF.