Dr. Ozyigit, Dr. Kocas, Dr. Karadag, and Dr. Ozben were responsible for conception and design of the study and acquisition of data. Dr. Ozyigit and Dr. Ozben analyzed and interpreted the data and were responsible for drafting of the manuscript. All authors approved the final version of the manuscript.
P wave dispersion is a noninvasive electrocardiographic predictor for atrial fibrillation. The aim of the study was to explore relation between left atrial volume index assessed by 3-dimensional echocardiography and P wave dispersion in elderly patients.
Seventy-three consecutive patients over the age of 65 (mean age: 75 ± 7 years, 17 men) were included. P wave dispersion is calculated as the difference between maximum and minimum P wave durations. Left atrial volume index was measured by both 2-dimensional and 3-dimensional echocardiography and categorized as normal (≤ 34 mL/m2) or increased (mild, 35–41 mL/m2; moderate, 42–48 mL/m2; severe, ≥ 49 mL/m2).
Thirty-one patients had normal left atrium while 24 patients had mildly enlarged, nine had moderately enlarged, and nine had severely enlarged left atrium. Prolongation of P wave dispersion was more prevalent in patients with dilated left atrium. P wave dispersion was significantly correlated with both 2-dimensional (r = 0.600, p < 0.001) and 3-dimensional left atrial volume index (r = 0.688, p < 0.001). Both left atrial volume indexes were associated with prolonged P wave dispersion when adjusted for age, sex, presence of hypertension, and left ventricular mass index. Receiver-operator characteristic (ROC) analysis revealed that a 3-dimensional left atrial volume index ≥ 25 mL/m2 separated patients with prolonged P wave dispersion with a sensitivity of 82.2 %, specificity of 67.9 %, positive predictive value of 80.4 %, and negative predictive value of 70.4 %.
In elderly patients, 3-dimensional left atrial volume index showed a better correlation with P wave dispersion and might be helpful in discriminating patients with prolonged P wave dispersion, who might be prone to atrial fibrillation.