• atrial fibrillation;
  • P wave;
  • signal-averaged electrocardiogram;
  • cardioversion

GUO, X.H., et al.: Prognostic Significance of Serial P Wave Signal-Averaged Electrocardiograms Following External Electrical Cardioversion for Persistent Atrial Fibrillation: A Prospective Study.The authors hypothesized that the persistence of abnormal atrial conduction detected by serial P wave signal-averaged electrocardiograms (P-SAECGs) can identify patients who are at high risk of recurrent atrial fibrillation (R-AF) following electrical cardioversion (ECV). P-SAECGs were recorded in 60 consecutive patients after ECV (53 men, age 66 ± 10 years) and repeated in those who had remained in sinus rhythm (SR) 1 week, and 1, 3, and 6 months later. Filtered P wave duration (PD), root mean square (RMS) voltage of the terminal 40, 30, 20 ms (RMS-40, RMS-30, RMS-20) of the filtered P wave, RMS voltage of the entire filtered P wave (RMS-p), and the integral of the voltages in the entire P wave (integral-p) were analyzed. Thirty-one (52%) patients returned to AF within 1 week, an additional 11 (18%) by 1 month, and a further 2 (3.3%) at each subsequent assessment (3 and 6 months). The patients with R-AF had longer PD(157 ± 24 vs 143 ± 17 ms, P < 0.0001)and lower RMS-40, RMS-30, RMS-20 (5.3 ± 2.0vs6.1 ± 3.4 μV, P = 0.007; 4.3 ± 1.5vs5.7 ± 3.2 μV, P < 0.0001; 3.6 ± 1.4vs5.2 ± 3.0 μV, P < 0.0001, respectively) than those who remained in SR. These measurements did not change significantly in either group. RMS-p increased in SR patients(P = 0.009)but decreased in those who subsequently reverted to AF(P = 0.032)with a significant difference between the slopes of the RMS-p change(P = 0.006). Integral-p decreased from the time of ECV in the R-AF group only(P = 0.0028)and created a significant difference between the two slopes(P = 0.0004). The evolution of P-SAECG parameters after ECV differs in patients whose AF recurs versus patients who remain in SR. (PACE 2003; 26[Pt. II]:299–304)