Doppler echocardiographic prediction of recurrent atrial fibrillation following cardioversion

Cardioversion for atrial fibrillation (AF) is associated with impairment of left atrial mechanical function and increased risk of thrombus formation with subsequent embolisation. Measuring atrial mechanical function is of interest to determine the individual risk of thromboembolism and the risk of recurrent AF.

We included 112 consecutive patients with AF and planned cardioversion. Serial echocardiographic measurements of left atrial size and Doppler measurement of mitral valve peak A wave velocities were obtained at days 0, 1, 2, 3, and 28 following cardioversion. These measurements and clinical parameters were related to clinical events and recurrent AF within 4 weeks following cardioversion. Cardioversion was achieved in 100 patients.

AF-recurrence within 4 weeks was 23.9% and 45.8% for patients with < or = and > 6 weeks AF-duration, respectively (p=0.04). Peak A wave velocities were significantly lower up to 2 days following cardioversion in patients with AF-recurrence. A peak A wave velocity < 52 cm/s at day 1 resulted in an odds ratio of 5.0 (95% CI: 1.4-18.6) for recurrence of AF. In multiple logistic regression analysis, peak A wave velocity at day 1 remained the only independent predictor of recurrent AF. Left atrial diameter did not correlate with recurrence of AF.

A single measurement of mitral peak A wave velocity 1 day following cardioversion is predictive of AF recurrence. This method is feasible for risk estimation with potential therapeutic implications.