Atrial fibrillatory rate and risk of left atrial thrombus in atrial fibrillation
Förlag: OXFORD UNIV PRESS
Aims In atrial fibrillation (AF), a relation between electrocardiogram (ECG) fibrillatory wave amplitude and thrombus formation has been sought for tong with conflicting results. In contrast, the possible relation between atrial. fibrillatory rate obtained from the surface ECG and left atrial. thrombus formation in patients with AF is unknown and was consequently evaluated in this study. Methods and results One-hundred and twenty-five patients (mean age 64 +/- 12 years, 72% mate) with persistent non-valvular AF (mean duration 28 +/- 80 days) undergoing transesophageal echocardiography were studied. In all patients, standard 12-lead ECG recordings were acquired before the examination. Atrial. fibrillatory rate was determined using spatiotemporal QRST cancellation and time-frequency analysis of lead V1. Atrial. fibrillatory rate measured 401 +/- 63 fibrillations per minute (fpm, range 235-566 fpm) and was related with age (R = -0.326, P < 0.001), ventricular rate (R = -0.202, P = 0.024), gender (407 +/- 62 in mates vs. 387 + 64 fpm in females, P = 0.038) but not AF duration (R = 0.088, P = 0.374), presence of lone AF (408 +/- 66 vs. 394 +/- 58 fpm, P = 0.228), or beta-blocker or calcium channel blocker treatment (398 +/- 63 vs. 405 +/- 62 fpm, P = 0. 556). Age was the only independent predictor of fibrillatory rate (B = - 1.714, P < 0.001). In patients with left atrial. thrombus (n = 10), spontaneous echo contrast (SEC) was more frequently present (70 vs. 29 %, p = 0.007) and left atrial, appendage (LAA) outflow velocity was lower (26 +/- 20 vs. 37 +/- 15 cm/s, P = 0.012) than in patients without thrombus (n = 115). In contrast, mean fibrillatory rate, which showed a weak inverse correlation with LAA velocity (R = -0. 118, P = 0.048) was not different between both groups (380 +/- 56 vs. 403 +/- 63 fpm, P = 0.226). Similarly, presence of thrombus and SEC combined was not related with fibrillatory rate. Conclusion Atrial. fibrillatory rate obtained from surface ECG lead V1 is not a risk marker for left atrial. thrombus formation in AF.
- Medicine and Health Sciences
- atrial fibrillation
- ISSN: 1099-5129