Open AccessEffects of heart rate on flow velocity of the left atrial appendage in patients with nonvalvular atrial fibrillation
Author(s) -
Noda Toshiyuki,
Arakawa Michio,
Mrwa Hiroshi,
Ito Yoshimi,
Kagawa Kensaku,
Nishigaki Kazuhiki,
Hirakawa Senri,
Fujiwara Hisayoshi
Publication year - 1996
Publication title -
clinical cardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.263
H-Index - 72
eISSN - 1932-8737
pISSN - 0160-9289
DOI - 10.1002/clc.4960190404
Subject(s) - medicine , cardiology , atrial fibrillation , diastole , systole , blood flow , appendage , heart rate , thrombus , atrial appendage , hemodynamics , flow velocity , doppler echocardiography , left atrium , blood pressure , anatomy , sinus rhythm , relaxation (psychology)
Background and hypothesis : Flow velocity of the left atrial appendage (LAA) is thought to be important in thrombus formation in association with blood stasis and the development of spontaneous echo contrast. The effects of heart rate on peak flow velocity of the LAA have not been studied in patients with nonvalvular atrial fibrillaton. Methods : Using transesophageal Doppler echocardiography, peak flow velocity of the LAA was measured at the junction between the left atrium and the LAA during left ventricular (LV) systole and diastole in 21 patients with nonvalvular atrial fibrillation. In six cases, the average peak flow velocity of the LAA for 10 consecutive beats with moderately long R‐R intervals (LI beats) was compared with those for 3‐5 consecutive beats with extremely short R‐R intervals (SI bets). Results : Average peak flow velocity of the LAA during LV diastole was significantly higher than that during LV systole (26.5 ± 15.7 vs. 19.3 ± 10.4 cm/s, p<0.01). In SI beats, average peak flow velocity of the LAA was significantly lower than that in LI beats (17.1 ± 12.1 vs. 21.2 ± 12.9 cm/s, p<0.01). Conclusion : An increased heart rate reduced the peak flow velocity of the LAA in patients with nonvalvular atrial fibrillation, which would promote blood stasis in the LAA.