OBJECTIVE: To prospectively determine whether ventricular rate and regularity are significant determinants of the velocity and magnitude of left atrial appendage (LAA) flow. DESIGN AND PATIENTS: 12 patients with atrial fibrillation (AF), high degree atrioventricular block, and indwelling permanent pacemakers were studied. SETTING: Cardiology department of a tertiary referral centre. INTERVENTIONS: Pacing was triggered by an external programmable transcutaneous device. Patients were paced at 60, 120, and 150 beats/min in both regular and irregular rhythm. LAA flow velocity and magnitude were assessed with transoesophageal Doppler echocardiography. MAIN OUTCOME MEASURES: Peak and mean LAA inflow and outflow velocity, and time-velocity interval (TVI) of LAA flow. RESULTS: Increasing ventricular rate was associated with significantly lower peak inflow (p < 0.01), peak outflow (p < 0.05), mean inflow (p < 0.01), and mean outflow (p < 0.05) velocities and with a lower TVI of LAA filling and emptying velocities (p < 0.01). This effect was noted at rates of 60 beats/min compared with both 120 and 150 beats/min. At a pacing rate of 120 beats/min there was a significantly higher total TVI when pacing at a regular than at an irregular rhythm (40.16 (14.6) cm v 30.74 (10.9) cm, p < 0.05). CONCLUSIONS: In this study, LAA filling velocities in patients in AF were significantly influenced by paced ventricular rate and to a much lesser extent ventricular rhythm. These results suggest that rapid ventricular rates may predispose to stasis in the LAA in AF.
OBJECTIVE: To prospectively determine whether ventricular rate and regularity are significant determinants of the velocity and magnitude of left atrial appendage (LAA) flow. DESIGN AND PATIENTS: 12 patients with atrial fibrillation (AF), high degree atrioventricular block, and indwelling permanent pacemakers were studied. SETTING: Cardiology department of a tertiary referral centre. INTERVENTIONS: Pacing was triggered by an external programmable transcutaneous device. Patients were paced at 60, 120, and 150 beats/min in both regular and irregular rhythm. LAA flow velocity and magnitude were assessed with transoesophageal Doppler echocardiography. MAIN OUTCOME MEASURES: Peak and mean LAA inflow and outflow velocity, and time-velocity interval (TVI) of LAA flow. RESULTS: Increasing ventricular rate was associated with significantly lower peak inflow (p < 0.01), peak outflow (p < 0.05), mean inflow (p < 0.01), and mean outflow (p < 0.05) velocities and with a lower TVI of LAA filling and emptying velocities (p < 0.01). This effect was noted at rates of 60 beats/min compared with both 120 and 150 beats/min. At a pacing rate of 120 beats/min there was a significantly higher total TVI when pacing at a regular than at an irregular rhythm (40.16 (14.6) cm v 30.74 (10.9) cm, p < 0.05). CONCLUSIONS: In this study, LAA filling velocities in patients in AF were significantly influenced by paced ventricular rate and to a much lesser extent ventricular rhythm. These results suggest that rapid ventricular rates may predispose to stasis in the LAA in AF.
Authors: D G Wyse; A L Waldo; J P DiMarco; M J Domanski; Y Rosenberg; E B Schron; J C Kellen; H L Greene; M C Mickel; J E Dalquist; S D Corley Journal: N Engl J Med Date: 2002-12-05 Impact factor: 91.245
Authors: Isabelle C Van Gelder; Vincent E Hagens; Hans A Bosker; J Herre Kingma; Otto Kamp; Tsjerk Kingma; Salah A Said; Julius I Darmanata; Alphons J M Timmermans; Jan G P Tijssen; Harry J G M Crijns Journal: N Engl J Med Date: 2002-12-05 Impact factor: 91.245
Authors: E G Daoud; R Weiss; M Bahu; B P Knight; F Bogun; R Goyal; M Harvey; S A Strickberger; K C Man; F Morady Journal: Am J Cardiol Date: 1996-12-15 Impact factor: 2.778