ABSTRACT: Patients with interatrial conduction delay may have suboptimal left atrioventricular (AV) timing due to delayed contraction of the left atrium with foreshortening of ventricular filling. This may be an issue in pacemaker patients, especially those requiring resychronization therapy. Pacing from the high interatrial septum (IAS) or the distal or proximal coronary sinus (CSD and CSP) may improve left AV synchrony compared with pacing from the right atrial appendage (RAA). Our aim was to compare haemodynamics of these pacing sites.
A total of 24 patients undergoing radiofrequency ablation for paroxysmal atrial fibrillation were studied. Left atrial pressures were recorded in sinus rhythm, and during pacing from the RAA, IAS, CSD, CSP, and with biatrial (BiA) pacing from the IAS + CSD. Amplitudes, +dP/dT(max), and timing of the a-wave were compared between recordings. Left atrial contractility, measured by +dP/dT(max), was greatest during BiA pacing (P ≤ 0.03 for all comparisons). There was a marked reduction in delay to peak a-wave when pacing from all sites compared with the RAA, with BiA pacing yielding the shortest delay (P ≤ 0.001). However, AV conduction was shortened by all alternative pacing sites, which mitigated the anticipation of left atrial contraction with respect to ventricular activation, except for BiA pacing (P < 0.001). Pacing of the IAS did not result in any improvement in haemodynamics or AV synchrony.
Multisite atrial pacing results in favourable acute atrial haemodynamics and left AV synchrony. This may be a solution in pacemaker patients with interatrial conduction delay.
Europace 04/2011; 13(9):1262-7. · 1.98 Impact Factor
ABSTRACT: Left atrial (LA) volume can be determined during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) with angiography or electro-anatomic (CARTO) mapping. We compared these volumes with LA volume measured using transthoracic real-time three-dimensional echocardiography (3DE).
One hundred and twenty-seven consecutive patients undergoing RFCA for AF were studied using biplane pulmonary vein angiography with opacification of the LA. LA volume was calculated from the diameter measurements with a formula using an ellipsoid model. A subset of 22 patients also underwent LA volume determination by CARTO mapping. These volumes were then correlated with LA volume determined non-invasively by real-time 3DE. Linear regression showed a significant correlation between LA volume determined by angiography and 3DE volume (r = 0.56, P < 0.0001). Bland-Altman analysis showed a bias of 38 +/- 22 ml by the angiographic method. LA volume measured using CARTO correlated better (r = 0.67, P < 0.001), but 3DE yielded smaller values (mean difference of -30 +/- 19 ml).
LA volume determination by angiography and CARTO mapping correlate significantly with 3DE volume. However, both invasive techniques yield larger values for LA volume. The results indicate that LA volume obtained by angiography or CARTO should not be used as baseline value for non-invasive follow-up of LA remodelling by 3DE.
Europace 02/2010; 12(6):792-7. · 1.98 Impact Factor
ABSTRACT: Reports using two-dimensional echocardiography have indicated that radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) results in a reduction in the left atrial (LA) size. Furthermore, the effect of pulmonary vein isolation (PVI) on right atrial (RA) anatomical remodelling has not been studied. Three-dimensional echocardiography (3DE) allows us to more precisely quantify atrial volume. Our aim was to assess the effect of PVI on biatrial anatomical remodelling using real-time 3DE.
We prospectively studied 91 patients (age 59 +/- 8 years, 79 males) referred for RFCA of paroxysmal (n = 79) or chronic (n = 19) AF. Left atrial and RA volumes were measured using real-time 3DE at baseline and after 6 months of follow-up. Data on AF recurrences were also collected. Left atrial volume was significantly reduced at follow-up when compared with baseline (51 +/- 16 vs. 60 +/- 21 mL, P < 0.001). The same occurred with RA volume (43 +/- 17 vs. 50 +/- 20 mL, P = 0.001). The reduction in the LA volume was more marked in patients with chronic than in those with paroxysmal AF (17 +/- 16 vs. 6 +/- 17 mL, P = 0.017). Patients with AF recurrence (23%) showed similar atrial volume reduction compared with those who were seemingly cured.
Three-dimensional echocardiography shows evidence of biatrial anatomical reverse remodelling after RFCA for AF. A reduction in the atrial volume occurs despite recurrence of AF.
Europace 09/2008; 10(9):1073-8. · 1.98 Impact Factor