Atrial function and atrial fibrillation

s $7 295 Decreased fractional area change of left atrial appendage contributes to development of persistent atrial fibrillation in patients of lone paroxysmal atrial f ibr i l lat ion E.-J. Cho, H.-J. Youn, T.-H. Rho, H.-K. Jeon, H.-O. Jung, C.-J. Kim, J.-H. Kim, S.-J. Hong. Catholic University of Korea, Internal medicine, College of Medicine, Seoul, Korea, Republic of Background and Purpose: Atrial fibrillation (AF) is a progressive arrhythmia and with time, paroxysmal AF (PAr) becomes persistent. But it is uncertain whether self-terminating episodes of paroxysmal AF alter atrial mechanical function during normal sinus rhythm. This study was designed to assess the initial left atrial (LA) mechanical changes after episode of PAr with transthoracic (q-rE) and transesophageal echocardiography (TEE) that predict development of persistent AE Methods: Twenty-six consecutive patients (mean age, 594-10.6 years; 12 males) with newly diagnosed lone AF (mean duration of symptom, 2.5 days; range 1day10days) who converted to sinus rhythm spontaneously were studied prospectively. TTE and TEE were performed after 1-2 days of spontaneous sinus conversion and parameters associated with LA function and dimension were measured including LA and left atrial appendage (LAA) Fractional area change (FAC) (figure), fractional shortening (FS), ejection force (EF) and P wave to LAA ejection interval. The patients were followed up for the recurrence of AF after a year. Measurement o1 FAC o1 LAA Results: AF recurred in 11 (42.3%) patients after a mean time of 12.94-4.3 months. FAC of LAA was significantly lower in patients with AF recurrence (32.1 4-9.0% vs 49.94-20.6%, p<0.01) and multiple regression analysis indicated that FAC of LAA was an independent predictor of AF recurrence. Multiple regression analysis revealed no significant differences in LA size parameters or in clinical and LA mechanical function parameters including LA fractional shortening and ejection force recorded after restoration of sinus rhythm between patients with and without AF recurrence. Conclusion; FAC of LAA may be considered to be an independent predictor of development of recurrent and persistent AE 296 Acute left atrial reverse remodeling after pulmonary venous ablation: evaluation with tissue Doppler myocardial velocities A. Rodrigues 1 , M.A. Caldas 2, V.T. Hotta 3, M.I. Scanavacca 3, E.A. Sosa 3, C.E Pisani 3, j . Costa 3 ' W. Mathias Jr 3 1 University of Sac Paulo Medical School, Heart Institute, Sac Paulo, Brazil; 2University of Sac Paulo Medical School, Heart Institute, S&o Paulo, Brazil: 3Heart Institute (InCor), University of Sac Paulo Medical School, S&o Paulo, Brazil Non-invasive evaluation of left atrial (LA) function is challenging due to limitations in current methods. Tissue Doppler (TD) late(Am) velocities have been shown to be an alternative means of assessing LA function. Aim: To assess LA function with TD in patients with paroxysmal atrial fibrillation (AFib) at baseline and after radiofrequency (RF) ablation of pulmonary veins. Methods: We assessed 28 consecutive patients (24 male, aged 534-2.4 years) with normal left ventricular (LV) ejection fraction (EF) referred for catheter ablation. Patients undertook standard echocardiographic and TD measurements at the lateral and septal mitral annulus at baseline and 24 hours post ablation. LAEF estimated from LA volumes (apical 2 and 4 chamber) was given as the ratio of maximal minimum LA volume/maximal LA volume and used as surrogate of LA function. Table 1. Comparison between Control and Baseline Afib Groups. and AFib Group at Baseline and after Ablation LA diameter HR LAEF Transmitral A (ram) (bpm) (cm/s) Control 35.2-}-3.8 63.7±9.4 0.53-}-0.06 0.39±0.08 AFib Baseline 41,1±7.0" 58,5±14.1 0 . 4 7 ± 0 . 1 " 56.3±14.8" AFib Post Ablation 4 1 , 4 ± 6 . 4 70,5±14.9"* 0.39±0.08** 50,1±15.0"* Diastolic volume Systolic volu me Septal Lateral Am (ml) (ml) (cm/s) (cm/s) Control 41.6±12.2 20.4±2.7 9.9±1.3 10.2±2.6 AFib Baseline 53,8±18.8" 30,1 ±16.2* 7,9±2.4 * 8.1 ±2.6* AFib Post Ablation 55.1 ±20.4 34,8±15.7** 6,8±1.9** 7.6±2.5 • p < 0.05 compared to control; **p< 0.05 compared to Afib baseline. A control group with 23 subjects of similar age (52.1 4-2.6 years) and sex (15 male) was assessed. Results: At baseline, heart rate and LVEF was similar for Afib and control. LAEF was lower for AFib group compared to control while LA diameters and volumes were increased. Transmitral A and TD Am velocities were lower for Afib group. A moderate correlation was found between LAEF and septal (r= 0.63) and lateral (r = 0.57) Am wave, but not for transmitral A wave. After ablation, a decrease in LAEF was seen together with an increase in systolic LA volume. Am septal velocities decreased, with a modest correlation between the percent of change in LAEF and septal Am (r=0.44). Though transmitral A wave decreased after ablation, it showed no correlation with LAEE The acute decrease in LAEF did not correlate with the number of RF pulses or clinical variables. Conclusion: Patients with paroxysmal Afib show a decrease in LA function that is not correlated to LA size. Shortly after ablation, there is a further impairment in LA function that can be adequately estimated by TD Am velocities 297 Echocardiographic evaluation of left atrial mechanical function in patients with paroxysmal atrial fibrillation N. Fukuda, H. Shinohara, K. Sakabe, K. Wakayama, Y. Tamura. NationalZentsuji Hospital, Department of Clinical Research, Zentsuji Ci~ Japan Aim: Left atrial (LA) mechanical function was evaluated in patients with paroxysmal atrial fibrillation (PAr) using conventional and tissue Doppler echocardiography. Methods: Studied subjects were 55 consecutive patients, aged over 55 years (mean 70±10 years), with PAr episode detected by standard or Holter ECG recording. Significant valvular disease, myocardial disease, and left ventricular (LV) systolic dysfunction were excluded. 20 healthy elders (73-1-8 years) (N group) and 24 chronic nonvalvular AF (744-8 years) (AF group) were served as controls. Percent change of LA diameter (LAD) during cardiac cycle (%LADC), derived from (maximum L A D minimum LAD)/maximum LADxl00, obtained from M-mode echocardiography, was an index of LA function. The PAf patients were divided into 33 patients with preserved LA function (preserved PAr group) and 22 with impaired LA function (deteriorated PAr group) based on mean value minus 2SD of %LADC (17%) in the N group. The LA volume (LAV) and %LADC were compared among PAr, N, and AF groups. Atrial systolic velocities of mitral inflow (A), pulmonary venous flow (Ar), and mitral annulus (Aa) were compared between preserved and deteriorated PAr groups. 39 patients of the PAr group were followed during 234-1 5 months. Results: (1) LAV was larger in the AF group (1494-38ml), deteriorated PAF group (129±25ml), preserved PAr group (95+23ml) than in the N group (794-16ml)(p<0.05). %LADC was smaller in the the AF group (94-2%), deteriorated PAr group (134-2%), preserved PAr group (214-4%) than in the N group (234-3%) (p<0.05). No significant difference was found in the left ventricular volume and ejection fraction among 4 groups. (2) The A, Ar, and Aa were smaller (p<0.05) in the deteriorated PAr group than in the preserved PAr group (A: 75+17 vs 61 ±20cm/s, Ar: 2918 vs 21 ieom/s, Aa: 11 d_3 vs 7i2cm/s). (3) Chronic AF was developed significantly often (p<0.01) in the deteriorated PAr group [11/17 (65%)] than in the preserved PAr group [1/22 (5%)] during follow-up period by KaplanMeier analysis. Conclusion: These results suggest that the LA function in patients with PAr may be impaired, and that the degree of LA dysfunction may associate with the risk of chronic AF. 298 Atrial strain and strain rate; a novel method for the evaluation of atrial stunning S. Binici 1 , H. Ozkan 2, E. Tenekecioglu 2, MC. Basel 2, S. Akdemir 2, H. Ari 2, T. Bozat 2 , V. Koca 2 . 1 Bursa Yuksek Ihtisas Hospital Cardiology, Bursa, Turkey; 2Bursa Yuksek Ihtisas Hospital, Cardiology, Bursa, Turkey We studied 45 patients who had atrial fibrillation(AF) was defined group I and compared with group II in which consisted 35 patients. Left atrial systolic strain (LAe), left atrial peak systolic strain rate (LAsSR), interatrial septum systolic strain (SEPe), interatrial septum peak systolic strain rate (SEPsSR), right atrial systolic strain (RAe) and right atrial peak systolic strain rate (RAsSR) were calculated at the 1st, 24th hour and 1st month after the restoration of sinus rhytm (SR)in group I and compared with group I1. LAe, LAsSR, SEPe, SEPsSR, RAe and RAsSR were significantly lower in group I at the 1st, 24th hour of the restoration of SR, but no difference was found end of the 1st month. Patients whose AF persists less than 1 year was defined as group A and those with more than 1 year defined as group B. Any difference was not found between two groups at the 1st, 24th hour, but LAe (6.38±0.45 vs.