Left Atrium Function In Patients Research Articles

Cardiac magnetic resonance analysis of left atrium function in patients with pre-apical hypertrophic cardiomyopathy.

Patients presenting with unexplained T wave inversion on electrocardiogram combined with thickened left ventricular apex but less than 15 mm had been proposed as a preclinical scope of apical hypertrophy cardiomyopathy (pre-ApHCM). However, analysis of left atrial (LA) function in these patients has not been studied. This study aims to evaluate the LA function in pre-ApHCM patients and compare it with patients with ApHCM using cardiac magnetic resonance (CMR) imaging. In this retrospective case-control study, a total of 3,593 CMR reports from Beijing Anzhen Hospital, Capital Medical University, China were reviewed. Finally, 31 pre-ApHCM patients were identified and 40 ApHCM and 31 normal controls were included for comparison. LA volumetric and strain were analyzed by CMR. Two-tailed one-way ANOVA was used to analyze the difference of three groups. Pearson correlation test was used for correlation analysis. All of the volumetric parameters in pre-ApHCM group were higher than those in control group. LA reservoir (LA total EF, εs) and conduit function (LA passive EF, εe) parameters, were significantly different among the three groups, which were the lowest in the ApHCM group, intermediate in the pre-ApHCM group, and the highest in the control group ((all P<0.001). Compared with the control group, the LA booster pump function, both the booster EF and booster pump strain (εa) in ApHCM were impaired (P=0.003 and P=0.002 respectively). Meanwhile, only the εa was impaired (P=0.016) while LA booster EF was not (P=0.064) in the pre-ApHCM group, neither εa nor the booster EF show difference between the ApHCM and pre-ApHCM (P=0.272 and P=0.518 respectively). LA function features in pre-ApHCM patients were similar to ApHCM but different from the normal controls. In pre-ApHCM and ApHCM patients, LA reservoir and conduit function impaired earlier before left atrium enlarged and decreased progressively as apex thickens. These findings may help to understand the LA functional change from pre-ApHCM to ApHCM, and to detect subclinical changes in patients with pre-ApHCM before overt hypertrophy or clinical symptoms develop.

Use of left atrial automated functional myocardial imaging to identify patients with paroxysmal atrial fibrillation at high risk of stroke.

Left atrial automated functional myocardial imaging (AFILA) is a new software program for analyzing the structure and function of the left atrium (LA). The present study sought to analyze the correlation between the LA function parameters as measured by AFILA echocardiography and the risk of cerebral ischemic stroke (CIS) in patients with non-valvular paroxysmal atrial fibrillation (NVPAF) to explore the diagnostic value of LA strain in patients with congestive heart failure, hypertension, age of ≥75 years (doubled), diabetes mellitus, stroke or transient ischemic attack (TIA) (doubled), age of 65-74 years, and sex category (female) (CHA2DS2-VASc) scores of <2. A total of 205 patients with NVPAF were included in the study and divided into the no-CIS group (154 patients) and the CIS group (51 patients). The baseline clinical data for the 2 groups were analyzed, and routine echocardiography examinations were performed. AFILA was used to evaluate the LA function of all the patients. Compared to the no-CIS group, the LA emptying fraction and the LA reservoir strain were decreased, the LA contractile strain (S_CT) was increased, and the S_CT value changed from negative to positive in the CIS group, and the difference between the 2 groups were statistically significant (P<0.001). However, there were no significant differences in the volume at the onset of LA contraction, LA evacuation volume, LA minimum volume, LA maximum volume, and LA conduit strain between the 2 groups. The multifactorial regression analysis showed that age, hypertension, and the S_CT were independently associated risk factors for patients with CIS. After correcting for the clinical factors included in the CHA2DS2-VASc score, the S_CT was shown to predict to NVPAF with stroke [odds ratio (OR): 1.234, 95% confidence interval (CI): 1.101-1.383, P=0.000]. In addition, we included the CHA2DS2-VASc score (instead of age, diabetes, coronary artery disease, and hypertension) in a multiple regression analysis, and found that the S_CT was still significant (OR: 1.252, 95% CI: 1.118-1.402, P=0.000). The difference between the 2 groups in the CHA2DS2-VASc score for the S_CT was statistically significant, especially when the CHA2DS2-VASc score was <2. The S_CT equaled -4.5% was the cut-off value for the presence or absence of CIS in the NVPAF patients, with an area under the curve (AUC) of 0.866, sensitivity of 0.80, and specificity of 0.75 (P<0.0001). Comparison with LA volume parameter, measuring LA strain by AFILA provides a better index for the dynamic assessment of impaired LA function in patients with NVPAF combined with CIS, especially in those with a CHA2DS2-VASc score of <2. In addition, a LA S_CT of >-4.5% is a valuable cut-off for patients with NVPAF. The results of the current study may form the basis for a large prospective multicenter interventional study in which patients with impaired LA S_CT are randomized to receive oral anti-coagulant (OAC) therapy or no OAC therapy for the primary prevention of stroke.

Left Atrial Velocity Vector Imaging Can Assess Early Diastolic Dysfunction in Left Ventricular Hypertrophy and Hypertrophic Cardiomyopathy

The function of left atrium (LA) is difficult to assess because of its ventricle-dependent, dynamic movement. The aim of this study was to assess LA function using velocity vector imaging (VVI) and compare LA function in patients with hypertrophic cardiomyopathy (HCMP) and left ventricular hypertrophy (LVH) with normal controls. Fourteen patients with HCMP (72% male, mean age of 52.6 ± 9.8), 15 hypertensive patients with LVH (88% male, mean age of 54.0 ± 15.3), and 10 age-matched controls (83% male, mean age of 50.0 ± 4.6) were prospectively studied. Echocardiographic images of the LA were analyzed with VVI, and strain rate (SR) was compared among the 3 groups. The e' velocity (7.7 ± 1.1; 5.1 ± 0.8; 4.5 ± 1.3 cm/sec, p = 0.013), E/e' (6.8 ± 1.6; 12.4 ± 3.3; 14.7 ± 4.2, p = 0.035), and late diastolic SR at mid LA (-1.65 ± 0.51; -0.97 ± 0.55; -0.82 ± 0.32, p = 0.002) were significantly different among the groups (normal; LVH; HCMP, respectively). The e' velocity, E/e', and late diastolic SR at mid LA were significantly different between normal and LVH (p = 0.001; 0.022; 0.018), whereas LA size was similar between normal and LVH (p = 0.592). The mean late diastolic peak SR of mid LA was significantly correlated with indices of diastolic function (E/e', e', and LA size). The SR is a useful tool for detailed evaluation of LA function, especially early dysfunction of LA in groups with normal LA size.

Left atrial strain measured by 4D Auto LAQ echocardiography is significantly correlated with high risk of thromboembolism in patients with non-valvular atrial fibrillation.

The 4-dimensional automated left atrial quantification (4D Auto LAQ) tool is a new software for analysis of the structure and function of the left atrium (LA). This study aimed to evaluate the relationship between LA strain (LAS) as measured by 4D Auto LAQ echocardiography and thromboembolism risk in patients with non-valvular atrial fibrillation (NVAF). Eight-five patients with NVAF were recruited from the cardiovascular center of our hospital, including 39 patients at high risk and 46 patients at low risk of thromboembolism. The study participants were assessed by routine echocardiography; 4D images were obtained, after which 4D Auto LAQ assessment was performed. In the thromboembolism high-risk group, the rates of impaired LA reservoir strain, LA contraction strain, LA reservoir circumferential strain, LA conduit circumferential strain, and LA contraction circumferential strain were found to be significantly higher than in the low-risk group. However, there was no significant difference in volume at onset of LA contraction or LA ejection fraction (LAEF) between the 2 groups. LA contraction circumferential strain was found to be an independent high risk factor for thromboembolism [odds ratio (OR): 2.52; P=0.008]. LA contraction circumferential strain >-4.5% was the cut-off for differentiating between participants with high and low risk of thromboembolism, with an area under the curve (AUC) of 0.95 (P<0.0001), a sensitivity of 0.872, and a specificity of 0.978. Sequential analysis revealed that LA contraction circumferential strain had a high diagnostic efficacy for stroke, as well as a specified accuracy in the diagnosis of hypertension and diabetes in patients aged ≥65 years old. However, it was not found to be effective in the diagnosis of heart failure and vascular diseases. LAS is a useful index for the dynamic evaluation of LA function in patients with non-valvular AF, with higher sensitivity and accuracy than LA volume. LA contraction circumferential strain is an independent high risk factor for thromboembolism, and LA contraction circumferential strain >-4.5% is a valuable cut-off to guide the use of anticoagulant therapy in patients with non-valvular AF.

P664 Relationship of left atrial function assessed by 2D speckle tracking echocardiography with left ventricular systolic function in patients with degenerative mitral regurgitation

Abstract Funding Acknowledgements none Background In degenerative mitral regurgitation (DMR), left ventricle (LV) and left atrium (LA) undergo progressive volume overload leading to chamber remodelling and dysfunction in advanced stages. Speckle tracking echocardiography (STE) is an estabilished technique able in detecting subclinical LA and LV dysfunction in this setting. However data are lacking on the relationship of LA and LV function in DMR patients. Purpose Our aim was to assess LA function in patients with DMR and to explore its possible correlations with LV dimensions and systolic function. Methods We enrolled 95 patients with mild to severe DMR, dichotomizing them on the basis of mitral regurgitation severity (DMR 1-2: mild and mild-to-moderate MR; DMR 3-4: at least moderate to severe MR). LA function was assesed with 2D speckle tracking echocardiography. Results The two groups were well matched. DMR 3-4 group (n= 48) showed higher LA and LV volumes, lower right ventricle longitudinal systolic function and higher values of systolic pulmonary pressure. There was not significant difference in LV ejection fraction (LVEF) and global longitudinal strain (GLS). Among LA function indexes, only peak systolic reservoir strain was significantly reduced in DMR 3-4 group (21,9± 6,2% vs 24,7± 7,2% ; p= 0,04). Then population study was further divided in two groups according to the presence (LA dys+) or absence (LA dys-) of LA dysfunction, defined as reservoir strain values below the median [median 23.7%; LAdys- group (n. 49), LAdys+ group (n.46) ]. At the comparison of continuous variables (Tab.1), LAdys+ group showed larger LV end systolic diameter and more impaired LVEF (60,9± 9,8% vs 65,4± 4,8%; p: 0,004) and GLS (20,04 ± 3,7% vs 23,53 ± 2,7%; p &amp;lt;0,001). Conclusions Our data showed that LA reservoir strain was impaired in patients with moderate to severe DMR. Furthermore, patients with LA dysfunction showed reduced LVEF and GLS values. Consequently, LA dysfunction assessed with STE may be a novel marker of early LV systolic dysfunction in patients with degenerative mitral regurgitation. Tab.1 LAdysf- (n = 49) LAdysf+ (n = 46) P value LVESD (mm) 31.78 ± 4.1 34.74 ± 7.6 0.020 LAVI (mL/mq) 44.5 ± 15.1 55.6 ± 25.6 0.015 TAPSE (mm) 26.30 ± 3.96 24.02 ± 3.31 0.004 sPAP (mmHg) 31.4 ± 7.0 36.4 ± 10.9 0.009 LVEF (%) 65.4 ± 4.8 60.9 ± 9.8 0.004 GLS (%) 23.5 ± 2.7 20.0 ± 3.7 &amp;lt;0.001 Comparison of continuous variables between patients with and without LA dysfunction.

TEMPORAL TRENDS IN LEFT ATRIAL FUNCTION IN PATIENTS WITH FABRY DISEASE

Fabry disease is a lysosomal storage disorder that results in deposition of glycolipids in various tissues including the left atrium (LA). Reduced LA function in patients with Fabry disease may represent an early sign of disease progression prior to the development of left ventricular hypertrophy (LVH). However, long-term trends in LA function over time and the temporal relationship between LA function and LVH have not been previously described. We retrospectively assessed the trends in LA function—measured by the LA emptying fraction (LAEF)—in 15 patients with Fabry disease followed at a tertiary care clinic who underwent annual surveillance echocardiography over a 10-year period. Trends were analyzed by linear regression and the estimated LAEF at the beginning and end of the study period were compared to reference standards from a normal healthy population. Patients with reduced LAEF were compared to those with preserved LAEF with respect to clinical and echo characteristics.Of the 15 patients included in the study, 10 (67%) were female and the median age was 42 years (range 26-65 years). Thirteen patients (87%) received enzyme replacement therapy (ERT): 10 (67%) initiated therapy within one year of the first echo. LVH was found in nine patients (60%) on the first echo and 11 patients (73%) on the final echo. LAEF was reduced in five patients (33%): one improved from reduced to normal, two remained reduced, and two progressed from normal to reduced. Notably, reduced LAEF was only found in patients with established LVH who were receiving ERT. Reduced LA function occurred in one-third of patients with Fabry disease in our cohort and was limited to patients who already developed LVH and were receiving ERT. Our findings suggest that LVH, rather than an inherent atrial myopathy, is the predominant cause of LA impairment in patients with Fabry disease.

P5432Invasive assessment by atrial volume-pressure loops of the acute changes in left atrial function induced by pulmonary vein antral isolation

Abstract Background Atrial volume-pressure loops are considered the best method to assess left atrium (LA) function. Changes in atrial function induced by pulmonary vein (PV) antral isolation of atrial fibrillation (AF) have not been documented thus far using this approach. Purpose We aimed to evaluate changes in LA function in patients with paroxysmal atrial fibrillation (PAF) undergoing catheter ablation by atrial volume-pressure loops. Methods Patients undergoing for the first time catheter ablation of PAF by PV antral isolation and PV-LA junction ablation, as clinically indicated, were enrolled from 2 centers. Each center enrolled consecutive patients undergoing PV antral isolation using the same method i.e. radiofrequency or cryoballoon ablation. Patients with severe mitral stenosis or regurgitation, any prosthetic valve, left atrial thrombus or severe systolic or diastolic dysfunction of the left ventricle were excluded. Before and after the procedure, all patients underwent real-time three-dimensional transthoracic echocardiogram to evaluate volume changes of the LA during an entire cardiac cycle, while simultaneously recording LA pressure by a 6F angiographic catheter following transseptal puncture. After the procedure, LA volume and pressure recordings were gated offline by ECG, and were used to plot the LA pressure as a function of LA volume, thus creating a volume-pressure loop. The A loop area is a measure of the booster pump function of the LA. The V loop area expresses the reservoir function of the LA. Pressure and volume data at the clockwise ascending limb of the volume-pressure loop were fitted to the exponential function P = bxea·V, where P = instantaneous LA pressure; V = LA volume; a is the passive elastic chamber stiffness constant (cm–3) that determines the slope of the exponential curve, and b is the elastic constant (mm Hg). Results 34 patients with PAF were analysed, 12 treated with radiofrequency ablation and 22 with cryoablation. The procedure was uneventful in all cases. Mean LA pressure, A-wave amplitude, and V-wave amplitude were all significantly increased post-procedurally (p&lt;0.001 for all). The area of the A-loop decreased (Post: 40.69 ml·mm Hg [IQR 13.7–71.3] vs. Pre: 64.2 ml·mm Hg [IQR 30.9–86.9]; p=0.001), whereas the area of the V-loop increased (Post: 96.5 ml·mm Hg [IQR 45.1–230.5] vs. Pre: 79.2 ml·mm Hg [IQR 46.9–149.7]; p=0.016). Although the elastic constant increased (p&lt;0.001), there was no significant difference in the passive chamber elastic constant (p=0.30). Conclusion Volume-pressure loops can assess procedural changes in LA function. Catheter ablation of AF is associated with a decrease the LA booster pump function of the LA, and in increase in the left atrial reservoir function. Moreover, there is an increase in LA pressures that is observed in the absence of change in LA stiffness.

Assessment of Left Atrial Function in Patients with Non-ST-Segment Elevation Myocardial Infarction Using Two-Dimensional Speckle Tracking Echocardiography

Background: the left atrium (LA) plays a major role in Left ventricular (LV) performance. LA function is a surrogate marker of LV diastolic dysfunction. LA mechanical dysfunction occurs in LV systolic and diastolic dysfunction, coronary artery disease, myocardial infarction (MI), hypertension, aortic stenosis and cardiomyopathies. In the MI process, the contribution of the LA to LV function may increase if the cardiac myocytes are not affected by direct ischemia. However, myocyte necrosis or ischemia of the LA or significant LV systolic/diastolic dysfunction affects this booster effect. Assessment of LA size and function provides prognostic data for the outcome of patients with MI or ischemia. Aim of the Study: was to evaluate LA function in patients with non-ST-segment elevation myocardial infarction (NSTEMI) by two-dimensional speckle tracking echocardiography (2D STE). Patient and Methods: 60 patients with NSTEMI and 20 age-matched normal control individuals were enrolled in this study. Conventional echocardiographic parameters and global longitudinal strain rate (GLSR) were measured at left ventricular (LV) and LA segments. Results: Compared with healthy subjects, patients with NSTEMI had significantly increased LA volumes but significantly decreased LA emptying fraction and GLSR. LA-GLSR had significant correlations with the 2D Doppler echocardiographic parameters of LA function. In particular, global LA peak negative strain rate during early ventricular diastole (LA-GLSRe) was significantly correlated with both LA 2D Doppler echocardiographic parameters and LV contractile function. This could be suggested as a better indicator to evaluate LA function as a preferred parameter of STE. Conclusion: It could be concluded that two-dimensional speckle tracking echocardiography represented a non-invasive, relatively simple and reproducible technique to assess left atrial myocardial function in patients with NSTEMI.

Abstract 15760: Left Atrial Dysfunction in Patients With Anderson - Fabrys Disease Using Magnetic Resonance Imaging Derived Left Atrial Phasic Function

Background: Anderson-Fabrys disease (AFD) is an x-linked lysosomal storage disease caused by deficiency of the enzyme alpha-galactosidase. This results in accumulation of globotriaosylceramide in various organs. The hallmark of cardiac involvement is left ventricular hypertrophy (LVH). However, autopsy studies have demonstrated involvement of the left atrium (LA) as well. There is currently limited data on left atrial volumes and function in patients with AFD. We sought to assess LA phasic volumes and function in patients with AFD using cardiac MRI (CMR) cine data. Method and Results: This was a retrospective study. Consecutive patients with clinically indicated CMR at our center were included. CMR acquired 2 and 4 chamber steady state free precession (SSFP) cine data were used to measure LA volume and phasic function with commercially available off-line software (eSieVVI, Siemens Medical System). We included 37 patients with AFD (18 males, mean age 48±13 yrs) and 22 age balanced healthy volunteers (8 males, mean age of 40±14 yrs). LA maximal and conduit volumes were not different between AFD and controls, but the LA minimal was larger (Table). Volume derived reservoir, conduit, and pump function were significantly reduced in AFD (Table). Strain measured reservoir and pump function were also significantly reduced in AFD. An inverse correlation was seen between LA reservoir strain and left ventricular (LV) mass (r=-0.53) and myocardial late gadolinium enhancement (LGE) measured using the 4 (r=-0.67) and 6 (r=-0.67) standard deviation thresholds. Conclusion: This is the first study to demonstrate abnormal LA function in patients with AFD using both volumetric and strain techniques. Patients with AFD had reduced LA reservoir and pump function with modest correlation with disease severity based on the burden of LV LGE and LV mass. Further studies are needed to assess the relationship between LA function and prognosis including the development of atrial arrhythmia.

Association of left atrial booster-pump function with heart failure symptoms in patients with severe aortic stenosis and preserved left ventricular ejection fraction.

Identification of heart failure (HF) symptoms in patients with severe aortic stenosis (AS) and preserved left ventricular (LV) ejection fraction (EF) is clinically important, but assessment of HF symptoms is challenging. It was recently reported that resting left atrium (LA) functions are related to exercise performance and are also important prognostic markers for patients with HF. The aim of this study was to assess the association of the HF symptoms with LA function in patients with severe AS and preserved LVEF. We retrospectively studied 40 patients with severe AS and preserved LVEF (all ≥50%) who were referred for aortic valve replacement (AVR). LA reservoir (SR-LAs), conduit (SR-LAe), and booster-pump (SR-LAa) functions were determined as the averaged global LA speckle tracking longitudinal strain rate from apical four- and two-chamber views. Twenty patients were symptomatic and 20 asymptomatic. Aortic stenosis severity was similar for the 2 groups. Symptomatic status was associated with age, LV mass index, hemoglobin, B-type natriuretic peptide, LV end-systolic volume index, LVEF, LA volume index, SR-LAs, SR-LAe, and SR-LAa. Importantly, multivariate logistic regression analysis revealed that SR-LAa was the only independent determinant of symptomatic status (OR=0.242, P=0.002). Furthermore, significant improvement of SR-LAa was observed along with the reduction in LA volume index and LV mass index after AVR. SR-LAa was found to be associated with the HF symptoms. Characterization of LA booster-pump function may be useful for the assessment of the symptomatic status in patients with severe AS patients and limited physical activity.

Left atrium function in patients with coronary artery disease.

The left atrial cavity has recently been identified as a potential biomarker for cardiac and cerebrovascular accidents. This review examines the potential of left atrial size and function in predicting cardiovascular disease in the general population and outcomes in coronary artery disease (CAD) patients. The atrium is perfused primarily by branches of the proximal left circumflex coronary artery (LCx), and depression of the cavity mechanical performance has been demonstrated in experimental studies during LCx occlusion. Thus, left atrial volume and function assessment may have prognostic relevance, particularly in CAD patients. Such a line of thinking, however, is challenged by the widespread notion that the contribution by left atrial chamber morphology and functional quantitation to the risk stratification process after a first cardiovascular event is not adequately considered. However, a number of studies have shown that left atrial volume predicts survival and major adverse events after an acute myocardial infarction. Left atrial remodeling also provides an important overall prognostic information and correlates with brain natriuretic peptide after primary percutaneous coronary interventions. Evaluation of left atrial size and function is currently of great interest and it will be more so in the very near future, given its potential for insights into the pathophysiology of the ischemic heart, which makes it an important clinical risk identifier in CAD patients.

Comparison of Left Atrial Function between Hypertensive Patients with Normal Atrial Size and Normotensive Subjects Using Strain Rate Imaging Technique

Background: Patients with hypertension are at risk of structural and functional changes in the left atrium (LA). There are only a few studies on the impact of hypertension on LA function, especially in hypertensive patients with a normal LA size. We, therefore, designed this study to evaluate LA function in patients with a normal LA size via deformation imaging. Objectives: We assessed regional longitudinal strain rate imaging (SRI) profiles along with tissue velocity imaging (TVI) in the LA walls to quantify LA reservoir function and explore changes in LA function in hypertensive patients with a normal value of LA size. Patients and Methods: One hundred twenty-four subjects with normal angiography (mean age = 56.28 ± 8.91 years, 46% male), who were referred to the Echocardiography Laboratory of our institution, were enrolled in this study. These subjects were categorized into two groups: hypertensive (75 cases) and age-matched normotensive (49 cases) groups. All the cases of the patient and control groups had a normal LA size. SRI parameters included strain (ST, %) and strain rate (SR, s -1 ), and tissue imaging parameters such as peak systolic velocity (Sm, m/s) were measured in four septal, lateral, anterior, and inferior LA walls at the mid-level. Results: Compared with the controls, the patients with a history of hypertension showed significantly lower values of Sm, ST, and SR in each segment of the LA. There was no effect of age on these indices. Also, no differences regarding Sm, ST, and SR were found between the septal, lateral, anterior, and inferior LA walls in each group. By multivariate linear regression analysis, a history of hypertension was the only independent determinant of average LA strain rate in the all the individuals (P < 0.001). When this analysis was repeated in the patients with a history of hypertension, the only independent determinant of average LA strain rate was heart rate (P = 0.026). Conclusions: In our subjects, with a normal value of LA size, the effect of hypertension on LA reservoir function was independent of age, sex, heart rate, left ventricular mass index, and left ventricular ejection fraction. Additionally, heart rate independently correlated with reduced TVI and SRI parameters in the patients with hypertension.

Left atrial volume and function in patients following ST elevation myocardial infarction and the association with clinical outcome: a cardiovascular magnetic resonance study

The left atrium (LA) transfers blood to the left ventricle in a complex manner. LA function is characterized by passive emptying (LA passive fraction), active emptying (LA ejection fraction), and total emptying (LA fractional change). Despite this complexity, the clinical relevance of the LA is based almost exclusively on LA maximal volume (LAmax), which may not glean the full prognostic potential. Cardiovascular magnetic resonance (CMR) is considered the most accurate method for studying LA function and size. The aim of the present study was to evaluate the prognostic importance of LA function in patients following ST elevation myocardial infarction (STEMI). In 199 patients, a CMR scan was performed within 1-3 days after STEMI to measure LAmax and minimal volume (LAmin) and LA function. The incidence of death, re-infarction, stroke, and admission for heart failure [major adverse cardiac event (MACE)] were registered during the follow-up period [2.3 years (inter-quartile range: 2.0-2.5)]. A total of 40 patients (20%) met the clinical endpoint of MACE during follow-up. In a Cox regression analysis adjusting for known risk factors, LA fractional change remained independently associated with MACE [adjusted hazard ratio: 0.66 (95% confidence interval: 0.46-0.95)]. LAmax, LAmin, or LA passive fraction was not independently associated with MACE. Furthermore, LA fractional change provided incremental prognostic value to LAmax and other known predictors (Wald χ(2) 31.0 vs. 39.9, P= 0.016). In STEMI patients, impaired LA fractional change is independently associated with outcome and provide incremental prognostic information to established predictors including LAmax.

Impact of reduced left atrial functions on diagnosis of paroxysmal atrial fibrillation: Results from analysis of time-left atrial volume curve determined by two-dimensional speckle tracking

Atrial fibrillation is commonly associated with impaired reservoir and booster functions of the left atrium (LA). Recent advances in two-dimensional speckle tracking technique (2DST) enabled automatic analysis of the time-LA volume curve representing these functions. Our objective was to evaluate LA function in patients with or without paroxysmal atrial fibrillation (PAF) using 2DST. We studied 111 patients (68 men, age 62 ± 16 years) with (n = 53) or without (n = 58) PAF. After constructing time-LA volume curves from the apical four and two chamber views (iE33, Philips with QLAB 6.0, Philips Medical Systems, Bothell, WA, USA), maximal LA volume (LAVmax), preatrial contraction LA volume (LAVpreA), and minimum LA volume (LAVmin) were obtained. Then, LA reservoir volume (ARV=LAVmax-LAVmin) and active emptying volume (AEV=LAVpreA-LAVmin) were calculated to determine ARV/LAVmax as reservoir function and AEV/LAVpreA as booster pump function. PAF was associated with greater LAVmax than that in controls (80 ± 21 ml versus 65 ± 16 ml, p < 0.001) and with reduced reservoir and booster functions (ARV/LAVmax 46 ± 9% versus 52 ± 7%; AEV/LAVpreA 29 ± 10% versus 36 ± 6%, p < 0.001). Multivariate logistic analysis demonstrated that ARV/LAVmax and AEV/LAVpreA were closely associated with the existence of PAF. These results demonstrate that the present 2DST enables determining LA reservoir and booster functions, providing insights into the diagnosis of PAF.

E0547 Left atrium function in patients with paroxysmal atrial fibrillation: analysis from two-dimensional speckle tracking echocardiography

IntroductionTo observe the changes of left atrium function in patients with paroxysmal atrial fibrillation (AF) using two-dimensional (2D) speckle tracking echocardiography (STE).MethodsThe study population consisted of 33 patients with paroxysmal...

459 Remodelling vs restrictive ring annuloplasty in severe mitral regurgitationand left ventricular dysfuntion

) and 41.2±9.9 mm Hg, respectively. It was determined that the IVV (0.11±0.03 cm/s vs 0.15±0.02 cm/s, p<0.001) and the IVA (2.3±0.7 m/s 2 vs 2.9±0.4 m/s 2 , p<0.001) of the RV was significantly lower and the right ventricular MPI increased (0.60 ± 0.2 vs 0.28 ± 0.06, p<0.001 ) in pa- tients with MS. It was also demonstrated that the MVA, left atrial diameter, mean diastolic gradient, and PAP were strongly correlated with IVA (r=-0.71 (p<0.001), r=0.42 (p=0.003), r=-0.55 (p<0.001), and r=-0.51 (p<0.001), respectively). Additionally the correlation between right ven- tricular IVA and MPI (r=-0.78 (p<0.001)) was significant. Systolic move- ment of the tricuspid annulus, Pat and FS were not sensitive in detecting the severity of the MS. Conclusion: This study demonstrate that the tissue Doppler systolic pa- rameters of right ventricular IVA is an important marker to assess the severity of mitral stenosis in patients with rheumatic valve diseases. A. O. Monaldi, Cardiology Dept., Naples, Italy Background: Mitral stenosis (MS) causes left atrium (LA) enlargement and dysfunction, resulting in reduced LA flow velocity. Tissue Doppler imaging (TDI) assesses regional myocardial function noninvasively; particularly Strain Rate (SR) imaging enables quantitative measurement of atrial reservoir func- tion. Aim of the study: To evaluate the effect of MS on right and left atrial (LA/RA) reservoir function using Strain(S) and SR and to compare atrial myocardial deformation properties in MS patients with sinus rhythm and in those with atrial fibrillation (AF). Methods: We studied 85 subjects: 33 (28 F, 5 M) healthy subjects (52 years) and 52 patients with isolated mitral stenosis: 16 with chronic AF and 36 in sinus rhythm, without CAD, hypertension, diabetes mellitus, left ventricular (LV) dysfunction (EF<50%), LV dilatation, LV hypertro- phy or other valvular disease. By Echocardiography System Seven GE equipped with TVI function were measured: mitral valve area in 2D and with PHT, mean mitral valve gradient, Wilkins' scores, LA/RA Volume (maximum and minimal), LA/RA EF (%), right ventricule systolic pres- sure, LA diameters. Peak systolic tissue atrial S and SR were evaluated in apical 4 and 2 chambers view at the level of the mid segment of the septal, lateral, anterior and inferior atrial walls, and at the mid segment of the RA free wall. Results: MS patients had significantly larger LA dimension and signifi- cantly lower LA ejection fraction than controls. LA EF in patients with MS (media 28.32%) was lower than LA EF in controls (44.35%) and LA maxi- mal volume was greater in patients with MS (97.63 mL) in comparison with controls (24.51 mL). The myocardial atrial S and SR were found to be significantly (p<0.01) lower for each atrial wall in patients with pure MS compared to controls (46±15 vs 75±18%). Patients with AF + MS showed significant (p<0.01) more compromised atrial myocardial deformation properties than MS patients in sinus rhythm (25±10 vs 55±18%). A sig- nificant correlation was found between left atrial S and mitral valve area (p=0.03; R=-0.51) and between atrial S and mean gradient (p=0.005; R=-0.63) accross the mitral valve. Conclusion: Strain Imaging is an echocardiography technique useful to study ass esment of LA function in patients with MS noninvasively. Atrial myocardial deformation properties are compromised in patients with MS; this impairment is more pronounced in patients with MS + AF.

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<h3>Introduction</h3> To observe the changes of left atrium function in patients with paroxysmal atrial fibrillation (AF) using two-dimensional (2D) speckle tracking echocardiography (STE). <h3>Methods</h3> The study population consisted of 33 patients with paroxysmal atrial fibrillation and 30 age, sex-matched control subjects in sinus rhythm (SR) who were referred to our echocardiography laboratory. All of the patients were in sinus rhythm when they were checked. Left atrial diameter (LAD), left atrial area (LAA), interventricular septum thickness (IVST); Left ventricular end-diastolic diameter (LVEDD) were measured in 2-dimensional echocardiography imaging. LV ejection fraction was determined. Measured mitral valve A wave velocity time integral (VTI-A) and maximum velocity (VA). LA wall strain in the longitudinal direction obtained using 2DSTE. Measured peak atrial longitudinal strain (PALS) and atrial contraction longitudinal strain (ACLS) in apical 4-chamber view and apical 2- chamber view. Measured time to peak longitudinal strain (TPLS). ∆\TPLS was defined as the difference between the TPLS in apical 4-chamber view and apical 2- chamber view. <h3>Results</h3> There were no significant differences between the 2 groups regarding age (63±12 vs 60±9 years), sex (males 48% vs 60%) and history of hypertension and diabetes mellitus. Compared with control group, ∆-TPLS were significantly increased in AF group (52.83±32.2 vs 31.33±20.2, p&lt;0.05). In Patients with AF, ACLS were significantly decreased than in control group (10.09±3.3 vs 13.74±3.1 p&lt;0.05). The PALS; LAD; LVEDD; IVS; EF; VA; VTI-A and LAA between paroxysmal AF and control group did not show statisticant difference (p&gt;0.05). <h3>Conclusions</h3> 2DSTE can effectively and easily measure LA ∆-TPLS and ACLS, speckle tracking echocardiography could be a method to non-invasively assess LA function in paroxysmal atrial fibrillation patients.