Biplane Area-length Method Research Articles

Comparison of determinations of left atrial volume by the biplane area-length and Simpson's methods using 64-slice computed tomography

There is increasing evidence that left atrial (LA) size is an important predictor of adverse cardiovascular outcomes such as atrial fibrillation, stroke, and congestive heart failure. The aim of this study was to determine whether there is a difference in results of quantification of LA volume by the area-length and Simpson's methods using multislice computed tomography (MSCT). The study population consisted of 51 patients with sinus rhythm (sinus group) and 20 patients with atrial fibrillation (af group) clinically indicated for MSCT angiography for evaluation of coronary arteries. Maximum LA volume, obtained at end-systole from the phase immediately preceding mitral valve opening, was measured using the area-length and Simpson's methods. In the sinus group, the mean LA volumes, indexed to body surface area, were 48.4+/-17.9 ml/m(2) with the area-length method and 48.3+/-17.0 ml/m(2) with the Simpson's method. In the af group, the mean indexed LA volumes with the area-length method and the Simposon's method were 91.5+/-47.5 ml/m(2) and 90.3+/-45.9 ml/m(2), respectively. LA volumes calculated by the area-length method exhibited a strong linear relationship and agreement with those calculated using Simpson's method in both the groups (sinus group: r=0.99, P<0.0001, af group: r=0.99, P<0.0001). The area-length method is a simple and reproducible means of assessment of LA volume. Standardization of LA volume assessment using MSCT is important for serial follow-up and meaningful communication of results of testing among institutions and physicians.

Increased Left Atrial Volume Index: Potent Biomarker for First-Ever Ischemic Stroke

To establish the incidence and correlation of increased left atrial volume index (LAVI) in patients with first-ever ischemic stroke. Using our institution's epidemiological database, we defined a cohort of 432 patients (cases) who underwent transthoracic echocardiography within 60 days of first ischemic stroke between January 1, 1985, and December 31, 1994. Left atrial volume was measured with the biplane area-length method, indexed to body surface area (LAVI, expressed as mL/m(2)). The control group consisted of 416 community residents who underwent transthoracic echocardiography as participants in a stroke risk factor study. Increased LAVI was defined as 28 mL/m(2) or higher. Survival in patients was compared with expected survival among white Minnesotans and was further modeled as a function of age, sex, LAVI, and clinical risk factors. Among the included 306 patients, 230 (75%) had increased LAVI (mean+/-SD, 49+/-21 mL/m(2)). Patients with increased LAVI were older than those with normal LAVI (mean+/-SD age, 76+/-11 vs 71+/-13 years; P=.003) and had more cardiovascular risk factors (mean+/-SD number, 1.8+/-0.07 vs 1.3+/-0.89; P<.001). Mean LAVI was higher in cases than in age- and sex-matched controls (P<.001). At 5-year follow-up, cases showed excess mortality compared with age-matched controls (P=.001). After variables were adjusted for age, sex, and clinical risk factors, LAVI was independently associated with mortality. A useful index for prediction of adverse cardiovascular events, LAVI might also predict first ischemic stroke and subsequent mortality.

Two-Dimensional Estimation of Left and Right Ventricular Size and Function—Comparison with Cardiac Magnetic Resonance Imaging Volumetric Analysis

usual management-including serial cardiac biomarkers and either exercise stress testing or myocardial perfusion scanning (if biomarkers were negative). Invasive coronary angiography was performed if either biomarkers or functional study were abnormal. Results: 50 patients (mean age 58.2 years, 32 male) were assessed. 3/50were reclassified as high risk acute coronary syndrome (ACS) with positive Troponin I measured at 6 h. 47/50hadanon-cardiac causeof chest painor low riskACS as a final diagnosis. Of the three cases with high risk ACS, CTCA demonstrated one had obstructive disease (>70% stenosis), onehadmoderate disease (50–70%stenosis) and one hadmild disease (<50% stenosis). These findingswere confirmed by invasive angiography. Of those with noncardiac chest pain or low risk ACS 15/47 had no disease, 28/47 had mild disease, 3/47 had moderate disease and 1/47 had obstructive disease on CTCA. Conclusions: Dual source CTCA is useful in the assessment of patients with intermediate risk acute chest pain. CT coronary angiography showed good correlation with invasive angiographic findings in those with high risk ACS. In those with non-cardiac diagnosis or low risk ACS there is a significant rate of coronary artery disease identified. doi:10.1016/j.hlc.2008.05.136 136 systolic area over the RV end-diastolic area, correlated onlymoderatelywith the volumetric EF (r= 0.75, p< 0.001). In contrast, estimation of LV volumes, mass and EF by biplane area-length method demonstrated excellent correlation to volumetric data (r= 0.89, 0.92 and 0.91, p< 0.001 for all). Conclusion: Two-dimensional estimations of volume and functioncorrelatewellwithLVvolumetric analysis, butnot with RV volumetric analysis. Therefore, estimation of RV size and function based on linear or planimetric assumption models are not reliable, and existing reference values should be interpreted with caution. doi:10.1016/j.hlc.2008.05.137

The Predictive Value of Left Atrial Volume in Patients Referred for Transplant Evaluation

Background: LA volume (LAV) has been shown to entail powerful independent prognostic information in diverse heart failure settings. However, the value of LAV for event prediction has not been assessed in a pre-transplant population yet, neither alone nor in context with validated prognostic markers. Methods: To assess the predictive value of LAV, we collected data on 51 patients (51 ± 13 years, 69% male, 71% white) referred for evaluation for cardiac transplantation from 5/2003 to 4/2005. LAV was calculated offline by the biplane area-length method.

Assessment of Left Atrial Volumes at 1.5 Tesla and 3 Tesla Using FLASH and SSFP Cine Imaging

To investigate left atrial volumes and function and their variability in healthy volunteers using steady state free precession (SSFP) and fast low angle shot (FLASH) sequences at both 1.5 and 3 T using both the short-axis and biplane area-length methods. Ten healthy volunteers underwent CMR at both 1.5 and 3 Tesla. The biplane area-length method utilized volumes from the horizontal and vertical long axis images. There were no significant differences between left atrial short-axis volumes or function between 1.5 and 3 T assessed using either FLASH or SSFP sequences. The biplane area-length method underestimated maximal left atrial volume using FLASH by 12 mL at 3 T (18%) and by 10 mL (14%) at 1.5 T (p = 0.003 and p = 0.05 respectively). Variability was larger for left atrial measurements using the biplane area-length method. Field strength had no effect on left atrial volume and function assessment using either FLASH or SSFP. The use of the short-axis method for the acquisition of left atrial parameters is more reproducible than the biplane area-length for serial measurements.

Evaluation of Left Atrial Size in Patients with Atrial Arrhythmias: Comparison of Standard 2D Versus Real Time 3D Echocardiography

Two-dimensional echocardiography may not correctly indicate size in nonspherical atria. The present study compares different parameters of left atrial size evaluated by standard two-dimensional echocardiography with left atrial volume measured using three-dimensional echocardiography (3DE). One hundred seventy consecutive patients with a history of atrial arrhythmias were studied by standard two-dimensional and by real time 3DE. Of these 166 (98%) recordings were of sufficient quality for interpretation by both imaging techniques. The following parameters of left atrial size were measured: parasternal long axis diameter (PLAX), apical 4-chamber short-axis diameter (4CH short axis), apical 4-chamber (4CH long axis), and 2-chamber long-axis diameters and planimetry areas. Two-dimensional-derived left atrial volumes were calculated by using both single plane (4CH area-length) and biplane area-length methods. The 2D parameters were then correlated with left atrial volume measured by 3D echocardiography. Linear regression analysis showed moderate correlation for 4-chamber planimetry area (r = 0.76, P < 0.0001) and 2D-derived volume calculations (r of 4CH single plane area-length LA volume = 0.74 and biplane area-length LA volume = 0.78, P < 0.0001). Diameters correlated less well with 3DE volume (r of PLAX = 0.67, 4CH short axis = 0.68, 4CH long axis = 0.63, P < 0.0001 respectively). The results demonstrate that measurements of dimensions using standard echocardiography are of limited accuracy to assess left atrial volume. If 3DE is not available, 4-chamber planimetry area is a valid simple parameter for evaluating left atrial size in clinical practice. Two-dimensional-derived volume by biplane area-length method was only slightly better correlated with 3DE volume than 4-chamber planimetry area.

Echocardiographic assessment of left atrial ejection force and kinetic energy in chronic heart failure

There is limited information regarding left atrial (LA) systolic adaptation to chronic heart failure (HF) in humans. Therefore, the aim of our study was to determine the LA ejection force (LAEF) and kinetic energy in patients with HF. 58 HF patients (63.8% in NYHA II) and 48 controls were studied. LA volumes were echocardiographically determined using the biplane area-length method. LA systolic function was assessed with the: (a) active emptying volume (ACTEV) and fraction (ACTEF), (b) ejection force (kdynes/m2), calculated with Manning's method [LAEF = 0.5 * rho * mitral orifice area * A2; rho: blood density, Alpha: late transmitral flow velocity] and a modification incorporating parameters of LA function [LAEFm = 0.5 * rho * LA volume at onset of atrial systole * ACTEF * A2/VTl A], and (c) kinetic energy [LA-ke (kdynes.cm/m2) = 0.5 * rho * ACTEV * A2]. LA maximal volume and ACTEV were lower (42.9 +/- 14.4 vs. 59.7 +/- 14.7 cm3, P < 0.0001; 10.9 +/- 3.3 vs. 13 +/- 3.3 cm3, P = 0.0001, respectively), whereas ACTEF (%) was higher (36.3 +/- 7 vs. 29.3 +/- 7.6 cm3, P < 0.0001) in controls than HF. LAEF, LAEFm, and LA-ke were lower in controls than HF (7.68 +/- 5.1 vs. 10.16 +/- 3.7 kdynes/m2, P = 0.006; 3.63 +/- 2.05 vs. 5.02 +/- 1.74 kdynes/m2, P = 0.0004; 2.41 +/- 1.91 vs. 3.99 +/- 2.1 kdynes.cm/m2, P < 0.0004, respectively). Despite the decreased LA systolic shortening, overall LA systolic performance is augmented in chronic HF due to LA dilation.

Evaluation von zwei „schnellen” Softwareprogrammen zur Bestimmung der linksventrikulären Volumina in der retrospektiv EKG-gegateten Mehrzeilen-Spiral-CT des Schweineherzens: Biplanare Flächen-Längen-Methode und „Shape-tracking”-Methode

Evaluation of 2 "fast" software tools, a biplane area-length method, and a new automatic "shape tracking" method, for the calculation of left ventricle volumes (end-diastolic volume EDV, end-systolic volume ESV, stroke volume SV) and ejection fraction (EF) in retrospectively ECG-gated multidetector computed tomography. 60 contrast-enhanced cardiac CT datasets (16 x 0.75 mm collimation, normal dose: 120-140 kV, 400-500 mAs (eff) [n = 44], low dose 120 kV, 100 mAs (eff) [n = 16]) were acquired from eight intubated healthy pigs on different days. Images were reconstructed with a slice thickness and increment of 2 mm every 10 % of the cardiac cycle. The LV function was evaluated via the common short axis method as the reference method, the biplane area-length method, and the automatic "shape tracking" method. In the latter a three-dimensional triangulated deformable surface model was used to segment the endocardial border of the left ventricle and to track its motion through the cardiac phases. The results were compared using the Bland-Altman-plot, the correlation coefficient, and the Wilcoxon test. All 60 data sets could be evaluated with all three methods. Good correlations were found for left ventricular functional parameters for all data sets, the normal dose (ND), and low dose (LD) data sets between 0.65 and 0.89 for the "shape tracking" method and between 0.7 and 0.87 for the area-length method. The "shape tracking" method showed a mean overestimation of the EDV of 3.1 (LD, p = 0.38) to 4.3 ml (ND, p < 0.05), the SV of 4.0 (LD, p = 0.08) to 4.9 ml (ND, p < 0.05) and the EF of 1.3 (LD, p = 0.16) to 2.0 % (ND, p < 0.05). The EDV was underestimated between 0.3 (LD, p = 0.7) and 1.1 ml (ND, p = 0.08). The area-length method showed an overestimation of the EDV (6.6 to 6.7 ml [p < 0.05]), the SV (5.9 to 8.4 ml [p < 0.05]), the EF (1.2 to 3.0 % [p < 0.05]) and the normal dose ESV (0.6 ml [p = 0.74]). The low dose ESV was underestimated (1.3 ml [p = 0.21]). The left ventricular functional parameters acquired with both "fast" software methods correlate well with the common semi-automatic short axis method, and both methods significantly overestimate the EDV, SV and EF. Both methods can be used in low dose examinations.

Left atrial remodelling in mitral regurgitation--methodologic approach, physiological determinants, and outcome implications: a prospective quantitative Doppler-echocardiographic and electron beam-computed tomographic study

To define accurate and normal range of echocardiographic left atrial (LA) volume measurement and to assess the prevalence, determinants, and outcome implications of LA enlargement in mitral regurgitation (MR). We prospectively compared LA volume obtained simultaneously by electron beam-computed tomography (EBCT) and by four echocardiographic methods in 33 test patients. Accurate echocardiographic LA volume measurements were obtained only by biplane area-length method with vertical longitudinal-length (r = 0.95, P < 0.0001; 145 +/- 57 vs. 143 +/- 55 mL, P = 0.57). Using this method, the normal range in 100 normal subjects, the physiological determinants and outcome implications of LA enlargement in 320 patients with organic MR were analysed. In normal subjects, indexed to body surface area, LA index (27 +/- 6 mL/m(2)) was not influenced by age or gender and values > or = 40 mL/m(2) were beyond the upper limit of normal. In MR, the most powerful determinants of LA enlargement were higher regurgitant volume (RVol) and atrial fibrillation (AF) (P < 0.0001), followed by older age, female gender, higher left ventricular end-systolic volume, and mass (all P < 0.001). After diagnosis in sinus rhythm, LA index > or = 40 mL/m(2) predicted superiorly and independently to LA diameter the occurrence of AF [adjusted RR 1.48 (1.06-2.16), P < 0.01] and the combined endpoint of death or need for mitral surgery [adjusted RR 1.61 (1.3-2.0), P < 0.0001]. LA remodelling can be accurately assessed by echocardiography and LA index > or = 40 mL/m(2) is beyond the normal range. In organic MR, higher LA index is the combined result of multiple physiological effects, provides independent prognostic information, and therefore should be part of a comprehensive echocardiographic examination.

Left Αtrial Remodeling in Patients Younger than 70 Years with Diastolic and Systolic Heart Failure

We sought to determine left atrial (LA) volume and systolic function (LA remodeling) in younger (<70 years) patients with systolic and diastolic heart failure (HF). In all, 32 patients with diastolic HF (left ventricular [LV] ejection fraction > or = 0.50), 26 patients with systolic HF (LV ejection fraction < 0.50), and 48 control subjects were studied. LAlpha volume (cm(3)/m(2)) was echocardiographically determined at mitral valve opening (maximal), mitral valve closure (minimal), and atrial systole (electrocardiographic Rho wave) using the biplane area-length method. The LA active emptying fraction (%) and ejection force (kdyne/m(2)) served as indices of LA systolic function. LA maximal volume was greater in systolic HF than diastolic HF and in the latter greater than control (68.6 +/- 13.8 vs 52 +/- 11.6 vs 42.9 +/- 14.4, respectively, P < .0001). Active emptying fraction was similar between diastolic HF and control, and greater than systolic HF (31.5 +/- 8.1 vs 36.3 +/- 7 vs 26.6 +/- 6.2, respectively, P < .0001), whereas LA ejection force was similar in diastolic and systolic HF and greater than control (5.05 +/- 1.3 vs 4.98 +/- 2.17 vs 3.63 +/- 2.05, respectively, P = .001). Vmax was related to body surface area, brain natriuretic peptide, and LV mass in diastolic HF (multiple R2 = 0.74) and to diastolic blood pressure, LV mass, and early to late transmitral flow velocity ratio in systolic HF (multiple R2 = 0.96). LA remodeling is more severe in systolic HF than diastolic HF and governed by different mechanisms. This may be of significant clinical relevance regarding the morbidity and mortality of these two conditions.

Effect of beta-blocker therapy on left atrial function in patients with heart failure: comparison of metoprolol succinate with carvedilol

We aimed to compare the effects of carvedilol and metoprolol succinate on left atrial (LA) function in patients with chronic heart failure. Thirty three patients (6 females, 27 males) who had not received beta blocker treatment previously and whose left ventricular ejection fraction was below 40% were included in this study. LA volumes were measured echocardiographically just before the time of mitral valve opening (V (max)), onset of atrial systole (p-wave at the electrocardiography = V (p)) and mitral valve closure (V (min)) according to the biplane area length method at baseline and in the 3rd month after the administration of beta blockers. NT-proBNP level was measured at the beginning and in the third month of beta blocker treatment. The first group was given carvedilol 6.25 mg/day, the second group was given 12.5 mg/day metoprolol succinate and it was increased to the tolerable maximal dose. LA diameter and LA V (max), V (p), V (min) decreased significantly both in carvedilol group and metoprolol group after beta blocker theraphy (P < 0.01, : P < 0.01, : P < 0.05, : P < 0.05: for metoprolol, P < 0.001, P < 0.01, P < 0.01, P < 0.01 for carvedilol). But it was increased in conduit volume (P < 0.05 for two groups). LA-passive emptying fraction, LA-active emptying fraction and reservoir fraction were no significant differences both in carvedilol group and metoprolol group after beta blocker theraphy. NT-proBNP levels were found to decrease significantly in both groups after beta blocker treatment (P < 0.001).: Our findings indicate that beta blocker treatment leads to a decrease in LA diameters and volumes, and metoprolol succinate and carvedilol had similar effects on this decrease.

Two-Dimensional Echocardiographic Methods for Assessment of Left Atrial Volume

Left atrial (LA) size is an important predictor of cardiovascular events. Various methods of LA volume assessment exist, but their differences have not been defined. This prospective study included 631 patients (331 men; mean age of 68 +/- 14 years) without a history of atrial arrhythmias, stroke, valvular heart disease, pacemaker implantation, or congenital heart disease. All underwent echocardiography with comprehensive diastolic function assessment and LA volume measurement by 3 commonly used methods: biplane area-length, biplane Simpson's method, and the prolate-ellipsoid method. Mean LA volumes were 39 +/- 14 ml/m2 by the area-length method, 38 +/- 13 ml/m2 by the Simpson's method, and 32 +/- 14 ml/m2 by the prolate-ellipsoid method. In 92% of patients, the prolate measurement was smaller than the 2 biplane methods. Pairwise correlations (r) were 0.98 for area-length versus Simpson's, 0.85 for prolate versus area-length, and 0.86 for prolate versus Simpson's (all p values <0.001). For distinguishing normal (n = 62) from pseudonormal diastolic function (n = 240) using receiver-operating curve analysis, areas under the curves were 0.76, 0.78, and 0.75 for the area-length, Simpson's, and prolate methods, respectively (all p values <0.001, no significant intermethod differences). In conclusion, our findings suggest that there are systematic differences among existing LA volume methods. Biplane area-length and Simpson's methods compare closely, whereas the prolate-ellipsoid method generally yields smaller volumes.

2388: Left atrial volume predicts cardiovascular complications in patients with hypertrophic cardiomyopathy

Objectives: To prospectively evaluate relationship between left atrial volume (LAV) and risk of complications in patients with hypertrophic cardiomyopathy (HCM). Methods: We studied 141 patients of HCM with sinus rhythm and normal left ventricular (LV) function at the time of enrollment. 102 patients were subsequently followed for 29.9 ± 10.4 mo. Using transthoracic echocardiography, LV end-diastolic dimension (LVDd), LV end-systolic dimension (LVDs) and ejection fraction (EF) were measured. LAV was off-line estimated by biplane area-length method. Maximum LAV indexed to body surface area (BSA) [LAV/BSA] was assessed. Complications mean cerebral infarction, sudden death and congestive heart failure. Results: Twenty-four patients showed complications (group A). LVDd, LVDs, EF and LA diameter (LAD) were not significantly different between group A and B (patients without complications) (LVDd; 4.36 ± 0.51 versus 4.33 ± 0.49 cm, p = 0.77, LVDs; 2.64 ± 0.50 versus 2.57 ± 0.55 cm, p = 0.62, EF; 67.5 ± 6.2 versus 66.5 ± 6.8%, p = 0.53, LAD; 3.91 ± 0.56 versus 3.80 ± 0.59 cm, p = 0.40: group A versus B). Maximum LAV, minimum LAV and LAV/BSA were significantly increased in group A (maximum LAV; 64.3 ± 25.0 versus 51.9 ± 16.0 ml, p = 0.005, minimum LAV; 33.9 ± 15.1 versus 26.2 ± 10.9 ml, p = 0.008, LAV/BSA; 40.1 ± 15.4 versus 31.5 ± 8.7 ml/mm2, p = 0.0009: group A versus B). Conclusions: LAV indices are sensitive markers to distinguish risk carriers among patients with HCM who show normal LV systolic function.

Predictive Value of Normal Left Atrial Volume in Stress Echocardiography

Our objective was to evaluate whether normal left atrial volume index (LAVI) is a predictor of a normal stress echocardiogram and thus a predictor of low ischemic risk. Left atrial enlargement is closely related to the chronicity and intensity of the burden of increased ventricular filling pressure. Typically ischemic heart disease (IHD) has a long period of subclinical dysfunction. Increased filling pressure, reflected by enlarged LAVI, is hypothesized to mirror the burden of subclinical and overt IHD. We hypothesized that a normal LAVI might also be useful in predicting low IHD risk. One hundred eighty randomly selected patients (mean age, 63 +/- 15 years; 53% men) underwent outpatient exercise or dobutamine stress echocardiography for known or suspected coronary artery disease. Left atrial volume index was measured retrospectively with the biplane area-length method. The stress echocardiogram was interpreted as abnormal if wall motion abnormalities (WMAs) were noted at rest and/or with stress. Left atrial volume index was categorized as < or =28 ml/m2 (normal), 28.1 to 32 ml/m2, 32.1 to 36 ml/m2, and >36 ml/m2. Abnormal stress echocardiography was identified in 57 patients (31.7%). The percentage of abnormal stress echocardiograms in each LAVI category was 5.7%, 21.9%, 38.7%, and 54.7%, respectively. The negative predictive value for LAVI < or =28 ml/m2 was 94.3%. Normal resting LAVI (< or =28 ml/m2) was strongly predictive of a normal stress echocardiogram. Left atrial volume index might be a simple means of identifying patients with low ischemic risk and should be further evaluated as a complement to the assessment of ischemic risk.

Left atrial mechanical functions in pre‐eclampsia

To assess the effect of short-term pressure overload on left atrial (LA) mechanical function in pre-eclampsia. Twenty women with pre-eclampsia and 17 age-matched healthy pregnant women were included. LA volumes were measured echocardiographically at the time of mitral valve opening (Vmax), onset of atrial systole (p-wave at the electrocardiography = Vp) and mitral valve closure (Vmin) according to the biplane area-length method. The mean age, gestational age, weight and body surface area were similar in pre-eclampsia and controls. The ventricular septal and posterior wall thickness were greater in pre-eclampsia (P < 0.001). There were no significant differences in LA diameter, Vmax, Vmin, Vp, LA-passive emptying volume, LA-passive emptying fraction, LA-active emptying volume, LA-active emptying fraction, conduit volume, LA-total emptying volume and LA-total emptying fraction between the groups. Left atrial mechanical function didn't change in pre-eclampsia. We conclude that short-lasting pressure overload is not capable of inducing changes in LA function.

Use of Real-time Three-dimensional Echocardiography to Measure Left Atrial Volume: Comparison with Other Echocardiographic Techniques

Left atrial (LA) volume (LAV) is a prognostically important biomarker for diastolic dysfunction, but its reproducibility on repeated testing is not well defined. LA assessment with 3-dimensional (3D) echocardiography (3DE) has been validated against magnetic resonance imaging, and we sought to assess whether this was superior to existing measurements for sequential echocardiographic follow-up. Patients (n = 100; 81 men; age 56 +/- 14 years) presenting for LA evaluation were studied with M-mode (MM) echocardiography, 2-dimensional (2D) echocardiography, and 3DE. Test-retest variation was performed by a complete restudy by a separate sonographer within 1 hour without alteration of hemodynamics or therapy. In all, 20 patients were studied for interobserver and intraobserver variation. LAVs were calculated by using M-mode diameter and planimetered atrial area in the apical 4-chamber view to calculate an assumed sphere, as were prolate ellipsoid, Simpson's biplane, and biplane area-length methods. All were compared with 3DE. The average LAV was 72 +/- 27 mL by 3DE. There was significant underestimation of LAV by M-mode (35 +/- 20 mL, r = 0.66, P < .01). The 3DE and various 2D echocardiographic techniques were well correlated: LA planimetry (85 +/- 38 mL, r = 0.77, P < .01), prolate ellipsoid (73 +/- 36 mL, r = 0.73, P = .04), area-length (64 +/- 30 mL, r = 0.74, P < .01), and Simpson's biplane (69 +/- 31 mL, r = 0.78, P = .06). Test-retest variation for 3DE was most favorable (r = 0.98, P < .01), with the prolate ellipsoid method showing most variation. Interobserver agreement between measurements was best for 3DE (r = 0.99, P < .01), with M-mode the worst (r = 0.89, P < .01). Intraobserver results were similar to interobserver, the best correlation for 3DE (r = 0.99, P < .01), with LA planimetry the worst (r = 0.91, P < .01). The 2D measurements correlate closely with 3DE. Follow-up assessment in daily practice appears feasible and reliable with both 2D and 3D approaches.

Left atrial systolic reserve in idiopathic vs. ischaemic‐dilated cardiomyopathy

There are studies indicating more pronounced left atrial (LA) systolic dysfunction at rest in idiopathic (IDDC) than in ischaemic-dilated cardiomyopathy (ISDC). It was hypothesized that the findings would be similar with regards LA systolic reserve. Twenty-six patients with IDDC, 28 with ISDC and 25 normal controls underwent low-dose dobutamine stress echocardiography (5-10 microg kg(-1) min(-1) IV). Left atrial volumes were echocardiographically determined at rest and during stress at the mitral valve opening (maximal, Vmax), electrocardiographic P wave (onset of atrial systole, Vp) and mitral valve closure (minimal, Vmin) from the apical 4- and 2-chamber views (biplane area-length method). Left atrial systolic function was assessed with the LA-active emptying volume (ACTEV) = Vp-Vmin and fraction (ACTEF) = ACTEV/Vp. Vmax at rest was similar in IDDC and ISDC and greater than in the controls (54.2 +/- 12 vs. 48.5 +/- 18 vs. 27.1 +/- 6.3 cm(3) m(-2), respectively, P < 0.001) and did not change with stress (53.9 +/- 13.8 vs. 46.9 +/- 16.2 vs. 25.8 +/- 5.9 cm(3) m(-2), P < 0.001). The ACTEV at rest was similar in IDDC and ISDC and greater than in the controls (8.6 +/- 3.5 vs. 9.7 +/- 2.9 vs. 6.1 +/- 2.2 cm(3) m(-2) P < 0.01), whereas during the dobutamine infusion it remained unaltered in IDDC (10.8 +/- 4.6 cm(3) m(-2), P = NS vs. rest) and increased in ISDC (11.8 +/- 3.3 cm(3) m(-2), P < 0.05) and the controls (13.1 +/- 3.2 cm(3) m(-2), P < 0.01). The ACTEF was lower in IDDC than ISDC and the controls at rest (20 +/- 10% vs. 33 +/- 8% vs. 36 +/- 10%, P < 0.01). Dobutamine infusion was associated with no significant increase in ACTEF in IDDC (25 +/- 12%, P = NS vs. rest), and with an increase in this variable in ISDC (39 +/- 10%, P < 0.05) and the controls (49 +/- 12%, P < 0.01). Dobutamine infusion is associated with an increase in LA ACTEV and fraction in ISDC and no significant change in these indices in IDDC. These findings indicate a reduced LA systolic reserve in IDDC.

Effect of cardiac resynchronization therapy on left atrial electromechanical function

Background: Cardiac resynchronization therapy (CRT) is effective in improving cardiac function and symptoms in patients (pts) with advanced heart failure (HF) and ventricular conduction abnormalities. These results are thought to be secondary to reduction in ventricular dyssynchrony and mitral regurgitation (MR). However, effects of CRT on left atrial (LA) function and interatrial conduction (IAC) are unknown. LA dysfunction and prolonged IAC are associated with decreased left ventricular (LV) filling and atrial fibrillation (AF). Accordingly, we studied the effects of CRT on LA function and IAC. Methods: Fifty-six pts (39m, 17f, 67 10 yr) with NYHA III-IV CHF, LV ejection fraction 35%, a QRS interval 130 msec on optimal medical therapy for HF underwent CRT (Medtronic InSync or Guidant Contak CD). P max (maximum P wave duration on any lead) and P disp (difference between P max and minimum P wave duration) were measured on a 12-lead ECG at baseline and at 6 months post CRT. Echocardiograms were recorded in a subset of 27 pts at baseline and at 6 months post CRT. Using the biplane area-length method, LA volumes at mitral opening, onset of P wave and mitral closure were determined. Based on Simpson’s formula, LA stroke volume (LASV), ejection fraction (LAEF) and kinetic energy (LAKE) were calculated. Peak A wave velocity (Avel) and A wave acceleration time (At) were also measured. Results: While LA volumes, At and Avel were similar at baseline and post CRT, there was a marked reduction in P max (143 23 msec vs. 132 27 msec, p 0.01)) and P disp (35 13 msec vs. 22 13 msec, p 0.01) 6 months post CRT. There was also a significant improvement in LASV (7.5 4 ml vs. 20 15 ml, p 0.01), LAEF (19 6% vs. 29 20%, p 0.01) and LAKE (28 20 Kdyne/cm/s vs. 70 40 Kdyne/cm/s, p 0.01) at 6 months. Conclusions: CRT results in marked reduction in IAC delay and significant improvement in LA systolic function. Although LA volumes did not change, LASV, LAEF, and LAKE improved at 6 months. Enhanced LA electromechanical function may result in improved LV filling and contribute to the hemodynamic and symptomatic improvement observed with CRT and has implications for reduction in the propensity for AF.

Acute short term ultrafiltration produces sustained hemodynamic benefits in acutely decompensated heart failure patients

the relationship between left atrial volume index (LAVI) to PkVO2. Methods: In 82 patients with advanced systolic dysfunction (EF 19 8%), we measured LAVI by the biplane area-length method from apical 4 and 2-chamber views (indexed for body surface area). PkVO2 was measured by metabolic cart during maximal exercise and further adjusted to lean body mass (PkVO2lean). We have previously demonstrated that PkVO2lean cutoff of 19 ml/kg/min is better predictor of event free survival than unadjusted PkVO2. Results: In patients whose PkVO2lean was 19 ml/kg/min, the mean LAVI was 44.8 ml/m whereas LAVI was 54.7 ml/m2 in patients with PkVO2lean 19 ml/kg/min (p 0.04). An LAVI 65 ml/m 2 predicts PkVO2lean 19 ml/kg/min with a positive predictive value of 77% and a negative predictive value of 68%. Conclusions: Left atrial volume, a simple echocardiographic parameter, provides discriminatory prediction for functional circulatory impairment further in patients with severe systolic dysfunction. Thus, this investigation suggests that the finding of an increased left atrial volume index 65ml/m reflects worse diastolic dysfunction and should prompt assessment of metabolic reserve by cardiopulmonary stress testing.

Left atrial systolic function in primary and familial amyloidosis: assessment from left atrial volume change.

The severity of left ventricular involvement may differ between primary (PA) and familial amyloidosis (FA). This study examined whether differences in left atrial (LA) systolic function are also present. Twenty-eight patients (18 men, 10 women, aged 59 +/- 12 years) with PA, 17 (11 men, 6 women, aged 40 +/- 11 years) with FA, and 25 normal controls (18 men, 7 women, aged 56 +/- 14 years) underwent transthoracic M-mode, two-dimensional, and Doppler echocardiography. Left atrial volumes were determined at mitral valve (MV) opening (maximal, Vmax), electrocardiographic P wave (onset of atrial systole, Vp), and MV closure (minimal, Vmin) from the apical two-and four-chamber views using the biplane area-length method. Left atrial systolic function was assessed with the LA active emptying volume (ACTEV) = Vp-Vmin and fraction (ACTEF) = ACTEV/Vp. The E/A ratio was increased (1.34 +/- 0.93 vs. 0.89 +/- 0.3), whereas deceleration time was decreased (168.1 +/- 33.7 vs. 196.2 +/- 34.2 ms) in PA compared with FA (p<0.05). Vmax and Vp were similar in PA and FA and greater than in the controls (46.6 +/- 14 vs. 40 +/- 11.4 vs. 27.1 +/- 6.3 cm3/m2, p<0.01, and 33.4 +/- 11.6 vs. 29.7 +/- 10.8 vs. 16.8 +/- 3.8 cm3/m2, p<0.01, respectively). The ACTEV was lower in PA and in the controls than in FA (6.7 +/- 2 vs. 6.2 +/- 2.2 vs. 8.5 +/- 3.3, respectively, p<0.05). The ACTEF was lower in PA than in FA and both were lower than those in the controls (20 +/- 5% vs. 28 +/- 7% vs. 36 +/- 11%, respectively, p<0.01). Despite a similar increase in LA volume, LA systolic dysfunction is more pronounced in PA than in FA. This is most likely due to the restrictive left ventricular physiology possibly associated with depressed LA contractility in the former.