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Aims Left atrial volume (LAV) has been proposed as a predictor of atrial fibrillation (AF) and LA function has been investigated by velocity vector imaging (VVI) echocardiography. The aim of this study was to determine whether LA function was associated with the existence of AF. Methods and results We examined emptying function (EF) as a global function and strain rate (SR) as a regional function of LA function during three phases of the cardiac cycle (reservoir, conduit, and booster pump phase). The parameters were measured (apical four-chamber view) by VVI in 302 subjects [126 sinus rhythm, 91 paroxysmal AF (PAF), and 85 chronic AF]. Global and regional LA function were significantly lower in PAF patients during sinus rhythm (LA total EF: 35 ± 8%; SR at atrial contraction: −0.8 ± 0.3s−1) and much lower in chronic AF patients (LA total EF 22 ± 8%) than in subjects with sinus rhythm (LA total EF: 47 ± 7%; SR at atrial contraction: −1.4 ± 0.4s−1). In multivariate logistic regression analysis, LA active EF and SR at atrial contraction were independent features of PAF. Conclusion LA function, particularly LA active relaxation and contraction, was lower in PAF patients than in subjects with sinus rhythm, regardless of LA size and age. LA functional impairment was observed regardless of hypertension before LA enlargement in patients with PAF. Reduced LA function, as assessed by VVI, is an important feature of AF as well as LA structure. [ABSTRACT FROM PUBLISHER]

Introduction: Left ventricular (LV) pressure-volume (P-V) loop area reflects stroke work (SW), but clinical use of this index is limited by the need of invasive pressure measurement. A noninvasive method to obtain LV pressure-strain loop was recently introduced to assess myocardial work (MW). We sought to evaluate the impact of preload change by leg lifts on LV SW noninvasively obtained by the novel method and to examine the utility to assess LV contractility by SW and end-diastolic (ED) volume relation (SW-VED). Methods: Thirty six controls (age 71±10) and 24 patients with heart failure with reduced ejection fraction (EF) <50% (HF) (age 73±6) were enrolled. LV pressure in a cardiac cycle was estimated using systolic blood pressure (SBP), minimum diastolic pressure (mDP) and ED pressure (EDP) by utilizing the profile of an empiric, normalized reference curve. The mDP and EDP were estimated as 5mmHg and as 12.3 - 10.1 x Log (left atrial active emptying function / minimum volume) as we reported. SW was obtained by P-V loop by the combination of these pressures and LV volume using 3-dimensional speckle tracking echocardiography. Results: LVEF and longitudinal strain in HF before leg up were lower compared to normal (LVEF; normal: 65±6 vs HF: 40±9*% and strain; -12±3 vs -8±3%*, *p<0.05 vs normal). LVEF was increased after leg up by 7±6% in normal and by 9±8% in HF associated with increased LVED volume (normal: 84±24 to 90±24 and HF: 124±37* to 136±43*ml). LV MW and SW in HF before leg up were lower compared to normal (MW: 1790±412 vs 1045±423*mmHg% and SW: 3946±1682 vs 3628±983mmHgml). LV SW increased after leg up by 26±19% in normal and by 33±23 % in HF. LV SW-VED in normal was greater than HF (241±151 vs 97±50*). Conclusions: LV SW noninvasively obtained by P-V loop area was increased after leg up in both normal and HF but SW-VED in HF was smaller than normal, indicating reduced contractility in HF. This noninvasive method may be a new echocardiographic approach for quantification of LV SW and contractility. [ABSTRACT FROM AUTHOR]

Introduction: Left ventricular (LV) relaxation in a cardiac cycle is characterized by rapid torsional recoil of LV wall. LV torsion is caused by the contraction of inner and outer oblique muscle and followed by untorsion. Predominant epicardial stretch along myofibers during isovolumic relaxation (IVR) appears to drive global torsional recoil to aid early diastolic filling. However, contribution of transmural arrangement of myofibers to relaxation was not elucidated by echocardiography. The aim of this study was to evaluate whether torsion slope during early diastole (untorsion slope) on time-torsion curve by 3-dimensional speckle tracking echocardiography (3D-STE) could serve as a feasible index of LV relaxation. Methods: Forty five patients with cardiac disease (age 70±10) were prospectively enrolled in this study. The time constant of LV pressure decline (Tau) was obtained by cardiac catheterization as a gold standard for LV relaxation and compared with LV diastolic echo parameters including the untorsion slope. Echocardiography was performed just before the left sided heart catheterization. We examined the LV strain rate of early diastole (SR-E) and isovolemic relaxation time (SR-IVR), and time-torsion curve by 3D-STE in addition to conventional echo parameters such as LV mass index (LVMI), Left atrial volume (LAV), e' and isovolumic relaxation time (IVRT). From the time-LV torsion curve (Figure), we calculated the untorsion slopes from peak to the points of 25%, 33%, and 50% of total untorsion phase (from peak torsion time to minimum torsion time). Results: Table Conclusions: This study demonstrated that the untorsion slope by our noninvasive method using 3D-STE had a good correlation with Tau obtained by cardiac catheterization. The analysis of the untorsion slope on the time-LV torsion curve may be a useful and novel method to estimate LV relaxation and have a clinical value to detect the early stage of diastolic dysfunction. [ABSTRACT FROM AUTHOR]

Introduction: We reported that pulmonary capillary wedge pressure (ePCWP) and time constant of left ventricular (LV) pressure decline (eTau) are noninvasively estimated by speckle tracking echocardiography (STE). LV camber stiffness (e-c stiffness) may be estimated with the use of 2 diastolic pressure-volume coordinates: the end-diastolic pressure (EDP) and volume and the pressure and volume at the time of minimum diastolic pressure (mP). Myocardial stiffness (e-m stiffness) may be assessed using stress and strain by STE. We sought to validate e-c stiffness and e-m stiffness by STE against those by catheterization and to evaluate the clinical utility in patients with normal LVEF. Methods: Validation was performed in 126 patients and LV chamber stiffness was obtained as LV pressure change (EDP minus mP) by catheterization divided by LV volume change that equals to stroke volume by echocardiography. STE was performed in 58 controls, 110 hypertension (HTN), 155 HTN with hemodialysis (HD), 48 HTN heart failure with preserved EF (HFpEF) and 34 aortic stenosis (AS). The ePCWP was noninvasively calculated as 10.8 - 12.4 x Log (left atrial active emptying function / minimum volume) (KT index). LVEDP (e-EDP) was estimated as 12.3 - 10.1 x KT index. The eTau is obtained as isovolumic relaxation time / (ln 0.9 x systolic blood pressure - ln ePCWP). The e-c stiffness was noninvasively obtained using e-EDP and 5 mmHg as mP because mP by catheterization was 5.0±2.9mmHg. LVED stress (e-stress) was estimated as e-EDP x LV dimension / thickness. Results: The eTau and e-EDP by STE had a good correlation with Tau and EDP by catheterization (r=0.75 and 0.63, p<0.001). The e-c stiffness and e-stress had a good correlation with stiffness and stress by catheterization (r=0.69 and 0.77, p<0.001). LV stiffness was most increased in HFpEF. Conclusions: LV relaxation and LV stiffness may be noninvasively assessed by STE with reasonable accuracy and may have a utility and value in the routine clinical practice. [ABSTRACT FROM AUTHOR]

Introduction: Left ventricular (LV) pressure-strain loop and pressure-volume loop area reflect myocardial work (MW) and stroke work (SW). However, clinical use of these indexes is limited by the need of invasive pressure measurement. A noninvasive method to obtain LV pressure-strain loop area was recently introduced. We sought to evaluate global MW and SW by LV pressure-strain and pressure-volume loop area by 3-dimensional speckle tracking echocardiography (3D-STE) in heart failure (HF) and compare those indexes with controls to elucidate the utility of the indexes. Methods: STE was performed and systolic blood pressure (SBP) was measured in 24 patients with HF and ejection fraction (EF) < 50% (age 73±6) and 36 controls (71±10). LV pressure was estimated using SBP, minimum diastolic pressure (mDP) and end-diastolic pressure (EDP) by utilizing the profile of an empiric, normalized reference curve which was adjusted according to the duration of LV isovolumic and ejection phases. The mDP and EDP were estimated as 5mmHg and as 12.3 - 10.1 x Log (left atrial active emptying function / minimum volume) as we reported. LV SW was obtained by LV pressure-volume loop area using the combination of pressure (SBP, mDP and EDP) and volume by 3D-STE. Results: LV pressure-volume loop was noninvasively obtained. LVEF and longitudinal strain in HF reduced compared to normal (LVEF; normal: 65±6 vs HF: 40±9*%, strain; -12±3 vs -8±3*%, *p<0.05 vs normal). LV end diastolic and systolic volume in HF increased compared to normal (84±24 vs 124±37* and 35±13 vs 78±34*ml). LV MW in HF reduced compared to normal (1790±412 vs 1045±423*mmHg%) and SW in HF tended to decrease (3946±1682 vs 3628±983mmHgml). MW had a good correlation with strain (r=0.60, p<0.01) and SW had a correlation with stroke volume (r=0.69, p<0.01). Conclusions: LV global MW and SW were noninvasively obtained by LV pressure-strain and volume area by 3D-STE. This novel noninvasive method may have a clinical interest and value to assess LV function. [ABSTRACT FROM AUTHOR]

Introduction: Left atrium (LA) is very complex due to close coupling with left ventricle (LV). LA structural remodeling and functional impairment might play an important part in the pathogenesis and development of ventricular disorders such as heart failure (HF) with or without preserved LV ejection fraction (EF). Speckle tracking echocardiography (STE) makes it possible to measure phasic LA volume (LAV) and function with relatively high accuracy. We investigated LA features in relation to LV disorders due to hypertension (HTN) by STE. Methods: We performed STE in 58 controls, 60 HTN without LVH, 76 HTN with LVH, 40 HF with preserved EF (HFpEF) and 62 HF with reduced EF (HFrEF). We measured phasic LAV {maximum, pre-atrial contraction (AC) and minimum}, phasic LA emptying function (LAEF) (total, passive and active LAEF} and LA peak strain and phasic strain rate (SR) {SR during LV systole (SR-S), early filling (SR-E) and AC (SR-AC)}. Pulmonary capillary wedge pressure (PCWP) was calculated as we previously reported. LA stiffness was estimated as PCWP / LA strain. LV stiffness was estimated as LV end-diastolic stress / LV strain, where LV stress was calculated as PCWP x LV endo-diastolic dimension / thickness. Results: PCWP and LV and LA stiffness increased from HTN without LVH to HFrEF. There was a correlation between active LAEF and LASR-AC (r=-0.62, p<0.01). Active LAEF and LASR-AC in HTN with LVH were preserved and similar to those of controls despite increased LAV and decreased total LAEF, but decreased in HFpEF and HFrEF associated with increased LAV, PCWP and LV stiffness. Multivariate analysis revealed that LASR-AC and LA stiffness are independent predictors of HF. Conclusions: LA booster pump function assessed by LASR-AC may play a compensatory mechanism to maintain LVEF with increased LA preload assessed by PCWP against increased afterload by LV stiffness, but was broken down in HHF, suggesting that impairment of LA booster function and increased LA stiffness may lead to HHF in HTN. [ABSTRACT FROM AUTHOR]

Introduction: Left ventricular (LV) diastolic dysfunction in normal ejection fraction (EF) is clinically diagnosed by mitral annular tissue velocity (e'), the ratio of early mitral inflow velocity to tissue velocity (E/e'), tricuspid regurgitant velocity and left atrial volume (LAV). We reported that time constant of LV pressure decline (Tau) and pulmonary capillary wedge pressure (PCWP) are noninvasively and accurately estimated by speckle tracking echocardiography (STE). We sought to examine the most reliable predictor of LV diastolic dysfunction among echo parameters. Methods: The e', E/e', Tau, PCWP, LV end-diastolic pressure (EDP), LV myocardial stiffness, LAV, LA emptying function (LAEF) and LA strain were examined by STE in 58 controls (age 67±11), 136 hypertensive patients (HTN) (69±11) and 40 hypertensive heart failure (HF) with preserved LVEF>50% (HFpEF) (77±14) that has a predominant diastolic dysfunction. PCWP was calculated as 10.8 – 12.4 Log (active LAEF / minimum LAV) (KT index). EDP was estimated as 12.3 – 10.1 x KT index as we reported. Tau was calculated as isovolumic relaxation time / (ln 0.9 x systolic blood pressure – ln PCWP). LV stiffness was estimated as ED stress / LV strain by 3D-STE, where ED stress was calculated as 0.334 x PCWP x LV dimension / {LV thickness (1 + LV thickness / LV dimension)}. Tau and EDP by STE were validated by catheterization (n=126). Results: Tau and LVEDP by STE had a good correlation with those by catheterization (r=0.75 and 0.63, p<0.001). The E/e', LVEDP and stiffness increased, LA strain decreased and Tau was prolonged in HFpEF. Multivariate analysis revealed that LVEDP and LA strain were independent predictors of HFpEF among echo parameters. Using LVEDP cutoff of 12.5, the sensitivity and specificity for HFpEF is 83 and 81% with AUC of 0.89. Conclusion: We demonstrated that the diagnosis of diastolic dysfunction may be more accurately and noninvasively performed using LVEDP and LA strain by STE than conventional echo parameters. [ABSTRACT FROM AUTHOR]