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Strain and Strain Rate: Effect of Load and Relation with Invasive Indices of Cardiac Function
S54
Heart, Lung and Circulation 2009;18S:S1–S286
Abstracts
ABSTRACTS
the 144 enrolled were diagnosed with endocarditis defined as either definite or possible endocarditis by Duke’s criteria. Of the 41 patients with the diagnosis of endocarditis, 37 (90.2%) had echocardiographically confirmed vegetations. Of the 41 cases of endocarditis, 22 (53.7%) were not suspected clinically by Duke minus. The clinical diagnosis of endocarditis had a sensitivity of 46% and specificity of 97%. Conclusion: There is a high incidence of endocarditis in SAB and a large percentage of cases are not evident on clinical grounds. TOE evaluation is indicated for all medically suitable patients with SAB to improve detection of endocarditis. doi:10.1016/j.hlc.2009.05.117 116 STRAIN AND STRAIN RATE EVALUATION OF ATRIAL PHASIC FUNCTION IN NORMAL AGING A.C. Boyd 1,2 , D.L. Ross 2 , L. Thomas 1,3 1 University
of NSW, Sydney, Australia Hospital, Sydney, Australia 3 Liverpool Hospital, Sydney, Australia 2 Westmead
Background: Strain (SI) and strain rate (SR) measure local deformation of the myocardium and more recently has been used to evaluate atrial function. The aim of this study was to determine the effects of normal aging on phasic atrial function evaluated by strain parameters. Methods: Transthoracic echocardiograms were performed on 188 normal subjects and analyzed by decades. SI and SR were measured from superior segments in both the apical 4 and 2 chamber views of the LA, and global values calculated as the mean of the 4 segments. Measurements included peak systolic SI and S sr (atrial relaxation), early diastolic SI and E sr (passive contraction) and late diastolic A sr (active contraction). Results: Systolic SI, S sr, diastolic SI, and E sr decreased significantly with increasing decade of life. Although A sr did increase, it only reached significance during Decade 7. Decade 3 (n = 40) Age (years) Systolic SI (%) S sr (s−1 ) Diastolic SI (%) E sr (s−1 ) A sr (s−1 )
‡
26 77 3.3 43 4.0 2.6
± ± ± ± ± ±
2 15 0.6 7 1.1 0.7
4 (n = 42) 35 72 3.3 41 3.4 2.7
± ± ± ± ± ±
3 15 0.7 9 1.1 0.7
5 (n = 29) 45 67 2.7 42 3.0 3.0
± ± ± ± ± ±
6 (n = 38)
7 (n = 25)
3 54 ± 3 65 ± 3 14 59 ± 15*† 55 ± 14*†‡ 0.6*† 2.5 ± 0.5*† 2.4 ± 0.6*† 7 39 ± 8 38 ± 6 1.1* 2.6 ± 0.7*† 2.1 ± 0.6*†‡ 0.7 2.9 ± 0.7 3.3 ± 0.8*†
8 (n = 14) 74 49 2.1 32 1.5 3.1
± ± ± ± ± ±
3 16*†‡ 0.6*†‡ 8*†‡ 0.4*†‡** 0.7
* p < 0.05 compared to Decade 3; † p < 0.05 compared to Decade 4; p < 0.05 compared to Decade 5; ** p < 0.05 compared to Decade 6.
Conclusion: Both LA relaxation and passive contraction decrease, reflecting progressive myocardial fibrosis that occurs with normal aging. Active LA contraction is augmented in later life to enhance LV filling. SI and SR can be used to measure intrinsic phasic atrial function. doi:10.1016/j.hlc.2009.05.118
117 STRAIN AND STRAIN RATE: EFFECT OF LOAD AND RELATION WITH INVASIVE INDICES OF CARDIAC FUNCTION Andrew T. Burns 1 , Andre La Gerche 1 , David L. Prior 1,2 , Andrew I. MacIsaac 1,2 1 Cardiac Investigation Unit, St Vincent’s Hospital Melbourne, Victoria, Australia 2 University of Melbourne, Department of Medicine, St Vincent’s Hospital Melbourne, Victoria, Australia
Background: Left ventricular strain and strain rate have been proposed as novel indices of cardiac function. There is limited data about the effect of acute changes in load on strain parameters and their relation to gold-standard invasive measures of cardiac function. Methods: Simultaneous Millar micromanometer LV pressure and echocardiographic assessment was performed on eighteen patients (10 male, mean age 66 years) with normal systolic function. Loading was altered by the administration of glyceryl trinitrate (GTN) and saline fluid loading. Echocardiographic speckle tracking imaging was used to quantify peak strain (S) and peak systolic strain rate (SR S) and early diastolic strain rate (SR E) in the radial (rad), circumferential (circ) and longitudinal (long) planes. Results: GTN administration decreased preload (LVEDP: 15.7 vs 8.4 mmHg, p < 0.001), and afterload (end systolic wall stress, ESWS: 74 vs 43 × 103 dyn/cm2 , p < 0.001). Administration of fluid increased preload (LVEDP 11.3 vs 18.1 mmHg, p < 0.001) and afterload, but to a lesser extent (ESWS: 53 vs 62 × 103 dyn/cm2 , p < 0.003). Administration of GTN resulted in reduced rad SR S (2.2v s 1.8 s−1 , p < 0.05) but increased circ SR S (−1.2 vs −1.7 s−1 , p < 0.01) and long SR S (−0.9 vs −1.0 s−1 , p < 0.001). The administration of fluid resulted in decreased circ SR S (−1.5 vs −1.3 s−1 , p < 0.01) and long SR S (−1.0 vs −0.9 s−1 , p < 0.01). As preload and afterload increased (increased EDP and ESWS respectively) circ SR S (r = 0.63, p < 0.001; r = 0.56, p < 0.001) and long SR S decreased (r = 0.42, p < 0.003; r = 0.49, p < 0.001). As dp/dt max increased, circ and long SR S increased (r = −0.49, p < 0.001; r = 0.35, p < 0.014). Conclusions: Systolic strain rates are related to dp/dt max but their sensitivity to changes in loading conditions needs to be considered in their application as indices of systolic function. doi:10.1016/j.hlc.2009.05.119
Heart, Lung and Circulation 2009;18S:S1–S286
Abstracts
ABSTRACTS
the 144 enrolled were diagnosed with endocarditis defined as either definite or possible endocarditis by Duke’s criteria. Of the 41 patients with the diagnosis of endocarditis, 37 (90.2%) had echocardiographically confirmed vegetations. Of the 41 cases of endocarditis, 22 (53.7%) were not suspected clinically by Duke minus. The clinical diagnosis of endocarditis had a sensitivity of 46% and specificity of 97%. Conclusion: There is a high incidence of endocarditis in SAB and a large percentage of cases are not evident on clinical grounds. TOE evaluation is indicated for all medically suitable patients with SAB to improve detection of endocarditis. doi:10.1016/j.hlc.2009.05.117 116 STRAIN AND STRAIN RATE EVALUATION OF ATRIAL PHASIC FUNCTION IN NORMAL AGING A.C. Boyd 1,2 , D.L. Ross 2 , L. Thomas 1,3 1 University
of NSW, Sydney, Australia Hospital, Sydney, Australia 3 Liverpool Hospital, Sydney, Australia 2 Westmead
Background: Strain (SI) and strain rate (SR) measure local deformation of the myocardium and more recently has been used to evaluate atrial function. The aim of this study was to determine the effects of normal aging on phasic atrial function evaluated by strain parameters. Methods: Transthoracic echocardiograms were performed on 188 normal subjects and analyzed by decades. SI and SR were measured from superior segments in both the apical 4 and 2 chamber views of the LA, and global values calculated as the mean of the 4 segments. Measurements included peak systolic SI and S sr (atrial relaxation), early diastolic SI and E sr (passive contraction) and late diastolic A sr (active contraction). Results: Systolic SI, S sr, diastolic SI, and E sr decreased significantly with increasing decade of life. Although A sr did increase, it only reached significance during Decade 7. Decade 3 (n = 40) Age (years) Systolic SI (%) S sr (s−1 ) Diastolic SI (%) E sr (s−1 ) A sr (s−1 )
‡
26 77 3.3 43 4.0 2.6
± ± ± ± ± ±
2 15 0.6 7 1.1 0.7
4 (n = 42) 35 72 3.3 41 3.4 2.7
± ± ± ± ± ±
3 15 0.7 9 1.1 0.7
5 (n = 29) 45 67 2.7 42 3.0 3.0
± ± ± ± ± ±
6 (n = 38)
7 (n = 25)
3 54 ± 3 65 ± 3 14 59 ± 15*† 55 ± 14*†‡ 0.6*† 2.5 ± 0.5*† 2.4 ± 0.6*† 7 39 ± 8 38 ± 6 1.1* 2.6 ± 0.7*† 2.1 ± 0.6*†‡ 0.7 2.9 ± 0.7 3.3 ± 0.8*†
8 (n = 14) 74 49 2.1 32 1.5 3.1
± ± ± ± ± ±
3 16*†‡ 0.6*†‡ 8*†‡ 0.4*†‡** 0.7
* p < 0.05 compared to Decade 3; † p < 0.05 compared to Decade 4; p < 0.05 compared to Decade 5; ** p < 0.05 compared to Decade 6.
Conclusion: Both LA relaxation and passive contraction decrease, reflecting progressive myocardial fibrosis that occurs with normal aging. Active LA contraction is augmented in later life to enhance LV filling. SI and SR can be used to measure intrinsic phasic atrial function. doi:10.1016/j.hlc.2009.05.118
117 STRAIN AND STRAIN RATE: EFFECT OF LOAD AND RELATION WITH INVASIVE INDICES OF CARDIAC FUNCTION Andrew T. Burns 1 , Andre La Gerche 1 , David L. Prior 1,2 , Andrew I. MacIsaac 1,2 1 Cardiac Investigation Unit, St Vincent’s Hospital Melbourne, Victoria, Australia 2 University of Melbourne, Department of Medicine, St Vincent’s Hospital Melbourne, Victoria, Australia
Background: Left ventricular strain and strain rate have been proposed as novel indices of cardiac function. There is limited data about the effect of acute changes in load on strain parameters and their relation to gold-standard invasive measures of cardiac function. Methods: Simultaneous Millar micromanometer LV pressure and echocardiographic assessment was performed on eighteen patients (10 male, mean age 66 years) with normal systolic function. Loading was altered by the administration of glyceryl trinitrate (GTN) and saline fluid loading. Echocardiographic speckle tracking imaging was used to quantify peak strain (S) and peak systolic strain rate (SR S) and early diastolic strain rate (SR E) in the radial (rad), circumferential (circ) and longitudinal (long) planes. Results: GTN administration decreased preload (LVEDP: 15.7 vs 8.4 mmHg, p < 0.001), and afterload (end systolic wall stress, ESWS: 74 vs 43 × 103 dyn/cm2 , p < 0.001). Administration of fluid increased preload (LVEDP 11.3 vs 18.1 mmHg, p < 0.001) and afterload, but to a lesser extent (ESWS: 53 vs 62 × 103 dyn/cm2 , p < 0.003). Administration of GTN resulted in reduced rad SR S (2.2v s 1.8 s−1 , p < 0.05) but increased circ SR S (−1.2 vs −1.7 s−1 , p < 0.01) and long SR S (−0.9 vs −1.0 s−1 , p < 0.001). The administration of fluid resulted in decreased circ SR S (−1.5 vs −1.3 s−1 , p < 0.01) and long SR S (−1.0 vs −0.9 s−1 , p < 0.01). As preload and afterload increased (increased EDP and ESWS respectively) circ SR S (r = 0.63, p < 0.001; r = 0.56, p < 0.001) and long SR S decreased (r = 0.42, p < 0.003; r = 0.49, p < 0.001). As dp/dt max increased, circ and long SR S increased (r = −0.49, p < 0.001; r = 0.35, p < 0.014). Conclusions: Systolic strain rates are related to dp/dt max but their sensitivity to changes in loading conditions needs to be considered in their application as indices of systolic function. doi:10.1016/j.hlc.2009.05.119