BACKGROUND: Isovolumic acceleration (IVA) as assessed by Tissue Doppler Imaging (TDI) has been proposed as a measure of left ventricular (LV) contractility. IVA is believed to be less dependent on preload than previously proposed estimates. IVA has been measured at different locations, and studies have shown conflicting results. OBJECTIVES: We investigated the impact of increased preload on modern echocardiographic estimates of contractility, including IVA performed at different locations, in healthy volunteers. METHODS: Seventeen young healthy individuals (male 13, age 31(+/- 9) years) with no prior history of cardiovascular or metabolic diseases had a Doppler and Tissue Doppler echocardiographic study performed at baseline and after a rapid infusion of 30 ml/kg of bodyweight of isotonic saline. Results are given as mean +/- standard deviation (SD), differences tested by paired t-test. RESULTS: Echocardiographic parameters used to determine changes in preload, altered significantly. E/e' increased both at the lateral (5 +/- 1 vs 7 +/- 1 P < 0.01) and at the septal side of the annulus (7 +/- 2 vs 9 +/- 2, P < 0.01). Afterload remained unchanged. IVA was unchanged regardless of the measurement location: in the basal free wall (1.21 +/- 0.58 vs 0.98 +/- 0.41, not significant (NS)) or in the mitral annulus (1.18 +/- 0.56 vs 1.15 +/- 0.33, NS). Peak systolic strain, measured at the basal segment of LV septum, increased significantly (15.4 +/- 5.0 vs 20.7 +/- 5, P < 0.05), while all other measurements for strain or strain rate (SR) remained unchanged. CONCLUSION: IVA is unchanged following significant increases in preload in healthy subjects, and thus is a potentially useful measure of global LV contractility.
BACKGROUND: Isovolumic acceleration (IVA) as assessed by Tissue Doppler Imaging (TDI) has been proposed as a measure of left ventricular (LV) contractility. IVA is believed to be less dependent on preload than previously proposed estimates. IVA has been measured at different locations, and studies have shown conflicting results. OBJECTIVES: We investigated the impact of increased preload on modern echocardiographic estimates of contractility, including IVA performed at different locations, in healthy volunteers. METHODS: Seventeen young healthy individuals (male 13, age 31(+/- 9) years) with no prior history of cardiovascular or metabolic diseases had a Doppler and Tissue Doppler echocardiographic study performed at baseline and after a rapid infusion of 30 ml/kg of bodyweight of isotonic saline. Results are given as mean +/- standard deviation (SD), differences tested by paired t-test. RESULTS: Echocardiographic parameters used to determine changes in preload, altered significantly. E/e' increased both at the lateral (5 +/- 1 vs 7 +/- 1 P < 0.01) and at the septal side of the annulus (7 +/- 2 vs 9 +/- 2, P < 0.01). Afterload remained unchanged. IVA was unchanged regardless of the measurement location: in the basal free wall (1.21 +/- 0.58 vs 0.98 +/- 0.41, not significant (NS)) or in the mitral annulus (1.18 +/- 0.56 vs 1.15 +/- 0.33, NS). Peak systolic strain, measured at the basal segment of LV septum, increased significantly (15.4 +/- 5.0 vs 20.7 +/- 5, P < 0.05), while all other measurements for strain or strain rate (SR) remained unchanged. CONCLUSION:IVA is unchanged following significant increases in preload in healthy subjects, and thus is a potentially useful measure of global LV contractility.
Authors: Thad E Wilson; Zhaohui Gao; Kari L Hess; Kevin D Monahan Journal: Am J Physiol Regul Integr Comp Physiol Date: 2010-04-07 Impact factor: 3.619
Authors: R Matthew Brothers; Paul S Bhella; Shigeki Shibata; Jonathan E Wingo; Benjamin D Levine; Craig G Crandall Journal: Am J Physiol Heart Circ Physiol Date: 2009-02-13 Impact factor: 4.733
Authors: N A Bayram; R Ersoy; C Aydin; K Gul; T Keles; O Topaloglu; T Durmaz; E Bozkurt; B Cakir Journal: J Endocrinol Invest Date: 2009-03 Impact factor: 4.256
Authors: Saurabh Kumar Gupta; Km Krishnamoorthy; Jaganmohan A Tharakan; S Sivasankaran; G Sanjay; S Bijulal; T Anees Journal: Ann Pediatr Cardiol Date: 2011-07
Authors: Sebastian Schattke; Fabian Knebel; Andrea Grohmann; Henryk Dreger; Friederike Kmezik; Gabriela Riemekasten; Gert Baumann; Adrian C Borges Journal: Cardiovasc Ultrasound Date: 2010-01-22 Impact factor: 2.062