AIMS: The aim of the present study was to evaluate left ventricular (LV) function and contractile reserve (CR) with Doppler myocardial imaging (DMI) in a small animal model for type 1 diabetes. METHODS AND RESULTS: Cardiac function was assessed in anaesthetized Wistar rats 6 and 8 weeks after injection of 60 mg/kg of streptozotocin. At 6 weeks of diabetes, colour DMI echocardiography was performed at rest and during incremental dosages of dobutamine (5, 10, 20 microg/kg/min). Left ventricular fractional shortening was decreased after 8 weeks of follow-up [36 +/- 5 (D) vs. 41 +/- 4% (C); P = 0.049]. After 6 weeks of diabetes, DMI measurements were reduced in the diabetic rats in the inferolateral wall at rest [systolic velocity: 2.5 +/- 0.4 (D) vs. 4.4 +/- 0.3 (C) cm/s; P < 0.001; systolic strain rate: 12.2 +/- 3.4 (D) vs. 17.4 +/- 3.2 (C) 1/s; P = 0.012] and during inotropic stimulation [delta velocity (cm/s): 0.2 +/- 0.1 (D) vs. 0.5 +/- 0.3 (C)/5 microg dobutamine; P = 0.002; delta strain rate (1/s): 1.4 +/- 0.9 (D) vs. 3.3 +/- 2.2 (C)/5 microg dobutamine; P = 0.049]. Furthermore, the intraventricular delay in time-to-peak systolic strain was larger in diabetes [20 +/- 18 (D) vs. 10 +/- 7 (C) ms; P= 0.01]. Systolic mitral annular velocity was also lower in the diabetic rats at rest [2.7 +/- 0.4 (D) vs. 3.5 +/- 0.4 (C) cm/s; P < 0.001] and in response to dobutamine [delta velocity (cm/s): 0.1 +/- 0.1 (D) vs. 0.3 +/- 0.2 (C)/5 microg dobutamine; P = 0.013]. CONCLUSION: In experimental diabetes, a reduction in radial and longitudinal LV function and CR can be detected with DMI before the onset of a reduced global LV function.
AIMS: The aim of the present study was to evaluate left ventricular (LV) function and contractile reserve (CR) with Doppler myocardial imaging (DMI) in a small animal model for type 1 diabetes. METHODS AND RESULTS: Cardiac function was assessed in anaesthetized Wistar rats 6 and 8 weeks after injection of 60 mg/kg of streptozotocin. At 6 weeks of diabetes, colour DMI echocardiography was performed at rest and during incremental dosages of dobutamine (5, 10, 20 microg/kg/min). Left ventricular fractional shortening was decreased after 8 weeks of follow-up [36 +/- 5 (D) vs. 41 +/- 4% (C); P = 0.049]. After 6 weeks of diabetes, DMI measurements were reduced in the diabeticrats in the inferolateral wall at rest [systolic velocity: 2.5 +/- 0.4 (D) vs. 4.4 +/- 0.3 (C) cm/s; P < 0.001; systolic strain rate: 12.2 +/- 3.4 (D) vs. 17.4 +/- 3.2 (C) 1/s; P = 0.012] and during inotropic stimulation [delta velocity (cm/s): 0.2 +/- 0.1 (D) vs. 0.5 +/- 0.3 (C)/5 microg dobutamine; P = 0.002; delta strain rate (1/s): 1.4 +/- 0.9 (D) vs. 3.3 +/- 2.2 (C)/5 microg dobutamine; P = 0.049]. Furthermore, the intraventricular delay in time-to-peak systolic strain was larger in diabetes [20 +/- 18 (D) vs. 10 +/- 7 (C) ms; P= 0.01]. Systolic mitral annular velocity was also lower in the diabeticrats at rest [2.7 +/- 0.4 (D) vs. 3.5 +/- 0.4 (C) cm/s; P < 0.001] and in response to dobutamine [delta velocity (cm/s): 0.1 +/- 0.1 (D) vs. 0.3 +/- 0.2 (C)/5 microg dobutamine; P = 0.013]. CONCLUSION: In experimental diabetes, a reduction in radial and longitudinal LV function and CR can be detected with DMI before the onset of a reduced global LV function.
Authors: Walter A Baseler; Erinne R Dabkowski; Courtney L Williamson; Tara L Croston; Dharendra Thapa; Matthew J Powell; Trust T Razunguzwa; John M Hollander Journal: Am J Physiol Regul Integr Comp Physiol Date: 2010-11-03 Impact factor: 3.619
Authors: Antonio Di Petta; Rafael Simas; Clebson L Ferreira; Vera L Capelozzi; Vera M C Salemi; Luiz F P Moreira; Paulina Sannomiya Journal: Int J Exp Pathol Date: 2015-10-29 Impact factor: 1.925
Authors: Timothy J Roberts; Andrew T Burns; Richard J MacIsaac; Andrew I MacIsaac; David L Prior; André La Gerche Journal: Cardiovasc Diabetol Date: 2018-03-23 Impact factor: 9.951