TY - JOUR
T1 - Strain Rate Acceleration Yields a Better Index for Evaluating Left Ventricular Contractile Function as Compared with Tissue Velocity Acceleration during Isovolumic Contraction Time
T2 - An in Vivo Study
AU - Li, Xiaokui
AU - Jones, Michael
AU - Wang, Hui Fang
AU - Davies, Crispin H.
AU - Swanson, Julia C.
AU - Hashimoto, Ikuo
AU - Rusk, Rosemary A.
AU - Schindera, Sebastian T.
AU - Barber, Brent J.
AU - Sahn, David J.
PY - 2003/12
Y1 - 2003/12
N2 - Objective: Our study aimed to investigate whether strain rate acceleration (SRA) during isovolumic contraction time (IVCT) could serve as a sensitive indicator of myocardial function. Methods: A total of 8 sheep underwent occlusion of left anterior descending coronary artery or diagonal branches and 2 sheep underwent left circumflex coronary artery occlusion to create septal, apical, or basal segment myocardial ischemia 19 to 27 weeks before the study. Baseline, volume-loading, dobutamine, and metoprolol infusion were used to produce 4 hemodynamic stages for each sheep. Doppler tissue imaging was acquired using a 5-MHz probe (GE/VingMed Vivid Five, GE Medical Systems, Milwaukee, Wis) on openchest animals using the liver as a standoff at the apex. Using software (EchoPac, GE Medical Systems), SRA during IVCT was calculated and compared with tissue velocity acceleration (TVA) during IVCT from areas located in the normal and ischemic zones. Also, invasively monitored left ventricle dP/dt was measured as reference contractile function. Results: Both TVA and SRA during IVCT showed higher values for normal tissue than for ischemic area (P < .0001). SRA for normal wall segments changed significantly during the 4 stages (P = .01) with corresponding changes on high-fidelity left ventricular pressure catheters (r = 0.92). TVA over normal segments showed no significant change (P = .29) in the 4 hemodynamic stages. Both TVA and SRA of the ischemic segments showed no significant change with pharmacologic maneuvers or loading conditions. Conclusions: SRA and TVA during IVCT are both useful indicators for detecting abnormal heart wall motion. However, SRA tends to be more sensitive than TVA for differentiating the response to stress conditions.
AB - Objective: Our study aimed to investigate whether strain rate acceleration (SRA) during isovolumic contraction time (IVCT) could serve as a sensitive indicator of myocardial function. Methods: A total of 8 sheep underwent occlusion of left anterior descending coronary artery or diagonal branches and 2 sheep underwent left circumflex coronary artery occlusion to create septal, apical, or basal segment myocardial ischemia 19 to 27 weeks before the study. Baseline, volume-loading, dobutamine, and metoprolol infusion were used to produce 4 hemodynamic stages for each sheep. Doppler tissue imaging was acquired using a 5-MHz probe (GE/VingMed Vivid Five, GE Medical Systems, Milwaukee, Wis) on openchest animals using the liver as a standoff at the apex. Using software (EchoPac, GE Medical Systems), SRA during IVCT was calculated and compared with tissue velocity acceleration (TVA) during IVCT from areas located in the normal and ischemic zones. Also, invasively monitored left ventricle dP/dt was measured as reference contractile function. Results: Both TVA and SRA during IVCT showed higher values for normal tissue than for ischemic area (P < .0001). SRA for normal wall segments changed significantly during the 4 stages (P = .01) with corresponding changes on high-fidelity left ventricular pressure catheters (r = 0.92). TVA over normal segments showed no significant change (P = .29) in the 4 hemodynamic stages. Both TVA and SRA of the ischemic segments showed no significant change with pharmacologic maneuvers or loading conditions. Conclusions: SRA and TVA during IVCT are both useful indicators for detecting abnormal heart wall motion. However, SRA tends to be more sensitive than TVA for differentiating the response to stress conditions.
UR - http://www.scopus.com/inward/record.url?scp=10744222797&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=10744222797&partnerID=8YFLogxK
U2 - 10.1067/j.echo.2003.07.006
DO - 10.1067/j.echo.2003.07.006
M3 - Article
C2 - 14652598
AN - SCOPUS:10744222797
SN - 0894-7317
VL - 16
SP - 1211
EP - 1216
JO - Journal of the American Society of Echocardiography
JF - Journal of the American Society of Echocardiography
IS - 12
ER -