CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 5, June 2013
154
AFRICA
Cardiovascular Topics
Comparison of left atrial function in healthy individuals
versus patients with non-ST-segment elevation
myocardial infarction using two-dimensional speckle
tracking echocardiography
ZHU JING, CHEN JIANCHANG, XU WEITING, GAO LAN, FARHAN SHAIKH, WU YANNI
Abstract
Left atrial (LA) function has been associated with adverse
outcomes in patients after acute myocardial infarction. The
purpose of the current study was to evaluate LA function in
patients with non-ST-segment elevation myocardial infarc-
tion (NSTEMI) by two-dimensional speckle tracking echo-
cardiography (2D STE). Fifty-one patients with NSTEMI and
40 age-matched normal control individuals were enrolled in
this study. Conventional echocardiographic parameters and
global longitudinal strain rate (GLSR) were measured at left
ventricular (LV) and LA segments. Compared with healthy
subjects, patients with NSTEMI had significantly increased
LA volumes but significantly decreased LA emptying frac-
tion and GLSR. LA-GLSR had significant correlations
with the 2D Doppler echocardiographic parameters of LA
function. In particular, global LA peak negative strain rate
during early ventricular diastole (LA-GLSRe) was signifi-
cantly correlated with both LA 2D Doppler echocardio-
graphic parameters and LV contractile function. This could
be suggested as a better indicator to evaluate LA function as
a preferred parameter of STE.
Keywords:
two-dimensional speckle tracking echocardiogra-
phy, strain rate, non-ST-segment elevation myocardial infarc-
tion, left atrial function
Submitted 25/11/11, accepted 13/3/13
Cardiovasc J Afr
2013;
24
: 154–160
DOI: 10.5830/CVJA-2013-011
According to an authoritative survey, more than one million
people die each year from coronary artery disease in China.
Recently, impaired left atrial (LA) function and its detrimental
effect on coronary artery disease has caused wide concern,
1
Left
atrial function is one of the most important clinical parameters of
two-dimensional speckle tracking echocardiography (2D STE),
which is an innovative tool for more comprehensive and reliable
echocardiographic evaluation of myocardial function.
2
Compared with Doppler and 2D echocardiography, 2D STE
has the advantages of angle independence, and is also less
affected by reverberations, side lobes or drop-out artifacts. While
this novel echocardiographic method has been frequently used to
assess LV function,
3
it has more recently been used to evaluate
atrial function in normal subjects and in conditions with atrial
dysfunction.
4,5
The aims of this study were to examine left atrial function
using 2D STE in patients with non-ST-segment elevation
myocardial infarction (NSTEMI) compared to healthy subjects
and to define the feasibility of speckle tracking-based strain rate
(SR) imaging for the evaluation of LA dysfunction after acute
myocardial ischaemia.
Methods
Fifty-one patients (43 males and eight females; mean age
62.9
±
11.1 years) were treated by percutaneous coronary
intervention (PCI) for NSTEMI and were included in the study
from December 2009 to November 2010, while 40 age-matched
healthy subjects (35 males and five females; mean age 60.1
±
9.8
years) with normal treadmill exercise stress echocardiography
and no coronary risk factors were enrolled as a control group.
Patients with atrial fibrillation or flutter, valvular heart
disease (of mild or greater severity), and poor left atrial images
were excluded. The study protocol was approved by the Ethics
Committee of the Second Affiliated Hospital of Soochow
University and a written informed consent was obtained from
each participant.
Conventional 2D and Doppler echocardiography studies were
performed using the Vivid7 Dimension ultrasound system (GE,
USA) equipped with a 3S phased-array transducer (frequency
range of 1.7–3.4 MHz). Echocardiographies of patients were
performed 2.8
±
0.6 days after NSTEMI. Cardiac dimensions
were measured in accordance with recommendations of the
American Society of Echocardiography.
M-mode echocardiography was used to measure LV
end-diastolic and end-systolic diameters. LV ejection fraction
(LVEF) was calculated from apical four- and two-chamber
Department of Cardiology, Second Affiliated Hospital of
Soochow University, Suzhou, China
ZHU JING, MD
CHEN JIANCHANG, MD, PhD,
XU WEITING, MD
GAO LAN, MD
FARHAN SHAIKH, MD
WU YANNI, MD
