G. Derumeaux et al., Tissue Doppler imaging differentiates transmural from nontransmural acute myocardial infarction after reperfusion therapy, CIRCULATION, 103(4), 2001, pp. 589-596
Citations number
29
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Background-The evaluation of transmural extent of necrosis after acute myoc
ardial infarction remains a major problem in clinical practice. We sought t
o determine whether color M-mode tissue Doppler imaging (TDI) could differe
ntiate transmural from nontransmural myocardial infarction.
Methods and Results-Twenty-one anesthetized open-chest dogs underwent 90 or
120 minutes of left anterior descending coronary artery occlusion followed
by 180 minutes of reperfusion, The transmural extension of infarct was mea
sured by triphenyltetrazolium chloride (TTC) staining. Segment shortening i
n the endocardium and epicardium of the anterior and posterior walls was as
sessed by sonomicrometry. Regional myocardial blood flow was measured by ra
dioactive microspheres. TDT was obtained from an epicardial short-axis view
. We calculated systolic and diastolic velocities within the endocardium an
d epicardium of myocardial walls and the subsequent myocardial velocity gra
dient (MVG). TTC staining could identify 2 groups according to the transmur
al extent of necrosis: 15 dogs had a nontransmural (NT) necrosis (42+/-3% o
f wall thickness), and 6 dogs developed a transmural (T) infarct (81+/-4% o
f wall thickness). In both groups, ischemia resulted in a significant and s
imilar reduction in endocardial and epicardial velocities, with a resulting
low systolic MVG in the anterior wall (0.10+/-0.07 in NT and 0.10+/-0.08 s
(-1) in T). At 60 minutes of reperfusion, systolic MVG failed to change sig
nificantly in the transmural group (-0.20+/-0.09 s(-1)). In contrast, it in
creased significantly after reflow in the NT group compared with ischemic v
alues (-0.99+/-0.20 versus 0.10+/-0.07 s(-1), P<0.05).
Conclusions-TDI can differentiate transmural from nontransmural myocardial
infarction early after reperfusion.