Author |
이명철(Myung Chul Lee),이경한(Kyung Han Lee),최윤호(Yoon Ho Choi),정준기(June Key Chung),박영배(Young Bae Park),고창순(Chang Soon Koh),문대혁(Dae Hyuk Moon), |
Abstract |
Infarct size is a major determinant of prognosis after
acute myocardial infarction. Up to date, however,
clinically available tests to estimate this size have
not been sufficient]y accurate. Twelve lead
electrocardiogram and wall motion abnormality
measurement are not quantitative, and creatine
phophokinase (CPK) measurement is inaccurate in the
presence of reperfusion or right ventricular
infarction. Methods have been developed to localize and
size acute myocardial infarcts with agents that are
selectively sequestered in areas of myocardial damage,
but previously used agents have lacked sufficient
specificit:y. Antibodies that bind specifically only to
damaged myocardial cells may resolve this problem and
provide an accurate method for noninvasively measuring
infarct size. We determined t.he accuracy with which
infarcted myocardial mass can be measured using single
photon emission computed tomography (SPECT) and
radiolabeled antimyosin antibodies. Seven patients with
acute myocardial infarction and one stable angina
patient were injected with 2 mCi of Indium-111 labeled
antimyosin antibodies. Planar image and SPECT was
performed 24 hours later. None of the patients had
history of prior infarcts, and none had undergone
reperfusion techniques prior to t.he study, which was
done within 4 days of the attack. Planar image showed
all infarct patients to have postive uptakes in the
cardiac region. The location of this uptake correlated
to the infarct site as indicated by electrocardiography
in most of the cases. The angina patient, however,
showed no such abnormai uptake. Infarct size was
determined from transverse slices of the SPECT image
using a 45% threshold value obtained from a phantom
study.Measured infarct size ranged from 40 to 192 gr.
There was significant correlation between the infarct
size measured by SPECT and that estimated from serial
measurements of CPK (r=0.73, p<0,05). These date
suggest that acute myocardiaI infarct size can be
accurately measured from SPECT Indium-111 antimyosin
imaging. This method may be especially valuable in
situations where other methods are unreliable, such as
early reperfusion technique, right ventricular infarct
or presence of prior infarcts. |