  |
DETECTION of
MYOCARDIAL NECROSIS /
ACUTE MYOCARDIAL INFARCTION
Detection of acute myocardial necrosis can be done with 99mTechnetium-pyrophosphate
or by 111In-antimyosin antibody imaging which has recently been approved by the
Food and Drug Administration. With both these 2 tracers, positive results are obtained
only 24-48 hours after acute infarction and therefore, the clinical utility of these
techniques have been limited. The main indication being patients with equivocal diagnosis
of acute infarction or those who arrive late to the hospital and in whom the enzymes
changes may have been missed (Figure 9). On the horizon, however, there is a new agent
called 99mTc-glucurate which produces positive results within an hour after
acute myocardial infarction and this technique may prove to be useful in patients with
chest pains but nondiagnostic ECG or enzyme changes.12
FIGURE 9:
|
(Click image to enlarge.)
Indium-111 antimyosin images showing increased uptake in
the lateral wall (panel A) in a patient with recent acute lateral myocardial infarction.
|
|
(Click image to enlarge. Photos used with
permission.)
In panel B, there is uptake in the inferior wall, in a
patient with recent acute inferior wall myocardial infarction.
|
Antimyosin antibody imaging, however, is useful in the
detection of rejection after cardiac transplantation and may be used complimentary to, or
in lieu of, serial biopsies, in detection of myocarditis and in dual isotope imaging
(thallium or Tc-perfusion agent and antimyosin) to detect infarcted myocardium and viable
myocardium in post acute infarct patients.
[ Back ] [ Next ] |
