Impact of endothelial dysfunction on left ventricular remodeling after successful primary coronary angioplasty for acute myocardial infarction--analysis by quantitative ECG-gated SPECT--.
BACKGROUND
We hypothesized that endothelial cell integrity in the risk area would influence left ventricular remodeling after acute myocardial infarction.


METHODS
Twenty patients (61 +/- 8 y.o.) with acute myocardial infarction underwent 99mTc-tetrofosmin imaging in the subacute phase and three months after successful primary angioplasty due to myocardial infarction. All patients were administered angiotensin-converting enzyme inhibitor after revascularization. Cardiac scintigraphies with quantitative gated SPECT were performed at the sub-acute stage and again 3 months after revascularization to evaluate left ventricular (LV) remodeling. The left ventricular ejection fraction (EF) and end-systolic and end-diastolic volume (ESV, EDV) were determined using a quantitative gated SPECT (QGS) program. Three months after myocardial infarction, all patients underwent cardiac catheterization examination with coronary endothelial function testing. Bradykinin (BK) (0.2, 0.6, 2.0 microg/min) was administered via the left coronary artery in a stepwise manner. Coronary blood flow was evaluated by Doppler flow velocity measurement. Patients were divided into two groups by BK-response: a preserved endothelial function group (n = 10) and endothelial dysfunction group (n = 10).


RESULTS
At baseline, both global function and LV systolic and diastolic volumes were similar in both groups. However, LV ejection fraction was significantly improved in the preserved-endothelial function group, compared with that in the endothelial dysfunction group (42 +/- 10% to 48 +/- 9%, versus 41 +/- 4% to 42 +/- 13%, p < 0.05). LV volumes progressively increased in the endothelial dysfunction group compared to the preserved-endothelial, function group (123 +/- 45 ml to 128 +/- 43 ml, versus 111 +/- 47 ml to 109 +/- 49 ml, p < 0.05).


CONCLUSIONS
In re-perfused acute myocardial infarction, endothelial function within the risk area plays an important role with left ventricular remodeling after myocardial infarction.
Department of Cardiovascular and Respiratory Medicine, Shiga University of Medical Science, Japan.
Shinro
S
Matsuo
Ichiro
I
Nakae
Tetsuya
T
Matsumoto
Minoru
M
Horie
D015906:Angioplasty, Balloon, Coronary; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging*; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy*; D011379:Prognosis; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology / Q000517:prevention & control*