Noninvasive assessment of coronary microvascular dysfunction using Tc-99m tetrofosmin SPECT in patients with acute myocardial infarction.
BACKGROUND
We investigated whether technetium 99m tetrofosmin (TF) single photon emission computed tomography (SPECT) could predict coronary microvascular dysfunction in patients with acute myocardial infarction.


RESULTS
We obtained the regional severity score index (TF-RSSI) using TF SPECT immediately after percutaneous coronary intervention in 25 patients with acute myocardial infarction. Using a Doppler guidewire, we evaluated the deceleration time of diastolic flow velocity (DDT) after percutaneous coronary intervention, and DDT of 600 milliseconds or less was suggested to be an indicator of coronary microvascular dysfunction. Moreover, the chronic regional wall motion score index (RWMSI) was obtained from echocardiography during the chronic phase. There was a good correlation between TF-RSSI and DDT (r = -0.68, P < .01). The optimal cutoff value of TF-RSSI to predict DDT of 600 milliseconds or less was defined as 1.9 or greater (sensitivity, 1.00; specificity, 0.71). The group with poor scintigraphic coronary microvascular function (TF-RSSI > or =1.9, n = 7) demonstrated a significantly shorter DDT (P = .0003), a lower frequency of early systolic retrograde flow (P = .0038), and greater chronic RWMSI (P = .0015) than the group with good scintigraphic coronary microvascular function (TF-RSSI <1.9, n = 15).


CONCLUSIONS
Analysis of TF SPECT immediately after percutaneous coronary intervention in patients with acute myocardial infarction is a useful noninvasive method for evaluating coronary microvascular dysfunction.
Division of Cardiology, Shimada Municipal Hospital, Shimada City, Shizuoka 427-8502, Japan.
Yoshiteru
Y
Abe
Makoto
M
Kondo
Tomoyuki
T
Kubota
Ryota
R
Matsuoka
Makoto
M
Araki
Kiyoshi
K
Doyama
Hitoshi
H
Tanio
D000328:Adult; D000368:Aged; D017115:Catheter Ablation; D005260:Female; D006801:Humans; D008297:Male; D017566:Microvascular Angina / Q000145:classification* / Q000000981:diagnostic imaging* / Q000209:etiology; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery*; D015425:Myocardial Reperfusion; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D016896:Treatment Outcome
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin