Gated myocardial SPECT to predict response to beta-blocker therapy in patients with idiopathic dilated cardiomyopathy.
Because of the difficulty of predicting the response of patients with idiopathic dilated cardiomyopathy (IDC) to beta-blocker therapy, this study was performed to evaluate whether gated myocardial SPECT (gated SPECT) could be useful for predicting that response.


METHODS
We performed gated SPECT with (99m)Tc-sestamibi on 38 patients with IDC before treatment with a beta-blocker and standard medication. Perfusion abnormalities, left ventricular (LV) function, and spheric distortion were assessed by a quantitative software program.


RESULTS
We classified patients into 2 groups according to improvement in LV function after 4 mo of therapy. The groups consisted of 16 poor responders whose LV ejection fraction (LVEF) increased less than 10% and 22 good responders whose LVEF increased by 10% or more. The patient characteristics before therapy, including LV volume and LVEF, did not significantly differ between the 2 groups, but the size of the myocardial perfusion defect and spheric distortion were significantly greater in poor responders than in good responders.


CONCLUSIONS
Gated SPECT, by allowing simultaneous assessment of perfusion, function and geometry, might be useful for predicting the response of patients with IDC to beta-blocker therapy.
Fukuchi
Kazuki
K
Department of Radiology, National Cardiovascular Center, Suita, Osaka, Japan. kfukuchi@hsp.ncvc.go.jp
Yasumura
Yoshio
Y
Kiso
Keisuke
K
Hayashida
Kohei
K
Miyatake
Kunio
K
Ishida
Yoshio
Y
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage; D000328:Adult; D000367:Age Factors; D000368:Aged; D017298:Bisoprolol / Q000008:administration & dosage*; D002227:Carbazoles / Q000008:administration & dosage*; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D000077261:Carvedilol; D004359:Drug Therapy, Combination; D005240:Feasibility Studies; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011412:Propanolamines / Q000008:administration & dosage*; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012680:Sensitivity and Specificity; D012737:Sex Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000209:etiology
D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol; D017298:Bisoprolol