Dynamic 123I-MIBG SPECT reflects sympathetic nervous integrity and predicts clinical outcome in patients with chronic heart failure.
123I-metaiodobenzylguanidine (123I-MIBG) is useful for assessment of the severity and prognosis of patients with chronic heart failure (CHF). To examine 123I-MIBG kinetics in the early phase soon after tracer injection, we performed dynamic single photon emission computed tomography (SPECT) in 76 patients with CHF and 17 control subjects. The consecutive 15 images of 2 min-dynamic SPECT were acquired for 30 min after injection. From 0 to 4 min, a significant amount of radioactivity existed in the blood pool, thus we calculated washout rate of 123I-MIBG from 4 to 30 min (%WR-E). Patients were followed up with an end-point of cardiac death or re-hospitalization for 16 months (6-30 months). As the NYHA functional class advanced, %WR-E increased (control, NYHA class I, II, and III: 9 +/- 4%, 10 +/- 5%, 12 +/- 5%, and 17 +/- 5%*, respectively, *p < 0.01 vs. all other groups). Significant correlation was found between %WR-E and conventional WR from 30 min to 240 min (r = 0.606, p < 0.0001). %WR-E was positively correlated with left ventricular end-diastolic dimension (r = 0.372, p < 0.01) and was inversely correlated with left ventricular fractional shortening (r = -0.316, p < 0.02). The normal upper limit of %WR-E was defined as mean + 2SD value of 17 control subjects (17.1%). Patients with abnormally rapid %WR-E levels had a higher cardiac event rate than those with normal %WR-E levels (57% vs. 12%, p < 0.0001). These data suggest that washout rate of 123I-MIBG in the early phase from 4 min to 30 min (%WR-E) reflects cardiac sympathetic nervous integrity and is useful to evaluate the severity and prognosis of patients with CHF. The present results indicate a potential role of dynamic SPECT in shortening the 123I-MIBG imaging protocol.
Arimoto
Takanori
T
First Department of Internal Medicine, Yamagata University School of Medicine, Iida-Nishi, Japan.
Takeishi
Yasuchika
Y
Fukui
Akio
A
Tachibana
Hidetada
H
Nozaki
Naoki
N
Hirono
Osamu
O
Yamaguchi
Hiroyuki
H
Itoh
Makoto
M
Miyamoto
Takuya
T
Takahashi
Hiroki
H
Okada
Akio
A
Takahashi
Kazuei
K
Kubota
Isao
I
D019797:3-Iodobenzylguanidine; D001342:Autonomic Nervous System Diseases / Q000150:complications / Q000000981:diagnostic imaging* / Q000188:drug therapy; D002316:Cardiotonic Agents / Q000627:therapeutic use; D002908:Chronic Disease; D018572:Disease-Free Survival; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000209:etiology / Q000401:mortality*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D019275:Radiopharmaceuticals; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012720:Severity of Illness Index; D013564:Sympathetic Nervous System / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000627:therapeutic use
D002316:Cardiotonic Agents; D019275:Radiopharmaceuticals; D014665:Vasodilator Agents; D019797:3-Iodobenzylguanidine