Prognostic significance of cardiac 123I metaiodobenzylguanidine imaging for mortality and morbidity in patients failure:: a prospective with chronic heart study

Objective-To determine whether cardiac iodine-123 metaiodobenzylguanidine (I-123 MIBG) imaging is useful in predicting the prognosis of patients with chronic heart failure. Design-Cardiac I-123 MIBG imaging was done on entry to the study. The cardiac MIBG washout rate was calculated from anterior chest view images obtained 20 and 200 minutes after injection of the isotope. Study patients were divided into two groups with washout rates above and below 27% (the mean value + 2 SD obtained in 20 normal subjects), and were then followed up. Setting-Tertiary referral centre. Patients-79 patients with chronic heart failure in whom the left ventricular ejection fraction was less than 40%. Results-There were 37 patients in group 1 (washout rate of greater than or equal to 27%) and 42 in group 2 (< 27%). During a follow up period of between 1 and 52 months, eight patients died suddenly and five died of worsening heart failure in group 1, while none died in group 2; 13 patients in group 1 and four in group 2 were admitted to hospital for progressive heart failure. Kaplan-Meier analysis showed that group 1 had a significantly higher mortality and morbidity (p = 0.001 and p < 0.001, respectively) than group 2. Conclusions-Cardiac I-123 MIBG washout rate seems to be a good predictor of prognosis in patients with chronic heart failure.