Long-term prognostic value of analysis of sympathetic drive by myocardial 123I-metaiodobenzylganidine scintigraphy in chronic heart failure.

BACKGROUND

The over increase of sympathetic drive in chronic heart failure (CHF) is with main responsibility for the deterioration and mortality of the disease. Myocardial (123)I-metaiodobenzylganidine (MIBG) scintigraphy is a non-invasive convenient method to assess sympathetic dysfunction in patients with CHF. The aim of the study was to detect if sympathetic antidrive analysed through myocardial MIBG scintigraphy plays a crucial role in long-term prognosis in CHF.

METHODS

Sixty-four enrolled patients underwent myocardial MIBG scintigraphy, and their plasma concentration of brain natriuretic peptide (BNP), myocardial contractile reserve (MCR), rest left ventricular ejection fraction (rest LVEF) and New York Heart Association (NYHA) function class were assessed. They were separated into groups according to median of above parameters. Endpoint was cardiac death and it was recorded in each group during average 54 months' follow-up.

RESULTS

At the end of follow-up, group with lower ratio of heart/mediastinum (H/M) had more death events (P = 0.001), and its BNP level was higher and MCR level was lower (P = 0.003 and 0.001, respectively); but its rest LVEF and NYHA function class were not significantly different. H/M, MCR and BNP correlated closely with death (P = 0.000, 0.000 and 0.001, respectively). Among the three indicators the death risk ratio (RR) of H/M was 4.66, more than MCR and BNP (1.88 and 2.56, respectively). However, rest LVEF and NYHA function class did not correlate with death (P = 0.652 and 0.384, respectively). The group with lower H/M and MCR, higher BNP had much more death than that with higher H/M and MCR, lower BNP, the RR being 12.8.

CONCLUSIONS

Myocardial MIBG scintigraphy is a long-term prognostic marker in CHF. BNP, MCR are also excellent predictors of long-term prognosis in CHF, but not stronger than myocardial MIBG scintigraphy. If the three indicators were joined together, the prediction would become most powerful. Rest LVEF and NYHA have no significance in long-term prediction of CHF.