Resumen de Impact of Diabetes on Cardiac Sympathetic Innervation in Patients With Heart Failure:: A ^sup 123^I meta-iodobenzylguanidine (^sup 123^I MIBG) scintigraphic study
Stefania Paolillo, Giuseppe Rengo, Gennaro Pagano, Teresa Pellegrino, Gianluigi Savarese, Grazia D. Femminella, Marianna Tuccillo, Antonio Boemio, Emilio Attena, Roberto Formisano, Laura Petraglia, Francesco Scopacasa, Gennaro Galasso, Dario Leosco, Bruno Trimarco, Alberto Cuocolo, Pasquale Perrone Filardi
Impaired parasympathetic and sympathetic nervous system activity have been demonstrated in patients with diabetes mellitus (DM) and correlated with worse prognosis. Few data are available on the effect of DM on cardiac neuropathy in heart failure (HF). The aim of the current study was to assess cardiac sympathetic activity in HF patients with and without DM. Patients with severe HF (n = 75), with (n = 37) and without DM (n = 38), and 14 diabetic patients with normal cardiac function underwent 123I meta-iodobenzylguanidine scintigraphy from which early and late heart-to-mediastinum (H/M) ratios were calculated. Clinical, echocardiographic, and biochemical data were measured. DM compared with non-DM patients showed significantly lower early (1.65 ± 0.21 vs. 1.75 ± 0.21; P < 0.05) and late H/M ratios (1.46 ± 0.22 vs. 1.58 ± 0.24; P < 0.03). Early and late H/M were significantly higher in DM patients without HF (2.22 ± 0.35 and 1.99 ± 0.24, respectively) than HF patients with (P < 0.0001) and without (P < 0.0001) DM. In HF patients, an inverse correlation between early or late H/M ratio and hemoglobin A1c (HbA1c) (Pearson = -0.473, P = 0.001; Pearson = -0.382, P = 0.001, respectively) was observed. In DM, in multivariate analysis, HbA1c and ejection fraction remained significant predictors of early H/M; HbA1c remained the only significant predictor of late H/M. No correlation between early or late H/M and HbA1c was found in non-DM patients. Diabetic patients with HF show lower cardiac sympathetic activity than HF patients not having DM or than DM patients with a similar degree of autonomic dysfunction not having HF. HbA1c correlated with the degree of reduction in cardiac sympathetic activity.
