Cardiac I123-MIBG Correlates Better than Ejection Fraction with Symptoms Severity in Systolic Heart Failure

Abstract

BackgroundThe association of autonomic activation, left ventricular ejection fraction (LVEF) and heart failure functional class is poorly understood. ObjectiveOur aim was to correlate symptom severity with cardiac sympathetic activity, through iodine-123-metaiodobenzylguanidine (123I-MIBG) scintigraphy and with LVEF in systolic heart failure (HF) patients without previous beta-blocker treatment. MethodsThirty-one patients with systolic HF, class I to IV of the New York Heart Association (NYHA), without previous beta-blocker treatment, were enrolled and submitted to 123I-MIBG scintigraphy and to radionuclide ventriculography for LVEF determination. The early and delayed heart/mediastinum (H/M) ratio and the washout rate (WR) were performed. ResultsAccording with symptom severity, patients were divided into group A, 13 patients in NYHA class I/II, and group B, 18 patients in NYHA class III/IV. Compared with group B patients, group A had a significantly higher LVEF (25% ± 12% in group B vs. 32% ± 7% in group A, p = 0.04). Group B early and delayed H/M ratios were lower than group A ratios (early H/M 1.49 ± 0.15 vs. 1.64 ± 0.14, p = 0.02; delayed H/M 1.39 ± 0.13 vs. 1.58 ± 0.16, p = 0.001, respectively). WR was significantly higher in group B (36% ± 17% vs. 30% ± 12%, p= 0.04). The variable that showed the best correlation with NYHA class was the delayed H/M ratio (r= -0.585; p=0.001), adjusted for age and sex. ConclusionThis study showed that cardiac 123I-MIBG correlates better than ejection fraction with symptom severity in systolic heart failure patients without previous beta-blocker treatment.

Preoperative iodine-123 meta-iodobenzylguanidine imaging is a novel predictor of left ventricular reverse remodeling during treatment with a left ventricular assist device

“…123 I-MIBG is a recently developed method for assessing inappropriate cardiac sympathetic activity [28]. Numerous studies, including meta-analyses, have demonstrated that both a low early or delayed H/M ratio and an increased WR are associated with advanced stages of HF and a high incidence of fatal arrhythmia, mortality, and morbidity [8][9][10][11][12][13][14][15][16][17][18]. I-MIBG has furthermore proven to be a predictor of both good responses to b-blocker treatment and successful cardiac resynchronization therapy [19,20].…”

“…However, definitive preoperative predictors of this remodeling have not yet been identified. 123 I-metaiodobenzylguanidine ( 123 I-MIBG) is an analog of guanethidine [6] used either to stratify the severity of heart failure (HF) or to predict HF patient prognosis by assessing visualized cardiac sympathetic innervation [7][8][9][10][11][12][13][14][15][16][17][18]. Moreover, 123 I-MIBG has recently been adopted as a tool for predicting or confirming the clinical response to bblocker treatment as well as cardiac resynchronization therapy [19,20].…”

¹²³I-MIBG in Latin America

“…It was detected that H/M ratio and WR correlates better with gravity of symptoms and NYHA functional class than ejection fraction in patients with HF without previous treatment with betablocker (16).…”

Late gadolinium enhancement on cardiac magnetic resonance combined with 123I- metaiodobenzylguanidine scintigraphy strongly predicts long-term clinical outcome in patients with dilated cardiomyopathy

“…Cardiac imaging with 123 I-metaiodobenzylguanidine ( 123 I-MIBG), an analogue of norepinephrine, is a useful tool for detecting abnormal cardiac sympathetic nervous activity in heart failure (HF) patients [3–6]. Increased sympathetic nervous activity in DCM patients is shown to be associated with a poor prognosis [7–9]…”