Prognostic values of 123I-MIBG myocardial scintigraphy and heart rate variability in patients with heart failure with preserved ejection fraction

Background The aim of this study was to evaluate the prognostic values of sympathetic nerve system using(123)I-MIBG myocardial scintigraphy and using Holter electrocardiogram (ECG) in patients with heart failure with preserved ejection fraction (HFpEF). Methods and results Among 403 consecutive patients with stable HF who underwent(123)I-MIBG myocardial scintigraphy and Holter ECG, we identified 133 patients (64 +/- 16 years) who had preserved ejection fraction (>= 50%) by echocardiography. Multivariate Cox model was used to assess if washout rate (WR) by(123)I-MIBG scintigraphy and very low frequency power (VLFP) by Holter ECG was associated with major adverse cardiovascular events (MACE). During a mean follow-up of 5.4 +/- 4.1 years, 39 MACE occurred. The lower nighttime VLFP (HR 3.29, 95% CI 1.56 to 6.92) and higher WR (HR 4.01, 95% CI 1.63 to 9.88) were the significant prognostic factors for MACE. As compared to high nighttime VLFP and low WR group, MACE risk was significantly the highest in the low nighttime VLFP and high WR group (HR 40.832; 95% CI 5.378 to 310.012,P < 0.001). Conclusion This study demonstrated that the nighttime VLFP adding to WR could be a potential prognostic value among patients with HFpEF.