Abstract 742: Usefulness of Cardiac I-123 Metaiodobenzylguanidine Imaging for Prediction of Development of Atrial Fibrillation in Patients With Chronic Heart Failure
Background: The prediction of atrial fibrillation (AF) is clinically important for the management of patients with chronic heart failure (CHF). Cardiac I-123 metaiodobenzylguanidine (MIBG) imaging provides prognostic information in patients with CHF. However, it remains unclear whether MIBG imaging could be useful for the prediction of the development of AF.
Methods: We prospectively studied 75 CHF outpatients (NYHA class: 2.0±0.6) with radionuclide left ventricular ejection fraction less than 40% (29±8%). The cardiac MIBG imaging was performed at the entry. The cardiac MIBG heart to mediastinum ratio and washout rate (WR) were calculated from the chest anterior view images obtained at 20 and 200 min after isotope injection. Study patients were divided into two groups with and without abnormal WR >27%.
Results: During the follow-up period of 7.6±3.5 years, 12 (33%) of 36 patients with abnormal WR had the AF development, while the AF development was observed in only 3 (8%) of 39 patients with normal WR. Kaplan-Meier analysis revealed that the AF development was significantly more frequently observed in the abnormal WR group than normal WR group (p=0.002). MIBG WR was significantly greater in patients with than without AF development (38.9±14.9% vs 26.7±12.7%, p=0.002). At multivariate Cox analysis, out of the variables including clinical, echocardiographic, hemodynamic, and MIBG parameters, WR was the only variable significantly associated with the AF development (p=0.04). The hazard ratio of abnormal WR for the AF development was 5.9 (95% CI 1.7–21.0).
Conclusion: Cardiac MIBG WR would be useful to predict the development of atrial fibrillation in CHF patients.